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Hypophosphatasia: A Unique Disorder of Bone Mineralization. Int J Mol Sci 2021; 22:ijms22094303. [PMID: 33919113 PMCID: PMC8122659 DOI: 10.3390/ijms22094303] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/18/2021] [Accepted: 04/19/2021] [Indexed: 12/25/2022] Open
Abstract
Hypophosphatasia (HPP) is a rare genetic disease characterized by a decrease in the activity of tissue non-specific alkaline phosphatase (TNSALP). TNSALP is encoded by the ALPL gene, which is abundantly expressed in the skeleton, liver, kidney, and developing teeth. HPP exhibits high clinical variability largely due to the high allelic heterogeneity of the ALPL gene. HPP is characterized by multisystemic complications, although the most common clinical manifestations are those that occur in the skeleton, muscles, and teeth. These complications are mainly due to the accumulation of inorganic pyrophosphate (PPi) and pyridoxal-5′-phosphate (PLP). It has been observed that the prevalence of mild forms of the disease is more than 40 times the prevalence of severe forms. Patients with HPP present at least one mutation in the ALPL gene. However, it is known that there are other causes that lead to decreased alkaline phosphatase (ALP) levels without mutations in the ALPL gene. Although the phenotype can be correlated with the genotype in HPP, the prediction of the phenotype from the genotype cannot be made with complete certainty. The availability of a specific enzyme replacement therapy for HPP undoubtedly represents an advance in therapeutic strategy, especially in severe forms of the disease in pediatric patients.
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Karakostas P, Dolscheid-Pommerich R, Hass MD, Weber N, Brossart P, Schäfer VS. [Prevalence of hypophosphatasia in adult patients in rheumatology]. Z Rheumatol 2021; 81:513-519. [PMID: 33852075 PMCID: PMC9338116 DOI: 10.1007/s00393-021-00994-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/10/2021] [Indexed: 11/29/2022]
Abstract
Hintergrund Die Hypophosphatasie (HPP) ist eine genetische Erkrankung, die durch eine oder mehrere Mutationen im Gen für alkalische Phosphatase (ALP) verursacht wird, verantwortlich für die Kodierung der gewebespezifischen ALP und für den Mineralisierungsprozess. Ziel der Arbeit Bestimmung der Prävalenz der HPP bei rheumatologischen Patienten. Material und Methoden Retrospektive Analyse der Krankenakten aller erwachsener Patienten mit pathologisch erniedrigten gesamt ALP-Werten (<35 U/l), die zwischen Januar 2017 und Juni 2019 in der Rheumatologie der Medizinischen Klinik III am Universitätsklinikum Bonn behandelt wurden. Die Analyse wurde in Bezug auf klinische Zeichen sowie auf die Ergebnisse der Gentests für HPP untersucht. Ergebnisse Bei 60 von 2289 Patienten (2,62 %) zeigten sich pathologisch niedrige ALP-Werte, bei 30 von ihnen (1,31 %) wurden persistierend niedrige ALP-Werte festgestellt. Bei 19 dieser 30 Patienten wurde ein Gentest für ALP-Genmutationen durchgeführt. Sieben der 19 Patienten (36,84 %) hatten HPP-Zeichen (Insuffizienzfrakturen oder schlechter Zahnstatus seit der Kindheit), alle mit pathologischer ALP-Mutation. Drei dieser Patienten (15,78 %) hatten jeweils eine Insuffizienzfraktur mit normwertiger Knochendichtemessung in der Vorgeschichte. Insgesamt 13 von 19 Patienten wiesen (68,42 %) Mutationen im ALP-Gen auf. Interessanterweise wurde keine Assoziation mit einer Chondrokalzinose festgestellt. Diskussion Die HPP scheint eine unterdiagnostizierte Erkrankung mit einem höheren Anteil betroffener Patienten, welche in der Rheumatologie vorstellig werden, zu sein. Daher sollten zukünftige Studien darauf abzielen, ein Diagnostikprotokoll in der klinischen Praxis zu entwickeln.
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Affiliation(s)
- P Karakostas
- Klinik für Innere Medizin III, Onkologie, Hämatologie, Rheumatologie und Klinische Immunologie, Universitätsklinikum Bonn, Venusberg Campus 1, 53127, Bonn, Deutschland.
| | - R Dolscheid-Pommerich
- Institut für Klinische Chemie und Klinische Pharmakologie, Universitätsklinikum Bonn, Bonn, Deutschland
| | - M D Hass
- Zentrum für Blutgerinnungsstörungen und Transfusionsmedizin Bonn, Bonn, Deutschland
| | - N Weber
- Klinik für Innere Medizin III, Onkologie, Hämatologie, Rheumatologie und Klinische Immunologie, Universitätsklinikum Bonn, Venusberg Campus 1, 53127, Bonn, Deutschland
| | - P Brossart
- Klinik für Innere Medizin III, Onkologie, Hämatologie, Rheumatologie und Klinische Immunologie, Universitätsklinikum Bonn, Venusberg Campus 1, 53127, Bonn, Deutschland
| | - V S Schäfer
- Klinik für Innere Medizin III, Onkologie, Hämatologie, Rheumatologie und Klinische Immunologie, Universitätsklinikum Bonn, Venusberg Campus 1, 53127, Bonn, Deutschland
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Vieira LHR, Peixoto KC, Flósi CL, de Farias MLF, Madeira M. Active search of adult patients with persistently low serum alkaline phosphatase levels for the diagnosis of hypophosphatasia. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2021; 65:289-294. [PMID: 33844893 PMCID: PMC10065342 DOI: 10.20945/2359-3997000000347] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Objective Alkaline phosphatase (ALP) is the main laboratory marker of hypophosphatasia (HPP), a rare disease unknown to most physicians. The prevalence of HPP has been widely discussed in the literature due to the diverse phenotypes of HPP. The purpose of this study was to search for patients with hypophosphatasemia based on previous biochemistry tests and reevaluate them to confirm the diagnosis of HPP. Methods A total of 289,247 biochemical tests for ALP in adults were performed from 2015 to 2019 in two tertiary hospitals in Rio de Janeiro were reviewed (Clementino Fraga Filho University Hospital - HUCFF - and Bonsucesso Federal Hospital - BFH). Results A total of 1,049 patients were identified with ALP levels below 40 U/L, and 410 patients had hypophosphatasemia confirmed by at least two exams. After the active search of medical reports and/or interviews based on structured questionnaires, 398 subjects were excluded due to secondary causes of reduced ALP. The remaining 12 patients were invited to attend the medical consultation at HUCFF, accompanied by at least one first-degree relative. None of the patients or their relatives had a history or clinical manifestations consistent with HPP. Serum ALP was within reference values in all relatives, but persistently low in further laboratory evaluation in all the 12 patients, in whom secondary causes were ruled out. Thus, we cannot exclude the possibility that they might carry the mutations associated with HPP. Conclusion Further image evaluations and genetic testing would be appropriate to confirm this asymptomatic adult form of HPP.
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Affiliation(s)
- Lucio Henrique Rocha Vieira
- Divisão de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil,
| | - Kleison Cordeiro Peixoto
- Laboratório de Bioquímica, Hospital Universitário Clementino Fraga Filho, Rio de Janeiro, RJ, Brasil
| | - Caroline Leal Flósi
- Divisão de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Maria Lucia Fleiuss de Farias
- Divisão de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
| | - Miguel Madeira
- Divisão de Endocrinologia, Hospital Universitário Clementino Fraga Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brasil
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Liu M, Liu M, Liang X, Wu D, Li W, Su C, Cao B, Chen J, Gong C. Clinical and genetic characteristics of hypophosphatasia in Chinese children. Orphanet J Rare Dis 2021; 16:159. [PMID: 33827627 PMCID: PMC8028151 DOI: 10.1186/s13023-021-01798-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 03/30/2021] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Hypophosphatasia (HPP) is a rare inherited disorder, which is caused by loss-of-function mutations in the ALPL gene. HPP is a heterogeneous disease that has a wide spectrum of phenotypes. Few studies were carried out in the Chinese population with HPP, especially in children. METHODS The clinical and genetic characteristics of 10 Chinese children with HPP who were referred to the Beijing Children's Hospital were described. Previously reported HPP cases of children in China were also reviewed. RESULTS A total of 33 cases were identified, which included 2 perinatal lethal HPP, 10 infantile HPP, 10 childhood HPP, and 11 odonto HPP. The male-to-female ratio was 24:9. The average age at onset was 0.69 years (ranged from 2 h after birth to 14 years), while the average age at clinical diagnosis was 3.87 years (ranged from 2 h after birth to 19 years). Serum alkaline phosphatase (ALP) levels were significantly decreased in patients with perinatal lethal/infantile HPP when compared with those with the mild forms of HPP childhood/odonto HPP (P < 0.01). Although serum phosphate levels were not different (P > 0.05), serum calcium levels were elevated, and serum intact parathyroid hormone levels were decreased in patients with perinatal lethal/infantile HPP in comparison with those with the childhood/odonto HPP (P all < 0.01). Genetic analyses identified 40 mutations in 31 HPP cases, including 28 missense mutations, 9 frameshift mutations, 2 splice junction alterations, and 1 regulatory mutation. Of which, 5 novel mutations were identified in our present study: 2 frameshift mutations (p.Arg138GlyfsTer27, p.Leu511Profs*272); 2 missense mutations (p.Ala176Val, p.Phe268Leu), and 1 splice junction alteration (c.297+5G>A). Compound heterozygous mutations accounted for 80.6% of all variants. No mutational "hot-spot" was found. Most mutations of ALPL were located in exons 5, 7, 10, and 3. Notably, subjects that carrying single heterozygous mutations showed milder phenotypes of HPP, while subjects with nonsense mutations were associated with a severer phenotype. CONCLUSIONS HPP is a rare disease with often delayed diagnosis, and the incidence of HPP in China may be seriously underestimated. The present study expands the phenotypic and genotypic spectrum and the understanding of HPP in Chinese children. These findings will be useful for clinical assessment and shorten the diagnosis time for pediatric HPP in China.
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Affiliation(s)
- Meijuan Liu
- Department of Endocrinology, Genetics and Metabolism, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Min Liu
- Department of Endocrinology, Genetics and Metabolism, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Xuejun Liang
- Department of Endocrinology, Genetics and Metabolism, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Di Wu
- Department of Endocrinology, Genetics and Metabolism, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Wenjing Li
- Department of Endocrinology, Genetics and Metabolism, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Chang Su
- Department of Endocrinology, Genetics and Metabolism, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Bingyan Cao
- Department of Endocrinology, Genetics and Metabolism, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Jiajia Chen
- Department of Endocrinology, Genetics and Metabolism, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China
| | - Chunxiu Gong
- Department of Endocrinology, Genetics and Metabolism, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, 100045, China.
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Koehler K, Atway S, Pipes J, Ing S. Diagnosis of Hypophosphatasia in Adults Presenting With Metatarsal Stress Fracture: Proof-of-Concept for a Case-Finding Strategy. JBMR Plus 2021; 5:e10495. [PMID: 34189384 PMCID: PMC8216134 DOI: 10.1002/jbm4.10495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 02/16/2021] [Accepted: 03/17/2021] [Indexed: 11/18/2022] Open
Abstract
Hypophosphatasia (HPP) is caused by loss‐of‐function mutations in ALPL resulting in decreased alkaline phosphatase (ALP) activity. Metatarsal stress fracture (MSF) is a common clinical feature of hypophosphatasia in adults. In this study, the primary objectives were to determine whether new cases of ALPL variants could be identified in patients with MSF and who also had serum ALP concentration below the reference range and to phenotype their clinical course. Electronic health records were queried for adult patients with MSF using International Classification of Disease codes (ICD‐9, ICD‐10CM) and ALP measurements. Patients with ALP levels below the normal limit were invited to receive mutational analysis of ALPL and to complete the following surveys: the Short Form 36 version 2 (SF36v2), the Brief Pain Inventory‐Short Form (BPI), and the Health Assessment Questionnaire Disability Index (HAQ‐DI). Cases with and controls without ALPL pathogenic variants were compared by survey scores and clinical variables relevant to fracture. In 1611 patients with MSF presenting to a podiatry clinic (10/1/2011–10/1/2017), 937 had ALP measurement, of whom 13 (1.4%) had ALP levels below the lower normal limit. In eight patients consenting to participate, two had heterozygous pathogenic ALPL variants. ALPL variants were found in 2 of 1611 patients (0.12%) with MSF, 2 patients of 937 (0.21%) in those with MSF and any ALP measurement, and 2 of 13 patients (15%) in MSF and decreased ALP level. Cases versus controls rated lower scores on eight of eight SF36v2 scales (range, 0–100); higher scores for worst pain (8.0 vs. 0.8) and average pain (6.0 vs. 0.7) on the BPI (range, 0–10); and higher standard disability score (1.4 vs. 0) on the HAQ‐DI (range, 0–3). These data provide proof‐of‐concept for HPP case identification in patients presenting to a podiatry clinic with MSF, suggesting a search for historically low ALP levels may be a useful step for consideration of HPP diagnosis, and supports a prospective study to determine an optimal case‐finding strategy. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Kenna Koehler
- Ohio State University College of Medicine Columbus OH USA
| | - Said Atway
- Division of Podiatry Ohio State University Wexner Medical Center Columbus OH USA
| | - James Pipes
- Division of Podiatry Ohio State University Wexner Medical Center Columbus OH USA
| | - Steven Ing
- Department of Internal Medicine, Division of Endocrinology, Diabetes and Metabolism Ohio State University Wexner Medical Center Columbus OH USA
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Jandl NM, Schmidt T, Rolvien T, Stürznickel J, Chrysostomou K, von Vopelius E, Volk AE, Schinke T, Kubisch C, Amling M, Barvencik F. Genotype-Phenotype Associations in 72 Adults with Suspected ALPL-Associated Hypophosphatasia. Calcif Tissue Int 2021; 108:288-301. [PMID: 33191482 PMCID: PMC7881968 DOI: 10.1007/s00223-020-00771-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 10/12/2020] [Indexed: 12/11/2022]
Abstract
Hypophosphatasia (HPP) is a rare inborn error of metabolism due to a decreased activity of tissue nonspecific alkaline phosphatase (TNSALP). As the onset and severity of HPP are heterogenous, it can be challenging to determine the pathogenicity of detected rare ALPL variants in symptomatic patients. We aimed to characterize patients with rare ALPL variants to propose which patients can be diagnosed with adult HPP. We included 72 patients with (1) clinical symptoms of adult HPP or positive family history and (2) low TNSALP activity and/or high pyridoxal 5'-phosphate (PLP) levels, who underwent ALPL gene sequencing. The patients were analyzed and divided into three groups depending on ALPL variant pathogenicity according to the classification of the American College of Medical Genetics and Genomics (ACMG). Reported pathogenic (n = 34 patients), rare (n = 17) and common (n = 21) ALPL variants only were found. Muscular complaints were the most frequent symptoms (> 80%), followed by bone affection (> 50%). Tooth involvement was significantly more common in patients with pathogenic or rare ALPL variants. Seven rare variants could be classified as likely pathogenic (ACMG class 4) of which five have not yet been described. Inconclusive genetic findings and less specific symptoms make diagnosis difficult in cases where adult HPP is not obvious. As not every pathogenic or rare ALPL variant leads to a manifestation of HPP, only patients with bone complications and at least one additional complication concerning teeth, muscle, central nervous and mental system, repeated low TNSALP activity and high PLP levels should be diagnosed as adult HPP if rare ALPL gene variants of ACMG class 4 or higher support the diagnosis.
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Affiliation(s)
- Nico Maximilian Jandl
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestrasse 59, 22529, Hamburg, Germany
- Department of Orthopedics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Tobias Schmidt
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestrasse 59, 22529, Hamburg, Germany
| | - Tim Rolvien
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestrasse 59, 22529, Hamburg, Germany
- Department of Orthopedics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Julian Stürznickel
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestrasse 59, 22529, Hamburg, Germany
| | - Konstantin Chrysostomou
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestrasse 59, 22529, Hamburg, Germany
| | - Emil von Vopelius
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestrasse 59, 22529, Hamburg, Germany
- Department of Orthopedics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Alexander E Volk
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Thorsten Schinke
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestrasse 59, 22529, Hamburg, Germany
| | - Christian Kubisch
- Institute of Human Genetics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Michael Amling
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestrasse 59, 22529, Hamburg, Germany
| | - Florian Barvencik
- Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf, Lottestrasse 59, 22529, Hamburg, Germany.
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Desborough R, Nicklin P, Gossiel F, Balasubramanian M, Walsh JS, Petryk A, Teynor M, Eastell R. Clinical and biochemical characteristics of adults with hypophosphatasia attending a metabolic bone clinic. Bone 2021; 144:115795. [PMID: 33301960 DOI: 10.1016/j.bone.2020.115795] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 11/12/2020] [Accepted: 12/03/2020] [Indexed: 12/18/2022]
Abstract
OBJECTIVES This study sought to identify the clinical and biochemical characteristics that would help distinguish hypophosphatasia (HPP) from other metabolic bone diseases in adult patients attending a metabolic bone clinic by comparing patients who have genetically confirmed HPP with a group of patients with low bone mineral density (BMD) in the osteoporotic or osteopenic range. METHODS Data were collected from February 2016 to October 2018 for 41 patients (n = 20 in the HPP group, n = 21 in the low-BMD group) attending the metabolic bone clinic at Sheffield, United Kingdom (UK) or who were recruited via the Rare UK Diseases Study (RUDY) platform during the same period. A study questionnaire was administered to all patients, and assessments were conducted for laboratory values, physical functions, BMD, and spine imaging. RESULTS Patients with HPP were characterized as being younger, more likely to have metatarsal or femoral shaft fractures, and less likely to have vertebral fractures compared with patients in the low-BMD group. The HPP group had lower total and bone-specific alkaline phosphatase, higher pyridoxal 5'-phosphate (PLP), and lower, albeit sufficient, 25-hydroxyvitamin D. Low-BMD group had lower C-terminal telopeptide and tartrate-resistant acid phosphatase 5b (61.9% were on bisphosphonates at enrollment). Dual X-ray absorptiometry (DXA) analysis found that the HPP group had higher total hip and lumbar BMD T- and Z-scores compared with the low-BMD group. There were no differences found between the two groups with physical functional assessments. Results of receiver operating characteristic analysis indicated strong diagnostic accuracy of these biomarkers for HPP. Thresholds of total alkaline phosphatase (ALP) activity of 43 IU/L or less and PLP level of 120 nmol/L or more were determined to be potentially clinically useful for distinguishing HPP from other metabolic bone diseases. CONCLUSION This study supported the use of ALP and PLP measurements as predictive of HPP diagnosis along with certain demographic and clinical characteristics (younger age, metatarsal or femoral fractures without low mean BMD T- and Z-scores on a DXA scan) that can aid in recognizing adults who should be further evaluated for HPP. The critical values identified need to be applied to an independent sample to be tested for diagnostic accuracy.
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Affiliation(s)
| | - Philip Nicklin
- Academic Unit of Bone Metabolism, University of Sheffield, Sheffield, UK
| | - Fatma Gossiel
- Academic Unit of Bone Metabolism, University of Sheffield, Sheffield, UK; Mellanby Centre for Musculoskeletal Research, University of Sheffield, Sheffield, UK
| | - Meena Balasubramanian
- Sheffield Clinical Genetics Service, Sheffield Children's National Health Service, Foundation Trust, Western Bank, Sheffield, UK; Mellanby Centre for Musculoskeletal Research, University of Sheffield, Sheffield, UK
| | - Jennifer S Walsh
- Academic Unit of Bone Metabolism, University of Sheffield, Sheffield, UK; Mellanby Centre for Musculoskeletal Research, University of Sheffield, Sheffield, UK
| | - Anna Petryk
- Alexion Pharmaceuticals, Inc., Boston, MA, USA
| | | | - Richard Eastell
- Academic Unit of Bone Metabolism, University of Sheffield, Sheffield, UK; Mellanby Centre for Musculoskeletal Research, University of Sheffield, Sheffield, UK.
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Genest F, Claußen L, Rak D, Seefried L. Bone mineral density and fracture risk in adult patients with hypophosphatasia. Osteoporos Int 2021; 32:377-385. [PMID: 32879991 PMCID: PMC7838076 DOI: 10.1007/s00198-020-05612-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 08/25/2020] [Indexed: 02/01/2023]
Abstract
UNLABELLED In adult hypophosphatasia (HPP) patients, elevated lumbar spine dual X-ray absorptiometry (DXA) values are associated with markers of disease severity and disease-specific fracture risk while femoral bone mineral density (BMD), being largely unaffected by the disease severity, may still be useful to monitor other causes of increased fracture risk due to low BMD. INTRODUCTION Hypophosphatasia (HPP) is a rare inherited metabolic disorder due to deficient activity of the tissue-nonspecific alkaline phosphatase (TNAP). Clinical manifestation in adult HPP patients is manifold including an increased risk for fractures, but data regarding clinical significance of DXA measurement and associations with fracture risk and disease severity is scarce. METHODS Retrospective single-center analysis of DXA scans in patients with confirmed HPP (documented mutation, clinical symptoms, low alkaline phosphatase activity). Further data evaluation included disease-related fractures, laboratory results (alkaline phosphatase, pyridoxalphosphate, phosphoethanolamine), and medical history. RESULTS Analysis included 110 patients (84 female, mean age of 46.2 years) of whom 37.3% (n = 41) were harboring two mutations. Average T-Score level at the lumbar spine was - 0.1 (SD 1.9), and mean total hip T-Score was - 1.07 (SD 0.15). Both lower ALP activity and higher substrate levels (pyridoxalphosphate and phosphoethanolamine) were significantly correlated with increased lumbar spine T-Score levels (p < 0.001) while BMD at the hip was not affected by indicators of disease severity. Increased lumbar spine BMD was significantly associated with an increased risk for HPP-related fractures, prevalent in 22 (20%) patients (p < 0.001) with 21 of them having biallelic mutations. CONCLUSION BMD in adult HPP patients is not systematically reduced. Conversely, increased lumbar spine BMD appears to be associated with severely compromised mineralization and increased risk for HPP-related fractures while BMD at the hip appears unaffected by indicators of disease severity, suggesting suitability of this anatomic location for assessing and discerning disorders with increased fracture risk owing to reduced BMD like osteoporosis. TRIAL REGISTRATION NUMBER German register for clinical studies (DRKS00014022) DATE OF REGISTRATION: 02/10/2018 - retrospectively registered.
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Affiliation(s)
- F Genest
- Clinical Trial Unit, Orthopedic Department, University of Wuerzburg, Brettreichstrasse 11, 97074, Wuerzburg, Germany
| | - L Claußen
- Clinical Trial Unit, Orthopedic Department, University of Wuerzburg, Brettreichstrasse 11, 97074, Wuerzburg, Germany
| | - D Rak
- Clinical Trial Unit, Orthopedic Department, University of Wuerzburg, Brettreichstrasse 11, 97074, Wuerzburg, Germany
| | - L Seefried
- Clinical Trial Unit, Orthopedic Department, University of Wuerzburg, Brettreichstrasse 11, 97074, Wuerzburg, Germany.
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Zhang Z, Nam HK, Crouch S, Hatch NE. Tissue Nonspecific Alkaline Phosphatase Function in Bone and Muscle Progenitor Cells: Control of Mitochondrial Respiration and ATP Production. Int J Mol Sci 2021; 22:ijms22031140. [PMID: 33498907 PMCID: PMC7865776 DOI: 10.3390/ijms22031140] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 01/17/2021] [Accepted: 01/20/2021] [Indexed: 12/23/2022] Open
Abstract
Tissue nonspecific alkaline phosphatase (TNAP/Alpl) is associated with cell stemness; however, the function of TNAP in mesenchymal progenitor cells remains largely unknown. In this study, we aimed to establish an essential role for TNAP in bone and muscle progenitor cells. We investigated the impact of TNAP deficiency on bone formation, mineralization, and differentiation of bone marrow stromal cells. We also pursued studies of proliferation, mitochondrial function and ATP levels in TNAP deficient bone and muscle progenitor cells. We find that TNAP deficiency decreases trabecular bone volume fraction and trabeculation in addition to decreased mineralization. We also find that Alpl−/− mice (global TNAP knockout mice) exhibit muscle and motor coordination deficiencies similar to those found in individuals with hypophosphatasia (TNAP deficiency). Subsequent studies demonstrate diminished proliferation, with mitochondrial hyperfunction and increased ATP levels in TNAP deficient bone and muscle progenitor cells, plus intracellular expression of TNAP in TNAP+ cranial osteoprogenitors, bone marrow stromal cells, and skeletal muscle progenitor cells. Together, our results indicate that TNAP functions inside bone and muscle progenitor cells to influence mitochondrial respiration and ATP production. Future studies are required to establish mechanisms by which TNAP influences mitochondrial function and determine if modulation of TNAP can alter mitochondrial respiration in vivo.
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Affiliation(s)
- Zhi Zhang
- Department of Natural Sciences, University of Michigan-Dearborn, 4901 Evergreen Rd, Dearborn, MI 48128, USA;
| | - Hwa Kyung Nam
- School of Dentistry, University of Michigan-Ann Arbor, 1011 N University Avenue, Ann Arbor, MI 48103, USA; (H.K.N.); (S.C.)
| | - Spencer Crouch
- School of Dentistry, University of Michigan-Ann Arbor, 1011 N University Avenue, Ann Arbor, MI 48103, USA; (H.K.N.); (S.C.)
| | - Nan E. Hatch
- School of Dentistry, University of Michigan-Ann Arbor, 1011 N University Avenue, Ann Arbor, MI 48103, USA; (H.K.N.); (S.C.)
- Correspondence: ; Tel.: +1-734-764-6567
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TNAP as a New Player in Chronic Inflammatory Conditions and Metabolism. Int J Mol Sci 2021; 22:ijms22020919. [PMID: 33477631 PMCID: PMC7831495 DOI: 10.3390/ijms22020919] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/14/2021] [Accepted: 01/14/2021] [Indexed: 12/19/2022] Open
Abstract
This review summarizes important information on the ectoenzyme tissue-nonspecific alkaline phosphatase (TNAP) and gives a brief insight into the symptoms, diagnostics, and treatment of the rare disease Hypophosphatasia (HPP), which is resulting from mutations in the TNAP encoding ALPL gene. We emphasize the role of TNAP beyond its well-known contribution to mineralization processes. Therefore, above all, the impact of the enzyme on central molecular processes in the nervous system and on inflammation is presented here.
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Chamakkala T, Gallagher T. Hypophosphatasia: A missed diagnosis. INTERNATIONAL JOURNAL OF ACADEMIC MEDICINE 2021. [DOI: 10.4103/ijam.ijam_72_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Seefried L, Kishnani PS, Moseley S, Denker AE, Watsky E, Whyte MP, Dahir KM. Pharmacodynamics of asfotase alfa in adults with pediatric-onset hypophosphatasia. Bone 2021; 142:115664. [PMID: 32987199 DOI: 10.1016/j.bone.2020.115664] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 09/11/2020] [Accepted: 09/23/2020] [Indexed: 12/31/2022]
Abstract
BACKGROUND Hypophosphatasia (HPP) is the rare, inherited, metabolic bone disease characterized by low activity of the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP) leading to excess extracellular inorganic pyrophosphate (PPi) and pyridoxal 5'-phosphate (PLP). Asfotase alfa is the human recombinant enzyme-replacement therapy that replaces deficient TNSALP. However, there is limited information concerning the appropriate dose of asfotase alfa for adult patients with pediatric-onset HPP. Thus, we evaluated the pharmacodynamics and safety/tolerability of different doses of asfotase alfa in such patients. METHODS This 13-week, Phase 2a, open-label study enrolled adults (aged ≥18 years) with pediatric-onset HPP. They were randomized 1:1:1 to receive a single subcutaneous dose of asfotase alfa (0.5, 2.0, or 3.0 mg/kg) at Week 1, then 3 times per week (ie, 1.5, 6.0, or 9.0 mg/kg/wk) starting at Week 3 for 7 weeks. Key outcome measures included change from Baseline to before the third dose during Week 9 (trough) in plasma PPi (primary outcome measure) and PLP (secondary outcome measure). RESULTS Twenty-seven adults received asfotase alfa 0.5 (n = 8), 2.0 (n = 10), and 3.0 (n = 9) mg/kg; all completed the study. Median (range) age was 45 (18-77) years; most patients were white (96%) and female (59%). Median plasma PPi and PLP concentrations decreased from Baseline to Week 9 in all 3 cohorts. Differences in least squares mean (LSM) changes in PPi were significant with 2.0 mg/kg (p = 0.0008) and 3.0 mg/kg (p < 0.0001) vs. 0.5 mg/kg. Differences in LSM changes in PLP were also significant for 2.0 mg/kg (p = 0.0239) and 3.0 mg/kg (p = 0.0128) vs. 0.5 mg/kg. Injection site reactions were the most frequent treatment-emergent adverse event (78%), showing increasing frequency with increasing dose. CONCLUSIONS Adults with pediatric-onset HPP receiving asfotase alfa at 6.0 mg/kg/wk (the recommended dose) or 9.0 mg/kg/wk had greater reductions in circulating PPi and PLP concentrations compared with a lower dose of 1.5 mg/kg/wk. TRIAL REGISTRATION Clinicaltrials.gov identifier NCT02797821.
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Affiliation(s)
- Lothar Seefried
- Orthopedic Department, University of Würzburg, Würzburg, Bavaria, Germany.
| | - Priya S Kishnani
- Department of Pediatrics, Duke University Medical Center, Durham, NC, USA
| | | | | | - Eric Watsky
- Alexion Pharmaceuticals, Inc., Boston, MA, USA
| | - Michael P Whyte
- Center for Metabolic Bone Disease and Molecular Research, Shriners Hospitals for Children-St. Louis, St. Louis, MO, USA; Division of Bone and Mineral Diseases, Department of Internal Medicine, Washington University School of Medicine at Barnes-Jewish Hospital, St Louis, MO, USA
| | - Kathryn M Dahir
- Program for Metabolic Bone Disorders at Vanderbilt, Division of Diabetes and Endocrinology, Vanderbilt University Medical Center, Nashville, TN, USA
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Kato M, Hattori T, Shimizu T, Ninagawa K, Izumihara R, Nomoto H, Tanimura K, Atsumi T. Intrafamilial phenotypic distinction of hypophosphatasia with identical tissue nonspecific alkaline phosphatase gene mutation: a family report. J Bone Miner Metab 2020; 38:903-907. [PMID: 32772198 DOI: 10.1007/s00774-020-01137-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Accepted: 07/30/2020] [Indexed: 10/23/2022]
Abstract
Hypophosphatasia (HPP) is caused by mutations in the tissue nonspecific alkaline phosphatase (TNSALP) gene in an autosomal recessive or dominant manner and characterized by defective mineralization of bone and low serum ALP levels. In this report, we present a family with HPP mother (case 1) and HPP child (case 2) who have identical TNSALP gene mutation (c.1015G>A p.Gly339Arg heterozygous mutation) but distinct clinical phenotypes. Whereas case 1 appeared to be asymptomatic despite extremely low levels of serum ALP, case 2 had several HPP-related symptoms, such as tooth loss, fractures, short stature, with slightly decreased ALP levels. Upon the diagnosis of HPP, case 1 discontinued denosumab, which was used to treat her rheumatoid arthritis, concerning the risk of atypical femoral fractures. The clinical course of this family was suggestive in a genotype-phenotype imbalance in HPP, the underdiagnosis of HPP in adults, and the risk of atypical femoral fractures using bone resorption inhibitors.
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Affiliation(s)
- Masaru Kato
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, N15W7, Kita-Ku, Sapporo, 060-8638, Japan.
| | | | - Tomohiro Shimizu
- Department of Orthopedic Surgery, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Keita Ninagawa
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, N15W7, Kita-Ku, Sapporo, 060-8638, Japan
| | - Rimi Izumihara
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, N15W7, Kita-Ku, Sapporo, 060-8638, Japan
| | - Hiroshi Nomoto
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, N15W7, Kita-Ku, Sapporo, 060-8638, Japan
| | | | - Tatsuya Atsumi
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, N15W7, Kita-Ku, Sapporo, 060-8638, Japan
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Martins L, Dos Santos EL, de Almeida AB, Machado RA, Lyrio AM, Foster BL, Kantovitz KR, Coletta RD, Nociti FH. A novel de novo heterozygous ALPL nonsense mutation associated with adult hypophosphatasia. Osteoporos Int 2020; 31:2251-2257. [PMID: 32572521 PMCID: PMC8214176 DOI: 10.1007/s00198-020-05490-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Accepted: 06/03/2020] [Indexed: 12/20/2022]
Abstract
UNLABELLED Using genetic, clinical, biochemical, and radiographic assessment and bioinformatic approaches, we present an unusual case of adult HPP caused by a novel de novo heterozygous nonsense mutation in the alkaline phosphatase (ALPL). INTRODUCTION Hypophosphatasia (HPP) is caused by genetic alterations of the ALPL gene, encoding the tissue-nonspecific isozyme of alkaline phosphatase (TNSALP). Here, the purpose was to perform clinical and molecular investigation in a 36-year-old Caucasian woman suspected to present adult HPP. METHODS Medical and dental histories were obtained for the proposita and family members, including biochemical, radiographic, and dental assessments. ALPL mutational analysis was performed by the Sanger sequencing method, and the functional impact prediction of the identified mutations was assessed by bioinformatic methods. RESULTS We identified a novel heterozygous nonsense mutation in the ALPL gene (NM_000478.6:c.768G>A; W[TGG]>*[TGA]) associated with spontaneous vertebral fracture, severe back pain, musculoskeletal pain, low bone density, and short-rooted permanent teeth loss. Functional prediction analysis revealed that the Trp256Ter mutation led to a complete loss of TNSALP crown domain and extensive loss of other functional domains (calcium-binding domain, active site vicinity, and zinc-binding site) and over 60% loss of homodimer interface residues, suggesting that the mutant TNSALP molecules are nonfunctional and form unstable homodimers. Genotyping of the ALPL in the proposita's parents, sister, and niece revealed that in this case, HPP occurred due to a de novo mutation. CONCLUSION The present study describes a novel genotype-phenotype and structure-function relationship for HPP, contributing to a better molecular comprehension of HPP etiology and pathophysiology.
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Affiliation(s)
- L Martins
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, State University of Campinas - UNICAMP, Av. Limeira, 901, Piracicaba, SP, 13414-903, Brazil
| | - E L Dos Santos
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, State University of Campinas - UNICAMP, Av. Limeira, 901, Piracicaba, SP, 13414-903, Brazil
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - A B de Almeida
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, State University of Campinas - UNICAMP, Av. Limeira, 901, Piracicaba, SP, 13414-903, Brazil
| | - R A Machado
- Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, SP, Brazil
- Hospital for Rehabilitation of Craniofacial Anomalies, University of São Paulo (HRAC/USP), Bauru, SP, Brazil
| | - A M Lyrio
- Pontifical Catholic University of Campinas, Campinas, SP, Brazil
| | - B L Foster
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - K R Kantovitz
- Department of Dental Materials, São Leopoldo Research Center, Campinas, SP, Brazil
| | - R D Coletta
- Department of Oral Diagnosis, Piracicaba Dental School, State University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - F H Nociti
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, State University of Campinas - UNICAMP, Av. Limeira, 901, Piracicaba, SP, 13414-903, Brazil.
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Seefried L, Dahir K, Petryk A, Högler W, Linglart A, Martos-Moreno GÁ, Ozono K, Fang S, Rockman-Greenberg C, Kishnani PS. Burden of Illness in Adults With Hypophosphatasia: Data From the Global Hypophosphatasia Patient Registry. J Bone Miner Res 2020; 35:2171-2178. [PMID: 32654183 DOI: 10.1002/jbmr.4130] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/23/2019] [Revised: 06/25/2020] [Accepted: 07/04/2020] [Indexed: 12/19/2022]
Abstract
Hypophosphatasia (HPP) is a rare, inherited, metabolic disease caused by deficient tissue non-specific alkaline phosphatase activity. This study aims to assess patient-reported pain, disability and health-related quality of life (HRQoL) in a real-world cohort of adults with HPP who were not receiving asfotase alfa during the analysis. Adults (≥18 years old) with HPP (confirmed by ALPL gene mutation and/or low serum alkaline phosphatase activity for age/sex) were identified from the Global HPP Registry (NCT02306720). Demographics, clinical characteristics, and data on patient-reported pain, disability, and HRQoL (assessed by Brief Pain Inventory Short Form [BPI-SF], Health Assessment Questionnaire Disability Index [HAQ-DI], and 36-Item Short-Form Health Survey version 2 [SF-36v2], respectively) were stratified by pediatric- and adult-onset HPP and summarized descriptively. Of the 304 adults included (median [min, max] age 48.6 [18.8, 79.8] years; 74% women), 45% had adult-onset HPP and 33% had pediatric-onset HPP (unknown age of onset, 22%). Of those with data, 38% had experienced ≥5 HPP manifestations and 62% had a history of ≥1 fracture/pseudofracture. Median (Q1, Q3) BPI-SF scores were 3.5 (1.5, 5.3) for pain severity and 3.3 (0.9, 6.2) for pain interference. Median (Q1, Q3) disability on the HAQ-DI was 0.3 (0.0, 0.7). Median (Q1, Q3) physical and mental component summary scores on the SF-36v2 were 42.4 (32.7, 49.9) and 45.3 (36.3, 54.8), respectively. Greater numbers of HPP manifestations experienced/body systems affected correlated significantly with poorer scores on the BPI-SF, HAQ-DI, and SF-36v2 (all p < 0.05). No significant differences between adults with pediatric- and adult-onset HPP were observed for patient-reported outcomes, except for disability and the BPI-SF question "pain at its worst," which were significantly higher among adults with pediatric- versus adult-onset HPP (p = 0.03 and 0.04, respectively). These data from the Global HPP Registry show that adults with HPP have a substantial burden of illness that is associated with reduced patient-reported HRQoL, regardless of age of disease onset. © 2020 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Lothar Seefried
- Orthopedic Department, University of Würzburg, Würzburg, Germany
| | - Kathryn Dahir
- Vanderbilt University Medical Center, Nashville, TN, USA
| | - Anna Petryk
- Alexion Pharmaceuticals, Inc., Boston, MA, USA
| | - Wolfgang Högler
- Department of Pediatrics and Adolescent Medicine, Johannes Kepler University Linz, Linz, Austria
| | - Agnès Linglart
- AP-HP Paris-Saclay, Endocrinology and Diabetes for Children, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, Filière OSCAR, Paris, France
| | - Gabriel Ángel Martos-Moreno
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, IIS La Princesa, Madrid, Spain.,Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain.,CIBERobn, ISCIII, Madrid, Spain
| | - Keiichi Ozono
- Department of Pediatrics, Graduate School of Medicine, Osaka University, Osaka, Japan
| | - Shona Fang
- Alexion Pharmaceuticals, Inc., Boston, MA, USA
| | | | - Priya S Kishnani
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC, USA
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Huggins E, Ong R, Rockman-Greenberg C, Flueckinger LB, Dahir KM, Kishnani PS. Multigenerational case examples of hypophosphatasia: Challenges in genetic counseling and disease management. Mol Genet Metab Rep 2020; 25:100661. [PMID: 33101980 PMCID: PMC7578550 DOI: 10.1016/j.ymgmr.2020.100661] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 12/19/2022] Open
Abstract
Hypophosphatasia (HPP) is an inherited metabolic condition caused by pathogenic mutations in the ALPL gene. This leads to deficiency of tissue non-specific alkaline phosphatase (TNSALP), resulting in decreased mineralization of the bones and/or teeth and multi-systemic complications. Inheritance may be autosomal dominant or recessive, and the phenotypic spectrum, including age of onset, varies widely. We present four families demonstrating both modes of inheritance of HPP and phenotypic variability and discuss the resultant challenges in disease management, genetic counseling, and risk assessment. Failure to consider different modes of inheritance in a family with HPP may lead to an inaccurate risk assessment upon which medical and reproductive decisions may be made. We highlight the essential role of high-quality genetic counseling and meaningful biochemical and molecular testing strategies in the evaluation and management of families with HPP.
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Affiliation(s)
- Erin Huggins
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC, USA
| | - Ricardo Ong
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC, USA
| | - Cheryl Rockman-Greenberg
- Department of Pediatrics and Child Health, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB, Canada
| | - Lauren Bailey Flueckinger
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC, USA
| | - Kathryn M Dahir
- Vanderbilt University Medical Center, Program for Metabolic Bone Disorders, Division of Endocrinology, Nashville, TN, USA
| | - Priya S Kishnani
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC, USA
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Genest F, Rak D, Petryk A, Seefried L. Physical Function and Health-Related Quality of Life in Adults Treated With Asfotase Alfa for Pediatric-Onset Hypophosphatasia. JBMR Plus 2020; 4:e10395. [PMID: 32995696 PMCID: PMC7507107 DOI: 10.1002/jbm4.10395] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 07/02/2020] [Accepted: 07/13/2020] [Indexed: 12/25/2022] Open
Abstract
Hypophosphatasia (HPP) is a rare, inherited, metabolic disease characterized by tissue-nonspecific alkaline phosphatase deficiency resulting in musculoskeletal and systemic clinical manifestations. This observational study evaluated the effectiveness of enzyme replacement therapy with asfotase alfa on physical function and health-related quality of life (HRQoL) among adults with pediatric-onset HPP who received asfotase alfa for 12 months at a single center (ClinicalTrial.gov no.: NCT03418389). Primary outcomes evaluated physical function with the 6-minute walk test (6MWT), timed up-and-go (TUG) test, Short Physical Performance Battery (SPPB), and handheld dynamometry (HHD). Secondary outcome measures included the Lower Extremity Functional Scale (LEFS), pain prevalence/intensity, and pain medication use; HRQoL was evaluated using the 36-Item Short-Form Health Survey version 2 (SF-36v2). Safety data were collected throughout the study. All 14 patients (11 women) had compound heterozygous ALPL gene mutations and ≥1 HPP bone manifestation, including history of ≥1 fracture. Mean (min, max) age was 51 (19 to 78) years. From baseline to 12 months of treatment, median 6MWT distance increased from 267 m to 320 m (n = 13; p = 0.023); median TUG test time improved from 14.4 s to 11.3 s (n = 9; p = 0.008). Specific components of the SPPB also improved significantly: median 4-m gait speed increased from 0.8 m/s to 1.1 m/s (n = 10; p = 0.007) and median repeated chair-rise time improved from 22 s to 13 s (n = 9; p = 0.008). LEFS score improved from 24 points to 53 points (n = 10; p = 0.002). Improvements in HHD were not clinically significant. SF-36v2 Physical Component Score (PCS) improved after 12 months of treatment (n = 9; p = 0.010). Pain level did not change significantly from baseline to 12 months of treatment. There were significant improvements on chair-rise time and SF-36v2 PCS by 3 months, and on TUG test time after 6 months. No new safety signals were identified. These results show the real-world effectiveness of asfotase alfa in improving physical functioning and HRQoL in adults with pediatric-onset HPP. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Franca Genest
- Orthopedic Department University of Würzburg Würzburg Germany
| | - Dominik Rak
- Orthopedic Department University of Würzburg Würzburg Germany
| | | | - Lothar Seefried
- Orthopedic Department University of Würzburg Würzburg Germany
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Bianchi ML, Bishop NJ, Guañabens N, Hofmann C, Jakob F, Roux C, Zillikens MC. Hypophosphatasia in adolescents and adults: overview of diagnosis and treatment. Osteoporos Int 2020; 31:1445-1460. [PMID: 32162014 DOI: 10.1007/s00198-020-05345-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 02/11/2020] [Indexed: 12/11/2022]
Abstract
This article provides an overview of the current knowledge on hypophosphatasia-a rare genetic disease of very variable presentation and severity-with a special focus on adolescents and adults. It summarizes the available information on the many known mutations of tissue-nonspecific alkaline phosphatase (TNSALP), the epidemiology and clinical presentation of the disease in adolescents and adults, and the essential diagnostic clues. The last section reviews the therapeutic approaches, including recent reports on enzyme replacement therapy (EnzRT).
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Affiliation(s)
- M L Bianchi
- Laboratorio sperimentale di ricerche sul metabolismo osseo infantile, Centro Malattie Metaboliche Ossee, Istituto Auxologico Italiano IRCCS, Milan, Italy.
| | - N J Bishop
- Department of Oncology and Metabolism, University of Sheffield, Sheffield Children's NHS Foundation Trust, Sheffield, UK
| | - N Guañabens
- Servicio de Reumatología, Hospital Clínic, Universidad de Barcelona, IDIBAPS CIBERehd, Barcelona, Spain
| | - C Hofmann
- Children's Hospital, University of Würzburg, Würzburg, Germany
| | - F Jakob
- Orthopedic Centre for Musculoskeletal Research, University of Würzburg, Würzburg, Germany
| | - C Roux
- INSERM U1153 APHP Centre, Université de Paris, Department of Rheumatology, Paris, France
| | - M C Zillikens
- Department of Internal Medicine, Endocrinology Section, Erasmus Medical Centre, Rotterdam, The Netherlands
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Kuehn K, Hahn A, Seefried L. Mineral Intake and Clinical Symptoms in Adult Patients with Hypophosphatasia. J Clin Endocrinol Metab 2020; 105:5851912. [PMID: 32502243 DOI: 10.1210/clinem/dgaa324] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 06/02/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND Hypophosphatasia (HPP) is a rare inherited metabolic disorder characterized by deficient activity of the tissue-nonspecific alkaline phosphatase entailing impaired turnover of phosphorus metabolites. Dietary mineral intake is suspected to influence clinical symptoms of HPP, but scientific evidence is missing. METHODS Cross-sectional matched-pairs study collecting comprehensive data on nutrient intake in 20 HPP patients and 20 unaffected, age- and gender-matched controls. Dietary information and clinical symptoms were documented in detail over 7 consecutive days using structured diaries. RESULTS Baseline data and type of energy-supplying nutrients were balanced between both groups. Median nutritional intake of phosphorus and calcium were significantly lower in HPP patients versus controls, which is partially attributable to lower energy consumption in HPP patients. Differences regarding phosphorus and calcium (Ca/P) ratio and uptake of magnesium, zinc, and vitamin B6 were not statistically significant. Both high (≥ 1375 mg/d) and low intakes (< 1100 mg/d) of phosphorus were significantly associated with an increased frequency of neuropsychiatric symptoms (P = 0.02). Similarly, very high and very low intake of calcium was significantly associated with musculoskeletal (P < 0.01), gastrointestinal (P = 0.02), and neuropsychiatric (P < 0.001) symptoms. An increased Ca/P ratio was associated with increased tiredness/fatigue (P < 0.01), whereas a decreased Ca/P was associated with gastrointestinal issues (P = 0.01). CONCLUSION Phosphorus and calcium intake seem reduced in HPP patients along with reduced total energy consumption. Particularly high as well as very low absolute or unbalanced phosphorus and calcium intake are associated with an increased frequency of clinical symptoms.
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Affiliation(s)
- Katinka Kuehn
- Faculty of Natural Science, Institute of Food Science and Human Nutrition, Leibniz University Hannover, Hannover, Germany
| | - Andreas Hahn
- Faculty of Natural Science, Institute of Food Science and Human Nutrition, Leibniz University Hannover, Hannover, Germany
| | - Lothar Seefried
- Clinical Trial Unit, Orthopedic Institute, Koenig-Ludwig-Haus, University of Wuerzburg, Wuerzburg, Germany
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Lefever E, Witters P, Gielen E, Vanclooster A, Meersseman W, Morava E, Cassiman D, Laurent MR. Hypophosphatasia in Adults: Clinical Spectrum and Its Association With Genetics and Metabolic Substrates. J Clin Densitom 2020; 23:340-348. [PMID: 30655187 DOI: 10.1016/j.jocd.2018.12.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Revised: 12/15/2018] [Accepted: 12/17/2018] [Indexed: 01/05/2023]
Abstract
BACKGROUND Hypophosphatasia (HPP) is a rare metabolic bone disorder caused by mutations in the alkaline phosphatase (ALPL) gene, and characterized by low circulating alkaline phosphatase (ALP) levels and bone, muscle, dental and systemic manifestations. In this case series we investigate the clinical spectrum, genetic and biochemical profile of adult HPP patients from the University Hospitals Leuven, Belgium. METHODOLOGY Adults with HPP were identified through medical record review. Inclusion criteria were: (1) age ≥ 16 yr; (2) consecutively low ALP levels not explained by secondary causes; (3) one or more of the following supporting criteria: biochemical evidence of elevated enzyme substrates; subtrochanteric fractures, metatarsal fractures or other typical clinical features; family history of HPP; a known or likely pathogenic ALPL mutation. RESULTS Nineteen patients met our inclusion criteria (n = 2 infantile, n = 6 childhood, n = 10 adult-onset HPP and one asymptomatic carrier). Fractures and dental abnormalities were the most reported symptoms. Fatigue was reported in n = 7/19 patients (37%), three of which had previously been misdiagnosed as having chronic fatigue syndrome and/or fibromyalgia. Empirical pyridoxine therapy in four patients (without seizures) did not provide symptomatic relief. N = 7/19 patients (37%) were inappropriately treated or planned to be treated with antiresorptive treatment. Two patients developed atypical femoral fractures following exposure to bisphosphonates and/or denosumab. Patients detected by screening were less severely affected, while patients with homozygous or compound heterozygous mutations had the most severe symptoms, significantly lower circulating ALP levels (p = 0.013) and significantly higher pyridoxal-5'-phosphate (p = 0.0018) and urinary phosphoethanolamine (p = 0.0001) concentrations. CONCLUSIONS Screening may detect mainly less severely affected individuals, which may nevertheless avoid misdiagnosis and inappropriate antiresorptive drug exposure. Patients with biallelic mutations had more severe symptoms, significantly lower ALP and higher substrate levels. Whether the latter finding has implications for the classification and treatment of HPP should be investigated further in larger cohorts.
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Affiliation(s)
- Eveline Lefever
- Department of Internal Medicine, University Hospitals Leuven, Leuven, Belgium
| | - Peter Witters
- Centre for Metabolic Diseases, University Hospitals Leuven, Leuven, Belgium; Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - Evelien Gielen
- Center for Metabolic Bone Diseases, University Hospitals Leuven, Leuven, Belgium; Department of Chronic Diseases, Metabolism and Aging (CHROMETA), KU Leuven, Leuven, Belgium
| | - Annick Vanclooster
- Centre for Metabolic Diseases, University Hospitals Leuven, Leuven, Belgium
| | - Wouter Meersseman
- Centre for Metabolic Diseases, University Hospitals Leuven, Leuven, Belgium
| | - Eva Morava
- Centre for Metabolic Diseases, University Hospitals Leuven, Leuven, Belgium; Hayward Genetics Center, Tulane University Medical School, New Orleans, LA, USA; Clinical Genomics Department, Mayo Clinic, Rochester, MN, USA
| | - David Cassiman
- Centre for Metabolic Diseases, University Hospitals Leuven, Leuven, Belgium; Department of Chronic Diseases, Metabolism and Aging (CHROMETA), KU Leuven, Leuven, Belgium
| | - Michaël R Laurent
- Center for Metabolic Bone Diseases, University Hospitals Leuven, Leuven, Belgium; Department of Chronic Diseases, Metabolism and Aging (CHROMETA), KU Leuven, Leuven, Belgium.
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71
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Tilden DR, Sheehan JH, Newman JH, Meiler J, Capra JA, Ramirez A, Simmons J, Dahir K. Phenotypic Profiling in Subjects Heterozygous for 1 of 2 Rare Variants in the Hypophosphatasia Gene ( ALPL). J Endocr Soc 2020; 4:bvaa084. [PMID: 32803091 PMCID: PMC7417882 DOI: 10.1210/jendso/bvaa084] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Accepted: 06/22/2020] [Indexed: 11/19/2022] Open
Abstract
Context Hypophosphatasia (HPP) is a syndrome marked by low serum alkaline phosphatase (AlkP) activity as well as musculoskeletal and/or dental disease. While the majority of subjects with HPP carry a pathogenic variant in the ALPL gene or its regulatory regions, individual pathogenic variants are often not tightly correlated with clinical symptomatology. We sought to better understand the genotype/phenotype correlation in HPP by examining the clinical and biochemical data of 37 subjects with 2 rare variants in ALPL. Methods Through BioVU, a DNA biobank that pairs individuals’ genetic information with their de-identified medical records, we identified subjects with 2 rare variants with distinct reported clinical phenotypes (p.D294A and p.T273M). We then performed a manual review of these subjects’ de-identified medical records along with computational modeling of protein structure to construct a genetic, biochemical and clinical phenotype for each subject and variant. Results Twenty subjects with the p.D294A variant and 17 with the p.T273M variant had sufficient data for analysis. Among subjects in our cohort with the p.D294A variant, 6 (30.0%) had both clinical bone disease and serum AlkP activity below 40 IU/L while 4 subjects (23.5%) with the p.T273M variant met the same criteria despite the distinct clinical phenotypes of these variants. Conclusions Given the loose genotype/phenotype correlation in HPP seen in our cohort, clinical context is crucial for the interpretation of genetic test results to guide clinical care in this population. Otherwise, over- or under-diagnosis may occur, resulting in misidentification of those who may benefit from additional screening and perhaps pharmacologic intervention.
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Affiliation(s)
- Daniel R Tilden
- Division of Endocrinology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee.,Ian M. Burr Division of Pediatric Endocrinology, Department of Pediatrics, Monroe Carroll Jr. Children's Hospital at Vanderbilt, Nashville, Tennessee
| | - Jonathan H Sheehan
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - John H Newman
- Division of Allergy, Pulmonary and Critical Care Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jens Meiler
- Center for Structural Biology, Vanderbilt University Medical Center Nashville, TN.,Department of Chemistry, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Pharmacology, Vanderbilt University Medical Center, Nashville, Tennessee
| | - John A Capra
- Center for Structural Biology, Vanderbilt University Medical Center Nashville, TN.,Department of Chemistry, Vanderbilt University Medical Center, Nashville, Tennessee.,Department of Biological Sciences and Biomedical Informatics, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Andrea Ramirez
- Division of Endocrinology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jill Simmons
- Ian M. Burr Division of Pediatric Endocrinology, Department of Pediatrics, Monroe Carroll Jr. Children's Hospital at Vanderbilt, Nashville, Tennessee
| | - Kathryn Dahir
- Division of Endocrinology, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee
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72
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Abstract
Beyond its functions in locomotion, support and protection of vital organs, bone also interacts with other organs to adjust mineral balance in response to physiological requirements. Bone remodelling is a continuous process of bone resorption and formation for the purpose of maintaining healthy bone mass and growth. Any derangement in this process can cause bone disorders with important clinical consequences. The most prominent features of bone diseases in children include early bone fractures, deformities and pain, which can persist and worsen later in life if an accurate and timely diagnosis is not achieved. Biochemical and genetic testing usually help to discriminate the aetiology of the disease, which determines the subsequent management and follow-up. This review focuses on major genetic metabolic bone diseases in children, their pathophysiological mechanisms, the potential therapeutic interventions and the possible consequences in adulthood of the disease and its treatments.
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Affiliation(s)
- Carlos Gómez-Alonso
- Unidad de Gestión Clínica de Metabolismo Óseo y Mineral, Instituto Reina Sofía de Investigación, RedinRen ISCIII, Hospital Universitario Central de Asturias, Universidad de Oviedo, Oviedo, Spain.
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73
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Alonso N, Larraz-Prieto B, Berg K, Lambert Z, Redmond P, Harris SE, Deary IJ, Pugh C, Prendergast J, Ralston SH. Loss-of-Function Mutations in the ALPL Gene Presenting with Adult Onset Osteoporosis and Low Serum Concentrations of Total Alkaline Phosphatase. J Bone Miner Res 2020; 35:657-661. [PMID: 31793067 PMCID: PMC9328664 DOI: 10.1002/jbmr.3928] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 11/11/2019] [Accepted: 11/23/2019] [Indexed: 12/13/2022]
Abstract
Hypophosphatasia (HPP) is a rare inherited disorder characterized by rickets and low circulating concentrations of total alkaline phosphatase (ALP) caused by mutations in ALPL. Severe HPP presents in childhood but milder forms can present in adulthood. The prevalence and clinical features of adult HPP are poorly defined. The aim of this study was to evaluate the prevalence and clinical significance of low serum total alkaline phosphatase (ALP) levels in a clinic-based population of adult osteoporotic patients. We searched for patients with low ALP in a cohort of 3285 patients referred to an osteoporosis clinic over a 10-year period and performed mutation screening of ALPL in those with low ALP (≤40 U/L) on two or more occasions. These individuals were matched with four clinic controls with a normal ALP. We also evaluated the prevalence of low ALP and ALPL mutations in 639 individuals from the general population from the same region. We identified 16/3285 (0.49%) clinic patients with low ALP and 14 (87.5%) had potentially pathogenic variants in ALPL. Eight of these individuals were heterozygous for mutations previously described in HPP and 2 were heterozygous for novel mutations (p.Arg301Trp and p.Tyr101X). These mutations were not found in clinic controls or in the general population. Eight patients with low ALP, including 4 with ALPL mutations, were treated with bisphosphonates for an average of 6.5 years. In these individuals, the rate of fractures during treatment was comparable to that in normal ALP clinic controls who were treated with bisphosphonates. We conclude that heterozygous loss-of-function mutations in ALPL are common in osteoporosis patients with low ALP. Further studies are required to determine how best these individuals should be treated. © 2019 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research.
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Affiliation(s)
- Nerea Alonso
- Rheumatology and Bone Disease Unit, Centre for Genomic and Experimental Medicine, MRC institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Beatriz Larraz-Prieto
- Rheumatology and Bone Disease Unit, Centre for Genomic and Experimental Medicine, MRC institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Kathryn Berg
- Rheumatology and Bone Disease Unit, Centre for Genomic and Experimental Medicine, MRC institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Zoe Lambert
- Rheumatology and Bone Disease Unit, Centre for Genomic and Experimental Medicine, MRC institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Paul Redmond
- Department of Psychology, University of Edinburgh, Edinburgh, UK
| | - Sarah E Harris
- Department of Psychology, University of Edinburgh, Edinburgh, UK.,Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
| | - Ian J Deary
- Department of Psychology, University of Edinburgh, Edinburgh, UK.,Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh, UK
| | - Carys Pugh
- Division of Psychiatry, University of Edinburgh, Royal Edinburgh Hospital, Edinburgh, UK
| | - James Prendergast
- Genetics and Genomics Division, The Roslin Institute, University of Edinburgh, Midlothian, UK
| | - Stuart H Ralston
- Rheumatology and Bone Disease Unit, Centre for Genomic and Experimental Medicine, MRC institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
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74
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del Angel G, Reynders J, Negron C, Steinbrecher T, Mornet E. Large-scale in vitro functional testing and novel variant scoring via protein modeling provide insights into alkaline phosphatase activity in hypophosphatasia. Hum Mutat 2020; 41:1250-1262. [PMID: 32160374 PMCID: PMC7317754 DOI: 10.1002/humu.24010] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 02/05/2020] [Accepted: 03/04/2020] [Indexed: 01/20/2023]
Abstract
Hypophosphatasia (HPP) is a rare metabolic disorder characterized by low tissue‐nonspecific alkaline phosphatase (TNSALP) typically caused by ALPL gene mutations. HPP is heterogeneous, with clinical presentation correlating with residual TNSALP activity and/or dominant‐negative effects (DNE). We measured residual activity and DNE for 155 ALPL variants by transient transfection and TNSALP enzymatic activity measurement. Ninety variants showed low residual activity and 24 showed DNE. These results encompass all missense variants with carrier frequencies above 1/25,000 from the Genome Aggregation Database. We used resulting data as a reference to develop a new computational algorithm that scores ALPL missense variants and predicts high/low TNSALP enzymatic activity. Our approach measures the effects of amino acid changes on TNSALP dimer stability with a physics‐based implicit solvent energy model. We predict mutation deleteriousness with high specificity, achieving a true‐positive rate of 0.63 with false‐positive rate of 0, with an area under receiver operating curve (AUC) of 0.9, better than all in silico predictors tested. Combining this algorithm with other in silico approaches can further increase performance, reaching an AUC of 0.94. This study expands our understanding of HPP heterogeneity and genotype/phenotype relationships with the aim of improving clinical ALPL variant interpretation.
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Affiliation(s)
- Guillermo del Angel
- Data Sciences, Genomics, and BioinformaticsAlexion Pharmaceuticals, Inc.BostonMassachusetts
| | - John Reynders
- Data Sciences, Genomics, and BioinformaticsAlexion Pharmaceuticals, Inc.BostonMassachusetts
| | | | | | - Etienne Mornet
- Laboratoire de Génétique Constitutionnelle Prénatale et PostnataleCentre Hospitalier de VersaillesLe ChesnayFrance
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75
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Koyama H, Yasuda S, Kakoi S, Ohata Y, Shimizu Y, Hasegawa C, Hayakawa A, Akiyama T, Yagi T, Aotani D, Imaeda K, Ozono K, Kataoka H, Tanaka T. Effect of Asfotase Alfa on Muscle Weakness in a Japanese Adult Patient of Hypophosphatasia with Low ALP Levels. Intern Med 2020; 59:811-815. [PMID: 31787692 PMCID: PMC7118397 DOI: 10.2169/internalmedicine.3298-19] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
A 40-year-old Japanese woman presented to our hospital with general fatigue and muscle weakness. She had a history of premature loss of deciduous teeth at 4 years old, her serum alkaline phosphatase (ALP) activity was as low as 91 U/L, and radiologic studies revealed thoracic deformity and sacroiliac calcification. Genetic sequencing revealed a heterozygous c.1559delT mutation in the tissue non-specific alkaline phosphatase gene (ALPL). Based on these findings, she was diagnosed with hypophosphatasia (HPP), and treatment with asfotase alfa, a recombinant human tissue-nonspecific alkaline phosphatase (TNSALP), was initiated. After six months of treatment with asfotase alfa, improvements were observed in the SF-36 score, six-minute walk distance, and grasping power. Although the overdiagnosis needs to be avoided, HPP should be considered in patients with undiagnosed musculoskeletal symptoms and a low serum ALP activity.
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Affiliation(s)
- Hiroyuki Koyama
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
| | - Satoshi Yasuda
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
| | - Shota Kakoi
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
| | - Yasuhisa Ohata
- Department of Pediatrics, Osaka University Graduate School of Medicine, Japan
| | - Yuki Shimizu
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
| | - Chie Hasegawa
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
| | - Akiko Hayakawa
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
| | - Tomoyuki Akiyama
- Department of Child Neurology, Okayama University Graduate School of Medicine, Japan
| | - Takashi Yagi
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
| | - Daisuke Aotani
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
| | - Kenro Imaeda
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
- Department of Endocrinology and Diabetes, Nagoya City West Medical Center, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University Graduate School of Medicine, Japan
| | - Hiromi Kataoka
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
| | - Tomohiro Tanaka
- Department of Gastroenterology and Metabolism, Nagoya City University Graduate School of Medical Science, Japan
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Baumbach SF, Pfahler V, Bechtold-Dalla Pozza S, Feist-Pagenstert I, Fürmetz J, Baur-Melnyk A, Stumpf UC, Saller MM, Straube A, Schmidmaier R, Leipe J. How We Manage Bone Marrow Edema-An Interdisciplinary Approach. J Clin Med 2020; 9:jcm9020551. [PMID: 32085459 PMCID: PMC7074543 DOI: 10.3390/jcm9020551] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 01/21/2020] [Accepted: 02/03/2020] [Indexed: 12/11/2022] Open
Abstract
Bone marrow edema (BME) is a descriptive term for a common finding in magnetic resonance imaging (MRI). Although pain is the major symptom, BME differs in terms of its causal mechanisms, underlying disease, as well as treatment and prognosis. This complexity together with the lack of evidence-based guidelines, frequently makes the identification of underlying conditions and its management a major challenge. Unnecessary multiple consultations and delays in diagnosis as well as therapy indicate a need for interdisciplinary clinical recommendations. Therefore, an interdisciplinary task force was set up within our large osteology center consisting of specialists from internal medicine, endocrinology/diabetology, hematology/oncology, orthopedics, pediatrics, physical medicine, radiology, rheumatology, and trauma surgery to develop a consenus paper. After review of literature, review of practical experiences (expert opinion), and determination of consensus findings, an overview and an algorithm were developed with concise summaries of relevant aspects of the respective underlying disease including diagnostic measures, clinical features, differential diagnosis and treatment of BME. Together, our single-center consensus review on the management of BME may help improve the quality of care for these patients.
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Affiliation(s)
- Sebastian F. Baumbach
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Department of General, Trauma and Reconstructive Surgery, University Hospital, Ludwig-Maximilians-University Munich, Nussbaumstraße 20, 80336 Munich, Germany
| | - Vanessa Pfahler
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Department of Radiology, University Hospital, Ludwig-Maximilians-University Munich, Marchioninistraße 15, 81377 Munich, Germany
| | - Susanne Bechtold-Dalla Pozza
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Department of Pediatric Endocrinology and Diabetology, University Hospital, Ludwig-Maximilians-University Munich, Lindwurmstraße 4, 80337 Munich, Germany
| | - Isa Feist-Pagenstert
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Department of Orthopaedic Surgery, Physical Medicine and Rehabilitation, University Hospital, Ludwig-Maximilians-University Munich, Marchioninistraße 15, 81377 Munich, Germany
| | - Julian Fürmetz
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Department of General, Trauma and Reconstructive Surgery, University Hospital, Ludwig-Maximilians-University Munich, Nussbaumstraße 20, 80336 Munich, Germany
| | - Andrea Baur-Melnyk
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Department of Radiology, University Hospital, Ludwig-Maximilians-University Munich, Marchioninistraße 15, 81377 Munich, Germany
| | - Ulla C. Stumpf
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Department of General, Trauma and Reconstructive Surgery, University Hospital, Ludwig-Maximilians-University Munich, Nussbaumstraße 20, 80336 Munich, Germany
| | - Maximilian M. Saller
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Department of General, Trauma and Reconstructive Surgery, University Hospital, Ludwig-Maximilians-University Munich, Nussbaumstraße 20, 80336 Munich, Germany
- Experimental Surgery and Regenerative Medicine (ExperiMed), Department of General, Trauma and Reconstructive Surgery, Ludwig-Maximilians-University (LMU), Fraunhoferstraße 20, 82152 Planegg-Martinsried, Germany
| | - Andreas Straube
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Department of Neurology, University Hospital, Ludwig-Maximilians-University Munich, Marchioninistraße 15, 81377 Munich, Germany
| | - Ralf Schmidmaier
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Department for Endocrinology and Diabetology, Department of Internal Medicine IV, Ludwig-Maximilians-University Munich, Ziemssenstraße 1, 80336 Munich, Germany
- Correspondence: (R.S.); (J.L.); Tel.: +49-89-4400-52101 (R.S.); Fax: +49-89-4400-54410 (R.S.)
| | - Jan Leipe
- Comprehensive Osteology Center Munich, University Hospital, Ludwig-Maximilians-University Munich, 80336 Munich, Germany; (S.F.B.); (V.P.); (S.B.-D.P.); (I.F.-P.); (J.F.); (A.B.-M.); (U.C.S.); (M.M.S.); (A.S.)
- Division of Rheumatology and Clinical Immunology, Department of Internal Medicine IV, Ludwig-Maximilians-University Munich, Ziemssenstraße 1, 80336 Munich, Germany
- Division of Rheumatology, Department of Medicine V, University Hospital Mannheim, Medical Faculty Mannheim of the University Heidelberg, Ludolf-Krehl-Straße 13–17, 68167 Mannheim, Germany
- Correspondence: (R.S.); (J.L.); Tel.: +49-89-4400-52101 (R.S.); Fax: +49-89-4400-54410 (R.S.)
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Tornero C, Navarro-Compán V, Tenorio JA, García-Carazo S, Buño A, Monjo I, Plasencia-Rodriguez C, Iturzaeta JM, Lapunzina P, Heath KE, Balsa A, Aguado P. Can we identify individuals with an ALPL variant in adults with persistent hypophosphatasaemia? Orphanet J Rare Dis 2020; 15:51. [PMID: 32066479 PMCID: PMC7026995 DOI: 10.1186/s13023-020-1315-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 01/24/2020] [Indexed: 12/19/2022] Open
Abstract
Background Hypophosphatasia (HPP) is an inborn error of metabolism characterized by low levels of serum alkaline phosphatase (ALP). Scarce evidence exists about features that should signal the potential association between hypophosphatasaemia and HPP in adults. The aim of this study is to estimate the prevalence of ALPL variants in subjects with persistent hypophosphatasaemia and determine the associated clinical and laboratory features. For this cross-sectional study, laboratory records of 386,353 subjects were screened by measurement of ALP activity. A total of 85 (0.18%) subjects with persistent hypophosphatasaemia (≥2 serum alkaline phosphatase–ALP–measurements ≤35 IU/L and none > 45 IU/L) were included (secondary causes previously discarded). ALPL genetic testing and a systematized questionnaire to retrieve demographic, clinical and laboratory data were performed. Descriptive analysis and logistic regression models were employed to identify the clinical and laboratory characteristics associated with ALPL variants. Results Forty subjects (47%) had a variant(s) in ALPL. With regard to clinical characteristics, the presence of an ALPL variant was significantly associated only with musculoskeletal pain (OR: 7.6; 95% IC: 1.9–30.9). Nevertheless, a trend to present more dental abnormalities (OR: 3.6; 95% IC: 0.9–13.4) was observed. Metatarsal stress fractures were also more frequent (4 vs 0; p < 0.05) in this group. Regarding laboratory features, median ALP levels were lower in subjects with ALPL variants (26 vs 29 IU/L; p < 0.005). Interestingly, the threshold of ALP levels < 25 IU/L showed a specificity, positive predictive value and positive likelihood ratio of 97.8, 94.4% and 19.8 to detect a positive ALPL test, respectively. Conclusions In subjects with persistent hypophosphatasaemia –secondary causes excluded– one out of two presented ALPL variants. Musculoskeletal pain and ALP levels < 25 IU/L are associated with this variant(s). In this scenario, ALP levels < 25 IU/L seem to be very useful to identify individuals with the presence of an ALPL variant.
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Affiliation(s)
- C Tornero
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain.
| | - V Navarro-Compán
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| | - J A Tenorio
- Institute of Medical and Molecular Genetics (INGEMM), La Paz University Hospital, IdiPAZ, Universidad Autónoma de Madrid, Madrid, Spain.,CIBERER (Centro de Investigación Biomédica en Red de Enfermedades Raras), ISCIII, Madrid, Spain
| | - S García-Carazo
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| | - A Buño
- Department of Clinical Biochemistry, La Paz University Hospital, Madrid, Spain
| | - I Monjo
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| | - C Plasencia-Rodriguez
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| | - J M Iturzaeta
- Department of Clinical Biochemistry, La Paz University Hospital, Madrid, Spain
| | - P Lapunzina
- Institute of Medical and Molecular Genetics (INGEMM), La Paz University Hospital, IdiPAZ, Universidad Autónoma de Madrid, Madrid, Spain.,CIBERER (Centro de Investigación Biomédica en Red de Enfermedades Raras), ISCIII, Madrid, Spain
| | - K E Heath
- Institute of Medical and Molecular Genetics (INGEMM), La Paz University Hospital, IdiPAZ, Universidad Autónoma de Madrid, Madrid, Spain.,CIBERER (Centro de Investigación Biomédica en Red de Enfermedades Raras), ISCIII, Madrid, Spain.,Skeletal dysplasia multidisciplinary Unit (UMDE), La Paz University Hospital, Madrid, Spain
| | - A Balsa
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
| | - P Aguado
- Department of Rheumatology, La Paz University Hospital, IdiPAZ, Paseo de la Castellana, 261, 28046, Madrid, Spain
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78
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Bhadada SK, Pal R, Dhiman V, Alonso N, Ralston SH, Kaur S, Gupta R. Adult hypophosphatasia with a novel ALPL mutation: Report of an Indian kindred. Bone Rep 2020; 12:100247. [PMID: 32025537 PMCID: PMC6997823 DOI: 10.1016/j.bonr.2020.100247] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2019] [Revised: 01/03/2020] [Accepted: 01/21/2020] [Indexed: 01/25/2023] Open
Abstract
Hypophosphatasia is an inborn error in metabolism characterized by low serum alkaline phosphatase (ALP) activity resulting from deactivating mutations in TNSALP (also known as ALPL), the gene that encodes the ‘tissue-specific’ isoenzyme of ALP. The disease exhibits significant clinical heterogeneity that spans from death in utero to only dental complications in adult life. Herein, we report a 47-year-old woman presenting with fracture of shaft of left femur. She had been complaining of pain in both of her thighs for the past 3 years. In addition, she gave a history of premature loss of teeth. Review of old radiographs revealed pseudo-fractures involving the lateral cortices of the femora on both sides. Biochemical panel revealed hyperphosphatemia, persistently low total alkaline phosphatase (ALP) and low-normal bone turnover markers. Screening of her siblings revealed low ALP in her younger sister and brother who were otherwise free from any major dento-arthro-osseous complaints. Sanger sequencing showed a novel, heterozygous, missense mutation in exon 5 at position 311 (c.311a > g;p.104 Asn > Ser) of ALPL gene in the three members. The patient underwent open reduction and intramedullary nailing of left femur along with prophylactic nailing on right side. This case report represents the first genetically confirmed kindred of adult hypophosphatasia from the Indian subcontinent.
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Affiliation(s)
- Sanjay K Bhadada
- Department of Endocrinology, Post Graduate Institute of Medical Education and Research, Chandigarh, India-160012
| | - Rimesh Pal
- Department of Endocrinology, Post Graduate Institute of Medical Education and Research, Chandigarh, India-160012
| | - Vandana Dhiman
- Department of Endocrinology, Post Graduate Institute of Medical Education and Research, Chandigarh, India-160012
| | - Nerea Alonso
- Rheumatology and Bone Disease Unit, Centre for Genomic and Experimental Medicine, IGMM, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU
| | - Stuart H Ralston
- Rheumatology and Bone Disease Unit, Centre for Genomic and Experimental Medicine, IGMM, University of Edinburgh, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU
| | - Simran Kaur
- Department of Endocrinology, Post Graduate Institute of Medical Education and Research, Chandigarh, India-160012
| | - Rajat Gupta
- Department of Diabetes and Endocrinology, Alchemist Hospital, Panchkula 134112, India
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Michigami T, Ohata Y, Fujiwara M, Mochizuki H, Adachi M, Kitaoka T, Kubota T, Sawai H, Namba N, Hasegawa K, Fujiwara I, Ozono K. Clinical Practice Guidelines for Hypophosphatasia. Clin Pediatr Endocrinol 2020; 29:9-24. [PMID: 32029969 PMCID: PMC6958520 DOI: 10.1297/cpe.29.9] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 08/16/2019] [Indexed: 12/17/2022] Open
Abstract
Hypophosphatasia (HPP) is a rare bone disease caused by inactivating mutations in the
ALPL gene, which encodes tissue-nonspecific alkaline phosphatase
(TNSALP). Patients with HPP have varied clinical manifestations and are classified based
on the age of onset and severity. Recently, enzyme replacement therapy using bone-targeted
recombinant alkaline phosphatase (ALP) has been developed, leading to improvement in the
prognosis of patients with life-threatening HPP. Considering these recent advances,
clinical practice guidelines have been generated to provide physicians with guides for
standard medical care for HPP and to support their clinical decisions. A task force was
convened for this purpose, and twenty-one clinical questions (CQs) were formulated,
addressing the issues of clinical manifestations and diagnosis (7 CQs) and those of
management and treatment (14 CQs). A systematic literature search was conducted using
PubMed/MEDLINE, and evidence-based recommendations were developed. The guidelines have
been modified according to the evaluations and suggestions from the Clinical Guideline
Committee of The Japanese Society for Pediatric Endocrinology (JSPE) and public comments
obtained from the members of the JSPE and a Japanese HPP patient group, and then approved
by the Board of Councils of the JSPE. We anticipate that the guidelines will be revised
regularly and updated.
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Affiliation(s)
- Toshimi Michigami
- Department of Bone and Mineral Research, Research Institute, Osaka Women's and Children's Hospital, Osaka Prefectural Hospital Organization, Osaka, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Yasuhisa Ohata
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Makoto Fujiwara
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Hiroshi Mochizuki
- Division of Endocrinology and Metabolism, Saitama Children's Medical Center, Saitama, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Masanori Adachi
- Department of Endocrinology and Metabolism, Kanagawa Children's Medical Center, Kanagawa, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Taichi Kitaoka
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Takuo Kubota
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Hideaki Sawai
- Department of Obstetrics and Gynecology, Hyogo College of Medicine, Hyogo, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Noriyuki Namba
- Division of Pediatrics and Perinatology, Tottori University Faculty of Medicine, Tottori, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Kosei Hasegawa
- Department of Pediatrics, Okayama University Hospital, Okayama, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Ikuma Fujiwara
- Department of Pediatrics, Sendai City Hospital, Miyagi, Japan.,Task Force for Hypophosphatasia Guidelines
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University Graduate School of Medicine, Osaka, Japan.,Task Force for Hypophosphatasia Guidelines
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Khan AA, Josse R, Kannu P, Villeneuve J, Paul T, Van Uum S, Greenberg CR. Hypophosphatasia: Canadian update on diagnosis and management. Osteoporos Int 2019; 30:1713-1722. [PMID: 30915507 DOI: 10.1007/s00198-019-04921-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Accepted: 02/27/2019] [Indexed: 12/22/2022]
Abstract
UNLABELLED Hypophosphatasia (HPP) is a rare inherited disorder of bone and mineral metabolism caused by loss of function mutations in the ALPL gene. The presentation in children and adults can be extremely variable and natural history is poorly understood particularly in adults. Careful patient evaluation is required with consideration of pharmacologic intervention in individuals meeting criteria for therapy. INTRODUCTION The purposes of this review are to present current evidence regarding the diagnosis and management of hypophosphatasia in children and adults and provide evidence-based recommendations for management. METHOD A MEDLINE, EMBASE, and Cochrane database search and literature review was completed. The following consensus recommendations were developed based on the highest level of evidence as well as expert opinion. RESULTS Hypophosphatasia is a rare inherited disorder of bone and mineral metabolism due to loss of function mutations in the tissue non-specific alkaline phosphatase (ALPL) gene causing reductions in the activity of the tissue non-specific isoenzyme of alkaline phosphatase (TNSALP). Deficient levels of alkaline phosphatase result in elevation of inhibitors of mineralization of the skeleton and teeth, principally inorganic pyrophosphate. The impaired skeletal mineralization may result in elevations in serum calcium and phosphate. Clinical features include premature loss of teeth, metatarsal and subtrochanteric fractures as well as fragility fractures. Poor bone healing post fracture has been observed. Myalgias and muscle weakness may also be present. In infancy and childhood, respiratory and neurologic complications can occur. CONCLUSIONS HPP is associated with significant morbidity and mortality. Pharmacologic intervention can result in significant clinical improvement. This Canadian position paper provides an overview of the musculoskeletal, renal, dental, respiratory, and neurologic manifestations of hypophosphatasia. The current state of the art in the diagnosis and management of hypophosphatasia is presented.
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Affiliation(s)
- A A Khan
- McMaster University, 1280 Main St W, Hamilton, ON, L8S 4L8, Canada.
| | - R Josse
- St. Michael's Hospital and University of Toronto , Toronto, Canada
| | - P Kannu
- Hospital for Sick Kids , Toronto, Canada
| | - J Villeneuve
- Le Centre Hospitalier Universitaire de Quebec, Quebec, Canada
| | - T Paul
- St. Joseph's Health Care London, London, Ontario, Canada
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Schmidt T, Rolvien T, Linke C, Jandl NM, Oheim R, Amling M, Barvencik F. Outcome of Teriparatide Treatment on Fracture Healing Complications and Symptomatic Bone Marrow Edema in Four Adult Patients With Hypophosphatasia. JBMR Plus 2019; 3:e10215. [PMID: 31485555 PMCID: PMC6715780 DOI: 10.1002/jbm4.10215] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 05/23/2019] [Accepted: 06/24/2019] [Indexed: 12/12/2022] Open
Abstract
The response to teriparatide has been described in very few cases of hypophosphatasia (HPP). In this cross‐sectional study, we report the prevalence of symptomatic bone marrow edema (BME) and fracture healing complications in a large cohort of childhood and adult HPP patients and discuss the results of teriparatide treatment in four cases. From 2016 to 2018, 51 patients with a diagnosis of HPP were seen at our institution. The diagnosis of HPP was established by low serum alkaline phosphatase (ALP), elevated serum pyridoxal‐5‐phosphate (PLP), at least one typical clinical symptom of HPP and supported by ALPL mutation analysis. In this study cohort, 28 (56%) and 14 (27%) patients had a history of fracture or a history of BME, respectively. Four patients, including middle‐aged to elderly women and men who all presented with persistent symptomatic BME or fracture healing complications, were treated with teriparatide. DXA was performed prior to treatment and laboratory values were measured on a regular basis during treatment. Treatment with teriparatide showed variable effects in terms of clinical and biochemical response. Although all four patients displayed a temporary increase in ALP activity, only two patients with a mild form of adult HPP and moderately increased PLP levels showed definite clinical and radiological improvement after teriparatide treatment. In conclusion, fracture healing complications and BME occur frequently in HPP patients. Teriparatide shows variable clinical and biochemical effects depending on the severity of the disease. PLP levels and the number of ALPL alleles might be good parameters to predict treatment outcomes. © 2019 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research
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Affiliation(s)
- Tobias Schmidt
- Department of Osteology and Biomechanics University Medical Center Hamburg-Eppendorf Hamburg Germany
| | - Tim Rolvien
- Department of Osteology and Biomechanics University Medical Center Hamburg-Eppendorf Hamburg Germany.,Department of Orthopedics University Medical Center Hamburg-Eppendorf Hamburg Germany
| | - Carolin Linke
- Department of Osteology and Biomechanics University Medical Center Hamburg-Eppendorf Hamburg Germany
| | - Nico Maximilian Jandl
- Department of Osteology and Biomechanics University Medical Center Hamburg-Eppendorf Hamburg Germany.,Department of Orthopedics University Medical Center Hamburg-Eppendorf Hamburg Germany
| | - Ralf Oheim
- Department of Osteology and Biomechanics University Medical Center Hamburg-Eppendorf Hamburg Germany
| | - Michael Amling
- Department of Osteology and Biomechanics University Medical Center Hamburg-Eppendorf Hamburg Germany
| | - Florian Barvencik
- Department of Osteology and Biomechanics University Medical Center Hamburg-Eppendorf Hamburg Germany
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82
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Rassie K, Dray M, Michigami T, Cundy T. Bisphosphonate Use and Fractures in Adults with Hypophosphatasia. JBMR Plus 2019; 3:e10223. [PMID: 31687651 PMCID: PMC6820463 DOI: 10.1002/jbm4.10223] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 06/24/2019] [Accepted: 07/15/2019] [Indexed: 02/06/2023] Open
Abstract
Adults with hypophosphatasia (HPP) may suffer femoral fractures resembling the atypical femoral fractures that can occur with long‐term bisphosphonate treatment, and there is an emerging consensus that bisphosphonates should not be used in adults with HPP and low bone mass. However, the spectrum of HPP in adults is wide: ranging from the severely affected—who commonly have osteomalacia—through to the minimally affected. The former typically have biallelic and the latter, heterozygous ALPL mutations. We have reviewed reports of fractures in adults with genetically proven HPP which suggest that the risk of fracture is at least 200‐fold greater in those with biallelic mutations. We also discuss two cases of postmenopausal women with heterozygous ALPL mutations. One had fractures and severe osteoporosis, but histology revealed no evidence of osteomalacia. The second had taken alendronate for 8 years, but despite profound suppression of bone turnover, histology again revealed no evidence of osteomalacia. The management of adults with HPP who have coexisting osteoporosis is challenging. More data are clearly needed, but we suggest that the risks of bisphosphonate therapy may be relatively low in patients who have heterozygous mutations and no histological evidence of osteomalacia. © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research © 2019 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Kate Rassie
- Department of Endocrinology Greenlane Clinical Centre Auckland New Zealand
| | - Michael Dray
- Department of Pathology Waikato Hospital Hamilton New Zealand
| | - Toshimi Michigami
- Department of Bone & Mineral Research Osaka Women's & Children's Hospital Isumi Japan
| | - Tim Cundy
- Department of Endocrinology Greenlane Clinical Centre Auckland New Zealand.,Department of Medicine, Faculty of Medical & Health Sciences University of Auckland Auckland New Zealand
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83
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Rush ET, Moseley S, Petryk A. Burden of disease in pediatric patients with hypophosphatasia: results from the HPP Impact Patient Survey and the HPP Outcomes Study Telephone interview. Orphanet J Rare Dis 2019; 14:201. [PMID: 31419999 PMCID: PMC6698035 DOI: 10.1186/s13023-019-1167-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 07/26/2019] [Indexed: 11/10/2022] Open
Abstract
Background Hypophosphatasia (HPP) is a rare, inherited, metabolic bone disease caused by deficient tissue-non-specific isoenzyme of alkaline phosphatase activity that manifests as a broad range of signs/symptoms, including bone mineralization defects and systemic complications. The burden of disease is poorly characterized, particularly in children. This study aimed to characterize the patient-reported burden of disease among children with HPP using two survey instruments: the HPP Impact Patient Survey (HIPS) and the HPP Outcomes Study Telephone interview (HOST). Methods Between September 2009 and June 2011, pediatric patients (aged younger than 18 years) with HPP were recruited to participate in the study via patient advocacy groups or their medical provider. Survey questions were used to capture information on patient demographics, HPP-related medical history, mobility, and health-related quality of life (HRQoL; using the 10-item Short-Form Health Survey for Children [SF-10], HIPS only). Results Common clinical features of the 59 pediatric survey respondents (mean [standard deviation] age: 7.6 [5.1] years; 51% male) included pain (86% of patients), muscle weakness (71%), difficulty gaining weight (64%), and delayed walking (59%). Fracture was reported by 36% of patients; multiple fractures were also reported (15% of patients). Use of assistive devices for mobility was frequent among the study population (51%). In response to the SF-10, patients reported a substantial impact of HPP on their HRQoL; physical function was the most severely impaired component relative to normative data. Of patients responding to the HOST, two-thirds experienced worsening of at least one of their HPP-related signs/symptoms over a 5-year period. Conclusions In pediatric patients, HPP is associated with a high burden of disease and a substantial negative impact on HRQoL. The burden of HPP may increase and HRQoL reduce further over time as signs/symptoms that affect HRQoL worsen or new signs/symptoms manifest. Electronic supplementary material The online version of this article (10.1186/s13023-019-1167-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Eric T Rush
- Children's Mercy Hospital, University of Missouri - Kansas City School of Medicine, Kansas City, MO, USA.
| | | | - Anna Petryk
- Alexion Pharmaceuticals, Inc., New Haven, CT, USA
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84
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Malabu UH, Lockett J, Lyster E, Maguire J, Tan Y. Atypical Tibial Fracture in a 63-Year-Old Woman With Intermittent Use of Bisphosphonate Unmasking Hypophosphatasia. J Endocr Soc 2019; 3:2082-2087. [PMID: 31663063 PMCID: PMC6812732 DOI: 10.1210/js.2019-00265] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 08/07/2019] [Indexed: 12/12/2022] Open
Abstract
We report an unusual case of atypical proximal tibial stress fracture (APTF) associated with intermittent use of bisphosphonates (BPs) and persistently low serum alkaline phosphatase (ALP) levels. We describe the case of a 63-year-old white woman who had experienced an APTF after 4 years of intermittent exposure to alendronate given for recurrent metatarsal stress fractures. BP administration was stopped after the diagnosis of the APTF. A review of her previous serum ALP levels revealed they had been consistently low. Adult hypophosphatasia (HPP) was diagnosed by the low serum ALP activity and elevated urine phosphoethanolamine levels. She was treated conservatively with analgesics. Adult HPP is an underrecognized condition associated with atypical insufficiency fractures, and BP use compounds this risk. To the best of our knowledge, we report the first case of intermittent BP exposure preceding an APTF in an adult patient with HPP, highlighting the uncommon site of the proximal tibia for BP-associated atypical insufficiency fractures, the need to screen for HPP in those with persistently low ALP levels before they begin BP therapy, and the importance of avoiding BP use in those with HPP.
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Affiliation(s)
- Usman H Malabu
- Department of Endocrinology and Diabetes, Townsville Hospital, Douglas, Queensland, Australia.,James Cook University College of Medicine and Dentistry, Townsville, Queensland, Australia.,Department of Endocrinology and Orthopedic Surgery, The Mater Hospital, Pimlico, Queensland, Australia
| | - Jack Lockett
- Department of Endocrinology and Diabetes, Townsville Hospital, Douglas, Queensland, Australia.,Faculty of Medicine, University of Queensland, Queensland, Australia
| | - Emma Lyster
- Townsville Family Medical Centre, Currajong, Queensland, Australia
| | - John Maguire
- Department of Endocrinology and Orthopedic Surgery, The Mater Hospital, Pimlico, Queensland, Australia
| | - YongMong Tan
- Department of Endocrinology and Diabetes, Townsville Hospital, Douglas, Queensland, Australia.,James Cook University College of Medicine and Dentistry, Townsville, Queensland, Australia.,Department of Endocrinology and Orthopedic Surgery, The Mater Hospital, Pimlico, Queensland, Australia
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85
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Martins L, de Almeida AB, Dos Santos EJL, Foster BL, Machado RA, Kantovitz KR, Coletta RD, Nociti FH. A novel combination of biallelic ALPL mutations associated with adult hypophosphatasia: A phenotype-genotype association and computational analysis study. Bone 2019; 125:128-139. [PMID: 31077853 DOI: 10.1016/j.bone.2019.05.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 04/28/2019] [Accepted: 05/07/2019] [Indexed: 02/07/2023]
Abstract
Hypophosphatasia (HPP) is an inherited metabolic disorder that causes defective skeletal and dental mineralization. HPP exhibits a markedly heterogeneous range of clinical manifestations caused by dysfunction of the tissue-nonspecific isozyme of alkaline phosphatase (TNSALP), resulting from loss-of-function mutations in the ALPL gene. HPP has been associated with predominantly missense mutations in ALPL, and a number of compound heterozygous genotypes have been identified. Here, we describe a case of a subject with adult-onset HPP caused by a novel combination of missense mutations p.Gly473Ser and p.Ala487Val, resulting in chronic musculoskeletal pain, myopathy, persistent fatigue, vomiting, and an uncommon dental phenotype of short-rooted permanent teeth. Pedigree and biochemical analysis indicated that severity of symptoms was correlated with levels of residual ALP activity, and co-segregated with the p.Gly473Ser missense mutation. Bioinformatic analysis to predict the structural and functional impact of each of the point mutations in the TNSALP molecule, and its potential contribution to the clinical symptoms, revealed that the affected Gly473 residue is localized in the homodimer interface and predicted to have a dominant negative effect. The affected Ala487 residue was predicted to bind to Tyr479, which is closely located the N-terminal α-helix of TNSALP monomer 2, suggesting that both changes may impair dimer stability and catalytic functions. In conclusion, these findings assist in defining genotype-phenotype associations for HPP, and further define specific sites within the TNSALP molecule potentially related to neuromuscular manifestations in adult HPP, allowing for a better understanding of HPP pathophysiology.
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Affiliation(s)
- Luciane Martins
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - Amanda Bandeira de Almeida
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - Elis Janaína Lira Dos Santos
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - Brian L Foster
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
| | - Renato Assis Machado
- Department of Oral Diagnosis, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - Kamila Rosamilia Kantovitz
- Department of Pediatric Dentistry, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil; Department of Dental Materials, São Leopoldo Mandic School of Dentistry and Research Center, Campinas, SP, Brazil
| | - Ricardo D Coletta
- Department of Oral Diagnosis, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil
| | - Francisco H Nociti
- Department of Prosthodontics and Periodontics, Division of Periodontics, Piracicaba Dental School, University of Campinas - UNICAMP, Piracicaba, SP, Brazil.
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86
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García-Fontana C, Villa-Suárez JM, Andújar-Vera F, González-Salvatierra S, Martínez-Navajas G, Real PJ, Gómez Vida JM, de Haro T, García-Fontana B, Muñoz-Torres M. Epidemiological, Clinical and Genetic Study of Hypophosphatasia in A Spanish Population: Identification of Two Novel Mutations in The Alpl Gene. Sci Rep 2019; 9:9569. [PMID: 31267001 PMCID: PMC6606844 DOI: 10.1038/s41598-019-46004-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 06/18/2019] [Indexed: 12/13/2022] Open
Abstract
Hypophosphatasia (HPP) is a genetic disease caused by one or several mutations in ALPL gene encoding the tissue-nonspecific alkaline phosphatase affecting the mineralization process. Due to its low prevalence and lack of recognition, this metabolic disorder is generally confused with other more frequent bone disorders. An assessment of serum total alkaline phosphatase (ALP) levels was performed in 78,590 subjects. Pyridoxal-5′-phosphate (PLP) concentrations were determined and ALPL gene was sequenced in patients potentially affected by HPP. Functional validation of the novel mutations found was performed using a cell-based assay. Our results showed persistently low serum ALP levels in 0.12% of subjects. Among the studied subjects, 40% presented with HPP-related symptoms. Nine of them (~28%) had a history of fractures, 5 (~16%) subjects showed chondrocalcinosis and 4 (~13%) subjects presented with dental abnormalities. Eleven subjects showed increased PLP concentrations. Seven of them showed ALPL gene mutations (2 of the mutations corresponded to novel genetic variants). In summary, we identified two novel ALPL gene mutations associated with adult HPP. Using this protocol, almost half of the studied patients were diagnosed with HPP. Based on these results, the estimated prevalence of mild HPP in Spain could be up to double than previously reported.
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Affiliation(s)
- Cristina García-Fontana
- University Hospital San Cecilio, Instituto de Investigación Biosanitaria (Ibs.GRANADA), Granada, Spain.,Fundación para la Investigación Biosanitaria de Andalucía Oriental (FIBAO), Granada, Spain
| | - Juan M Villa-Suárez
- Clinical Analysis Unit, University Hospital San Cecilio, Granada, Spain.,Department of Medicine, University of Granada, Granada, Spain
| | - Francisco Andújar-Vera
- University Hospital San Cecilio, Instituto de Investigación Biosanitaria (Ibs.GRANADA), Granada, Spain.,Fundación para la Investigación Biosanitaria de Andalucía Oriental (FIBAO), Granada, Spain
| | - Sheila González-Salvatierra
- University Hospital San Cecilio, Instituto de Investigación Biosanitaria (Ibs.GRANADA), Granada, Spain.,Fundación para la Investigación Biosanitaria de Andalucía Oriental (FIBAO), Granada, Spain.,Department of Medicine, University of Granada, Granada, Spain
| | - Gonzalo Martínez-Navajas
- Gene Regulation, Stem Cells & Development Lab, GENYO, Centre for Genomics and Oncological Research: Pfizer-University of Granada-Andalusian Regional Government, Granada, Spain.,Department of Biochemistry and Molecular Biology I, University of Granada, Granada, Spain
| | - Pedro J Real
- Gene Regulation, Stem Cells & Development Lab, GENYO, Centre for Genomics and Oncological Research: Pfizer-University of Granada-Andalusian Regional Government, Granada, Spain.,Department of Biochemistry and Molecular Biology I, University of Granada, Granada, Spain
| | | | - Tomás de Haro
- Clinical Analysis Unit, University Hospital San Cecilio, Granada, Spain
| | - Beatriz García-Fontana
- University Hospital San Cecilio, Instituto de Investigación Biosanitaria (Ibs.GRANADA), Granada, Spain. .,CIBERFES, Instituto de Salud Carlos III, Granada, Spain.
| | - Manuel Muñoz-Torres
- University Hospital San Cecilio, Instituto de Investigación Biosanitaria (Ibs.GRANADA), Granada, Spain.,Department of Medicine, University of Granada, Granada, Spain.,CIBERFES, Instituto de Salud Carlos III, Granada, Spain.,Endocrinology and Nutrition Unit, University Hospital San Cecilio, Granada, Spain
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87
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Szabo SM, Tomazos IC, Petryk A, Powell LC, Donato BMK, Zarate YA, Tiulpakov A, Martos-Moreno GÁ. Frequency and age at occurrence of clinical manifestations of disease in patients with hypophosphatasia: a systematic literature review. Orphanet J Rare Dis 2019; 14:85. [PMID: 31023354 PMCID: PMC6485115 DOI: 10.1186/s13023-019-1062-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 04/08/2019] [Indexed: 11/26/2022] Open
Abstract
Background Hypophosphatasia (HPP) is a rare, inherited, metabolic disease caused by tissue-nonspecific alkaline phosphatase deficiency, characterized by bone mineralization defects and systemic complications. Understanding of the clinical course and burden of HPP is limited by its rarity. This systematic literature review and synthesis of case report data aimed to determine the frequency and timing of clinical HPP manifestations and events. Methods Case reports and series of patients with HPP who had been followed longitudinally for ≥1 year were identified. Demographics and clinical data of interest, identified through consultation with clinical experts in HPP, were extracted. Occurrences of clinical manifestations/events of interest were categorized, classified by age at first reported occurrence of HPP manifestations and visualized over time. Clinical manifestations/events considered to contribute to the clinical burden of HPP were identified. Kaplan–Meier curves were used to estimate the median (range) age at first occurrence of the most frequently reported manifestations/events. Results From the 283 studies that met the inclusion criteria, 265 patients with HPP with ≥1 year of longitudinal follow-up were identified (median [interquartile range] age 4 [0–34] years; 45% male). The types of clinical manifestations/events of interest experienced by individuals with ≥1 such manifestation/event (n = 261) often differed between older and younger patients. Most (94%) of the 265 patients experienced ≥1 manifestation/event deemed to contribute to the clinical burden of HPP; premature tooth loss (53.5%), fractures (35.8%), pain (33.6%), and gross motor/ambulation difficulties (30.9%) were most frequently reported. The median (range) age at first reported occurrence of respiratory symptoms, cranial abnormalities, and premature tooth loss ranged from 0.3 to 10 years, whereas the median age at first reported occurrence of fractures, pain, gross motor/ambulation difficulties, and surgery ranged from 33 to 70 years. Conclusions HPP is associated with a high clinical burden of disease, regardless of age at first reported occurrence of HPP manifestations. Over an individual’s lifetime, the types of manifestations/events experienced can change and multiple HPP-related clinical manifestations/events can accumulate. These observations may reflect evolution and progression of the disease. Electronic supplementary material The online version of this article (10.1186/s13023-019-1062-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | - Anna Petryk
- Alexion Pharmaceuticals, Inc., Boston, MA, USA.,Department of Pediatrics, Division of Pediatric Endocrinology, University of Minnesota, Minneapolis, MN, USA
| | | | | | - Yuri A Zarate
- Section of Genetics and Metabolism, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | | | - Gabriel Ángel Martos-Moreno
- Department of Endocrinology, Hospital Infantil Universitario Niño Jesús, IIS La Princesa, Madrid, Spain. .,Department of Pediatrics, Universidad Autónoma de Madrid, Madrid, Spain. .,CIBERobn, ISCIII, Madrid, Spain.
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Fukushima K, Kawai-Kowase K, Yonemoto Y, Fujiwara M, Sato H, Sato M, Kubota T, Ozono K, Tamura J. Adult hypophosphatasia with compound heterozygous p.Phe327Leu missense and c.1559delT frameshift mutations in tissue-nonspecific alkaline phosphatase gene: a case report. J Med Case Rep 2019; 13:101. [PMID: 31014398 PMCID: PMC6480864 DOI: 10.1186/s13256-019-2045-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2018] [Accepted: 03/08/2019] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Hypophosphatasia is an inherited bone disease characterized by low alkaline phosphatase activity encoded by ALPL. Clinically, hypophosphatasia can be categorized as perinatal, infantile, childhood, and adult forms, as well as odonto-hypophosphatasia, according to the age at first sign or dental manifestations. Adult hypophosphatasia typically presents in middle-aged patients who appear to be in good health in early adulthood and manifests as painful feet caused by recurrent, slow-healing stress fractures of the lower limb. Because the symptoms of adult hypophosphatasia vary and are common, many patients with hypophosphatasia might be not diagnosed accurately and thus may receive inappropriate treatment. CASE PRESENTATION We report a case of a 35-year-old Japanese woman with low serum alkaline phosphatase detected at a routine medical checkup. She had mild muscle/bone pain but no history of rickets, fractures, or dental problems. Measurement of bone mineral density of the lumbar spine and the femoral neck revealed osteopenia below the expected range for age in a young adult. Abdominal ultrasonography revealed numerous microcalcifications in both kidneys. Analysis of amino acids in urine revealed that phosphoethanolamine was elevated. Low serum alkaline phosphatase activity, elevation of phosphoethanolamine, and low bone mineral density supported the diagnosis of hypophosphatasia. ALPL mutation analysis revealed two mutations: p.Phe327Leu and c.1559delT. These genetic abnormalities were previously reported in perinatal, infantile, and childhood but not adult hypophosphatasia. On the basis of the clinical presentation, laboratory and imaging findings, and genetic analyses, the patient was definitively diagnosed with adult hypophosphatasia. To the best of our knowledge, this is the first case report of adult hypophosphatasia with the compound heterozygous mutations p.Phe327Leu and c.1559delT. CONCLUSIONS Although the risk of bone fracture was high in this case, treatment approaches differ between osteoporosis and hypophosphatasia. Because adult hypophosphatasia diagnosis is often difficult because of their varied symptoms, hypophosphatasia should be considered in the differential diagnosis of low serum alkaline phosphatase. Early diagnosis is important so that appropriate treatment can be initiated.
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Affiliation(s)
- Kazunori Fukushima
- Department of Emergency Medicine, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
| | - Keiko Kawai-Kowase
- Department of General Medicine, Gunma University Graduate School of Medicine, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8511, Japan.
| | - Yukio Yonemoto
- Department of Orthopedic Surgery, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
| | - Makoto Fujiwara
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Hiroko Sato
- Department of General Medicine, Gunma University Graduate School of Medicine, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Mahito Sato
- Department of General Medicine, Gunma University Graduate School of Medicine, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8511, Japan
| | - Takuo Kubota
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Junich Tamura
- Department of General Medicine, Gunma University Graduate School of Medicine, 3-39-15 Showa-machi, Maebashi, Gunma, 371-8511, Japan
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Kishnani PS, Rockman-Greenberg C, Rauch F, Bhatti MT, Moseley S, Denker AE, Watsky E, Whyte MP. Five-year efficacy and safety of asfotase alfa therapy for adults and adolescents with hypophosphatasia. Bone 2019; 121:149-162. [PMID: 30576866 DOI: 10.1016/j.bone.2018.12.011] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 12/11/2018] [Accepted: 12/13/2018] [Indexed: 12/12/2022]
Abstract
Hypophosphatasia (HPP) features low tissue-nonspecific alkaline phosphatase (TNSALP) isoenzyme activity resulting in extracellular accumulation of its substrates including pyridoxal 5'-phosphate (PLP), the principal circulating form of vitamin B6, and inorganic pyrophosphate (PPi), a potent inhibitor of mineralization. Asfotase alfa is an enzyme replacement therapy developed to treat HPP. This multinational, randomized, open-label study (NCT01163149; EudraCT 2010-019850-42) evaluated the efficacy and safety of asfotase alfa in adults and adolescents 13-66 years of age with HPP. The study comprised a 6-month primary treatment period and a 4.5-year extension phase. In the primary treatment period, 19 patients were randomized to receive asfotase alfa 0.3 mg/kg/d subcutaneously (SC; n = 7), asfotase alfa 0.5 mg/kg/d SC (n = 6), or no treatment (control; n = 6) for 6 months. In the extension phase, patients received asfotase alfa (0.5 mg/kg/d for 6 mo-1 y, then 1 mg/kg/d 6 d/wk). During the primary treatment period, changes from Baseline to Month 6 in plasma PLP and PPi concentrations (coprimary efficacy measure) were greater in the combined asfotase alfa group compared with the control group, reaching statistical significance for PLP (P = 0.0285) but not for PPi (P = 0.0715). However, for the total cohort, the within subject changes in both PLP and PPi after 6 months and over 5 years of treatment with asfotase alfa were significant (P < 0.05). Secondary efficacy measures included transiliac crest histomorphometry, dual-energy X-ray absorptiometry (DXA), and the 6-Minute Walk Test (6MWT). A significant decrease from Baseline in mineralization lag time was observed in the combined asfotase alfa group at Year 1. There were no significant differences between treated and control patients in DXA mean bone mineral density results at 6 months; Z-scores and T-scores were within the expected range for age at Baseline and remained so over 5 years of treatment. On the 6MWT, median (min, max) distance walked increased from 355 (10, 620; n = 19) meters before treatment to 450 (280, 707; n = 13) meters at 5 years (P < 0.05). Results for the exploratory outcome measures suggested improvements in gross motor function, muscle strength, and patient-reported functional disability over 5 years of treatment. There were no deaths during this study. Asfotase alfa was generally well tolerated; the most common adverse events were mild to moderate injection site reactions. This study suggests that in adults and adolescents with pediatric-onset HPP, treatment with asfotase alfa is associated with normalization of circulating TNSALP substrate levels and improved functional abilities.
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Affiliation(s)
| | - Cheryl Rockman-Greenberg
- The University of Manitoba, Rady Faculty of Health Sciences, Max Rady College of Medicine, Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada.
| | - Frank Rauch
- McGill University, Shriners Hospital for Children, Montreal, Quebec, Canada.
| | - M Tariq Bhatti
- Duke Eye Center, Duke University Medical Center, Durham, NC, USA
| | | | | | - Eric Watsky
- Alexion Pharmaceuticals, Inc., Boston, MA, USA.
| | - Michael P Whyte
- Center for Metabolic Bone Disease and Molecular Research, Shriners Hospital for Children, St. Louis, MO, USA; Division of Bone and Mineral Diseases, Department of Internal Medicine, Washington University School of Medicine at Barnes-Jewish Hospital, St. Louis, MO, USA.
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90
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Phillips D, Tomazos IC, Moseley S, L'Italien G, Gomes da Silva H, Lerma Lara S. Reliability and Validity of the 6-Minute Walk Test in Hypophosphatasia. JBMR Plus 2019; 3:e10131. [PMID: 31346563 PMCID: PMC6636775 DOI: 10.1002/jbm4.10131] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 11/09/2018] [Accepted: 11/21/2018] [Indexed: 12/16/2022] Open
Abstract
This investigation evaluated the reliability and validity of the 6‐Minute Walk Test (6MWT) in patients with pediatric hypophosphatasia (HPP). Children (aged 6 to 12 years; n = 11), adolescents (13 to 17 years; n = 4), and adults (18 to 65 years; n = 9) completed the 6MWT at screening and baseline in two clinical studies of asfotase alfa. Test‐retest reliability of the 6MWT, evaluated with Pearson's correlation coefficients (r) for screening versus baseline, was high for children (r = 0.95; p < 0.0001), adolescents (r = 0.81; p = 0.125), and adults (r = 0.94; p = 0.0001). The most conservative minimal clinically important differences, estimated using distribution‐based methods, were 31 m (children and adults) and 43 m (adolescents). In children, the 6MWT correlated significantly with scores on measures of skeletal disease, which included the Radiographic Global Impression of Change scale (r = 0.50; p < 0.0001) and the Rickets Severity Scale (r = −0.78; p < 0.0001), such that distance walked increased as the severity of skeletal disease decreased. Significant (p < 0.0001) correlations with the 6MWT distance walked were also observed for children with scores on parent‐reported measures of disability (r = −0.67), ability to function in activities of daily living (r = 0.71 to 0.77), and parent‐reported measures of pain (r = −0.39). In adolescents and adults, 6MWT distance walked correlated significantly (p < 0.05) with measures of lower extremity function (r = 0.83 and 0.60, respectively), total pain severity (r = −0.41 and −0.36, respectively), and total pain interference (r = −0.41 and −0.49, respectively). Collectively, these data indicate that the 6MWT is a reliable, valid measure of physical functioning in patients with pediatric HPP. © 2018 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.
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Affiliation(s)
- Dawn Phillips
- Division of Physical Therapy Department of Allied Health Sciences University of North Carolina Chapel Hill NC USA
| | | | | | | | | | - Sergio Lerma Lara
- Centro Superior de Estudios Universitarios (CSEU) La Salle Universidad Autónoma de Madrid Madrid Spain.,Hospital Infantil Universitario Niño Jesús Madrid Spain
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Högler W, Langman C, Gomes da Silva H, Fang S, Linglart A, Ozono K, Petryk A, Rockman-Greenberg C, Seefried L, Kishnani PS. Diagnostic delay is common among patients with hypophosphatasia: initial findings from a longitudinal, prospective, global registry. BMC Musculoskelet Disord 2019; 20:80. [PMID: 30764793 PMCID: PMC6376686 DOI: 10.1186/s12891-019-2420-8] [Citation(s) in RCA: 59] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 01/16/2019] [Indexed: 12/04/2022] Open
Abstract
Background Hypophosphatasia (HPP) is a rare, systemic disease caused by mutation(s) within the ALPL gene encoding tissue-nonspecific alkaline phosphatase (ALP). HPP has a heterogeneous presentation, which coupled with its rarity, often leads to missed/delayed diagnosis and an incomplete understanding of its natural history. To better understand the epidemiology and clinical course of HPP, including timing of diagnosis after first reported manifestation, we present baseline data for patients enrolled in the Global HPP Registry. Methods Data were analyzed from patients with an HPP diagnosis confirmed by low serum ALP activity and/or an ALPL pathogenic variant, regardless of prior or current treatment, according to age at enrollment (children: < 18 y; adult: ≥18 y). All analyses were descriptive. Results Of 269 patients from 11 countries enrolled January 2015–September 2017, 121 (45.0%) were children and 148 (55.0%) were adults. The majority of children and adults were female (61.2 and 73.0%, respectively) and white (57.7 and 90.0%, respectively). Children had a median (min, max) age at earliest reported HPP manifestation of 7.2 months (− 2.3 mo, 16.0 y), which was > 12 months before diagnosis at age 20.4 months (− 0.2 mo, 16.0 y). In adults, the earliest reported manifestation occurred at a median (min, max) age of 37.6 years (0.2 y, 75.2 y), which preceded age at diagnosis (47.5 years [0.2 y, 75.2 y]) by ~ 10 years. Premature loss of deciduous teeth (48.2%, age ≥ 6 mo), bone deformity (32.5%), and failure to thrive (26.7%) were most commonly reported in the HPP-related disease history of children. Pain (74.5%), orthopedic procedures and therapies (44.6%), and recurrent and poorly healing fractures (36.5%) were most commonly reported in the HPP-related disease history of adults. Conclusions The Global HPP Registry represents the largest observational study of patients with HPP, capturing real world data. This analysis shows that diagnostic delay is common, reflecting limited awareness of HPP, and that HPP is associated with systemic manifestations across all ages. Many patients diagnosed in adulthood had HPP manifestations in childhood, highlighting the importance of taking thorough medical histories to ensure timely diagnosis. Trial registration Clinicaltrials.gov: NCT02306720, December 2014; ENCePP.eu: EUPAS13526, May 2016 (retrospectively registered).
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Affiliation(s)
- Wolfgang Högler
- Department of Pediatrics and Adolescent Medicine, Johannes Kepler University Linz, Linz, Austria
| | - Craig Langman
- Feinberg School of Medicine, Northwestern University and Lurie Children's Hospital, Chicago, IL, USA
| | | | - Shona Fang
- Alexion Pharmaceuticals, Inc., Boston, MA, USA
| | - Agnès Linglart
- APHP, Bicêtre Paris-Sud, University Paris Sud, Paris-Saclay, Le Kremlin Bicêtre, Paris, France
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University, Graduate School of Medicine, Suita, Osaka, Japan
| | - Anna Petryk
- Alexion Pharmaceuticals, Inc., Boston, MA, USA
| | - Cheryl Rockman-Greenberg
- Rady Faculty of Health Sciences, Max Rady College of Medicine, and Children's Hospital Research Institute of Manitoba, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Lothar Seefried
- Orthopaedic Clinic, König-Ludwig-Haus, University of Würzburg, Würzburg, Germany
| | - Priya S Kishnani
- Department of Pediatrics, Duke University Medical Center, 2301 Erwin Rd, Durham, NC, 27710, USA.
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92
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Galeano-Valle F, Vengoechea J, Galindo RJ. A rare mutation in hypophosphatasia: a case report of adult form and review of the literature. ARCHIVES OF ENDOCRINOLOGY AND METABOLISM 2019; 63:89-93. [PMID: 30864637 PMCID: PMC10118836 DOI: 10.20945/2359-3997000000108] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Accepted: 12/11/2018] [Indexed: 11/23/2022]
Abstract
Hypophosphatasia is a rare inborn error of metabolism characterized by low serum alkaline phosphatase activity due to loss-of-function mutations in the gene encoding the tissue-nonspecific isoenzyme of alkaline phosphatase (TNSALP). Extracellular accumulation of TNSALP substrates leads to dento-osseous and arthritic complications featuring tooth loss, rickets or osteomalacia, and calcific arthopathies. Mild hypophosphatasia usually has autosomal dominant inheritance, severe cases are either autosomal recessive or due to a dominant negative effect. Clinical manifestations of hypophosphatasia are extremely variable, ranging from life threatening to asymptomatic clinical presentations. The clinical presentation of the adult-onset hypophosphatasia is highly variable. Fractures, joint complications of chondrocalcinosis, calcifying polyarthritis and multiple pains may reveal minor forms of the disease in adults. It is important to recognize the disease to provide the best supportive treatment and to prevent the use of anti-resorption drugs in these patients. Bone-targeted enzyme-replacement therapy (asfotase alfa) was approved in 2015 to treat pediatric-onset hypophosphatasia. We present a case of a 41-year-old male diagnosed with adult form of hypophosphatasia with a rare ALPL mutation that has been previously described only once and review the literature on the adult form of the disease and its genetic mechanism.
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93
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A homozygous missense variant in the alkaline phosphatase gene ALPL is associated with a severe form of canine hypophosphatasia. Sci Rep 2019; 9:973. [PMID: 30700765 PMCID: PMC6353930 DOI: 10.1038/s41598-018-37801-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 12/13/2018] [Indexed: 12/25/2022] Open
Abstract
Inherited skeletal disorders affect both humans and animals. In the current study, we have performed series of clinical, pathological and genetic examinations to characterize a previously unreported skeletal disease in the Karelian Bear Dog (KBD) breed. The disease was recognized in seven KBD puppies with a variable presentation of skeletal hypomineralization, growth retardation, seizures and movement difficulties. Exome sequencing of one affected dog revealed a homozygous missense variant (c.1301T > G; p.V434G) in the tissue non-specific alkaline phosphatase gene, ALPL. The identified recessive variant showed full segregation with the disease in a cohort of 509 KBDs with a carrier frequency of 0.17 and was absent from 303 dogs from control breeds. In humans, recessive and dominant ALPL mutations cause hypophosphatasia (HPP), a metabolic bone disease with highly heterogeneous clinical manifestations, ranging from lethal perinatal hypomineralization to a relatively mild dental disease. Our study reports the first naturally occurring HPP in animals, resembling the human infantile form. The canine HPP model may serve as a preclinical model while a genetic test will assist in breeding programs.
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94
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Bowden SA, Foster BL. Alkaline Phosphatase Replacement Therapy for Hypophosphatasia in Development and Practice. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1148:279-322. [PMID: 31482504 DOI: 10.1007/978-981-13-7709-9_13] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Hypophosphatasia (HPP) is an inherited disorder that affects bone and tooth mineralization characterized by low serum alkaline phosphatase. HPP is caused by loss-of-function mutations in the ALPL gene encoding the protein, tissue-nonspecific alkaline phosphatase (TNSALP). TNSALP is expressed by mineralizing cells of the skeleton and dentition and is associated with the mineralization process. Generalized reduction of activity of the TNSALP leads to accumulation of its substrates, including inorganic pyrophosphate (PPi) that inhibits physiological mineralization. This leads to defective skeletal mineralization, with manifestations including rickets, osteomalacia, fractures, and bone pain, all of which can result in multi-systemic complications with significant morbidity, as well as mortality in severe cases. Dental manifestations are nearly universal among affected individuals and feature most prominently premature loss of deciduous teeth. Management of HPP has been limited to supportive care until the introduction of a TNSALP enzyme replacement therapy (ERT), asfotase alfa (AA). AA ERT has proven to be transformative, improving survival in severely affected infants and increasing overall quality of life in children and adults with HPP. This chapter provides an overview of TNSALP expression and functions, summarizes HPP clinical types and pathologies, discusses early attempts at therapies for HPP, summarizes development of HPP mouse models, reviews design and validation of AA ERT, and provides up-to-date accounts of AA ERT efficacy in clinical trials and case reports, including therapeutic response, adverse effects, limitations, and potential future directions in therapy.
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Affiliation(s)
- S A Bowden
- Division of Endocrinology, Department of Pediatrics, Nationwide Children's Hospital/The Ohio State University College of Medicine, Columbus, OH, USA.
| | - B L Foster
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH, USA
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95
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Taillandier A, Domingues C, Dufour A, Debiais F, Guggenbuhl P, Roux C, Cormier C, Cortet B, Porquet-Bordes V, Coury F, Geneviève D, Chiesa J, Colin T, Fletcher E, Guichet A, Javier RM, Laroche M, Laurent M, Lausch E, LeHeup B, Lukas C, Schwabe G, van der Burgt I, Muti C, Simon-Bouy B, Mornet E. Genetic analysis of adults heterozygous for ALPL mutations. J Bone Miner Metab 2018; 36:723-733. [PMID: 29236161 DOI: 10.1007/s00774-017-0888-6] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 11/11/2017] [Indexed: 12/11/2022]
Abstract
Hypophosphatasia (HPP) is a rare inherited metabolic bone disease due to a deficiency of the tissue nonspecific alkaline phosphatase isoenzyme (TNSALP) encoded by the ALPL gene. Patients have consistently low serum alkaline phosphatase (AP), so that this parameter is a good hallmark of the disease. Adult HPP is heterogeneous, and some patients present only mild nonpathognomonic symptoms which are also common in the general population such as joint pain, osteomalacia and osteopenia, chondrocalcinosis, arthropathy and musculoskeletal pain. Adult HPP may be recessively or dominantly inherited; the latter case is assumed to be due to the dominant negative effect (DNE) of missense mutations derived from the functional homodimeric structure of TNSALP. However, there is no biological argument excluding the possibility of other causes of dominant HPP. Rheumatologists and endocrinologists are increasingly solicited for patients with low AP and nonpathognomonic symptoms of HPP. Many of these patients are heterozygous for an ALPL mutation and a challenging question is to determine if these symptoms, which are also common in the general population, are attributable to their heterozygous ALPL mutation or not. In an attempt to address this question, we reviewed a cohort of 61 adult patients heterozygous for an ALPL mutation. Mutations were distinguished according to their statistical likelihood to show a DNE. One-half of the patients carried mutations predicted with no DNE and were slightly less severely affected by the age of onset, serum AP activity and history of fractures. We hypothesized that these mutations result in another mechanism of dominance or are recessive alleles. To identify other genetic factors that could trigger the disease phenotype in heterozygotes for potential recessive mutations, we examined the next-generation sequencing results of 32 of these patients for a panel of 12 genes involved in the differential diagnosis of HPP or candidate modifier genes of HPP. The heterozygous genotype G/C of the COL1A2 coding SNP rs42524 c.1645C > G (p.Pro549Ala) was associated with the severity of the phenotype in patients carrying mutations with a DNE whereas the homozygous genotype G/G was over-represented in patients carrying mutations without a DNE, suggesting a possible role of this variant in the disease phenotype. These preliminary results support COL1A2 as a modifier gene of HPP and suggest that a significant proportion of adult heterozygotes for ALPL mutations may have unspecific symptoms not attributable to their heterozygosity.
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Affiliation(s)
- Agnès Taillandier
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Christelle Domingues
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Annika Dufour
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Françoise Debiais
- Service de Rhumatologie, CHU de Poitiers, 86021, Poitiers cedex, France
| | - Pascal Guggenbuhl
- Service de Rhumatologie, hôpital Sud, CHU de Rennes, 16, boulevard de Bulgarie, BP90347, 35203, Rennes cedex 2, France
| | | | | | | | - Valérie Porquet-Bordes
- Endocrinologie, Maladies Osseuses, Génétique et Gynécologie Médicale, Hôpital des Enfants, CHU de Toulouse, Toulouse Cedex 9, France
| | - Fabienne Coury
- Service de Rhumatologie, CHU Lyon, Centre Hospitalier Lyon-Sud, Pierre Bénite, France
| | - David Geneviève
- Service de Génétique Clinique, Département de Génétique Médicale, maladies rares et médecine personnalisée, CHU Montpellier, université Montpellier, unité Inserm U1183, Montpellier, France
| | - Jean Chiesa
- Department of Genetics, University Hospital, Nîmes, France
| | - Thierry Colin
- Service de Rhumatologie, CH Public du Cotentin, Cherbourg, France
| | - Elaine Fletcher
- Clinical Genetics, Molecular Medicine Center, Western General Hospital, Edinburgh, UK
| | - Agnès Guichet
- Département Biochimie et génétique, CHU d'Angers, Angers, France
| | | | - Michel Laroche
- Service de Rhumatologie, Hôpital Pierre-Paul Riquet, Toulouse, France
| | - Michael Laurent
- Center for Metabolic Bone Diseases, University Hospitals Leuven, Leuven, Belgium
| | - Ekkehart Lausch
- Universitätsklinikum Freiburg, Zentrum für Kinder- und Jugendmedizin, Freiburg, Germany
| | - Bruno LeHeup
- Médecine infantile 3, CHU Nancy, Vandoeuvre, France
| | - Cédric Lukas
- Département de Rhumatologie, CHRU Montpellier, Montpellier, France
| | - Georg Schwabe
- Otto-Heubner-Centrum für Kinder und Jugendmedizin Allgemeine Päediatrie Charité, Campus Virchow Klinikum Augustenburger Platz 1, Berlin, Germany
| | | | - Christine Muti
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Brigitte Simon-Bouy
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France
| | - Etienne Mornet
- Unité de Génétique Constitutionnelle, Service de Biologie, Centre Hospitalier de Versailles, 177 rue de Versailles, 78150, Le Chesnay, France.
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Vinan-Vega MN, Abate EG. HYPOPHOSPHATASIA: CLINICAL ASSESSMENT AND MANAGEMENT IN THE ADULT PATIENT-A NARRATIVE REVIEW. Endocr Pract 2018; 24:1086-1092. [PMID: 30289311 DOI: 10.4158/ep-2018-0194] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To review literature and present a schematic approach to hypophosphatasia (HPP) evaluation and management applicable to practicing physicians to ease its recognition and diagnosis. METHODS Studies were obtained from online databases PubMed and MEDLINE using keyword 'hypophosphatasia.' RESULTS HPP is a rare disease characterized by low serum alkaline phosphatase along with diverse musculoskeletal symptoms that mimic different disorders. To date, the prevalence of HPP and its impact on adults has been unrecognized. There is lack of evidence from larger and long-term studies examining the adult type of this condition. CONCLUSION It is essential to increase awareness on the complexity of the pathophysiology and clinical features of HPP, which causes debilitating physical conditions that severely affects quality of life. A better comprehension of adult forms of HPP is essential to reduce a delay in diagnosis as well as ensure suitable management. ABBREVIATIONS ALP = alkaline phosphatase; HPP = hypophosphatasia; PEA = phosphorethanolamine; PLP = pyridoxal-5-phosphate; PPi = inorganic pyrophosphate; TNSALP/TNAP = tissue-nonspecific alkaline phosphatase.
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97
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Bowden SA, Foster BL. Profile of asfotase alfa in the treatment of hypophosphatasia: design, development, and place in therapy. Drug Des Devel Ther 2018; 12:3147-3161. [PMID: 30288020 PMCID: PMC6161731 DOI: 10.2147/dddt.s154922] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Hypophosphatasia (HPP) is a multi-systemic metabolic disorder caused by loss-of-function mutations in the ALPL gene that encodes the mineralization-associated enzyme, tissue-nonspecific alkaline phosphatase (TNSALP). HPP is characterized by defective bone and dental mineralization, leading to skeletal abnormalities with complications resulting in significant morbidity and mortality. Management of HPP has been limited to supportive care until the introduction of a recently approved enzyme replacement therapy employing bone-targeted recombinant human TNSALP, asfotase alfa (AA). This new therapy has been transformative as it improves survival in severely affected infants, and overall quality of life in children and adults with HPP. This review provides an overview of HPP, focusing on important steps in the development of AA enzyme replacement therapy, including the drug design, preclinical studies in the HPP mouse model, and outcomes from clinical trials and case report publications to date, with special attention given to response to therapy of skeletal manifestations, biochemical features, and other clinical manifestations. The limitations, adverse effects, and outcomes of AA are outlined and the place in therapy for individuals with HPP is discussed.
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Affiliation(s)
- Sasigarn A Bowden
- Division of Endocrinology, Department of Pediatrics, Nationwide Children's Hospital/The Ohio State University College of Medicine, Columbus, OH 43205, USA,
| | - Brian L Foster
- Division of Biosciences, College of Dentistry, The Ohio State University, Columbus, OH 43205, USA
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Shajani-Yi Z, Johnston AA, Casella SJ, Cervinski MA. Low serum alkaline phosphatase activity due to asymptomatic hypophosphatasia in a teenage girl. Clin Biochem 2018; 59:90-92. [DOI: 10.1016/j.clinbiochem.2018.06.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 06/25/2018] [Accepted: 06/25/2018] [Indexed: 11/28/2022]
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Daniel AB, Saraff V, Shaw NJ, Yates R, Mughal MZ, Padidela R. Healthcare resource utilization in the management of hypophosphatasia in three patients displaying a spectrum of manifestations. Orphanet J Rare Dis 2018; 13:142. [PMID: 30115096 PMCID: PMC6097329 DOI: 10.1186/s13023-018-0869-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 07/03/2018] [Indexed: 01/09/2023] Open
Abstract
Background Hypophosphatasia (HPP) is a rare, heterogeneous disease caused by low tissue-nonspecific alkaline phosphatase activity and associated with a range of signs and symptoms, including bone mineralization defects, respiratory problems, seizures, premature tooth loss, and fractures. Data from patients with HPP and their healthcare resource utilization are lacking. We evaluated healthcare utilization for 3 patients with differing severities of HPP. Results Patient 1 had perinatal HPP (received enzyme replacement therapy asfotase alfa under a compassionate use program), Patient 2 had infantile HPP, and Patient 3 had childhood HPP. Healthcare resources used in the National Health Service, England, were identified from coded activities in the hospital database and detailed medical records. These data showed that healthcare utilization was directly related to disease severity. Patient 1 had respiratory complications necessitating prolonged admission for ventilation from birth. Over 2.5 years, this patient was hospitalized 725 days, with visits from 16 specialists. Patient 2 had HPP-associated signs and symptoms starting in infancy, was treated for craniosynostosis, experienced multiple fractures, and required outpatient management for > 18 years. Patient 3 developed signs and symptoms of HPP in childhood and received outpatient and day case treatment for dental, orthopedic, and cardiovascular problems over 24 years. Healthcare utilization varied with severity and complexity of disease manifestations between these patients. Conclusions With the recent approval of asfotase alfa for HPP, data from this analysis may help mobilize multidisciplinary healthcare resources for management of HPP by elucidating healthcare resource needs of patients who show a spectrum of clinical manifestations of HPP.
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Affiliation(s)
- Anjali B Daniel
- Department of Paediatric Endocrinology & Metabolic Bone Diseases, Royal Manchester Children's Hospital, Oxford Road, Manchester, M13 9WL, UK
| | - Vrinda Saraff
- Department of Endocrinology and Diabetes, Birmingham Women's and Children's Hospital, Steelhouse Lane, Birmingham, B4 6NH, UK
| | - Nick J Shaw
- Department of Endocrinology and Diabetes, Birmingham Women's and Children's Hospital, Steelhouse Lane, Birmingham, B4 6NH, UK.,Institute of Metabolism and Systems Research, University of Birmingham, Edgbaston, Birmingham, B15 2TT, UK
| | - Robert Yates
- Department of Paediatric Intensive Care Unit, Royal Manchester Children's Hospital, Oxford Road, Manchester, M13 9WL, UK
| | - M Zulf Mughal
- Department of Paediatric Endocrinology & Metabolic Bone Diseases, Royal Manchester Children's Hospital, Oxford Road, Manchester, M13 9WL, UK.,Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Raja Padidela
- Department of Paediatric Endocrinology & Metabolic Bone Diseases, Royal Manchester Children's Hospital, Oxford Road, Manchester, M13 9WL, UK. .,Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, UK.
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100
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Peris P, González-Roca E, Rodríguez-García SC, Del Mar López-Cobo M, Monegal A, Guañabens N. Incidence of Mutations in the ALPL, GGPS1, and CYP1A1 Genes in Patients With Atypical Femoral Fractures. JBMR Plus 2018; 3:29-36. [PMID: 30680361 PMCID: PMC6339546 DOI: 10.1002/jbm4.10064] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Revised: 03/26/2018] [Accepted: 05/23/2018] [Indexed: 12/22/2022] Open
Abstract
Atypical femoral fractures (AFFs) are uncommon and often related to prolonged bisphosphonate (BP) treatment. Isolated cases have been linked to mutations of tissue nonspecific alkaline phosphatase (ALPL). Moreover, mutations in the geranylgeranyl pyrophosphate synthase (GGPPS) gene, which can be inhibited by BPs, and in the enzyme of the cytochrome P450 superfamily (CYP1A1), related to the metabolism of several drugs, have also been associated with AFF development. Our aim was to analyze the incidence of ALPL, GGPS1, and CYP1A1 gene mutations in patients with AFFs and their clinical characteristics. Seventeen women with AAFs were included. All patients underwent Sanger sequencing of the ALPL, GGPS1, and CYP1A1 genes, analyzing the presence of mutations and polymorphisms in these genes. The clinical characteristics of the patients, previous treatments, ALP substrates (vitamin B6 and phosphoethanolamine), bone turnover markers, and bone mass were also analyzed. Three of 17 patients (17.6%) presented heterozygous mutations in the ALPL (p.Gly288Ala) or CYP1A1 (p.Arg136His, p.Val409Ile) genes. Only the patient with the ALPL mutation presented increased ALP substrates. Patients with CYP1A1 variants had glucocorticoid-induced osteoporosis. All patients were previously treated with BPs during 85.5 ± 38 months, and nearly 50% were also treated with glucocorticoids. The AFF was bilateral in 35% of cases. In conclusion, ALPL and CYP1A1 mutations may be related to the development of AFF in patients treated with BPs. The evaluation of ALP substrates in patients with low ALPL levels allows the identification of patients with hypophosphatasia. The role of CYP1A1 mutations in AFF needs further study. © 2018 The Authors. JBMR Plus published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Pilar Peris
- Rheumatology Department Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) Network for Biomedical Research in Hepatic and Digestive Diseases (CIBERehd) Clínic Foundation for Biomedical Research (FCRB) Hospital Clínic University of Barcelona Barcelona Spain
| | - Eva González-Roca
- Immunology Department IDIBAPS CIBERehd FCRB Hospital Clínic University of Barcelona Barcelona Spain
| | - Sebastian C Rodríguez-García
- Rheumatology Department Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) Network for Biomedical Research in Hepatic and Digestive Diseases (CIBERehd) Clínic Foundation for Biomedical Research (FCRB) Hospital Clínic University of Barcelona Barcelona Spain
| | - María Del Mar López-Cobo
- Molecular Biology Core Laboratory IDIBAPS CIBERehd FCRB Hospital Clínic University of Barcelona Barcelona Spain
| | - Ana Monegal
- Rheumatology Department Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) Network for Biomedical Research in Hepatic and Digestive Diseases (CIBERehd) Clínic Foundation for Biomedical Research (FCRB) Hospital Clínic University of Barcelona Barcelona Spain
| | - Núria Guañabens
- Rheumatology Department Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS) Network for Biomedical Research in Hepatic and Digestive Diseases (CIBERehd) Clínic Foundation for Biomedical Research (FCRB) Hospital Clínic University of Barcelona Barcelona Spain
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