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Brener A, Cleper R, Baruch G, Rothschild E, Yackobovitch-Gavan M, Beer G, Zeitlin L, Kapusta L. Cardiovascular health in pediatric patients with X-linked hypophosphatemia under two years of burosumab therapy. Front Endocrinol (Lausanne) 2024; 15:1400273. [PMID: 38818505 PMCID: PMC11137213 DOI: 10.3389/fendo.2024.1400273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Accepted: 04/22/2024] [Indexed: 06/01/2024] Open
Abstract
Introduction X-linked hypophosphatemia (XLH) is caused by an inactivating mutation in the phosphate-regulating endopeptidase X-linked (PHEX) gene whose defective product fails to control phosphatonin fibroblast growth factor 23 (FGF23) serum levels. Although elevated FGF23 levels have been linked with detrimental cardiac effects, the cardiologic outcomes in XLH patients have been subject to debate. Our study aimed to evaluate the prevalence and severity of cardiovascular morbidity in pediatric XLH patients before, during, and after a 2-year treatment period with burosumab, a recombinant anti-FGF23 antibody. Methods This prospective observational study was conducted in a tertiary medical center, and included 13 individuals with XLH (age range 0.6-16.2 years) who received burosumab every 2 weeks. Clinical assessment at treatment initiation and after .5, 1, and 2 years of uninterrupted treatment included anthropometric measurements and cardiologic evaluations (blood pressure [BP], electrocardiogram, conventional echocardiography, and myocardial strain imaging). Results The linear growth of all patients improved significantly (mean height z-score: from -1.70 ± 0.80 to -0.96 ± 1.08, P=0.03). Other favorable effects were decline in overweight/obesity rates (from 46.2% to 23.1%) and decreased rates of elevated BP (systolic BP from 38.5% to 15.4%; diastolic BP from 38.5% to 23.1%). Electrocardiograms revealed no significant abnormality throughout the study period. Cardiac dimensions and myocardial strain parameters were within the normative range for age at baseline and remained unchanged during the study period. Conclusion Cardiologic evaluations provided reassurance that 2 years of burosumab therapy did not cause cardiac morbidity. The beneficial effect of this treatment was a reduction in cardiovascular risk factors, as evidenced by the lower prevalence of both overweight/obesity and elevated BP.
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Affiliation(s)
- Avivit Brener
- Institute of Pediatric Endocrinology and Diabetes, Dana-Dwek Children’s Hospital, Sourasky Medical Center, Tel Aviv, Israel
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Roxana Cleper
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- The Pediatric Nephrology Unit, Dana-Dwek Children’s Hospital, Sourasky Medical Center, Tel Aviv, Israel
| | - Guy Baruch
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Department of Internal Medicine, Sourasky Medical Center, Tel Aviv, Israel
| | - Ehud Rothschild
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- Department of Internal Medicine, Sourasky Medical Center, Tel Aviv, Israel
| | - Michal Yackobovitch-Gavan
- Department of Epidemiology and Preventive Medicine, School of Public Health, Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Gil Beer
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- The Pediatric Cardiology Unit, Dana-Dwek Children’s Hospital, Sourasky Medical Center, Tel Aviv, Israel
| | - Leonid Zeitlin
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- The Metabolic Bone Disease Unit, Pediatric Orthopedic Department, Dana-Dwek Children’s Hospital, Sourasky Medical Center, Tel Aviv, Israel
| | - Livia Kapusta
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
- The Pediatric Cardiology Unit, Dana-Dwek Children’s Hospital, Sourasky Medical Center, Tel Aviv, Israel
- Department of Pediatrics, Amalia Children’s Hospital, Radboud University Medical Centre, Nijmegen, Netherlands
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Bandyopadhyay S, Jain N, Bandyopadhyay A. Anaesthetic concerns of a child with symptomatic vitamin D deficiency rickets with secondary hyperparathyroidism: A case report. J Perioper Pract 2024:17504589241242229. [PMID: 38606917 DOI: 10.1177/17504589241242229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/13/2024]
Abstract
Rickets is a paediatric bone disorder characterised by defective mineralisation of bony matrix due to abnormalities in calcium and phosphate metabolism. Despite being a common disease globally, literature on the anaesthetic concerns in rickets are scant. Herein, we describe the management of a 12-year-old child with symptomatic vitamin D deficiency rickets with secondary hyperparathyroidism, undergoing general anaesthesia for an urgent orthopaedic procedure. There are numerous risks involved in such a case, such as hypocalcemia, hypophosphatemia, chest and vertebral deformities, restrictive lung disease, difficult intubation and weaning, difficult regional anaesthesia, chronic bone pain, infectious complications and postoperative decreased renal function, all of which require careful preoperative assessment and risk stratification. In elective surgeries, it is important to optimise the metabolic parameters before taking up the case. However, in urgent and emergent procedures like ours, it is imperative to take up the case after informing the parents of the risks involved.
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Affiliation(s)
- Soumily Bandyopadhyay
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, India
| | - Nisha Jain
- Department of Anaesthesiology, Pain Medicine and Critical Care, All India Institute of Medical Sciences, New Delhi, India
| | - Anjishnujit Bandyopadhyay
- Department of Anaesthesiology, Pain Medicine and Critical Care, Jai Prakash Narayan Apex Trauma Centre, All India Institute of Medical Sciences, New Delhi, India
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Bouzemane A, Vignot E, Derain Dubourg L, De Mul A, Molin A, Chapurlat R, Fontanges E, Delsart D, Akbari A, Huang SHS, McIntyre CW, Bacchetta J, Lemoine S. Reassuring Data on the Cardiovascular Risk in Adults With X-linked Hypophosphatemia Receiving Conventional Therapy. J Clin Endocrinol Metab 2024; 109:e488-e494. [PMID: 37843399 DOI: 10.1210/clinem/dgad608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 09/04/2023] [Accepted: 10/11/2023] [Indexed: 10/17/2023]
Abstract
CONTEXT X-linked hypophosphatemia (XLH) is a rare genetic disorder that results in increased plasma levels of fibroblast growth factor 23 (FGF23). Several studies have demonstrated a direct association between FGF23 and cardiovascular mortality in cohorts of patients with chronic renal failure. However, in patients with XLH, studies on the cardiovascular impact of the disease are rare, with contradictory results. OBJECTIVE The aim was to assess whether the disease led to an increased cardiovascular risk. METHODS We conducted a single-center retrospective observational study on a local cohort of adult patients with XLH. The primary endpoint was a composite endpoint of the frequency of left ventricular hypertrophy (LVH) or presence of high blood pressure. Our secondary objectives were to assess echocardiographic, pulse wave velocity, and central blood pressure data as other markers of CV health. Independently of this cohort, tissue sodium content with magnetic resonance imaging was studied in 2 patients with XLH before and after burosumab. RESULTS Twenty-two patients were included. Median serum phosphate was 0.57 (0.47-0.72) mmol/L and FGF23 94 pg/L (58-2226). Median blood pressure was 124 (115-130)/68 (65-80) mm Hg, with only 9% of patients being hypertensive. A majority of patients (69%) had no LVH, only 1 had a left ventricular mass >100 g/m² and 25% of patients had left ventricular remodeling. Pulse wave velocity was normal in all patients. No differences in skin and muscle sodium content were observed before and after burosumab in the 2 patients who underwent sodium magnetic resonance imaging. CONCLUSION We found no elevated risk of developing hypertension or LVH in patients with XLH.
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Affiliation(s)
- Alexandre Bouzemane
- Hospices Civils de Lyon, Nephrology, hypertension renal and functional exploration, Hôpital Edouard Herriot, 69003, Lyon, France
| | | | - Laurence Derain Dubourg
- Hospices Civils de Lyon, Nephrology, hypertension renal and functional exploration, Hôpital Edouard Herriot, 69003, Lyon, France
| | - Aurélie De Mul
- Reference centre for rare calcium and phosphorus diseases, paediatric rheumatology and dermatology, rare diseases network, OSCAR, ORKID, ERKNet BOND, HFME, Bron 69029, France
| | - Arnaud Molin
- Genetic department, Centre Hospitalier Universitaire de Caen, Caen, 14033, France
| | - Roland Chapurlat
- Rheumatology Department, CHU Edouard-Herriot, 69003 Lyon, France
| | | | - Daphne Delsart
- Cardiology functional explorations, Hopital Edouard-Herriot, 69003 Lyon, France
| | - Alireza Akbari
- Canada Kidney clinical research unit, London Health Sciences Centre, East London, ON, N6A 5W9Canada
| | - Shih Han Susan Huang
- Canada Kidney clinical research unit, London Health Sciences Centre, East London, ON, N6A 5W9Canada
| | - Christopher W McIntyre
- Canada Kidney clinical research unit, London Health Sciences Centre, East London, ON, N6A 5W9Canada
| | - Justine Bacchetta
- Reference centre for rare calcium and phosphorus diseases, paediatric rheumatology and dermatology, rare diseases network, OSCAR, ORKID, ERKNet BOND, HFME, Bron 69029, France
- University of Lyon, CarMeN Laboratory, IRIS Team, INSERM, INSERM1033, INRA, INSA Lyon, 69100, Villeurbanne, France
- INSERM 1033, prevention of bone diseases, 69008 Lyon, France
| | - Sandrine Lemoine
- Hospices Civils de Lyon, Nephrology, hypertension renal and functional exploration, Hôpital Edouard Herriot, 69003, Lyon, France
- Reference centre for rare calcium and phosphorus diseases, paediatric rheumatology and dermatology, rare diseases network, OSCAR, ORKID, ERKNet BOND, HFME, Bron 69029, France
- University of Lyon, CarMeN Laboratory, IRIS Team, INSERM, INSERM1033, INRA, INSA Lyon, 69100, Villeurbanne, France
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Bloudeau L, Linglart A, Flammier S, Portefaix A, Bertholet-Thomas A, Eddiry S, Barosi A, Salles JP, Porquet-Bordes V, Rothenbuhler A, Roger C, Bacchetta J. X-linked hypophosphatemia, obesity and arterial hypertension: data from the XLH21 study. Pediatr Nephrol 2023; 38:697-704. [PMID: 35758999 DOI: 10.1007/s00467-022-05636-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 05/09/2022] [Accepted: 05/13/2022] [Indexed: 01/19/2023]
Abstract
BACKGROUND The underlying mechanisms of obesity in X-linked hypophosphatemia (XLH) are not known. We aimed to evaluate whether FGF21, an endocrine FGF involved in the regulation of carbohydrate-lipid metabolism, could be involved. METHODS We performed a prospective multicenter cross-sectional study comparing FGF23, Klotho, and FGF21 levels in teenagers with XLH compared to healthy controls (VITADOS cohort) after matching for age, gender, and puberty. Non-parametric tests were performed (results presented as median (min-max)). RESULTS A total of 40 XLH teenagers (n = 20 Standard Of Care, SOC, n = 20 burosumab) were included. While patients receiving burosumab displayed increased BMI as compared to patients receiving SOC, systolic blood pressure expressed as percentile was progressively and significantly lower when comparing the three groups: 77 (4-99) in SOC, 47 (9-98) in burosumab, and 28 (1-94) in controls (p = 0.007). When compared to patients receiving SOC, patients receiving burosumab displayed significantly increased phosphate and 1,25(OH)2D levels. We found increased Klotho levels in patients receiving burosumab. No differences were found for either carbohydrate-lipid biomarkers or FGF21 between the three groups. A total of 21 XLH patients (53%) had insulin resistance (HOMA > 2.4, N = 10 SOC, N = 11 burosumab). CONCLUSION FGF21 does not explain obesity/overweight in XLH. Of note, this study was performed in France in 2018-2019, early after the approval authorizing burosumab only in case of severe XLH despite SOC. As such, the data on systolic blood pressure highlighting a possible impact of burosumab to decrease blood pressure as well as increase Klotho levels deserve further studies given their potential effect on long-term cardiovascular risk. A higher resolution version of the Graphical abstract is available as Supplementary information.
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Affiliation(s)
- Louisa Bloudeau
- Centre de Référence Des Maladies Rares du Calcium Et du Phosphate, Centre de Référence Des Maladies Rénales Rares, Filières Maladies Rares OSCAR, ORKID Et ERK-Net, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, 69500, France
| | - Agnès Linglart
- Centre de Référence Des Maladies Rares du Calcium Et du Phosphate, Filière de Santé Maladies Rares OSCAR, Endocrinologie Et Diabète de L'enfant, Hôpital Bicêtre Paris-Saclay, Université Paris Saclay, AP-HP, DMU SEA, INSERM U1185, Paris, 94270, France
| | - Sacha Flammier
- Centre de Référence Des Maladies Rares du Calcium Et du Phosphate, Centre de Référence Des Maladies Rénales Rares, Filières Maladies Rares OSCAR, ORKID Et ERK-Net, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, 69500, France
| | - Aurélie Portefaix
- Centre d'Investigation Clinique, EPICIME-CIC 1407, Hospices Civils de Lyon, Bron, 69500, France
| | - Aurélia Bertholet-Thomas
- Centre de Référence Des Maladies Rares du Calcium Et du Phosphate, Centre de Référence Des Maladies Rénales Rares, Filières Maladies Rares OSCAR, ORKID Et ERK-Net, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, 69500, France
| | - Sanaa Eddiry
- Centre de Référence Des Maladies Rares du Calcium Et du Phosphate, CHU de Toulouse, Toulouse, 31059, France
| | - Anna Barosi
- Centre de Référence Des Maladies Rares du Calcium Et du Phosphate, Filière de Santé Maladies Rares OSCAR, Endocrinologie Et Diabète de L'enfant, Hôpital Bicêtre Paris-Saclay, Université Paris Saclay, AP-HP, DMU SEA, INSERM U1185, Paris, 94270, France
| | - Jean-Pierre Salles
- Centre de Référence Des Maladies Rares du Calcium Et du Phosphate, CHU de Toulouse, Toulouse, 31059, France
| | - Valérie Porquet-Bordes
- Centre de Référence Des Maladies Rares du Calcium Et du Phosphate, CHU de Toulouse, Toulouse, 31059, France
| | - Anya Rothenbuhler
- Centre de Référence Des Maladies Rares du Calcium Et du Phosphate, Filière de Santé Maladies Rares OSCAR, Endocrinologie Et Diabète de L'enfant, Hôpital Bicêtre Paris-Saclay, Université Paris Saclay, AP-HP, DMU SEA, INSERM U1185, Paris, 94270, France
| | - Christelle Roger
- Service de Biochimie Et Biologie Moléculaire, Hôpital Lyon Sud, Pierre-Bénite, 69310, France.,Faculté de Médecine Lyon Est, INSERM, UMR 1033, Université Claude Bernard Lyon1, Lyon, 69008, France
| | - Justine Bacchetta
- Centre de Référence Des Maladies Rares du Calcium Et du Phosphate, Centre de Référence Des Maladies Rénales Rares, Filières Maladies Rares OSCAR, ORKID Et ERK-Net, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, 69500, France. .,Faculté de Médecine Lyon Est, INSERM, UMR 1033, Université Claude Bernard Lyon1, Lyon, 69008, France. .,Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, Lyon, 69008, France. .,Néphrologie, Rhumatologie Et Dermatologie Pédiatriques Hôpital Femme Mère Enfant, 59 boulevard Pinel, Bron Cedex, 69677, France.
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Méaux MN, Alioli C, Linglart A, Lemoine S, Vignot E, Bertholet-Thomas A, Peyruchaud O, Flammier S, Machuca-Gayet I, Bacchetta J. X-Linked Hypophosphatemia, Not Only a Skeletal Disease But Also a Chronic Inflammatory State. J Clin Endocrinol Metab 2022; 107:3275-3286. [PMID: 36112422 DOI: 10.1210/clinem/dgac543] [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: 05/08/2022] [Indexed: 02/13/2023]
Abstract
CONTEXT X-linked hypophosphatemia (XLH) is a rare genetic disease caused by a primary excess of fibroblast growth factor 23 (FGF23). FGF23 has been associated with inflammation and impaired osteoclastogenesis, but these pathways have not been investigated in XLH. OBJECTIVE This work aimed to evaluate whether XLH patients display peculiar inflammatory profile and increased osteoclastic activity. METHODS We performed a prospective, multicenter, cross-sectional study analyzing transcript expression of 8 inflammatory markers (Il6, Il8, Il1β, CXCL1, CCL2, CXCR3, Il1R, Il6R) by real-time quantitative polymerase chain reaction on peripheral blood mononuclear cells (PBMCs) purified from total blood samples extracted from patients and healthy control individuals. The effect of native/active vitamin D on osteoclast formation was also assessed in vitro from XLH patients' PBMCs. RESULTS In total, 28 XLH patients (17 children, among them 6 undergoing standard of care [SOC] and 11 burosumab therapy) and 19 controls were enrolled. Expression of most inflammatory markers was significantly increased in PBMCs from XLH patients compared to controls. No differences were observed between the burosumab and SOC subgroups. Osteoclast formation was significantly impaired in XLH patients. XLH mature osteoclasts displayed higher levels of inflammatory markers, being however lower in cells derived from the burosumab subgroup (as opposed to SOC). CONCLUSION We describe for the first time a peculiar inflammatory profile in XLH. Since XLH patients have a propensity to develop arterial hypertension, obesity, and enthesopathies, and because inflammation can worsen these clinical outcomes, we hypothesize that inflammation may play a critical role in these extraskeletal complications of XLH.
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Affiliation(s)
- Marie-Noëlle Méaux
- Service de Néphrologie, Rhumatologie et Dermatologie Pédiatriques, Centre de Référence des Maladies Rares du Calcium et du Phosphore, Centre de Référence des Maladies Rénales Rares Filières Maladies Rares ORKID, OSCAR et ERN ERK-Net, CHU de Lyon, 69 500 Bron, France
- INSERM, UMR 1033, Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 008 Lyon, France
| | - Candide Alioli
- INSERM, UMR 1033, Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 008 Lyon, France
| | - Agnès Linglart
- AP-HP, Université Paris Saclay, INSERM, Service d'endocrinologie et diabète de l'enfant, Centre de Référence des Maladies Rares du Calcium et du Phosphore, Filière de Santé Maladies Rares OSCAR, ERN endoRARE et BOND, Plateforme d'expertise des maladies rares Paris Saclay, Hôpital Bicêtre Paris-Saclay, 94 270 Le Kremlin-Bicêtre, France
| | - Sandrine Lemoine
- Département de Néphrologie, Service d'exploration Fonctionnelle rénale, Hôpital Edouard Herriot, 69 003 Lyon, France
- Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 003 Lyon, France
| | - Emmanuelle Vignot
- Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 003 Lyon, France
- Service de Rhumatologie, Hôpital Edouard Herriot, 69 003 Lyon, France
| | - Aurélia Bertholet-Thomas
- Service de Néphrologie, Rhumatologie et Dermatologie Pédiatriques, Centre de Référence des Maladies Rares du Calcium et du Phosphore, Centre de Référence des Maladies Rénales Rares Filières Maladies Rares ORKID, OSCAR et ERN ERK-Net, CHU de Lyon, 69 500 Bron, France
- INSERM, UMR 1033, Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 008 Lyon, France
| | - Olivier Peyruchaud
- INSERM, UMR 1033, Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 008 Lyon, France
| | - Sacha Flammier
- Service de Néphrologie, Rhumatologie et Dermatologie Pédiatriques, Centre de Référence des Maladies Rares du Calcium et du Phosphore, Centre de Référence des Maladies Rénales Rares Filières Maladies Rares ORKID, OSCAR et ERN ERK-Net, CHU de Lyon, 69 500 Bron, France
| | - Irma Machuca-Gayet
- INSERM, UMR 1033, Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 008 Lyon, France
| | - Justine Bacchetta
- Service de Néphrologie, Rhumatologie et Dermatologie Pédiatriques, Centre de Référence des Maladies Rares du Calcium et du Phosphore, Centre de Référence des Maladies Rénales Rares Filières Maladies Rares ORKID, OSCAR et ERN ERK-Net, CHU de Lyon, 69 500 Bron, France
- INSERM, UMR 1033, Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 008 Lyon, France
- Faculté de Médecine Lyon Est, Université Claude Bernard Lyon 1, 69 003 Lyon, France
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Treatment of X-Linked Hypophosphatemia in Children. ENDOCRINES 2022. [DOI: 10.3390/endocrines3030042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The conventional treatment for X-linked hypophosphatemia (XLH), consisting of phosphorus supplementation and a biologically active form of vitamin D (alfacalcidol or calcitriol), is used to treat rickets and leg deformities and promote growth. However, patients’ adult height often remains less than −2 SD. Moreover, adverse events, such as renal calcification and hyperparathyroidism, may occur. The main pathology in XLH is caused by excessive production of fibroblast growth factor 23 (FGF23). Several studies have demonstrated that treatment with burosumab, a blocking neutralizing antibody against FGF23, is better than conventional therapy for severe XLH and has no serious, short-term side effects. Thus, treatment with burosumab may be an option for severe XLH. The present article reviews the conventional and burosumab therapies. In addition to the fact that the long-term efficacy of antibody-based treatment has not been demonstrated, there are other, unresolved issues concerning the burosumab treatment of XLH.
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Collins MT, Marcucci G, Anders HJ, Beltrami G, Cauley JA, Ebeling PR, Kumar R, Linglart A, Sangiorgi L, Towler DA, Weston R, Whyte MP, Brandi ML, Clarke B, Thakker RV. Skeletal and extraskeletal disorders of biomineralization. Nat Rev Endocrinol 2022; 18:473-489. [PMID: 35578027 DOI: 10.1038/s41574-022-00682-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/13/2022] [Indexed: 12/15/2022]
Abstract
The physiological process of biomineralization is complex and deviation from it leads to a variety of diseases. Progress in the past 10 years has enhanced understanding of the genetic, molecular and cellular pathophysiology underlying these disorders; sometimes, this knowledge has both facilitated restoration of health and clarified the very nature of biomineralization as it occurs in humans. In this Review, we consider the principal regulators of mineralization and crystallization, and how dysregulation of these processes can lead to human disease. The knowledge acquired to date and gaps still to be filled are highlighted. The disorders of mineralization discussed comprise a broad spectrum of conditions that encompass bone disorders associated with alterations of mineral quantity and quality, as well as disorders of extraskeletal mineralization (hyperphosphataemic familial tumoural calcinosis). Included are disorders of alkaline phosphatase (hypophosphatasia) and phosphate homeostasis (X-linked hypophosphataemic rickets, fluorosis, rickets and osteomalacia). Furthermore, crystallopathies are covered as well as arterial and renal calcification. This Review discusses the current knowledge of biomineralization derived from basic and clinical research and points to future studies that will lead to new therapeutic approaches for biomineralization disorders.
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Affiliation(s)
- Michael T Collins
- Skeletal Disorders and Mineral Homeostasis Section, National Institute of Dental and Craniofacial Research, NIH, Bethesda, MD, USA.
| | - Gemma Marcucci
- Bone Metabolic Diseases Unit, Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Florence, Italy
| | - Hans-Joachim Anders
- Department of Medicine IV, Hospital of the University of Munich, Ludwig-Maximilians University, Munich, Germany
| | - Giovanni Beltrami
- Department Paediatric Orthopedic Oncology, Careggi and Meyer Children Hospital, Florence, Italy
| | - Jane A Cauley
- Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA
| | - Peter R Ebeling
- Department of Medicine, School of Clinical Sciences, Monash University, Melbourne, Australia
| | - Rajiv Kumar
- Departments of Medicine, Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN, USA
| | - Agnès Linglart
- APHP, Endocrinologie et diabète de l'enfant, Paris, France
| | - Luca Sangiorgi
- Medical Genetics and Skeletal Rare Diseases, IRCCS Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Dwight A Towler
- University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ria Weston
- Cardiovascular Research Group, Manchester Metropolitan University, Manchester, UK
| | - 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, St Louis, MO, USA
| | | | - Bart Clarke
- Mayo Clinic Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Rochester, MN, USA
| | - Rajesh V Thakker
- Academic Endocrine Unit, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
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Trombetti A, Al-Daghri N, Brandi ML, Cannata-Andía JB, Cavalier E, Chandran M, Chaussain C, Cipullo L, Cooper C, Haffner D, Harvengt P, Harvey NC, Javaid MK, Jiwa F, Kanis JA, Laslop A, Laurent MR, Linglart A, Marques A, Mindler GT, Minisola S, Yerro MCP, Rosa MM, Seefried L, Vlaskovska M, Zanchetta MB, Rizzoli R. Interdisciplinary management of FGF23-related phosphate wasting syndromes: a Consensus Statement on the evaluation, diagnosis and care of patients with X-linked hypophosphataemia. Nat Rev Endocrinol 2022; 18:366-384. [PMID: 35484227 DOI: 10.1038/s41574-022-00662-x] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/10/2022] [Indexed: 12/17/2022]
Abstract
X-linked hypophosphataemia (XLH) is the most frequent cause of hypophosphataemia-associated rickets of genetic origin and is associated with high levels of the phosphaturic hormone fibroblast growth factor 23 (FGF23). In addition to rickets and osteomalacia, patients with XLH have a heavy disease burden with enthesopathies, osteoarthritis, pseudofractures and dental complications, all of which contribute to reduced quality of life. This Consensus Statement presents the outcomes of a working group of the European Society for Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases, and provides robust clinical evidence on management in XLH, with an emphasis on patients' experiences and needs. During growth, conventional treatment with phosphate supplements and active vitamin D metabolites (such as calcitriol) improves growth, ameliorates leg deformities and dental manifestations, and reduces pain. The continuation of conventional treatment in symptom-free adults is still debated. A novel therapeutic approach is the monoclonal anti-FGF23 antibody burosumab. Although promising, further studies are required to clarify its long-term efficacy, particularly in adults. Given the diversity of symptoms and complications, an interdisciplinary approach to management is of paramount importance. The focus of treatment should be not only on the physical manifestations and challenges associated with XLH and other FGF23-mediated hypophosphataemia syndromes, but also on the major psychological and social impact of the disease.
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Affiliation(s)
- Andrea Trombetti
- Division of Bone Diseases, Department of Medicine, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland
- Division of Geriatrics, Department of Rehabilitation and Geriatrics, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland
| | - Nasser Al-Daghri
- Chair for Biomarkers of Chronic Diseases, Biochemistry Department, College of Science, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | | | - Jorge B Cannata-Andía
- Hospital Universitario Central de Asturias (HUCA), Oviedo, Spain
- Universidad de Oviedo, Oviedo, Spain
- Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
- Retic REDinREN-RICORS, 2040-ISCIII, Madrid, Spain
| | - Etienne Cavalier
- Department of Clinical Chemistry, University of Liege, CHU de Liège, Liège, Belgium
| | - Manju Chandran
- Complicated Metabolic Bone Disorders Clinic, Osteoporosis and Bone Metabolism Unit, Department of Endocrinology, Singapore General Hospital, Singapore, Singapore
| | - Catherine Chaussain
- Université de Paris, Institut des maladies musculo-squelettiques, URP2496, UFR Odontologie, Montrouge, France
- AP-HP, FHU DDS-Net, Centre de Référence des Maladies Rares du Métabolisme du Calcium et du Phosphore, Service médecine bucco-dentaire, Hôpital Bretonneau, GH Paris Nord Université de Paris, Paris, France
| | - Lucia Cipullo
- Patient representative with XLH, Geneva, Switzerland
| | - Cyrus Cooper
- MRC Lifecourse Epidemiology Centre, University of Southampton, Southampton, UK
- NIHR Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK
- NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
| | - Dieter Haffner
- Department of Paediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover, Germany
| | - Pol Harvengt
- XLH Belgium, Belgian association of patients with XLH (a member of the International XLH Alliance), Waterloo, Belgium
| | - Nicholas C Harvey
- MRC Lifecourse Epidemiology Centre, University of Southampton, Southampton, UK
- NIHR Southampton Biomedical Research Centre, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK
| | | | - Famida Jiwa
- Chair of the Committee of Patients Societies at the International Osteoporosis Foundation, Osteoporosis Canada, Toronto, Canada
| | - John A Kanis
- Mary McKillop Institute for Health Research, Australian Catholic University, Melbourne, Australia
- Centre for Metabolic Bone Diseases, University of Sheffield Medical School, Sheffield, UK
| | - Andrea Laslop
- Scientific Office, Federal Office for Safety in Health Care, Vienna, Austria
| | - Michaël R Laurent
- Centre for Metabolic Bone Diseases, University Hospitals Leuven, Leuven, Belgium
| | - Agnès Linglart
- Paris-Saclay University, INSERM U1185, Le Kremlin-Bicêtre, France
- AP-HP, endocrinology and diabetes for children, Reference centre for rare diseases of calcium and phosphate metabolism, OSCAR network, Platform of expertise for rare diseases of Paris Saclay Hospital, Bicêtre Paris Saclay Hospital, Le Kremlin-Bicêtre, France
| | - Andréa Marques
- Rheumatology Department, Centro Hospitalar Universitário de Coimbra, Coimbra, Portugal
- Health Sciences Research Unit: Nursing (UICiSA:E), Nursing School of Coimbra, Coimbra, Portugal
| | - Gabriel T Mindler
- Department of Paediatric Orthopaedics, Orthopaedic Hospital Speising, Vienna, Austria
- Vienna Bone and Growth Center, Vienna, Austria
| | - Salvatore Minisola
- Department of Clinical, Internal, Anaesthesiologic and Cardiovascular Sciences, 'Sapienza', Rome University, Rome, Italy
| | | | - Mario Miguel Rosa
- Departamento de Neurociências, Laboratório de Farmacologia Clínica E Terapêutica Faculdade de Medicina da Universidade de Lisboa, Lisbon, Portugal
| | - Lothar Seefried
- Orthopedic Department, University of Würzburg, Würzburg, Germany
| | - Mila Vlaskovska
- Medical Faculty, Department of Pharmacology, Medical University Sofia, Sofia, Bulgaria
| | - María Belén Zanchetta
- Instituto de Investigaciones Metabólicas (IDIM), Universidad del Salvador, Buenos Aires, Argentina
| | - René Rizzoli
- Division of Bone Diseases, Department of Medicine, Geneva University Hospitals and Faculty of Medicine, Geneva, Switzerland.
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9
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Baradhi K. Dramatic Transformation After Burosumab in a Young Boy With X-linked Hypophosphatemia: A Life-Changing Saga. Cureus 2022; 14:e22340. [PMID: 35371638 PMCID: PMC8938246 DOI: 10.7759/cureus.22340] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/16/2022] [Indexed: 12/04/2022] Open
Abstract
X-linked hypophosphatemia (XLH), also referred to as vitamin D-resistant rickets or X-linked dominant hypophosphatemic rickets, is a very rare metabolic disorder. Despite its rarity, it is the most common form of genetic rickets. XLH is caused by loss of function mutation in the phosphate-regulating endopeptidase homolog X-linked (PHEX) gene, resulting in excessive fibroblast growth factor 23 (FGF23) activity. The end result is renal phosphate wasting leading to hypophosphatemia. It is frequently misdiagnosed as nutritional rickets as it mimics clinical manifestations of vitamin D-deficient rickets; however, it remains refractory to vitamin D repletion. The clinical expression can be variable from progressive bowing to severe skeletal and dental abnormalities. Treatment was limited to calcitriol and phosphate supplementation until the emergence of burosumab, a humanized monoclonal antibody against FGF23. We here share our first-hand experience of the use of burosumab in a 14-year-old boy with XLH and how it dramatically improved his quality of life along with the review of the literature regarding XLH and burosumab.
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Affiliation(s)
- Krishna Baradhi
- Nephrology, University of Oklahoma School of Community Medicine, Tulsa, USA
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10
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Leifheit-Nestler M, Vogt I, Haffner D, Richter B. Phosphate Is a Cardiovascular Toxin. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2022; 1362:107-134. [DOI: 10.1007/978-3-030-91623-7_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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11
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Giannini S, Bianchi ML, Rendina D, Massoletti P, Lazzerini D, Brandi ML. Burden of disease and clinical targets in adult patients with X-linked hypophosphatemia. A comprehensive review. Osteoporos Int 2021; 32:1937-1949. [PMID: 34009447 PMCID: PMC8510985 DOI: 10.1007/s00198-021-05997-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 05/06/2021] [Indexed: 11/17/2022]
Abstract
UNLABELLED X-linked hypophosphataemia (XLH) is a lifelong condition. Despite the mounting clinical evidence highlighting the long-term multi-organ sequelae of chronic phosphate wasting and consequent hypophosphatemia over the lifetime and the morbidities associated with adult age, XLH is still perceived as a paediatric disease. INTRODUCTION Children who have XLH need to transition from paediatric to adult healthcare as young adults. While there is general agreement that all affected children should be treated (if the administration and tolerability of therapy can be adequately monitored), there is a lack of consensus regarding therapy in adults. METHODS To provide guidance in both diagnosis and treatment of adult XLH patients and promote better provision of care for this potentially underserved group of patients, we review the available clinical evidence and discuss the current challenges underlying the transition from childhood to adulthood care to develop appropriate management and follow-up patterns in adult XLH patients. RESULTS AND CONCLUSIONS Such a multi-systemic lifelong disease would demand that the multidisciplinary approach, successfully experienced in children, could be transitioned to adulthood care with an integration of specialized sub-disciplines to efficiently control musculoskeletal symptoms while optimizing patients' QoL. Overall, it would be desirable that transition to adulthood care could be a responsibility shared by the paediatric and adult XLH teams. Pharmacological management should require an adequate balance between the benefits derived from the treatment itself with complicated and long-term monitoring and the potential risks, as they may differ across age strata.
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Affiliation(s)
- S Giannini
- Department of Medicine, Clinica Medica 1, University of Padova, Padova, Italy.
| | - M L Bianchi
- Experimental Laboratory for Children's Bone Metabolism Research, Bone Metabolism Unit, Istituto Auxologico Italiano IRCCS, Milano, Italy
| | - D Rendina
- Department of Clinical Medicine and Surgery, Federico II University, Napoli, Italy
| | - P Massoletti
- Medical Affairs, Kyowa Kyrin, Basiglio, (MI), Italy
| | - D Lazzerini
- Medical Affairs, Kyowa Kyrin, Basiglio, (MI), Italy
| | - M L Brandi
- Metabolic Bone Diseases Unit, Department of Surgery and Translational Medicine, University of Firenze, Firenze, Italy
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12
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Constantacos C, Hunter JD, Walsh ET, South AM. Rare PHEX variant with insidious presentation leads to a delayed diagnosis of X-linked hypophosphatemia. BMJ Case Rep 2021; 14:14/5/e240336. [PMID: 34011663 DOI: 10.1136/bcr-2020-240336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
A 7-year-old girl without a significant previous medical history was diagnosed with X-linked hypophosphatemic rickets (XLHR) due to a rare, most likely pathogenic, PHEX gene variant after a 4-year delayed diagnosis due to mild clinical presentation. At 2 years of age, her intoeing and femoral bowing were attributed to physiologic bowing and borderline vitamin D sufficiency, despite phosphorus not being measured. Hypophosphatemia was eventually detected after incomplete improvement of bowing and leg length discrepancy with suboptimal linear growth. This rare PHEX variant (c.1949T>C, p.Leu650Pro) further supported the clinical diagnosis of XLHR. Treatment with burosumab (an anti-FGF23 monoclonal antibody) normalised phosphorus and alkaline phosphatase levels and improved her bowing. The diverse phenotypic presentation of this variant can result in delayed diagnosis and highlights the importance of prompt assessment of phosphorus levels in patients with skeletal deformities to ensure timely recognition and treatment.
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Affiliation(s)
- Cathrine Constantacos
- Pediatrics, Section of Endocrinology, Wake Forest University School of Medicine, Winston Salem, North Carolina, USA
| | - Janel Darcy Hunter
- Pediatrics, Section of Endocrinology, Wake Forest University School of Medicine, Winston Salem, North Carolina, USA
| | - Elizabeth Tharpe Walsh
- Pediatrics, Section of Endocrinology, Wake Forest University School of Medicine, Winston Salem, North Carolina, USA
| | - Andrew Michael South
- Pediatrics, Section of Nephrology, Wake Forest University School of Medicine, Winston Salem, North Carolina, USA.,Epidemiology and Prevention, Division of Public Health Sciences, Wake Forest University School of Medicine, Winston Salem, North Carolina, USA
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13
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Marcucci G, Brandi ML. Congenital Conditions of Hypophosphatemia Expressed in Adults. Calcif Tissue Int 2021; 108:91-103. [PMID: 32409880 DOI: 10.1007/s00223-020-00695-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 04/15/2020] [Indexed: 01/05/2023]
Abstract
The main congenital conditions of hypophosphatemia expressed in adulthood include several forms of hereditary hypophosphatemic rickets and a congenital disorder of vitamin D metabolism characterized by osteomalacia and hypophosphatemia in adult patients. Hypophosphatemia in adults is defined as serum phosphate concentration < 0.80 mmol/L. The principal regulators of phosphate homeostasis, as is well known, are parathyroid hormone (PTH), activated vitamin D, and Fibroblast Growth Factor 23 (FGF23). Differential diagnosis of hypophosphatemia is based on the evaluation of mechanisms leading to this alteration, such as high PTH activity, inadequate phosphate absorption from the gut, or renal phosphate wasting, either due to primary tubular defects or high FGF23 levels. The most common inherited form associated to hypophosphatemia is X-linked hypophosphatemic rickets (XLH), caused by PHEX gene mutations with enhanced secretion of the FGF23. Until now, the management of hypophosphatemia in adulthood has been poorly investigated. It is widely debated whether adult patients benefit from the conventional treatments normally used for pediatric patients. The new treatment for XLH with burosumab, a recombinant human IgG1 monoclonal antibody that binds to FGF23, blocking its activity, may change the pharmacological management of adult subjects with hypophosphatemia associated to FGF23-dependent mechanisms.
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Affiliation(s)
- Gemma Marcucci
- Bone Metabolic Diseases Unit, Department of Biomedical, Experimental and Clinical Sciences, University of Florence, AOU Careggi, Florence, Italy
| | - Maria Luisa Brandi
- Bone Metabolic Diseases Unit, Department of Biomedical, Experimental and Clinical Sciences, University of Florence, AOU Careggi, Florence, Italy.
- Head Bone Metabolic Diseases Unit, Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Largo Palagi 1, 50139, Florence, Italy.
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14
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Freundlich M, Gamba G, Rodriguez-Iturbe B. Fibroblast growth factor 23-Klotho and hypertension: experimental and clinical mechanisms. Pediatr Nephrol 2021; 36:3007-3022. [PMID: 33230698 PMCID: PMC7682775 DOI: 10.1007/s00467-020-04843-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 10/07/2020] [Accepted: 10/23/2020] [Indexed: 12/11/2022]
Abstract
Hypertension (HTN) and chronic kidney disease (CKD) are increasingly recognized in pediatric patients and represent risk factors for cardiovascular morbidity and mortality later in life. In CKD, enhanced tubular sodium reabsorption is a leading cause of HTN due to augmented extracellular fluid volume expansion. The renin-angiotensin-aldosterone system (RAAS) upregulates various tubular sodium cotransporters that are also targets of the hormone fibroblast growth factor 23 (FGF23) and its co-receptor Klotho. FGF23 inhibits the activation of 1,25-dihydroxyvitamin D that is a potent suppressor of renin biosynthesis. Here we review the complex interactions and disturbances of the FGF23-Klotho axis, vitamin D, and the RAAS relevant to blood pressure regulation and discuss the therapeutic strategies aimed at mitigating their pathophysiologic contributions to HTN.
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Affiliation(s)
- Michael Freundlich
- Department of Pediatrics, Division of Pediatric Nephrology, University of Miami Miller School of Medicine, Miami, FL, USA.
| | - Gerardo Gamba
- grid.9486.30000 0001 2159 0001Molecular Physiology Unit, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Mexico City, Mexico ,grid.416850.e0000 0001 0698 4037Department of Nephrology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
| | - Bernardo Rodriguez-Iturbe
- grid.416850.e0000 0001 0698 4037Department of Nephrology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico ,grid.419172.80000 0001 2292 8289Department of Nephrology, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City, Mexico
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15
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Laurent MR, De Schepper J, Trouet D, Godefroid N, Boros E, Heinrichs C, Bravenboer B, Velkeniers B, Lammens J, Harvengt P, Cavalier E, Kaux JF, Lombet J, De Waele K, Verroken C, van Hoeck K, Mortier GR, Levtchenko E, Vande Walle J. Consensus Recommendations for the Diagnosis and Management of X-Linked Hypophosphatemia in Belgium. Front Endocrinol (Lausanne) 2021; 12:641543. [PMID: 33815294 PMCID: PMC8018577 DOI: 10.3389/fendo.2021.641543] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 02/19/2021] [Indexed: 12/11/2022] Open
Abstract
X-linked hypophosphatemia (XLH) is the most common genetic form of hypophosphatemic rickets and osteomalacia. In this disease, mutations in the PHEX gene lead to elevated levels of the hormone fibroblast growth factor 23 (FGF23), resulting in renal phosphate wasting and impaired skeletal and dental mineralization. Recently, international guidelines for the diagnosis and treatment of this condition have been published. However, more specific recommendations are needed to provide guidance at the national level, considering resource availability and health economic aspects. A national multidisciplinary group of Belgian experts convened to discuss translation of international best available evidence into locally feasible consensus recommendations. Patients with XLH may present to a wide array of primary, secondary and tertiary care physicians, among whom awareness of the disease should be raised. XLH has a very broad differential-diagnosis for which clinical features, biochemical and genetic testing in centers of expertise are recommended. Optimal care requires a multidisciplinary approach, guided by an expert in metabolic bone diseases and involving (according to the individual patient's needs) pediatric and adult medical specialties and paramedical caregivers, including but not limited to general practitioners, dentists, radiologists and orthopedic surgeons. In children with severe or refractory symptoms, FGF23 inhibition using burosumab may provide superior outcomes compared to conventional medical therapy with phosphate supplements and active vitamin D analogues. Burosumab has also demonstrated promising results in adults on certain clinical outcomes such as pseudofractures. In summary, this work outlines recommendations for clinicians and policymakers, with a vision for improving the diagnostic and therapeutic landscape for XLH patients in Belgium.
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Affiliation(s)
- Michaël R. Laurent
- Centre for Metabolic Bone Diseases, University Hospitals Leuven, Leuven, Belgium
- *Correspondence: Michaël R. Laurent,
| | - Jean De Schepper
- Division of Pediatric Endocrinology, KidZ Health Castle, University Hospital Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
- Department of Pediatric Endocrinology, University Hospital Ghent, Ghent, Belgium
| | - Dominique Trouet
- Department of Pediatric Nephrology, Antwerp University Hospital, Antwerp, Belgium
- Laboratory of Experimental Medicine and Pediatrics, University of Antwerp, Antwerp, Belgium
| | - Nathalie Godefroid
- Pediatric Nephrology, Cliniques Universitaires St. Luc (UCL), Brussels, Belgium
| | - Emese Boros
- Paediatric Endocrinology Unit, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles, Brussels, Belgium
| | - Claudine Heinrichs
- Paediatric Endocrinology Unit, Hôpital Universitaire des Enfants Reine Fabiola, Université Libre de Bruxelles, Brussels, Belgium
| | - Bert Bravenboer
- Department of Endocrinology, University Hospital Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Brigitte Velkeniers
- Department of Endocrinology, University Hospital Brussels, Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Johan Lammens
- Department of Orthopaedic Surgery and Department of Development and Regeneration, Prometheus LRD Division of Skeletal Tissue Engineering, KU Leuven - University Hospitals Leuven, Leuven, Belgium
| | - Pol Harvengt
- XLH Belgium, Belgian X-Linked Hypophosphatemic Rickets (XLH) Patient Association, Waterloo, Belgium
| | - Etienne Cavalier
- Department of Clinical Chemistry, University Hospital Center of Liège, University of Liège, Liège, Belgium
| | - Jean-François Kaux
- Physical Medicine, Rehabilitation and Sports Traumatology, University and University Hospital of Liège, Liège, Belgium
| | - Jacques Lombet
- Division of Nephrology, Department of Pediatrics, University Hospital Center of Liège, Liège, Belgium
| | - Kathleen De Waele
- Department of Pediatric Endocrinology, University Hospital Ghent, Ghent, Belgium
| | - Charlotte Verroken
- Unit for Osteoporosis and Metabolic Bone Diseases, Department of Endocrinology and Metabolism, Ghent University Hospital, Ghent, Belgium
| | - Koenraad van Hoeck
- Department of Pediatric Nephrology, Antwerp University Hospital, Antwerp, Belgium
- Laboratory of Experimental Medicine and Pediatrics, University of Antwerp, Antwerp, Belgium
| | - Geert R. Mortier
- Department of Medical Genetics, Antwerp University Hospital and University of Antwerp, Antwerp, Belgium
| | - Elena Levtchenko
- Department of Pediatrics/Pediatric Nephrology, University Hospitals Leuven, Leuven, Belgium
| | - Johan Vande Walle
- Department of Pediatric Nephrology, University Hospital Ghent, Ghent, Belgium
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16
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Arango Sancho P. Complications of Phosphate and Vitamin D Treatment in X-Linked Hypophosphataemia. Adv Ther 2020; 37:105-112. [PMID: 32236871 DOI: 10.1007/s12325-019-01170-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Indexed: 01/01/2023]
Abstract
Conventional treatment of X-linked hypophosphataemia (XLH) consists in the oral administration of phosphate plus calcitriol supplements. Although this therapy has reduced bone deformities and even achieved adequate patient growth, overtreatment or low adherence could lead to subsequent consequences that may compromise the efficacy of the therapy. Some of the complications associated with phosphate and vitamin D treatment are abdominal discomfort, diarrhoea, hypokalaemia, hyperparathyroidism, hypercalcaemia or hypercalciuria, nephrocalcinosis or nephrolithiasis, and ectopic calcifications. Therefore, constant multidisciplinary monitoring of patients with XLH is necessary to prevent the manifestation of these complications and to deal with them as soon as they appear. The main objective of this article is to review the main complications arising from conventional treatment of XLH and how to deal with them.
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Affiliation(s)
- Pedro Arango Sancho
- Servicio de Nefrología Pediátrica y Trasplante Renal, Hospital Sant Joan de Déu, Barcelona, Spain.
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17
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Haffner D, Emma F, Eastwood DM, Duplan MB, Bacchetta J, Schnabel D, Wicart P, Bockenhauer D, Santos F, Levtchenko E, Harvengt P, Kirchhoff M, Di Rocco F, Chaussain C, Brandi ML, Savendahl L, Briot K, Kamenicky P, Rejnmark L, Linglart A. Clinical practice recommendations for the diagnosis and management of X-linked hypophosphataemia. Nat Rev Nephrol 2020; 15:435-455. [PMID: 31068690 PMCID: PMC7136170 DOI: 10.1038/s41581-019-0152-5] [Citation(s) in RCA: 260] [Impact Index Per Article: 65.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
X-linked hypophosphataemia (XLH) is the most common cause of inherited phosphate wasting and is associated with severe complications such as rickets, lower limb deformities, pain, poor mineralization of the teeth and disproportionate short stature in children as well as hyperparathyroidism, osteomalacia, enthesopathies, osteoarthritis and pseudofractures in adults. The characteristics and severity of XLH vary between patients. Because of its rarity, the diagnosis and specific treatment of XLH are frequently delayed, which has a detrimental effect on patient outcomes. In this Evidence-Based Guideline, we recommend that the diagnosis of XLH is based on signs of rickets and/or osteomalacia in association with hypophosphataemia and renal phosphate wasting in the absence of vitamin D or calcium deficiency. Whenever possible, the diagnosis should be confirmed by molecular genetic analysis or measurement of levels of fibroblast growth factor 23 (FGF23) before treatment. Owing to the multisystemic nature of the disease, patients should be seen regularly by multidisciplinary teams organized by a metabolic bone disease expert. In this article, we summarize the current evidence and provide recommendations on features of the disease, including new treatment modalities, to improve knowledge and provide guidance for diagnosis and multidisciplinary care. In this Evidence-Based Guideline on X-linked hypophosphataemia, the authors identify the criteria for diagnosis of this disease, provide guidance for medical and surgical treatment and explain the challenges of follow-up.
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Affiliation(s)
- Dieter Haffner
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover, Germany. .,Center for Congenital Kidney Diseases, Center for Rare Diseases, Hannover Medical School, Hannover, Germany.
| | - Francesco Emma
- Department of Pediatric Subspecialties, Division of Nephrology, Children's Hospital Bambino Gesù - IRCCS, Rome, Italy
| | - Deborah M Eastwood
- Department of Orthopaedics, Great Ormond St Hospital for Children, Orthopaedics, London, UK.,The Catterall Unit Royal National Orthopaedic Hospital NHS Trust, Stanmore, UK
| | - Martin Biosse Duplan
- Dental School, Université Paris Descartes Sorbonne Paris Cité, Montrouge, France.,APHP, Department of Odontology, Bretonneau Hospital, Paris, France.,APHP, Reference Center for Rare Diseases of Calcium and Phosphate Metabolism, and Filière OSCAR, Paris, France
| | - Justine Bacchetta
- Department of Pediatric Nephrology, Rheumatology and Dermatology, University Children's Hospital, Lyon, France
| | - Dirk Schnabel
- Center for Chronic Sick Children, Pediatric Endocrinology, Charitè, University Medicine, Berlin, Germany
| | - Philippe Wicart
- APHP, Reference Center for Rare Diseases of Calcium and Phosphate Metabolism, and Filière OSCAR, Paris, France.,APHP, Department of Pediatric Orthopedic Surgery, Necker - Enfants Malades University Hospital, Paris, France.,Paris Descartes University, Paris, France
| | - Detlef Bockenhauer
- University College London, Centre for Nephrology and Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Fernando Santos
- Hospital Universitario Central de Asturias (HUCA), University of Oviedo, Oviedo, Spain
| | - Elena Levtchenko
- Department of Pediatric Nephrology and Development and Regeneration, University Hospitals Leuven, University of Leuven, Leuven, Belgium
| | - Pol Harvengt
- RVRH-XLH, French Patient Association for XLH, Suresnes, France
| | - Martha Kirchhoff
- Phosphatdiabetes e.V., German Patient Association for XLH, Lippstadt, Germany
| | - Federico Di Rocco
- Pediatric Neurosurgery, Hôpital Femme Mère Enfant, Centre de Référence Craniosténoses, Université de Lyon, Lyon, France
| | - Catherine Chaussain
- Dental School, Université Paris Descartes Sorbonne Paris Cité, Montrouge, France.,APHP, Department of Odontology, Bretonneau Hospital, Paris, France.,APHP, Reference Center for Rare Diseases of Calcium and Phosphate Metabolism, and Filière OSCAR, Paris, France
| | - Maria Louisa Brandi
- Metabolic Bone Diseases Unit, Department of Surgery and Translational Medicine, University of Florence, Florence, Italy
| | - Lars Savendahl
- Pediatric Endocrinology Unit, Karolinska University Hospital, Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Karine Briot
- APHP, Reference Center for Rare Diseases of Calcium and Phosphate Metabolism, and Filière OSCAR, Paris, France.,Paris Descartes University, Paris, France.,APHP, Department of Rheumatology, Cochin Hospital, Paris, France.,INSERM UMR-1153, Paris, France
| | - Peter Kamenicky
- APHP, Reference Center for Rare Diseases of Calcium and Phosphate Metabolism, and Filière OSCAR, Paris, France.,APHP, Department of Endocrinology and Reproductive Diseases, Bicêtre Paris-Sud Hospital, Paris, France.,INSERM U1185, Bicêtre Paris-Sud, Paris-Sud - Paris Saclay University, Le Kremlin-Bicêtre, France
| | - Lars Rejnmark
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Agnès Linglart
- APHP, Reference Center for Rare Diseases of Calcium and Phosphate Metabolism, and Filière OSCAR, Paris, France.,INSERM U1185, Bicêtre Paris-Sud, Paris-Sud - Paris Saclay University, Le Kremlin-Bicêtre, France.,APHP, Platform of Expertise of Paris-Sud for Rare Diseases and Filière OSCAR, Bicêtre Paris-Sud Hospital (HUPS), Le Kremlin-Bicêtre, France.,APHP, Endocrinology and Diabetes for Children, Bicêtre Paris-Sud Hospital, Le Kremlin-Bicêtre, France
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18
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Lecoq AL, Brandi ML, Linglart A, Kamenický P. Management of X-linked hypophosphatemia in adults. Metabolism 2020; 103S:154049. [PMID: 31863781 DOI: 10.1016/j.metabol.2019.154049] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 10/23/2019] [Accepted: 11/25/2019] [Indexed: 11/27/2022]
Abstract
X-linked hypophosphatemia (XLH) is caused by mutations in the PHEX gene which result in Fibroblast Growth Factor-23 (FG-F23) excess and phosphate wasting. Clinically, XLH children present with rickets, bone deformities and short stature. In adulthood, patients may still be symptomatic with bone and joint pain, osteomalacia-related fractures or pseudofractures, precocious osteoarthrosis, enthesopathy, muscle weakness and severe dental anomalies. Besides these musculoskeletal and dental manifestations, adult XLH patients are also prone to secondary and tertiary hyperparathyroidism, cardiovascular and metabolic disorders. Pathophysiology of hyperparathyroidism is only partially understood but FGF23 excess and deficient production of calcitriol likely contributes to its development. Similarly, the pathophysiological mechanisms of potential cardiovascular and metabolic involvements are not clear, but FGF-23 excess may play an essential role. Treatment should be considered in symptomatic patients, patients undergoing orthopedic or dental surgery and women during pregnancy and lactation. Treatment with oral phosphate salts and active vitamin D analogs has incomplete efficacy and potential risks. Burosumab, a recombinant human monoclonal antibody against FGF-23, has proven its efficacy in phase 2 and phase 3 clinical trials in adult patients with XLH, but currently its position as first line or second line treatment differ among the countries.
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Affiliation(s)
- Anne-Lise Lecoq
- AP-HP, Department of Endocrinology and Reproductive Diseases, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, filière OSCAR, and Platform of Expertise for Rare Disorders, Bicêtre Paris Saclay Hospital, Le Kremlin-Bicêtre, France
| | - Maria Luisa Brandi
- Department of Surgery and Translational Medicine, University of Florence, University Hospital of Florence, Florence, Italy
| | - Agnès Linglart
- AP-HP, Endocrinology and Diabetes for Children, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, filière OSCAR, and Platform of Expertise for Rare Disorders, Bicêtre Paris Saclay Hospital, Le Kremlin-Bicêtre, France; Université Paris-Saclay, INSERM, Physiologie et Physiopathologie Endocriniennes, Le Kremlin-Bicêtre, France
| | - Peter Kamenický
- AP-HP, Department of Endocrinology and Reproductive Diseases, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, filière OSCAR, and Platform of Expertise for Rare Disorders, Bicêtre Paris Saclay Hospital, Le Kremlin-Bicêtre, France; Université Paris-Saclay, INSERM, Physiologie et Physiopathologie Endocriniennes, Le Kremlin-Bicêtre, France.
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DeLacey S, Liu Z, Broyles A, El-Azab SA, Guandique CF, James BC, Imel EA. Hyperparathyroidism and parathyroidectomy in X-linked hypophosphatemia patients. Bone 2019; 127:386-392. [PMID: 31276850 PMCID: PMC6836672 DOI: 10.1016/j.bone.2019.06.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 06/18/2019] [Accepted: 06/26/2019] [Indexed: 10/26/2022]
Abstract
BACKGROUND X-linked hypophosphatemia (XLH) causes rickets, osteomalacia, skeletal deformities and growth impairment, due to elevated fibroblast growth factor 23 and hypophosphatemia. Conventional therapy requires high doses of phosphate salts combined with active vitamin D analogues. Risks of this regimen include nephrocalcinosis and secondary hyperparathyroidism or progression to tertiary (hypercalcemic) hyperparathyroidism. METHODS The primary goals were to estimate the prevalence of hyperparathyroidism and to characterize parathyroidectomy outcomes regarding hypercalcemia among XLH patients. XLH patients attending our center from 1/2000 to 12/2017 were included in a retrospective chart review. Prevalence of nephrocalcinosis and eGFR < 60 ml/min/1.73m2 was also assessed. RESULTS Of 104 patients with XLH, 84 had concurrent measurements of calcium and PTH (40 adults and 44 children). Of these, 70/84 (83.3%), had secondary or tertiary hyperparathyroidism at any time point. Secondary hyperparathyroidism was persistent in 62.2% of those with data at multiple timepoints. Tertiary hyperparathyroidism had an overall prevalence of 14/84 (16.7%) patients. Parathyroidectomy was performed in 8/84 (9.5%) of the total population. After parathyroidectomy, persistent or recurrent tertiary hyperparathyroidism was detected in 6/8 (75%) patients at a median of 6 years (from 0 to 29 years). One patient had chronic post-surgical hypoparathyroidism and one patient remained normocalcemic 4 years after surgery. Nephrocalcinosis was more prevalent in patients with tertiary hyperparathyroidism than those without (60.0% vs 18.6%). Chronic kidney disease (eGFR < 60 ml/min/1.73m2) was also more prevalent in patients with tertiary hyperparathyroidism than those without (35.7% vs 1.5%). CONCLUSION The majority of patients with XLH develop secondary hyperparathyroidism during treatment with phosphate and active vitamin D. A significant proportion develops tertiary hyperparathyroidism and most have recurrence or persistence of hypercalcemia after surgery.
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Affiliation(s)
- Sean DeLacey
- Indiana University School of Medicine, Department of Medicine, United States of America; Indiana University School of Medicine, Department of Pediatrics, United States of America
| | - Ziyue Liu
- Indiana University School of Public Health, Department of Biostatistics, United States of America
| | - Andrea Broyles
- Regenstrief Institute, Data Core Services, United States of America
| | - Sarah A El-Azab
- Regenstrief Institute, Data Core Services, United States of America
| | | | - Benjamin C James
- Harvard Medical School, Beth Israel Deaconess Medical Center, Department of Surgery, United States of America
| | - Erik A Imel
- Indiana University School of Medicine, Department of Medicine, United States of America; Indiana University School of Medicine, Department of Pediatrics, United States of America.
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Risk of cardiovascular involvement in pediatric patients with X-linked hypophosphatemia. Pediatr Nephrol 2019; 34:1077-1086. [PMID: 30607568 DOI: 10.1007/s00467-018-4180-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 11/29/2018] [Accepted: 12/13/2018] [Indexed: 12/15/2022]
Abstract
OBJECTIVE To find out if cardiovascular alterations are present in pediatric patients with X-linked hypophosphatemia (XLH). STUDY DESIGN Multicentre prospective clinical study on pediatric patients included in the RenalTube database ( www.renaltube.com ) with genetically confirmed diagnosis of XLH by mutations in the PHEX gene. The study's protocol consisted of biochemical work-up, 24-h ambulatory blood pressure monitoring (ABPM), carotid ultrasonography, and echocardiogram. All patients were on chronic treatment with phosphate supplements and 1-hydroxy vitamin D metabolites. RESULTS Twenty-four patients (17 females, from 1 to 17 years of age) were studied. Serum concentrations (X ± SD) of phosphate and intact parathyroid hormone were 2.66 ± 0.60 mg/dl and 58.3 ± 26.8 pg/ml, respectively. Serum fibroblast growth factor 23 (FGF23) concentration was 278.18 ± 294.45 pg/ml (normal < 60 pg/ml). Abnormally high carotid intima media thickness was found in one patient, who was obese and hypertensive as revealed by ABPM, which disclosed arterial hypertension in two other patients. Z scores for echocardiographic interventricular septum end diastole and left ventricular posterior wall end diastole were + 0.77 ± 0.77 and + 0.94 ± 0.86, respectively. Left ventricular mass index (LVMI) was 44.93 ± 19.18 g/m2.7, and four patients, in addition to the obese one, had values greater than 51 g/m2.7, indicative of left ventricular hypertrophy. There was no correlation between these echocardiographic parameters and serum FGF23 concentrations. CONCLUSIONS XLH pediatric patients receiving conventional treatment have echocardiographic measurements of ventricular mass within normal reference values, but above the mean, and 18% have LVMI suggestive of left ventricular hypertrophy without correlation with serum FGF23 concentrations. This might indicate an increased risk of cardiovascular involvement in XLH.
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Beck-Nielsen SS, Mughal Z, Haffner D, Nilsson O, Levtchenko E, Ariceta G, de Lucas Collantes C, Schnabel D, Jandhyala R, Mäkitie O. FGF23 and its role in X-linked hypophosphatemia-related morbidity. Orphanet J Rare Dis 2019; 14:58. [PMID: 30808384 PMCID: PMC6390548 DOI: 10.1186/s13023-019-1014-8] [Citation(s) in RCA: 138] [Impact Index Per Article: 27.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 01/30/2019] [Indexed: 12/29/2022] Open
Abstract
Background X-linked hypophosphatemia (XLH) is an inherited disease of phosphate metabolism in which inactivating mutations of the Phosphate Regulating Endopeptidase Homolog, X-Linked (PHEX) gene lead to local and systemic effects including impaired growth, rickets, osteomalacia, bone abnormalities, bone pain, spontaneous dental abscesses, hearing difficulties, enthesopathy, osteoarthritis, and muscular dysfunction. Patients with XLH present with elevated levels of fibroblast growth factor 23 (FGF23), which is thought to mediate many of the aforementioned manifestations of the disease. Elevated FGF23 has also been observed in many other diseases of hypophosphatemia, and a range of animal models have been developed to study these diseases, yet the role of FGF23 in the pathophysiology of XLH is incompletely understood. Methods The role of FGF23 in the pathophysiology of XLH is here reviewed by describing what is known about phenotypes associated with various PHEX mutations, animal models of XLH, and non-nutritional diseases of hypophosphatemia, and by presenting molecular pathways that have been proposed to contribute to manifestations of XLH. Results The pathophysiology of XLH is complex, involving a range of molecular pathways that variously contribute to different manifestations of the disease. Hypophosphatemia due to elevated FGF23 is the most obvious contributor, however localised fluctuations in tissue non-specific alkaline phosphatase (TNAP), pyrophosphate, calcitriol and direct effects of FGF23 have been observed to be associated with certain manifestations. Conclusions By describing what is known about these pathways, this review highlights key areas for future research that would contribute to the understanding and clinical treatment of non-nutritional diseases of hypophosphatemia, particularly XLH.
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Affiliation(s)
| | - Zulf Mughal
- Royal Manchester Children's Hospital, Manchester, UK
| | | | - Ola Nilsson
- Karolinska Institutet, Stockholm, Sweden and Örebro University, Örebro, Sweden
| | | | - Gema Ariceta
- Hospital Universitario Materno-Infantil Vall d'Hebron, Universitat Autonoma de Barcelona, Barcelona, Spain
| | | | - Dirk Schnabel
- University Children's Hospital of Berlin, Berlin, Germany
| | | | - Outi Mäkitie
- Children's Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
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Abstract
Rickets refers to deficient mineralization at the growth plate and is usually associated with abnormal serum calcium and/or phosphate. There are several subtypes of rickets, including hypophosphatemic rickets (vitamin-D-resistant rickets secondary to renal phosphate wasting), vitamin D-dependent rickets (defects of vitamin D metabolism) and nutritional rickets (caused by dietary deficiency of vitamin D, and/or calcium, and/or phosphate). Most rickets manifest as bone deformities, bone pain, and impaired growth velocity. Diagnosis of rickets is established through the medical history, physical examination, biochemical tests and radiographs. It is of crucial importance to determine the cause of rickets, including the molecular characterization in case of vitamin D resistant rickets, and initiate rapidly the appropriate therapy. In this review, we describe the different causes and therapies of genetic and nutritional rickets, supported by the recent progress in genetics and development of novel molecules such as anti-FGF23 antibody.
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Affiliation(s)
- A S Lambert
- APHP, Department of Pediatric Endocrinology and Diabetology for Children, Bicêtre Paris-Sud, Le Kremlin-Bicêtre, France; APHP, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, Filière OSCAR and Plateforme D'Expertise Maladies Rares Paris-Sud, Bicêtre Paris-Sud, Le Kremlin Bicêtre, France.
| | - A Linglart
- APHP, Department of Pediatric Endocrinology and Diabetology for Children, Bicêtre Paris-Sud, Le Kremlin-Bicêtre, France; APHP, Reference Center for Rare Disorders of Calcium and Phosphate Metabolism, Filière OSCAR and Plateforme D'Expertise Maladies Rares Paris-Sud, Bicêtre Paris-Sud, Le Kremlin Bicêtre, France
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Abstract
Rickets is a metabolic bone disease that develops as a result of inadequate mineralization of growing bone due to disruption of calcium, phosphorus and/or vitamin D metabolism. Nutritional rickets remains a significant child health problem in developing countries. In addition, several rare genetic causes of rickets have also been described, which can be divided into two groups. The first group consists of genetic disorders of vitamin D biosynthesis and action, such as vitamin D-dependent rickets type 1A (VDDR1A), vitamin D-dependent rickets type 1B (VDDR1B), vitamin D-dependent rickets type 2A (VDDR2A), and vitamin D-dependent rickets type 2B (VDDR2B). The second group involves genetic disorders of excessive renal phosphate loss (hereditary hypophosphatemic rickets) due to impairment in renal tubular phosphate reabsorption as a result of FGF23-related or FGF23-independent causes. In this review, we focus on clinical, laboratory and genetic characteristics of various types of hereditary rickets as well as differential diagnosis and treatment approaches.
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Affiliation(s)
- Sezer Acar
- Dokuz Eylül University Faculty of Medicine, Department of Pediatric Endocrinology, İzmir, Turkey
| | - Korcan Demir
- Dokuz Eylül University Faculty of Medicine, Department of Pediatric Endocrinology, İzmir, Turkey
| | - Yufei Shi
- King Faisal Specialist Hospital & Research Centre, Department of Genetics, Riyadh, Saudi Arabia
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Nakamura Y, Takagi M, Takeda R, Miyai K, Hasegawa Y. Hypertension is a characteristic complication of X-linked hypophosphatemia. Endocr J 2017; 64:283-289. [PMID: 28025445 DOI: 10.1507/endocrj.ej16-0199] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
X-linked hypophosphatemia (XLH) is a group of rare disorders caused by defective proximal tubular reabsorption of phosphate. Mutations in the PHEX gene are responsible for the majority of cases. There are very few reports of long-term complications of XLH other than skeletal and dental diseases. The aim of this study was to identify the phenotypic presentation of XLH during adulthood including complications other than skeletal and dental diseases. The clinical and biochemical phenotype of 22 adult patients with a PHEX gene mutation were examined retrospectively from their medical records. 6 patients had hypertension. The average age of hypertension onset was 29.0 years. Secondary hyperparathyroidism preceded the development of hypertension in 5 patients. 1 patient developed tertiary hyperparathyroidism. 15 patients had nephrocalcinosis. 2 patients had chronic renal dysfunction. Patients with hypertension had a significantly lower eGFR (p=0.010) compared to patients without hypertension. No significant difference was found in any other parameters. To examine the genotype-phenotype correlation, 10 adult males were chosen for analysis. No significant genotype-phenotype correlation analysis was revealed in any of the complications. However, there was a possibility that the age at nephrocalcinosis onset was younger in the non-missense mutation group than in the missense mutation group (p=0.063). This study corroborated the view that early-onset hypertension could be one of the characteristic complications seen in XLH patients. Considering the limited number of our patients, further study is necessary to address a potential cause of hypertension. XLH patients require careful lifelong treatment.
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Affiliation(s)
- Yoshie Nakamura
- Division of Genetic Research, Tokyo Metropolitan Children's Medical Center, Tokyo 183-8561, Japan
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Rafaelsen S, Johansson S, Ræder H, Bjerknes R. Hereditary hypophosphatemia in Norway: a retrospective population-based study of genotypes, phenotypes, and treatment complications. Eur J Endocrinol 2016; 174:125-36. [PMID: 26543054 PMCID: PMC4674593 DOI: 10.1530/eje-15-0515] [Citation(s) in RCA: 101] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Accepted: 11/04/2015] [Indexed: 01/14/2023]
Abstract
OBJECTIVE Hereditary hypophosphatemias (HH) are rare monogenic conditions characterized by decreased renal tubular phosphate reabsorption. The aim of this study was to explore the prevalence, genotypes, phenotypic spectrum, treatment response, and complications of treatment in the Norwegian population of children with HH. DESIGN Retrospective national cohort study. METHODS Sanger sequencing and multiplex ligand-dependent probe amplification analysis of PHEX and Sanger sequencing of FGF23, DMP1, ENPP1KL, and FAM20C were performed to assess genotype in patients with HH with or without rickets in all pediatric hospital departments across Norway. Patients with hypercalcuria were screened for SLC34A3 mutations. In one family, exome sequencing was performed. Information from the patients' medical records was collected for the evaluation of phenotype. RESULTS Twety-eight patients with HH (18 females and ten males) from 19 different families were identified. X-linked dominant hypophosphatemic rickets (XLHR) was confirmed in 21 children from 13 families. The total number of inhabitants in Norway aged 18 or below by 1st January 2010 was 1,109,156, giving an XLHR prevalence of ∼1 in 60,000 Norwegian children. FAM20C mutations were found in two brothers and SLC34A3 mutations in one patient. In XLHR, growth was compromised in spite of treatment with oral phosphate and active vitamin D compounds, with males tending to be more affected than females. Nephrocalcinosis tended to be slightly more common in patients starting treatment before 1 year of age, and was associated with higher average treatment doses of phosphate. However, none of these differences reached statistical significance. CONCLUSIONS We present the first national cohort of HH in children. The prevalence of XLHR seems to be lower in Norwegian children than reported earlier.
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Affiliation(s)
- Silje Rafaelsen
- Section for PediatricsDepartment of Clinical Science, Haukeland University Hospital, University of Bergen, N-5021 Bergen, NorwayCenter for Medical Genetics and Molecular MedicineDepartment of PediatricsHaukeland University Hospital, Bergen, Norway
| | - Stefan Johansson
- Section for PediatricsDepartment of Clinical Science, Haukeland University Hospital, University of Bergen, N-5021 Bergen, NorwayCenter for Medical Genetics and Molecular MedicineDepartment of PediatricsHaukeland University Hospital, Bergen, Norway Section for PediatricsDepartment of Clinical Science, Haukeland University Hospital, University of Bergen, N-5021 Bergen, NorwayCenter for Medical Genetics and Molecular MedicineDepartment of PediatricsHaukeland University Hospital, Bergen, Norway
| | - Helge Ræder
- Section for PediatricsDepartment of Clinical Science, Haukeland University Hospital, University of Bergen, N-5021 Bergen, NorwayCenter for Medical Genetics and Molecular MedicineDepartment of PediatricsHaukeland University Hospital, Bergen, Norway Section for PediatricsDepartment of Clinical Science, Haukeland University Hospital, University of Bergen, N-5021 Bergen, NorwayCenter for Medical Genetics and Molecular MedicineDepartment of PediatricsHaukeland University Hospital, Bergen, Norway
| | - Robert Bjerknes
- Section for PediatricsDepartment of Clinical Science, Haukeland University Hospital, University of Bergen, N-5021 Bergen, NorwayCenter for Medical Genetics and Molecular MedicineDepartment of PediatricsHaukeland University Hospital, Bergen, Norway Section for PediatricsDepartment of Clinical Science, Haukeland University Hospital, University of Bergen, N-5021 Bergen, NorwayCenter for Medical Genetics and Molecular MedicineDepartment of PediatricsHaukeland University Hospital, Bergen, Norway
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Diener S, Schorpp K, Strom TM, Hadian K, Lorenz-Depiereux B. Development of A Cell-Based Assay to Identify Small Molecule Inhibitors of FGF23 Signaling. Assay Drug Dev Technol 2015; 13:476-87. [DOI: 10.1089/adt.2015.653] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Affiliation(s)
- Susanne Diener
- German Research Center for Environmental Health, Institute of Human Genetics, HelmholtzZentrum München, Neuherberg, Bavaria, Germany
| | - Kenji Schorpp
- Assay Development and Screening Platform, German Research Center for Environmental Health, Institute of Molecular Toxicology and Pharmacology, HelmholtzZentrum München, Neuherberg, Bavaria, Germany
| | - Tim-Matthias Strom
- German Research Center for Environmental Health, Institute of Human Genetics, HelmholtzZentrum München, Neuherberg, Bavaria, Germany
- Institute of Human Genetics, Klinikum rechts der Isar der Technischen Universität München, Munich, Bavaria, Germany
| | - Kamyar Hadian
- Assay Development and Screening Platform, German Research Center for Environmental Health, Institute of Molecular Toxicology and Pharmacology, HelmholtzZentrum München, Neuherberg, Bavaria, Germany
| | - Bettina Lorenz-Depiereux
- German Research Center for Environmental Health, Institute of Human Genetics, HelmholtzZentrum München, Neuherberg, Bavaria, Germany
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Hypophosphatemic rickets: etiology, clinical features and treatment. EUROPEAN JOURNAL OF ORTHOPAEDIC SURGERY AND TRAUMATOLOGY 2014; 25:221-6. [DOI: 10.1007/s00590-014-1496-y] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Accepted: 06/02/2014] [Indexed: 02/02/2023]
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Penido MGMG, Alon US. Hypophosphatemic rickets due to perturbations in renal tubular function. Pediatr Nephrol 2014; 29:361-73. [PMID: 23636577 DOI: 10.1007/s00467-013-2466-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2012] [Revised: 03/03/2013] [Accepted: 03/04/2013] [Indexed: 12/13/2022]
Abstract
The common denominator for all types of rickets is hypophosphatemia, leading to inadequate supply of the mineral to the growing bone. Hypophosphatemia can result from insufficient uptake of the mineral from the gut or its disproportionate losses in the kidney, the latter being caused by either tubular abnormalities per se or the effect on the tubule of circulating factors like fibroblast growth factor-23 and parathyroid hormone (PTH). High serum levels of the latter result in most cases from abnormalities in vitamin D metabolism which lead to decreased calcium absorption in the gut and hypocalcemia, triggering PTH secretion. Rickets is a disorder of the growth plate and hence pediatric by definition. However, it is important to recognize that the effect of hypophosphatemia on other parts of the skeleton results in osteomalacia in both children and adults. This review addresses the etiology, pathophysiologic mechanisms, clinical manifestations and treatment of entities associated with hypophosphatemic rickets due to perturbations in renal tubular function.
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Affiliation(s)
- Maria Goretti M G Penido
- Pediatric Nephrology Unit, Clinics Hospital, School of Medicine, Federal University of Minas Gerais, Av. Professor Alfredo Balena, 190, CEP, 30130100, Belo Horizonte, MG, Brazil,
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Three-year successful cinacalcet treatment of secondary hyperparathyroidism in a patient with x-linked dominant hypophosphatemic rickets: a case report. Case Rep Endocrinol 2014; 2014:479641. [PMID: 24660072 PMCID: PMC3934321 DOI: 10.1155/2014/479641] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Accepted: 01/03/2014] [Indexed: 11/18/2022] Open
Abstract
Hypophosphatemic rickets (HR) is a rare inherited disorder characterized by a classic rickets phenotype with low plasma phosphate levels and resistance to treatment with vitamin D. Development of secondary hyperparathyroidism (SHPT) as a direct consequence of treatment is a frequent complication and a major clinical challenge, as this may increase risk of further comorbidity. Cinacalcet, a calcimimetic agent that reduces the secretion of PTH from the parathyroid glands, has been suggested as adjuvant treatment to SHPT in patients with HR. However, only two papers have previously been published and no data are available on effects of treatment for more than six months. We now report a case of 3-year treatment with cinacalcet in a patient with HR complicated by SHPT. A 53-year-old woman with genetically confirmed X-linked dominant hypophosphatemic rickets developed SHPT after 25 years of conventional treatment with alfacalcidol and phosphate supplements. Cinacalcet was added to her treatment, causing a sustained normalization of PTH. Ionized calcium decreased, requiring reduction of cinacalcet, though asymptomatical. Level of phosphate was unchanged, but alkaline phosphatase increased in response to treatment. Cinacalcet appeared to be efficient, safe, and well tolerated. We recommend close control of plasma calcium to avoid hypocalcemia.
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Familial hypophosphatemia: an unusual presentation with low back ache, heel pain, and a limp in a young man, and literature review. Clin Rheumatol 2010; 30:585-9. [PMID: 21042824 DOI: 10.1007/s10067-010-1607-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2010] [Accepted: 10/13/2010] [Indexed: 10/18/2022]
Abstract
A case of young man with low back ache and heel pains who was examined in a rheumatology outpatient and diagnosed as familial hypophosphatemia (FH), probably X-linked (XL), is presented. FH is most commonly transmitted as XL. The role of PHEX gene and fibroblast growth factor 23 is also described.
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Raeder H, Shaw N, Netelenbos C, Bjerknes R. A case of X-linked hypophosphatemic rickets: complications and the therapeutic use of cinacalcet. Eur J Endocrinol 2008; 159 Suppl 1:S101-5. [PMID: 18775977 DOI: 10.1530/eje-08-0383] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In hypophosphatemic rickets, there are both inherited and acquired forms, where X-linked dominant hypophosphatemic rickets (XLH) is the most prevalent genetic form and caused by mutations in the phosphate-regulating endopeptidase (PHEX) gene. XLH is associated with growth retardation and bone deformities. The renal tubular cells have an important role in calcium and phosphate metabolism, where the 1alpha-hydroxylase enzyme metabolizes the conversion of 25 (OH)-vitamin D to potent 1,25 (OH)2-vitamin D, whereas the sodium-phosphate transporter controls tubular phosphate reabsorption. The pathophysiological defect in XLH is speculated to cause an increase in a circulating phosphate regulating hormone termed phosphatonin (fibroblast growth factor 23 is the primary phosphatonin candidate), which leads to inhibition of 1alpha-hydroxylase, and simultaneously to inhibition of the sodium-phosphate transporter domain NPT2c leading to parathyroid hormone-independent phosphaturia. Hence, current treatment of XLH is 1,25 (OH)2-vitamin D or the vitamin D analog alfacalcidol and elementary phosphorus. Unfortunately, patients with XLH may develop nephrocalcinosis, secondary or tertiary hyperparathyroidism, and in some situations also hypertension and cardiovascular abnormalities. We describe a patient with XLH caused by a novel missense mutation in the PHEX gene, who on treatment with alfacalcidol and oral phosphate had normal growth and minimal bone deformities, but who subsequently developed moderate nephrocalcinosis, significant hyperparathyroidism, hypercalcemia, renal failure, and hypertension. We also report the use of the calcimimetic drug cinacalcet in the successful treatment of hypercalcemia and hyperparathyroidism.
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Affiliation(s)
- Helge Raeder
- Section for Pediatrics, Department of Clinical Medicine, University of Bergen, 5021 Bergen, Norway.
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Alon US, Levy-Olomucki R, Moore WV, Stubbs J, Liu S, Quarles LD. Calcimimetics as an adjuvant treatment for familial hypophosphatemic rickets. Clin J Am Soc Nephrol 2008; 3:658-64. [PMID: 18256372 DOI: 10.2215/cjn.04981107] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND AND OBJECTIVES The treatment for X-linked hypophosphatemia (XLH) with phosphate and calcitriol can be complicated by secondary hyperparathyroidism and nephrocalcinosis. Furthermore, vitamin D and phosphate stimulate FGF23 production, the pathogenic factor causing XLH. We investigated in XLH patients: 1) whether treatment with the calcimimetic agent, cinacalcet, will block the rise in parathyroid hormone (PTH) caused by phosphate administration; and 2) whether treatment with oral phosphate and calcitriol increases FGF23 levels. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS Eight subjects with XLH were given a single oral dose of phosphate, followed the next day by combined treatment with phosphate and cinacalcet. Serum measurements of ionized calcium (Ca), phosphate, creatinine, intact PTH, 1,25(OH)(2)D, FGF23, and tubular threshold for phosphate/glomerular filtration rate (TP/GFR) were assessed in response to short-term treatment with phosphate and cinacalcet and compared with long-term administration of phosphate and calcitriol. RESULTS Oral phosphate load increased serum phosphate, decreased ionized calcium, and increased PTH. Twenty-four hours later, FGF23 significantly increased and 1,25(OH)(2)D decreased. The concomitant administration of phosphate and cinacalcet resulted in further decrease in serum Ca(2+) but suppression of PTH and greater increase in serum phosphate and TP/GFR. Chronic treatment with phosphate and calcitriol resulted in a smaller increment in serum phosphate and high serum FGF23. CONCLUSIONS Traditional therapy of XLH with phosphate and calcitriol elevates FGF23 and has the potential to stimulate PTH. Short-term treatment with cinacalcet suppresses PTH, leading to increase in TP/GFR and serum phosphate. Thus, long-term clinical studies are needed to investigate whether cinacalcet may be a useful adjuvant in the treatment of XLH, allowing the use of lower doses of phosphate and calcitriol.
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Affiliation(s)
- Uri S Alon
- Pediatric Nephrology, Bone and Mineral Disorders Clinic, Children's Mercy Hospital, University of Missouri, Kansas City, MO 64108, USA.
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de Menezes Filho H, de Castro LCG, Damiani D. Hypophosphatemic rickets and osteomalacia. ACTA ACUST UNITED AC 2007; 50:802-13. [PMID: 17117305 DOI: 10.1590/s0004-27302006000400025] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2006] [Accepted: 05/08/2006] [Indexed: 01/31/2023]
Abstract
The hypophosphatemic conditions that interfere in bone mineralization comprise many hereditary or acquired diseases, all of them sharing the same pathophysiologic mechanism: reduction in the phosphate reabsorption by the renal tubuli. This process leads to chronic hyperphosphaturia and hypophosphatemia, associated with inappropriately normal or low levels of calcitriol, causing osteomalacia or rickets in children and osteomalacia in adults. X-linked hypophosphatemic rickets, autosomal-dominant hypophosphatemic rickets, and tumor-induced osteomalacia are the main syndromes involved in the hypophosphatemic rickets. Although these conditions exhibit different etiologies, there is a common link among them: increased activity of a phosphaturic factor, being the fibroblast growth factor 23 (FGF-23) the most studied one and to which is attributed a central role in the pathophysiology of the hyperphosphaturic disturbances. Activating mutations of FGF-23 and inactivating mutations in the PHEX gene (a gene on the X chromosome that codes for a Zn-metaloendopeptidase proteolytic enzyme which regulates the phosphate) involved in the regulation of FGF-23 have been identified and have been implicated in the pathogenesis of these disturbances. Genetic studies tend to show that the phosphorus homeostasis depends on a complex osteo-renal metabolic axis, whose mechanisms of interaction have been poorly understood so far. This paper reviews the current knowledge status concerning the pathophysiology of phosphate metabolism regulation and the pathophysiologic basis of hypophosphatemic rickets. It also analyzes the clinical picture and the therapeutic aspects of these conditions as well.
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Affiliation(s)
- Hamilton de Menezes Filho
- Instituto da Criança, Hospital das Clínicas, Medical School, São Paulo University, São Paulo, SP, Brazil
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Cho HY, Lee BH, Kang JH, Ha IS, Cheong HI, Choi Y. A clinical and molecular genetic study of hypophosphatemic rickets in children. Pediatr Res 2005; 58:329-33. [PMID: 16055933 DOI: 10.1203/01.pdr.0000169983.40758.7b] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
X-linked hypophosphatemic rickets (XLH), autosomal dominant hypophosphatemic rickets, hereditary hypophosphatemic rickets with hypercalciuria, and tumor-induced osteomalacia share clinical and biochemical features, and are collectively referred to as hypophosphatemic rickets (HR). Recently, the molecular bases of HR were elucidated. A review of medical records and mutational analyses of the PHEX and FGF23 genes were performed on 17 unrelated Korean children with HR. The male-to-female ratio was 3:14, and 5 patients were familial. Initial laboratory tests revealed typical features of HR. Seven different PHEX mutations were detected in 8 patients: 2 missense mutations, 2 nonsense mutations, and 3 short deletions. No functional FGF23 mutation was detected in any patient. Patients with the PHEX mutation tended to have more severe skeletal disease than those without. Of the patients with this mutation, no genotype-phenotype correlation and no gene dosage effect were noted. Treatment with vitamin D and phosphate resulted in only a partial growth improvement in most cases, and was frequently complicated by hypercalciuria, hypercalcemia, nephrocalcinosis, or hyperparathyroidism. Renal glycosuria was detected in six cases and was associated with more severe skeletal disease. We conclude that current HR treatment is not fully safe or effective, and that close monitoring of treatment effectiveness and for complications should be performed during long-term treatment. No genotype-phenotype correlation in XLH was detected in this study, but a large-scaled study on this topic is warranted. The large proportion of patients with a normal genetic study suggests the possibility of other causative gene(s).
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Affiliation(s)
- Hee Y Cho
- Department of Pediatrics, Seoul National University Children's Hospital, Seoul 110-744, Korea
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Imel EA, Econs MJ. Fibroblast Growth Factor 23: Roles in Health and Disease: Figure 1. J Am Soc Nephrol 2005; 16:2565-75. [PMID: 16033853 DOI: 10.1681/asn.2005050573] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Erik A Imel
- Department of Medicine, Division of Endocrinology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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