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Zhu Z, Bo-Ran Ho B, Chen A, Amrhein J, Apetrei A, Carpenter TO, Lazaretti-Castro M, Colazo JM, McCrystal Dahir K, Geßner M, Gurevich E, Heier CA, Simmons JH, Hunley TE, Hoppe B, Jacobsen C, Kouri A, Ma N, Majumdar S, Molin A, Nokoff N, Ott SM, Peña HG, Santos F, Tebben P, Topor LS, Deng Y, Bergwitz C. An update on clinical presentation and responses to therapy of patients with hereditary hypophosphatemic rickets with hypercalciuria (HHRH). Kidney Int 2024; 105:1058-1076. [PMID: 38364990 DOI: 10.1016/j.kint.2024.01.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2023] [Revised: 12/23/2023] [Accepted: 01/08/2024] [Indexed: 02/18/2024]
Abstract
Pathogenic variants in solute carrier family 34, member 3 (SLC34A3), the gene encoding the sodium-dependent phosphate cotransporter 2c (NPT2c), cause hereditary hypophosphatemic rickets with hypercalciuria (HHRH). Here, we report a pooled analysis of clinical and laboratory records of 304 individuals from 145 kindreds, including 20 previously unreported HHRH kindreds, in which two novel SLC34A3 pathogenic variants were identified. Compound heterozygous/homozygous carriers show above 90% penetrance for kidney and bone phenotypes. The biochemical phenotype for heterozygous carriers is intermediate with decreased serum phosphate, tubular reabsorption of phosphate (TRP (%)), fibroblast growth factor 23, and intact parathyroid hormone, but increased serum 1,25-dihydroxy vitamin D, and urine calcium excretion causing idiopathic hypercalciuria in 38%, with bone phenotypes still observed in 23% of patients. Oral phosphate supplementation is the current standard of care, which typically normalizes serum phosphate. However, although in more than half of individuals this therapy achieves correction of hypophosphatemia it fails to resolve the other outcomes. The American College of Medical Genetics and Genomics score correlated with functional analysis of frequent SLC34A3 pathogenic variants in vitro and baseline disease severity. The number of mutant alleles and baseline TRP (%) were identified as predictors for kidney and bone phenotypes, baseline TRP (%) furthermore predicted response to therapy. Certain SLC34A3/NPT2c pathogenic variants can be identified with partial responses to therapy, whereas with some overlap, others present only with kidney phenotypes and a third group present only with bone phenotypes. Thus, our report highlights important novel clinical aspects of HHRH and heterozygous carriers, raises awareness to this rare group of disorders and can be a foundation for future studies urgently needed to guide therapy of HHRH.
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Affiliation(s)
- Zewu Zhu
- Department of Internal Medicine, Section of Endocrinology, Yale University School of Medicine, New Haven, Connecticut, USA; Department of Urology, Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Bryan Bo-Ran Ho
- Department of Internal Medicine, Section of Endocrinology, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Alyssa Chen
- Department of Internal Medicine, Section of Endocrinology, Yale University School of Medicine, New Haven, Connecticut, USA; Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts, USA
| | - James Amrhein
- Pediatric Endocrinology and Diabetes, School of Medicine Greenville Campus, University of South Carolina, Greenville, South Carolina, USA
| | - Andreea Apetrei
- Caen University Hospital, Department of Genetics, UR7450 Biotargen, Reference Center for Rare Diseases of Calcium and Phosphate Metabolism, OSCAR Network, Caen, France
| | - Thomas Oliver Carpenter
- Department of Internal Medicine, Section of Endocrinology, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Marise Lazaretti-Castro
- Division of Endocrinology, Escola Paulista de Medicina-Universidade Federal de Sao Paulo (EPM-UNIFESP), Sao Paulo, Brazil
| | - Juan Manuel Colazo
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee, USA
| | - Kathryn McCrystal Dahir
- Division of Endocrinology, Program for Metabolic Bone Disorders, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Michaela Geßner
- Pediatric Nephrology, Children's and Adolescents' Hospital, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Evgenia Gurevich
- Schneider Children's Medical Center of Israel, Pediatric Nephrology Institute, Petach Tikva, Israel; Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel
| | | | - Jill Hickman Simmons
- Department of Pediatrics, Division of Endocrinology and Diabetes, Vanderbilt University School of Medicine, Vanderbilt University, Nashville, Tennessee, USA
| | - Tracy Earl Hunley
- Division of Pediatric Nephrology, Vanderbilt University Medical Center, Monroe Carell Jr Children's Hospital at Vanderbilt, Nashville, Tennessee, USA
| | - Bernd Hoppe
- Division of Pediatric Nephrology, Department of Pediatrics, University of Bonn, Bonn, Germany
| | - Christina Jacobsen
- Division of Endocrinology, Harvard Medical School, Boston, Massachusetts, USA
| | - Anne Kouri
- Pediatric Nephrology, University of Minnesota, Minneapolis, Minnesota, USA
| | - Nina Ma
- Section of Pediatric Endocrinology, Children's Hospital Colorado, Aurora, Colorado, USA; Department of Pediatrics, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Sachin Majumdar
- Department of Internal Medicine, Section of Endocrinology, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Arnaud Molin
- Caen University Hospital, Department of Genetics, UR7450 Biotargen, Reference Center for Rare Diseases of Calcium and Phosphate Metabolism, OSCAR Network, Caen, France
| | - Natalie Nokoff
- Department of Pediatrics, Section of Endocrinology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - Susan M Ott
- Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Helena Gil Peña
- Department of Pediatrics, Hospital Universitario Central de Asturias (HUCA), Oviedo, Spain
| | - Fernando Santos
- Department of Pediatrics, Hospital Universitario Central de Asturias (HUCA), Oviedo, Spain
| | - Peter Tebben
- Division of Endocrinology, Diabetes, Metabolism, and Nutrition, Mayo Clinic, Rochester, Minnesota, USA; Division of Pediatric Endocrinology, Mayo Clinic, Rochester, Minnesota, USA
| | - Lisa Swartz Topor
- Division of Pediatric Endocrinology, Hasbro Children's Hospital, Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA
| | - Yanhong Deng
- Yale School of Public Health, New Haven, Connecticut, USA
| | - Clemens Bergwitz
- Department of Internal Medicine, Section of Endocrinology, Yale University School of Medicine, New Haven, Connecticut, USA.
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Wang L, Kulaixi G, Zaiyinati J, Aibai G, Du D, Guo Y. Family analysis and literature study of hereditary hypophosphatemic rickets with hypercalciuria. BMC Pediatr 2024; 24:121. [PMID: 38355430 PMCID: PMC10865686 DOI: 10.1186/s12887-024-04589-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Accepted: 01/24/2024] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND Hereditary hypophosphatemia rickets with hypercalciuria (HHRH) is a rare autosomal recessive disorder characterised by reduced renal phosphate reabsorption leading to hypophosphataemia, rickets and bone pain. Here, we present a case of HHRH in a Chinese boy. CASE PRESENTATION We report a 11-year-old female proband, who was admitted to our hospital with bilateral genuvarum deformity and short stature. Computed Tomography (CT) showed kidney stones, blood tests showed hypophosphatemia, For a clear diagnosis, we employed high-throughput sequencing technology to screen for variants. Our gene sequencing approach encompassed whole exome sequencing, detection of exon and intron junction regions, and examination of a 20 bp region of adjacent introns. Flanking sequences are defined as ±50 bp upstream and downstream of the 5' and 3' ends of the coding region.The raw sequence data were compared to the known gene sequence data in publicly available sequence data bases using Burrows-Wheeler Aligner software (BWA, 0.7.12-r1039), and the pathogenic variant sites were annotated using Annovar. Subsequently, the suspected pathogenic variants were classified according to ACMG's gene variation classification system. Simultaneously, unreported or clinically ambiguous pathogenic variants were predicted and annotated based on population databases. Any suspected pathogenic variants identified through this analysis were then validated using Sanger sequencing technology. At last, the proband and her affected sister carried pathogenic homozygous variant in the geneSLC34A3(exon 13, c.1402C > T; p.R468W). Their parents were both heterozygous carriers of the variant. Genetic testing revealed that the patient has anLRP5(exon 18, c.3917C > T; p.A1306V) variant of Uncertain significance, which is a rare homozygous variant. CONCLUSION This case report aims to raise awareness of the presenting characteristics of HHRH. The paper describes a unique case involving variants in both theSLC34A3andLRP5genes, which are inherited in an autosomal recessive manner. This combination of gene variants has not been previously reported in the literature. It is uncertain whether the presence of these two mutated genes in the same individual will result in more severe clinical symptoms. This report shows that an accurate diagnosis is critical, and with early diagnosis and correct treatment, patients will have a better prognosis.
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Affiliation(s)
- Lufeng Wang
- Department of Endocrinology, People's Hospital of Xinjiang Uygur Autonomous Region, Xinjiang Clinical Research Center for Diabetes, Urumqi, 830000, China
| | - Gulimire Kulaixi
- Department of Endocrinology, Yecheng County, Kashi City of Xinjiang Uygur Autonomous Region, Kashi City, 832000, China
| | - Jiazireya Zaiyinati
- Department of Endocrinology, People's Hospital of Xinjiang Uygur Autonomous Region, Xinjiang Clinical Research Center for Diabetes, Urumqi, 830000, China
| | - Guzhalikezi Aibai
- Department of Endocrinology, Yecheng County, Kashi City of Xinjiang Uygur Autonomous Region, Kashi City, 832000, China
| | - Danyang Du
- Department of Endocrinology, People's Hospital of Xinjiang Uygur Autonomous Region, Xinjiang Clinical Research Center for Diabetes, Urumqi, 830000, China
| | - Yanying Guo
- Department of Endocrinology, People's Hospital of Xinjiang Uygur Autonomous Region, Xinjiang Clinical Research Center for Diabetes, Urumqi, 830000, China.
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Dodamani MH, Memon SS, Karlekar M, Lila AR, Khan M, Sarathi V, Arya S, Jamale T, Thakare S, Patil VA, Shah NS, Bergwitz C, Bandgar TR. Hereditary Hypophosphatemic Rickets with Hypercalciuria Presenting with Enthesopathy, Renal Cysts, and High Serum c-Terminal FGF23: Single-Center Experience and Systematic Review. Calcif Tissue Int 2024; 114:137-146. [PMID: 37981601 DOI: 10.1007/s00223-023-01156-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 10/10/2023] [Indexed: 11/21/2023]
Abstract
Hereditary hypophosphatemic rickets with hypercalciuria (HHRH) is a rare disorder of phosphate homeostasis. We describe a single-center experience of genetically proven HHRH families and perform systematic review phenotype-genotype correlation in reported biallelic probands and their monoallelic relatives. Detailed clinical, biochemical, radiological, and genetic data were retrieved from our center and a systematic review of Pub-Med and Embase databases for patients and relatives who were genetically proven. Total of nine subjects (probands:5) carrying biallelic SLC34A3 mutations (novel:2) from our center had a spectrum from rickets/osteomalacia to normal BMD, with hypophosphatemia and hypercalciuria in all. We describe the first case of genetically proven HHRH with enthesopathy. Elevated FGF23 in another patient with hypophosphatemia, iron deficiency anemia, and noncirrhotic periportal fibrosis led to initial misdiagnosis as tumoral osteomalacia. On systematic review of 58 probands (with biallelic SLC34A3 mutations; 35 males), early-onset HHRH and renal calcification were present in ~ 70% and late-onset HHRH in 10%. c.575C > T p.(Ser192Leu) variant occurred in 53% of probands without skeletal involvement. Among 110 relatives harboring monoallelic SLC34A3 mutation at median age 38 years, renal calcification, hypophosphatemia, high 1,25(OH)2D, and hypercalciuria were observed in ~30%, 22.3%, 40%, and 38.8%, respectively. Renal calcifications correlated with age but were similar across truncating and non-truncating variants. Although most relatives were asymptomatic for bone involvement, 6/12(50%) had low bone mineral density. We describe the first monocentric HHRH case series from India with varied phenotypes. In a systematic review, frequent renal calcifications and low BMD in relatives with monoallelic variants (HHRH trait) merit identification.
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Affiliation(s)
- Manjunath Havalappa Dodamani
- Department of Endocrinology, Seth G.S Medical College & KEM Hospital, OPD, Parel, Mumbai, Maharashtra, 400012, India
| | - Saba Samad Memon
- Department of Endocrinology, Seth G.S Medical College & KEM Hospital, OPD, Parel, Mumbai, Maharashtra, 400012, India.
| | - Manjiri Karlekar
- Department of Endocrinology, Seth G.S Medical College & KEM Hospital, OPD, Parel, Mumbai, Maharashtra, 400012, India
| | - Anurag Ranjan Lila
- Department of Endocrinology, Seth G.S Medical College & KEM Hospital, OPD, Parel, Mumbai, Maharashtra, 400012, India
| | - Mustafa Khan
- Department of Endocrinology, Brown University, 375 Wampanoag Trail, Providence, RI, 02913, USA
- Section Endocrinology and Metabolism, Yale University School of Medicine, Anlyan Center, Office S117, Lab S110, 1 Gilbert Street, New Haven, CT, 06519, USA
| | - Vijaya Sarathi
- Department of Endocrinology, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, Karnataka, India
| | - Sneha Arya
- Department of Endocrinology, Seth G.S Medical College & KEM Hospital, OPD, Parel, Mumbai, Maharashtra, 400012, India
| | - Tukaram Jamale
- Department of Nephrology, Seth G.S Medical College & KEM Hospital, Mumbai, Maharashtra, India
| | - Sayali Thakare
- Department of Nephrology, Seth G.S Medical College & KEM Hospital, Mumbai, Maharashtra, India
| | - Virendra A Patil
- Department of Endocrinology, Seth G.S Medical College & KEM Hospital, OPD, Parel, Mumbai, Maharashtra, 400012, India
| | - Nalini S Shah
- Department of Endocrinology, Seth G.S Medical College & KEM Hospital, OPD, Parel, Mumbai, Maharashtra, 400012, India
| | - Clemens Bergwitz
- Section Endocrinology and Metabolism, Yale University School of Medicine, Anlyan Center, Office S117, Lab S110, 1 Gilbert Street, New Haven, CT, 06519, USA
| | - Tushar R Bandgar
- Department of Endocrinology, Seth G.S Medical College & KEM Hospital, OPD, Parel, Mumbai, Maharashtra, 400012, India
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Cao Y, You Y, Wang Q, Ren X, Li S, Li L, Xia W, Guan X, Yang T, Ikegawa S, Wang Z, Zhao X. Identification of six novel variants from nine Chinese families with hypophosphatemic rickets. BMC Med Genomics 2022; 15:161. [PMID: 35842615 PMCID: PMC9287957 DOI: 10.1186/s12920-022-01305-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 06/27/2022] [Indexed: 11/25/2022] Open
Abstract
Background Hypophosphatemic rickets (HR) is a rare genetic disorder associated with renal phosphate wasting and characterized by bone defects. Inactivating mutations in the phosphate regulating endopeptidase homolog X‑linked gene (PHEX) account for most cases of HR. The aim of this study was to identify causative variants in nine unrelated Chinese families associated with HR, and to determine potential pathogenicity of the identified variants. Methods Genomic DNA was isolated from the peripheral blood of HR patients and their healthy relatives, followed by next-generation sequencing and/or Sanger sequencing. In silico prediction combined with conservation analysis was performed to assess the effects of the variants, and 3D protein modeling was conducted to predict the functional effects on the encoded protein. Results All HR patients recruited in this study displayed bone deformities and tooth agenesis, as well as reduced serum phosphate levels and elevated urine phosphate levels. Nine PHEX variants were identified in eight families, including four novel variants (c.1661_1726del, c.980A > G, c.1078A > T, and c.1017_1051dup). Of the nine identified PHEX variants, five caused a truncated protein, two caused an altered amino acid, and the other two were the canonical splicing variants. Novel variants c.1336G > A and c.1364 T > C in SLC34A3 were also found in one family. Conservation analysis showed that all the amino acids corresponding to the missense variants were highly conserved. In silico analysis and 3D protein structure modeling confirmed the pathogenicity of these variants. Conclusions This study identified four novel variants in PHEX and two novel variants in SLC34A3 in a Chinese cohort with HR. Our findings highlight the dominant role of PHEX in HR, and expand the genotypic and phenotypic spectra of this disorder. Supplementary Information The online version contains supplementary material available at 10.1186/s12920-022-01305-w.
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Affiliation(s)
- Yixuan Cao
- Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Yi You
- Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Qiong Wang
- Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Xiuzhi Ren
- The People's Hospital of Wuqing District, Tianjin, 301700, China
| | - Shan Li
- Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Lulu Li
- Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Weibo Xia
- Department of Endocrinology, Key Laboratory of Endocrinology of the Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, 100730, China
| | - Xin Guan
- Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Tao Yang
- Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China
| | - Shiro Ikegawa
- Laboratory for Bone and Joint Diseases, RIKEN Center for Integrative Medical Sciences (IMS), Tokyo, 108-8639, Japan
| | - Zheng Wang
- Laboratory for Bone and Joint Diseases, RIKEN Center for Integrative Medical Sciences (IMS), Tokyo, 108-8639, Japan
| | - Xiuli Zhao
- Department of Medical Genetics, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and School of Basic Medicine, Peking Union Medical College, Beijing, 100005, China.
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Bertholet-Thomas A, Portefaix A, Flammier S, Dhelens C, Subtil F, Dubourg L, Laudy V, Le Bouar M, Boussaha I, Ndiaye M, Molin A, Lemoine S, Bacchetta J. Fluconazole in hypercalciuric patients with increased 1,25(OH) 2D levels: the prospective, randomized, placebo-controlled, double-blind FLUCOLITH trial. Trials 2022; 23:499. [PMID: 35710560 PMCID: PMC9204961 DOI: 10.1186/s13063-022-06302-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Accepted: 04/13/2022] [Indexed: 11/23/2022] Open
Abstract
Background Hypercalciuria is one of the most frequent metabolic disorders associated with nephrolithiasis and/or nephrocalcinosis possibly leading to chronic kidney disease (CKD) and bone complications in adults. Orphan diseases with different underlying primary pathophysiology share inappropriately increased 1,25(OH)2D levels and hypercalciuria, e.g., hypersensitivity to vitamin D and renal phosphate wasting. Their management is challenging, typically based on hyperhydration and dietary advice. The antifungal azoles are known to inhibit the 1α-hydroxylase and therefore decrease 1,25(OH)2D levels; they are commonly used, with well described pharmacokinetic and tolerability data. Fluconazole has been successfully reported to reduce calciuria in patients with CYP24A1 or SLC34A3 mutations, with no safety warnings. Thus, based on these case reports, we hypothesize that fluconazole is effective to decrease and normalize calciuria in patients with hypercalciuria and increased 1,25(OH)2D levels. Methods The FLUCOLITH trial is a prospective, interventional, randomized in parallel groups (1:1), placebo-controlled, double-blind trial. A total of 60 patients (10–60 years) with nephrolithiasis and/or nephrocalcinosis history, hypercalciuria (> 0.1 mmol/kg/day), increased 1,25(OH)2D levels (> 150 pmol/L), and 25-OH-D levels >20 nmol/L will be included. Inclusions will be performed only from mid-September to the beginning of February to avoid bias due to sunlight-induced vitamin D synthesis. The primary endpoint will be the proportion of patients with normalization of 24-h calciuria between baseline and 16 weeks, or with a relative decrease of at least 30% of 24-h calciuria in patients who still display at W16 a 24-h hypercalciuria. Discussion The current challenge is to propose an efficient treatment to patients with hypercalciuria and increased 1,25(OH)2D levels in order to prevent later complications and notably CKD that can ultimately lead to end-stage renal disease. Based on improvement of knowledge in phosphate/calcium metabolism, pathophysiology and genetics, the “off-label” use of fluconazole was recently reported to be useful in hypercalciuric patients with increased 1,25(OH)2D levels. Thus, the FLUCOLITH study is a unique opportunity to develop a new indication of a well-known and not expensive drug in orphan renal diseases, the ultimate objective being the secondary prevention of CKD worsening in these patients. Trial registration ClinicalTrials.gov NCT04495608. Registered on July 23, 2020. Supplementary Information The online version contains supplementary material available at 10.1186/s13063-022-06302-z.
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Affiliation(s)
- Aurélia Bertholet-Thomas
- Centre de Référence des Maladies Rénales Rares, filières maladies rares ORKID and ERK-Net, Service de Néphrologie, Rhumatologie et Dermatologie Pédiatriques, Hôpital Femme Mère Enfant, Boulevard Pinel, 69677, Bron, Cedex, France.,Centre de Référence des Maladies Rares du Calcium et du Phosphate, filière maladies rares OSCAR, Hôpital Femme Mère Enfant, Bron, France.,INSERM 1033, Prévention des Maladies Osseuses, Lyon, France
| | - Aurélie Portefaix
- Centre d'Investigation Clinique, Hôpital Cardiovasculaire Louis Pradel, Inserm 1407, 69500, Bron, France
| | - Sacha Flammier
- Centre de Référence des Maladies Rénales Rares, filières maladies rares ORKID and ERK-Net, Service de Néphrologie, Rhumatologie et Dermatologie Pédiatriques, Hôpital Femme Mère Enfant, Boulevard Pinel, 69677, Bron, Cedex, France.,Centre de Référence des Maladies Rares du Calcium et du Phosphate, filière maladies rares OSCAR, Hôpital Femme Mère Enfant, Bron, France
| | - Carole Dhelens
- Pharmacie, FRIPHARM, Hôpital Edouard Herriot, Lyon, France
| | - Fabien Subtil
- Service de Biostatistique, Hospices Civils de Lyon, Lyon, France.,Université de Lyon, Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Évolutive UMR 5558, Villeurbanne, France
| | - Laurence Dubourg
- Néphrologie, Dialyse, Hypertension Artérielle et Exploration Fonctionnelle Rénale, Hôpital Edouard Herriot, Lyon, France.,Faculté de Médecine Lyon Est, Université Lyon 1, Lyon, France
| | - Valérie Laudy
- Centre d'Investigation Clinique, Hôpital Cardiovasculaire Louis Pradel, Inserm 1407, 69500, Bron, France
| | - Myrtille Le Bouar
- Centre d'Investigation Clinique, Hôpital Cardiovasculaire Louis Pradel, Inserm 1407, 69500, Bron, France
| | - Inesse Boussaha
- Centre d'Investigation Clinique, Hôpital Cardiovasculaire Louis Pradel, Inserm 1407, 69500, Bron, France
| | - Marietou Ndiaye
- Centre d'Investigation Clinique, Hôpital Cardiovasculaire Louis Pradel, Inserm 1407, 69500, Bron, France
| | - Arnaud Molin
- Service de Génétique, CHU de Caen, Caen, France.,Centre de Référence des Maladies Rares du Calcium et du Phosphate, filière maladies rares OSCAR Caen, Caen, France
| | - Sandrine Lemoine
- Centre de Référence des Maladies Rénales Rares, filières maladies rares ORKID and ERK-Net, Service de Néphrologie, Rhumatologie et Dermatologie Pédiatriques, Hôpital Femme Mère Enfant, Boulevard Pinel, 69677, Bron, Cedex, France.,Centre de Référence des Maladies Rares du Calcium et du Phosphate, filière maladies rares OSCAR, Hôpital Femme Mère Enfant, Bron, France.,Néphrologie, Dialyse, Hypertension Artérielle et Exploration Fonctionnelle Rénale, Hôpital Edouard Herriot, Lyon, France.,Faculté de Médecine Lyon Est, Université Lyon 1, Lyon, France
| | - Justine Bacchetta
- Centre de Référence des Maladies Rénales Rares, filières maladies rares ORKID and ERK-Net, Service de Néphrologie, Rhumatologie et Dermatologie Pédiatriques, Hôpital Femme Mère Enfant, Boulevard Pinel, 69677, Bron, Cedex, France. .,Centre de Référence des Maladies Rares du Calcium et du Phosphate, filière maladies rares OSCAR, Hôpital Femme Mère Enfant, Bron, France. .,INSERM 1033, Prévention des Maladies Osseuses, Lyon, France. .,Faculté de Médecine Lyon Est, Université Lyon 1, Lyon, France.
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Turan I, Erdem S, Kotan LD, Ozdemir Dilek S, Tastan M, Gurbuz F, Bişgin A, Karabay Bayazıt A, Topaloglu AK, Yuksel B. Experience with the targeted next-generation sequencing in the diagnosis of hereditary hypophosphatemic rickets. J Pediatr Endocrinol Metab 2021; 34:639-648. [PMID: 33852231 DOI: 10.1515/jpem-2020-0624] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 02/02/2021] [Indexed: 11/15/2022]
Abstract
OBJECTIVES Hereditary Hypophosphatemic Rickets (HHR) is a heterogeneous group of disorders characterized by hypophosphatemia. Although the X-linked dominant HHR is the most common form, the genetic etiology of HHR is variable. Recently, developed next-generation sequencing techniques may provide opportunities for making HHR diagnosis in a timely and efficient way. METHODS We investigated clinical and genetic features for 18 consecutive probands and their 17 affected family members with HHR. All patient's clinical and biochemical data were collected. We first analyzed a single gene with Next-generation sequencing if the patients have a strong clue for an individual gene. For the remaining cases, a Hypophosphatemic Rickets gene panel, including all known HHR genes by Next-generation sequencing, was employed. RESULTS We were able to diagnosis all of the consecutive 35 patients in our tertiary care center. We detected nine novel and 10 previously described variants in PHEX (9; 50%), SLC34A3 (3; 17%), ENPP1 (3; 17%), SLC34A1 (1; 5%), CLCN5 (1; 5%), and DMP1 (1; 5%). CONCLUSIONS To delineate the etiology of HHR cases in a cost and time-efficient manner, we propose single gene analysis by next-generation sequencing if findings of patients indicate a strong clue for an individual gene. If that analysis is negative or for all other cases, a Next-generation Sequence gene panel, which includes all known HHR genes, should be employed.
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Affiliation(s)
- Ihsan Turan
- Department of Pediatrics, Division of Pediatric Endocrinology, Cukurova University Faculty of Medicine, Adana, Turkey
| | - Sevcan Erdem
- Department of Pediatrics, Division of Pediatric Cardiology, Cukurova University Faculty of Medicine, Adana, Turkey
| | - Leman Damla Kotan
- Department of Pediatrics, Division of Pediatric Endocrinology, Cukurova University Faculty of Medicine, Adana, Turkey
| | - Semine Ozdemir Dilek
- Department of Pediatrics, Division of Pediatric Endocrinology, Cukurova University Faculty of Medicine, Adana, Turkey
| | - Mehmet Tastan
- Department of Pediatrics, Division of Pediatric Endocrinology, Cukurova University Faculty of Medicine, Adana, Turkey
| | - Fatih Gurbuz
- Department of Pediatrics, Division of Pediatric Endocrinology, Cukurova University Faculty of Medicine, Adana, Turkey
| | - Atıl Bişgin
- AGENTEM (Adana Genetic Diseases Diagnosis and Treatment Center), Cukurova University, Adana, Turkey.,and Department of Medical Genetics, Cukurova University Faculty of Medicine, Adana, Turkey
| | - Aysun Karabay Bayazıt
- Department of Pediatrics, Division of Pediatric Nephrology, Cukurova University Faculty of Medicine, Adana, Turkey
| | - Ali Kemal Topaloglu
- Department of Pediatrics, Division of Pediatric Endocrinology, University of Mississippi Medical Center, Jackson, MS, USA
| | - Bilgin Yuksel
- Department of Pediatrics, Division of Pediatric Endocrinology, Cukurova University Faculty of Medicine, Adana, Turkey
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7
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Jiang Y, Li X, Feng J, Li M, Wang O, Xing XP, Xia WB. The genetic polymorphisms of XPR1 and SCL34A3 are associated with Fanconi syndrome in Chinese patients of tumor-induced osteomalacia. J Endocrinol Invest 2021; 44:773-780. [PMID: 32725396 DOI: 10.1007/s40618-020-01371-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 07/20/2020] [Indexed: 12/14/2022]
Abstract
PURPOSE Tumor-induced osteomalacia (TIO) is an acquired form of hypophosphatemia caused by tumors with excess production of fibroblast growth factor 23 (FGF23). Some reports showed that TIO patients had renal Fanconi syndrome (FS) with unidentified mechanism. In this study, we investigated the association between genetic polymorphisms of phosphate transporters in renal proximal tubules and TIO with FS. METHODS We recruited 30 TIO patients with FS (TIO-FS) as well as 30 TIO patients (TIO-nonFS) without any urine abnormalities matched by age and gender. We collected clinical manifestations and conducted targeted sequencing of SLC34A1, SLC34A3 and XPR1 genes and the association analysis between variants in TIO with FS and phenotypes. RESULTS TIO-FS group had lower levels of serum phosphate (0.44 ± 0.12 vs. 0.51 ± 0.07 mmol/L, p < 0.05) than TIO-nonFS group. Among the 16 SNPs in SLC34A1, SLC34A3 and XPR1 genes, GG/GC genotypes of rs148196667 in XPR1 and AA/TA genotypes of rs35535797 in SLC34A3 were associated with a reduced susceptibility to have FS. The G allele of rs148196667 in XPR1 decreased the risk of FS. The GGAA haplotype in SLC34A3 and GCT haplotype in XPR1 were associated with a decreased risk for FS. CONCLUSIONS The polymorphisms of XPR1 and SCL34A3 are associated with TIO patients with Fanconi syndrome. It provides novel insight to the relationship of phosphate transportation and general functions of renal proximal tubules.
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Affiliation(s)
- Y Jiang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing, 100730, China.
| | - X Li
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing, 100730, China
| | - J Feng
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing, 100730, China
- Department of Endocrinology and Metabolism, South Campus, Renji Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, 201112, China
| | - M Li
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing, 100730, China
| | - O Wang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing, 100730, China
| | - X-P Xing
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing, 100730, China
| | - W-B Xia
- Department of Endocrinology, Key Laboratory of Endocrinology, National Health Commission, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing, 100730, China.
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8
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Dreimane D, Chen A, Bergwitz C. Description of a novel SLC34A3.c.671delT mutation causing hereditary hypophosphatemic rickets with hypercalciuria in two adolescent boys and response to recombinant human growth hormone. Ther Adv Musculoskelet Dis 2020; 12:1759720X20912862. [PMID: 32963591 PMCID: PMC7488884 DOI: 10.1177/1759720x20912862] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 02/05/2020] [Indexed: 11/17/2022] Open
Abstract
Hereditary hypophosphatemic rickets with hypercalciuria (HHRH) is an autosomal recessive disorder characterized by hypophosphatemia, rickets, hyperphosphaturia, elevated 1,25(OH)2D, and hypercalciuria. Mutations in SLC34A3, the gene encoding the sodium-dependent cotransporter NPT2c, have previously been described as a cause of HHRH. Here, we describe two male siblings with rickets and hypercalciuric nephrolithiasis born to unrelated parents, and their response to oral phosphate supplementation and growth hormone therapy. Whole exome sequencing of the oldest brother, and polymerase chain reaction and Sanger sequence analysis of the identified SLC34A3 mutations, was performed for confirmation and to evaluate his siblings and parents. Serum and urine biochemical parameters of mineral homeostasis before and after therapy were evaluated. Whole exome sequencing analysis identified a previously reported heterozygous deletion SLC34A3.g.2259-2359del101bp on the maternal allele, and a novel heterozygous single nucleotide deletion SLC34A3.c.671delT on the paternal allele of the two affected brothers. The parents and the unaffected brother are heterozygous carriers. Recombinant human growth hormone (rHGH) plus oral phosphate in one affected brother improved the renal phosphate leak and resulted in accelerated linear growth superior to that seen with oral phosphate supplementation alone in the other affected brother. Our case study is the first to demonstrate that rHGH can be considered in addition to oral supplementation with phosphorus to improve linear growth in patients with this disorder, and suggests that renal phosphate reabsorption in response to rHGH is NPT2c-independent.
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Affiliation(s)
- Daina Dreimane
- Department of Pediatrics, Division of Endocrinology and Diabetes, School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, USA
| | - Alyssa Chen
- Department of Medicine, Section Endocrinology, Yale University School of Medicine, New Haven, CT, USA
| | - Clemens Bergwitz
- Department of Medicine, Section Endocrinology, Yale University School of Medicine, 1 Gilbert Street, New Haven, CT 06519, USA
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9
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Yu S, Chen WX, Lu W, Chen C, Ni Y, Duan B, Wang B, Wang H, Xu ZM. Novel heterozygous GATA3 and SLC34A3 variants in a 6-year-old boy with Barakat syndrome and hypercalciuria. Mol Genet Genomic Med 2020; 8:e1222. [PMID: 32155322 PMCID: PMC7216807 DOI: 10.1002/mgg3.1222] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/19/2020] [Accepted: 02/24/2020] [Indexed: 01/14/2023] Open
Abstract
Background Barakat syndrome is an autosomal dominant disorder characterized by the triad of hypoparathyroidism, sensorineural deafness, and renal anomalies and is caused by mutations in GATA3 gene. SLC34A3 is the cause gene of hypophosphatemic rickets with hypercalciuria, and heterozygous carriers may have milder clinical symptoms. The aim of this study was to identify the underlying genetic cause of a patient who initially presented with renal failure, hypercalciuria, kidney stone, and bilateral sensorineural deafness. Methods A 6‐year‐old boy with complex clinical presentations was investigated. Comprehensive medical evaluations were performed including auditory function tests, endocrine function tests, metabolic studies, and imaging examinations. Molecular diagnoses were analyzed by trio whole‐exome sequencing. Results One novel de novo deleterious variant (c. 324del) of the GATA3 gene was identified in the patient. The patient can be diagnosed with Barakat syndrome. In addition, one novel variant (c. 589A>G) of the SLC34A3 gene was detected, which was inherited from the father. This heterozygous variant can explain the hypercalciuria and kidney stone that occurred in both the patient and his father. Conclusion This study provides a special case which is phenotype‐driven dual diagnoses, and the two novel variants can parsimoniously explain the complex clinical presentations of this patient.
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Affiliation(s)
- Sha Yu
- Department of Otolaryngology-Head and Neck Surgery, Children's Hospital of Fudan University, Shanghai, China.,Center for Molecular Medicine, Pediatrics Research Institute, Children's Hospital of Fudan University, Shanghai, China
| | - Wen-Xia Chen
- Department of Otolaryngology-Head and Neck Surgery, Children's Hospital of Fudan University, Shanghai, China
| | - Wei Lu
- Endocrinology and Inherited Metabolic Diseases, Children's Hospital of Fudan University, Shanghai, China
| | - Chao Chen
- Department of Otolaryngology-Head and Neck Surgery, Children's Hospital of Fudan University, Shanghai, China
| | - Yihua Ni
- Department of Otolaryngology-Head and Neck Surgery, Children's Hospital of Fudan University, Shanghai, China
| | - Bo Duan
- Department of Otolaryngology-Head and Neck Surgery, Children's Hospital of Fudan University, Shanghai, China
| | - Bin Wang
- Department of Otolaryngology-Head and Neck Surgery, Children's Hospital of Fudan University, Shanghai, China
| | - Huijun Wang
- Center for Molecular Medicine, Pediatrics Research Institute, Children's Hospital of Fudan University, Shanghai, China
| | - Zheng-Min Xu
- Department of Otolaryngology-Head and Neck Surgery, Children's Hospital of Fudan University, Shanghai, China
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10
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Wagner CA, Rubio-Aliaga I, Hernando N. Renal phosphate handling and inherited disorders of phosphate reabsorption: an update. Pediatr Nephrol 2019; 34:549-559. [PMID: 29275531 DOI: 10.1007/s00467-017-3873-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 12/08/2017] [Accepted: 12/12/2017] [Indexed: 01/12/2023]
Abstract
Renal phosphate handling critically determines plasma phosphate and whole body phosphate levels. Filtered phosphate is mostly reabsorbed by Na+-dependent phosphate transporters located in the brush border membrane of the proximal tubule: NaPi-IIa (SLC34A1), NaPi-IIc (SLC34A3), and Pit-2 (SLC20A2). Here we review new evidence for the role and relevance of these transporters in inherited disorders of renal phosphate handling. The importance of NaPi-IIa and NaPi-IIc for renal phosphate reabsorption and mineral homeostasis has been highlighted by the identification of mutations in these transporters in a subset of patients with infantile idiopathic hypercalcemia and patients with hereditary hypophosphatemic rickets with hypercalciuria. Both diseases are characterized by disturbed calcium homeostasis secondary to elevated 1,25-(OH)2 vitamin D3 as a consequence of hypophosphatemia. In vitro analysis of mutated NaPi-IIa or NaPi-IIc transporters suggests defective trafficking underlying disease in most cases. Monoallelic pathogenic mutations in both SLC34A1 and SLC34A3 appear to be very frequent in the general population and have been associated with kidney stones. Consistent with these findings, results from genome-wide association studies indicate that variants in SLC34A1 are associated with a higher risk to develop kidney stones and chronic kidney disease, but underlying mechanisms have not been addressed to date.
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Affiliation(s)
- Carsten A Wagner
- Institute of Physiology, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland. .,National Center for Competence in Research (NCCR) Kidney.CH, Zurich, Switzerland.
| | - Isabel Rubio-Aliaga
- Institute of Physiology, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.,National Center for Competence in Research (NCCR) Kidney.CH, Zurich, Switzerland
| | - Nati Hernando
- Institute of Physiology, University of Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.,National Center for Competence in Research (NCCR) Kidney.CH, Zurich, Switzerland
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11
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Schönauer R, Petzold F, Lucinescu W, Seidel A, Müller L, Neuber S, Bergmann C, Sayer JA, Werner A, Halbritter J. Evaluating pathogenicity of SLC34A3-Ser192Leu, a frequent European missense variant in disorders of renal phosphate wasting. Urolithiasis 2019; 47:511-9. [PMID: 30798342 DOI: 10.1007/s00240-019-01116-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 02/07/2019] [Indexed: 11/26/2022]
Abstract
Loss-of-function mutations of SLC34A3 represent an established cause of a distinct renal phosphate wasting disorder termed hereditary hypophosphatemic rickets with hypercalciuria (HHRH). SLC34A3 encodes the renal phosphate transporter NaPi2c expressed at the apical brush border of proximal renal tubules. Substitution of p.Ser192Leu is one of the most frequent genetic changes among HHRH patients in Europe, but has never been systematically evaluated, clinically or on a cellular level. Identification of a 32-year-old female with a homozgyous c.575C>T, p.Ser192Leu substitution enabled a more comprehensive assessment of the impact of this missense variant. Clinically, the patient showed renal phosphate wasting and nephrocalcinosis without any bone abnormalities. Heterozygous carriers of deleterious SLC34A3 variants were previously described to harbor an increased risk of kidney stone formation and renal calcification. We hence examined the frequency of p.Ser192Leu variants in our adult kidney stone cohort and compared the results to clinical findings of previously published cases of both mono- and biallelic p.Ser192Leu changes. On a cellular level, p.Ser192Leu-mutated transporters localize to the plasma membrane in different cellular systems, but lead to significantly reduced transport activity of inorganic phosphate upon overexpression in Xenopus oocytes. Despite the reduced function in ectopic cellular systems, the clinical consequences of p.Ser192Leu may appear relatively mild, at least in our index patient, and can potentially be missed in clinical practice.
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12
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Bergwitz C, Miyamoto KI. Hereditary hypophosphatemic rickets with hypercalciuria: pathophysiology, clinical presentation, diagnosis and therapy. Pflugers Arch 2018; 471:149-163. [PMID: 30109410 DOI: 10.1007/s00424-018-2184-2] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Revised: 07/06/2018] [Accepted: 07/10/2018] [Indexed: 12/24/2022]
Abstract
Hereditary hypophosphatemic rickets with hypercalciuria (HHRH; OMIM: 241530) is a rare autosomal recessive disorder with an estimated prevalence of 1:250,000 that was originally described by Tieder et al. Individuals with HHRH carry compound-heterozygous or homozygous (comp/hom) loss-of-function mutations in the sodium-phosphate co-transporter NPT2c. These mutations result in the development of urinary phosphate (Pi) wasting and hypophosphatemic rickets, bowing, and short stature, as well as appropriately elevated 1,25(OH)2D levels, which sets this fibroblast growth factor 23 (FGF23)-independent disorder apart from the more common X-linked hypophosphatemia. The elevated 1,25(OH)2D levels in turn result in hypercalciuria due to enhanced intestinal calcium absorption and reduced parathyroid hormone (PTH)-dependent calcium-reabsorption in the distal renal tubules, leading to the development of kidney stones and/or nephrocalcinosis in approximately half of the individuals with HHRH. Even heterozygous NPT2c mutations are frequently associated with isolated hypercalciuria (IH), which increases the risk of kidney stones or nephrocalcinosis threefold in affected individuals compared with the general population. Bone disease is generally absent in individuals with IH, in contrast to those with HHRH. Treatment of HHRH and IH consists of monotherapy with oral Pi supplements, while active vitamin D analogs are contraindicated, mainly because the endogenous 1,25(OH)2D levels are already elevated but also to prevent further worsening of the hypercalciuria. Long-term studies to determine whether oral Pi supplementation alone is sufficient to prevent renal calcifications and bone loss, however, are lacking. It is also unknown how therapy should be monitored, whether secondary hyperparathyroidism can develop, and whether Pi requirements decrease with age, as observed in some FGF23-dependent hypophosphatemic disorders, or whether this can lead to osteoporosis.
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Affiliation(s)
- Clemens Bergwitz
- Section Endocrinology and Metabolism, Yale University School of Medicine, Anlyan Center, Office S117, Lab S110, 1 Gilbert Street, New Haven, CT 06519, USA.
| | - Ken-Ichi Miyamoto
- Department of Molecular Nutrition, Tokushima University Graduate School of Biomedical Sciences, Tokushima, Japan
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13
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Dhir G, Li D, Hakonarson H, Levine MA. Late-onset hereditary hypophosphatemic rickets with hypercalciuria (HHRH) due to mutation of SLC34A3/NPT2c. Bone 2017; 97:15-19. [PMID: 27939817 PMCID: PMC5367968 DOI: 10.1016/j.bone.2016.12.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 12/01/2016] [Accepted: 12/05/2016] [Indexed: 12/19/2022]
Abstract
OBJECTIVE To identify a genetic basis for markedly reduced bone density and multiple fractures in an adult patient with hypophosphatemia and hypercalciuria. SUBJECTS A 54-year-old Vietnamese man, his unaffected two daughters and wife. METHODS We performed biochemical studies and sequenced the SLC34A3 gene using genomic DNA from peripheral blood mononuclear cells. RESULTS Biochemical evaluation of the proband revealed hypophosphatemia with increased renal phosphate wasting, hypercalciuria, low serum parathyroid hormone (PTH) and an elevated serum 1,25(OH)2D level. Mutation analysis of SLC34A3 gene revealed that the patient was a compound heterozygote for two nonsynonymous nucleotide substitutions: a novel c.571G>A (p.G191S) damaging mutation and the previously reported c.200G>A (p.R67H) polymorphism, consistent with the clinical diagnosis of late-onset hereditary hypophosphatemic rickets with hypercalciuria (HHRH). His wife and older daughter both carried the p.R67H polymorphism, while his younger daughter was compound heterozygous for p.R67H and p.G191S. CONCLUSIONS HHRH is an uncommon autosomal recessive disease that generally manifests in childhood as rickets or nephrolithiasis, but an adult onset phenotype may occur in heterozygous carriers of SLC34A3 mutations. The severe presentation of this proband in adulthood with marked nephrolithiasis, multiple fractures and low bone density emphasizes the importance of measuring the serum phosphorus level in patients with suspected but unexplained osteoporosis and/or recurrent renal stones. The recognition of late-onset HHRH facilitates timely institution of appropriate therapy.
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Affiliation(s)
- Gauri Dhir
- Division of Endocrinology Diabetes and Metabolism, Cooper Medical School of Rowan University, Camden, NJ 08103, USA
| | - Dong Li
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Hakon Hakonarson
- Center for Applied Genomics, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA; Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
| | - Michael A Levine
- Department of Pediatrics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA; Division of Endocrinology and Diabetes, The Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
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14
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Chi Y, Zhao Z, He X, Sun Y, Jiang Y, Li M, Wang O, Xing X, Sun AY, Zhou X, Meng X, Xia W. A compound heterozygous mutation in SLC34A3 causes hereditary hypophosphatemic rickets with hypercalciuria in a Chinese patient. Bone 2014; 59:114-21. [PMID: 24246249 DOI: 10.1016/j.bone.2013.11.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Revised: 11/04/2013] [Accepted: 11/10/2013] [Indexed: 01/11/2023]
Abstract
Hereditary hypophosphatemic rickets with hypercalciuria (HHRH) is a rare metabolic disorder inherited in an autosomal recessive fashion and characterized by hypophosphatemia, short stature, rickets and/or osteomalacia, and secondary absorptive hypercalciuria. HHRH was recently mapped to chromosome 9q34, which contains the gene SLC34A3 which encodes the renal proximal tubular sodium-phosphate cotransporter NaPi-IIc. Here we describe a 29-year-old man with a history of childhood rickets who presented with increased renal phosphate clearance leading to hypophosphatemia, hypercalciuria, low serum parathyroid hormone (PTH), elevated serum 1,25-dihydroxyvitamin D (1,25(OH)2D) and recurrent nephrolithiasis. We performed a mutation analysis of SLC34A3 (exons and adjacent introns) of the proband and his parents to determine if there was a genetic contribution. The proband proved to be compound heterozygous for two missense mutations in SLC34A3: one novel mutation in exon 7 c.571G>C (p.G191R) and one previously identified mutation in exon 13 c.1402C>T (p.R468W). His parents were both asymptomatic heterozygous carriers of one of these two mutations. We also performed an oral phosphate loading test and compared serum phosphate, intact PTH, and intact fibroblast growth factor 23 (iFGF23) in this patient versus patients with other forms of hypophosphatemic rickets, the results of which further revealed that the mechanism of hypophosphatemia in HHRH is independent of FGF23. This is the first report of HHRH in the Chinese population. Our findings of the novel mutation in exon 7 add to the list of more than 20 reported mutations of SLC34A3.
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Affiliation(s)
- Yue Chi
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China
| | - Zhen Zhao
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China
| | - Xiaodong He
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China
| | - Yue Sun
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China
| | - Yan Jiang
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China
| | - Mei Li
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China
| | - Ou Wang
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China
| | - Xiaoping Xing
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China
| | | | - Xueying Zhou
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China
| | - Xunwu Meng
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China
| | - Weibo Xia
- Department of Endocrinology, Key Laboratory of Endocrinology, Ministry of Health, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Shuaifuyuan No. 1, Wangfujing, Dongcheng District, Beijing 100730, China.
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