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Arcidiacono GP, Camozzi V, Zaninotto M, Tripepi G, Fusaro M, Torres MO, Zanchetta F, Cannito M, Cecchinato A, Diogo M, Peleg Falb M, Plebani M, Simioni P, Sella S, Giannini S. Tubular phosphate transport: a comparison between different methods of urine sample collection in FGF23-dependent hypophosphatemic syndromes. Clin Chem Lab Med 2024; 62:1126-1132. [PMID: 38295343 DOI: 10.1515/cclm-2023-1292] [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] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 01/23/2024] [Indexed: 02/02/2024]
Abstract
OBJECTIVES Tubular maximum phosphate reabsorption per glomerular filtration rate (TmP/GFR) is used to evaluate renal phosphate reabsorption and it is a useful tool for the differential diagnosis of hypophosphatemic syndromes. TmP/GFR is typically calculated from fasting plasma and second morning void urine samples, obtained 2 h after the first void (TmP/GFR 2 h). The purpose of this study was to evaluate if TmP/GFR calculated from 24 h urine collection (TmP/GFR 24 h) can be used as an alternative for TmP/GFR 2 h in patients with urine phosphate wasting. METHODS We enrolled adult patients with X-linked hypophosphatemia (XLH) or tumor-induced osteomalacia (TIO). All patients underwent blood and urine sample collections, to calculate TmP/GFR 24 h and TmP/GFR 2 h. RESULTS Twenty patients (17 XLH and 3 TIO), aged 24-78 years, were included. All patients had low TmP/GFR 2 h (0.35 mmol/L, IQR 0.24-0.47 mmol/L) and TmP/GFR 24 h (0.31 mmol/L, IQR 0.22-0.43 mmol/L). The concordance correlation coefficient between TmP/GFR 2 h and TmP/GFR 24 h was 0.86 (95 % CI: 0.69-0.93), with a systematic bias of 0.05 mmol/L (95 % limits of agreement: -0.10 to 0.20). Furthermore, in 70 % (i.e., 14 patients out of 20) and 80 % (i.e., 16 patients out of 20) of cases the difference between TmP/GFR 2 h and TmP/GFR 24 h was within ±30 % and ±35 %, respectively. CONCLUSIONS Despite TmP/GFR 2 and 24 h show a relatively suboptimal agreement, the difference between the two parameters appears to be small and not clinically significant in the setting of adult patients with FGF23-dependent urine phosphate wasting and secondary hypophosphatemia.
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Affiliation(s)
| | - Valentina Camozzi
- Department of Medicine, Endocrinology Unit, University of Padova, Padova, Italy
| | - Martina Zaninotto
- Department of Medicine, Laboratory Medicine Unit, University of Padova, Padova, Italy
| | - Giovanni Tripepi
- National Research Council (CNR), Institute of Clinical Physiology (IFC), Clinical Epidemiology of Renal Diseases and Hypertension, Ospedali Riuniti, Reggio Calabria, Italy
| | - Maria Fusaro
- National Research Council (CNR), Institute of Clinical Physiology (IFC), Pisa, Italy
| | | | - Francesca Zanchetta
- Department of Medicine, Clinica Medica 1, University of Padova, Padova, Italy
| | - Michele Cannito
- Department of Medicine, Endocrinology Unit, University of Padova, Padova, Italy
| | - Alberta Cecchinato
- Department of Medicine, Clinica Medica 1, University of Padova, Padova, Italy
| | - Martin Diogo
- Department of Medicine, Clinica Medica 1, University of Padova, Padova, Italy
| | - Mor Peleg Falb
- Department of Medicine, Clinica Medica 1, University of Padova, Padova, Italy
| | - Mario Plebani
- Department of Medicine, Laboratory Medicine Unit, University of Padova, Padova, Italy
| | - Paolo Simioni
- Department of Medicine, General Medicine and Thrombotic and Hemorrhagic Diseases Unit, University of Padova, Padova, Italy
| | - Stefania Sella
- Department of Medicine, Clinica Medica 1, University of Padova, Padova, Italy
| | - Sandro Giannini
- Department of Medicine, Clinica Medica 1, University of Padova, Padova, Italy
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Ito N, Hidaka N, Kato H. The pathophysiology of hypophosphatemia. Best Pract Res Clin Endocrinol Metab 2024; 38:101851. [PMID: 38087658 DOI: 10.1016/j.beem.2023.101851] [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] [Indexed: 02/27/2024]
Abstract
After identification of fibroblast growth factor (FGF) 23 as the pivotal regulator of chronic serum inorganic phosphate (Pi) levels, the etiology of disorders causing hypophosphatemic rickets/osteomalacia has been clarified, and measurement of intact FGF23 serves as a potent tool for differential diagnosis of chronic hypophosphatemia. Additionally, measurement of bone-specific alkaline phosphatase (BAP) is recommended to differentiate acute and subacute hypophosphatemia from chronic hypophosphatemia. This article divides the etiology of chronic hypophosphatemia into 4 groups: A. FGF23 related, B. primary tubular dysfunction, C. disturbance of vitamin D metabolism, and D. parathyroid hormone 1 receptor (PTH1R) mediated. Each group is further divided into its inherited form and acquired form. Topics for each group are described, including "ectopic FGF23 syndrome," "alcohol consumption-induced FGF23-related hypophosphatemia," "anti-mitochondrial antibody associated hypophosphatemia," and "vitamin D-dependent rickets type 3." Finally, a flowchart for differential diagnosis of chronic hypophosphatemia is introduced.
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Affiliation(s)
- Nobuaki Ito
- Division of Nephrology and Endocrinology, The University of Tokyo Hospital, Tokyo, Japan; Osteoporosis Center, The University of Tokyo Hospital, Tokyo, Japan.
| | - Naoko Hidaka
- Division of Nephrology and Endocrinology, The University of Tokyo Hospital, Tokyo, Japan; Osteoporosis Center, The University of Tokyo Hospital, Tokyo, Japan.
| | - Hajime Kato
- Division of Nephrology and Endocrinology, The University of Tokyo Hospital, Tokyo, Japan; Osteoporosis Center, The University of Tokyo Hospital, Tokyo, Japan.
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3
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Bosman A, Appelman-Dijkstra NM, Boot AM, de Borst MH, van de Ven AC, de Jongh RT, Bökenkamp A, van den Bergh JP, van der Eerden BCJ, Zillikens MC. Disease Manifestations and Complications in Dutch X-Linked Hypophosphatemia Patients. Calcif Tissue Int 2024; 114:255-266. [PMID: 38226986 PMCID: PMC10901935 DOI: 10.1007/s00223-023-01172-2] [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] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Accepted: 11/27/2023] [Indexed: 01/17/2024]
Abstract
X-linked hypophosphatemia (XLH) is the most common monogenetic cause of chronic hypophosphatemia, characterized by rickets and osteomalacia. Disease manifestations and treatment of XLH patients in the Netherlands are currently unknown. Characteristics of XLH patients participating in the Dutch observational registry for genetic hypophosphatemia and acquired renal phosphate wasting were analyzed. Eighty XLH patients, including 29 children, were included. Genetic testing, performed in 78.8% of patients, showed a PHEX mutation in 96.8%. Median (range) Z-score for height was - 2.5 (- 5.5; 1.0) in adults and - 1.4 (- 3.7; 1.0) in children. Many patients were overweight or obese: 64.3% of adults and 37.0% of children. All children received XLH-related medication e.g., active vitamin D, phosphate supplementation or burosumab, while 8 adults used no medication. Lower age at start of XLH-related treatment was associated with higher height at inclusion. Hearing loss was reported in 6.9% of children and 31.4% of adults. Knee deformities were observed in 75.0% of all patients and osteoarthritis in 51.0% of adult patients. Nephrocalcinosis was observed in 62.1% of children and 33.3% of adults. Earlier start of XLH-related treatment was associated with higher risk of nephrocalcinosis and detection at younger age. Hyperparathyroidism longer than six months was reported in 37.9% of children and 35.3% of adults. This nationwide study confirms the high prevalence of adiposity, hearing loss, bone deformities, osteoarthritis, nephrocalcinosis and hyperparathyroidism in Dutch XLH patients. Early start of XLH-related treatment appears to be beneficial for longitudinal growth but may increase development of nephrocalcinosis.
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Affiliation(s)
- A Bosman
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000, CA, Rotterdam, The Netherlands
| | - N M Appelman-Dijkstra
- Department of Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - A M Boot
- Department of Pediatrics, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - M H de Borst
- Department of Internal Medicine, University Medical Center Groningen, Groningen, The Netherlands
| | - A C van de Ven
- Department of Internal Medicine, Radboud University Medical Center, Nijmegen, The Netherlands
| | - R T de Jongh
- Department of Internal Medicine, Amsterdam University Medical Center, Vrije Universiteit, Amsterdam, The Netherlands
| | - A Bökenkamp
- Department of Pediatric Nephrology, Amsterdam University Medical Center, Emma Children's Hospital, Amsterdam, The Netherlands
| | - J P van den Bergh
- Department of Internal Medicine, VieCuri Medical Center, Venlo, The Netherlands
| | - B C J van der Eerden
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000, CA, Rotterdam, The Netherlands
| | - M C Zillikens
- Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, PO Box 2040, 3000, CA, Rotterdam, The Netherlands.
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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] [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: 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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Minisola S, Colangelo L, Pepe J, Cipriani C. Skeletal Perturbations Following Sudden Stimuli. J Clin Endocrinol Metab 2024; 109:e864-e865. [PMID: 37466206 DOI: 10.1210/clinem/dgad430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Accepted: 07/17/2023] [Indexed: 07/20/2023]
Affiliation(s)
- Salvatore Minisola
- Institute of 2nd Medical Clinics, Department of Clinical, Internal, Anaesthesiologic and Cardiovascular Sciences, "Sapienza" University of Rome, 00161 Rome, Italy
| | - Luciano Colangelo
- Institute of 2nd Medical Clinics, Department of Clinical, Internal, Anaesthesiologic and Cardiovascular Sciences, "Sapienza" University of Rome, 00161 Rome, Italy
| | - Jessica Pepe
- Institute of 2nd Medical Clinics, Department of Clinical, Internal, Anaesthesiologic and Cardiovascular Sciences, "Sapienza" University of Rome, 00161 Rome, Italy
| | - Cristiana Cipriani
- Institute of 2nd Medical Clinics, Department of Clinical, Internal, Anaesthesiologic and Cardiovascular Sciences, "Sapienza" University of Rome, 00161 Rome, Italy
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Park E, Kang HG. X-linked hypophosphatemic rickets: from diagnosis to management. Clin Exp Pediatr 2024; 67:17-25. [PMID: 37321578 PMCID: PMC10764665 DOI: 10.3345/cep.2022.01459] [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] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2022] [Revised: 02/02/2023] [Accepted: 03/28/2023] [Indexed: 06/17/2023] Open
Abstract
X-linked hypophosphatemia (XLH), the most common cause of hypophosphatemic rickets, affects one in every 20,000 people. Although conventional therapy for XLH was introduced approximately 4 decades ago, the temporary replacement of oral phosphate salts and activated vitamin D cannot completely control chronic hypophosphatemia, leaving patients with incomplete healing and residual skeletal deformity as well as at risk of endocrine abnormalities and adverse drug reactions. However, understanding the pathophysiology has led to the development of a targeted therapy, burosumab, a fibroblast growth factor-23 inhibitor that was recently approved in Korea for the treatment of XLH. This review provides insight into the diagnosis, evaluation, treatment, and recommended follow-up for a typical case of XLH and reviews its pathophysiology.
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Affiliation(s)
- Eujin Park
- Department of Pediatrics, Korea University Guro Hospital, Korea University College of Medicine, Seoul, Korea
| | - Hee Gyung Kang
- Department of Pediatrics, Seoul National University College of Medicine, Seoul, Korea
- Departments of Pediatrics, Seoul National University Children’s Hospital, Seoul, Korea
- Kidney Research Institute, Medical Research Center, Seoul National University College of Medicine, Seoul, Korea
- Wide River Institute of Immunology, Seoul National University, Hongcheon, Korea
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7
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Borghi M, da Silva LM, Bispo L, Longui CA. A genetic study of a Brazilian cohort of patients with X-linked hypophosphatemia reveals no correlation between genotype and phenotype. Front Pediatr 2023; 11:1215952. [PMID: 37794959 PMCID: PMC10546205 DOI: 10.3389/fped.2023.1215952] [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] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 09/04/2023] [Indexed: 10/06/2023] Open
Abstract
Aim X-linked hypophosphatemia (XLH) is the most common inherited form of rickets, and it is caused by pathogenic inactivating variants of the phosphate-regulating endopeptidase homolog X-linked (PHEX) gene. The main purpose of this study is to identify the presence of a genotype-phenotype correlation in a cohort of XLH patients. Methods This is a retrospective study including patients diagnosed with hypophosphatemic rickets, confirmed by clinical, radiological, and laboratory findings. Medical records were reviewed for phenotypic analyses. Genomic DNA was extracted from the peripheral blood lymphocytes, and PHEX sequencing was performed by exomic NGS sequencing. The Wilcoxon rank-sum test and the two-tailed Fisher's exact test were employed for the statistical analyses of this study. Results A total of 41 patients were included in this study, and 63.41% (26/41) of the patients were female. The mutation analyses identified 29.27% missense variants and 29.72% nonsense variants, most of them were considered deleterious (66.41%). Six novel deleterious variants in the PHEX gene were detected in seven patients. The median concentrations of pretreatment serum calcium, phosphorus, and parathyroid hormone (PTH) were not significantly different among patients with different genotypes. An orthopedic surgery due to bone deformity was required in 57.69%. Conclusions Our analysis did not identify any specific genotype as a predictor. No significant genotype-phenotype correlation was found, suggesting that the recognition of subjacent pathogenic mutation in the PHEX gene may have limited prognostic value. Despite this finding, genetic testing may be useful for identifying affected individuals early and providing appropriate treatment.
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Affiliation(s)
- Mauro Borghi
- School of Medical Sciences Santa Casa SP and Pediatric Endocrinology Unit, Irmandade da Santa Casa de Misericórdia de São Paulo, São Paulo, Brazil
- Hospital São Luiz—Rede D´Or—CMA, Departament of Anesthesiology, São Paulo, Brazil
| | | | - Luciana Bispo
- Laboratório Mendelics, Department of Genetic, São Paulo, Brazil
| | - Carlos A. Longui
- School of Medical Sciences Santa Casa SP and Pediatric Endocrinology Unit, Irmandade da Santa Casa de Misericórdia de São Paulo, São Paulo, Brazil
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Ewert A, Rehberg M, Schlingmann KP, Hiort O, John-Kroegel U, Metzing O, Wühl E, Schaefer F, Kemper MJ, Derichs U, Richter-Unruh A, Patzer L, Albers N, Dunstheimer D, Haberland H, Heger S, Schröder C, Jorch N, Schmid E, Staude H, Weitz M, Freiberg C, Leifheit-Nestler M, Zivicnjak M, Schnabel D, Haffner D. Effects of Burosumab Treatment on Mineral Metabolism in Children and Adolescents With X-linked Hypophosphatemia. J Clin Endocrinol Metab 2023; 108:e998-e1006. [PMID: 37097907 DOI: 10.1210/clinem/dgad223] [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: 11/25/2022] [Revised: 04/05/2023] [Accepted: 04/13/2023] [Indexed: 04/26/2023]
Abstract
CONTEXT Burosumab has been approved for the treatment of children and adults with X-linked hypophosphatemia (XLH). Real-world data and evidence for its efficacy in adolescents are lacking. OBJECTIVE To assess the effects of 12 months of burosumab treatment on mineral metabolism in children (aged <12 years) and adolescents (aged 12-18 years) with XLH. DESIGN Prospective national registry. SETTING Hospital clinics. PATIENTS A total of 93 patients with XLH (65 children, 28 adolescents). MAIN OUTCOME MEASURES Z scores for serum phosphate, alkaline phosphatase (ALP), and renal tubular reabsorption of phosphate per glomerular filtration rate (TmP/GFR) at 12 months. RESULTS At baseline, patients showed hypophosphatemia (-4.4 SD), reduced TmP/GFR (-6.5 SD), and elevated ALP (2.7 SD, each P < .001 vs healthy children) irrespective of age, suggesting active rickets despite prior therapy with oral phosphate and active vitamin D in 88% of patients. Burosumab treatment resulted in comparable increases in serum phosphate and TmP/GFR in children and adolescents with XLH and a steady decline in serum ALP (each P < .001 vs baseline). At 12 months, serum phosphate, TmP/GFR, and ALP levels were within the age-related normal range in approximately 42%, 27%, and 80% of patients in both groups, respectively, with a lower, weight-based final burosumab dose in adolescents compared with children (0.72 vs 1.06 mg/kg, P < .01). CONCLUSIONS In this real-world setting, 12 months of burosumab treatment was equally effective in normalizing serum ALP in adolescents and children, despite persistent mild hypophosphatemia in one-half of patients, suggesting that complete normalization of serum phosphate is not mandatory for substantial improvement of rickets in these patients. Adolescents appear to require lower weight-based burosumab dosage than children.
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Affiliation(s)
- Annika Ewert
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover 30625, Germany
| | - Mirko Rehberg
- Department of Pediatrics, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne 50937, Germany
| | - Karl Peter Schlingmann
- Department of General Pediatrics, Pediatric Nephrology, University Children's Hospital, Münster 48149, Germany
| | - Olaf Hiort
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University of Lübeck, Lübeck 23562, Germany
| | | | | | - Elke Wühl
- Division of Pediatric Nephrology, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg 69120, Germany
| | - Franz Schaefer
- Division of Pediatric Nephrology, Center for Pediatric and Adolescent Medicine, University Hospital Heidelberg, Heidelberg 69120, Germany
| | - Markus J Kemper
- Asklepios Children's Hospital Hamburg-Heidberg, Hamburg-Heidberg 22417, Germany
| | - Ute Derichs
- University Children's Hospital, Mainz 55131, Germany
| | | | - Ludwig Patzer
- St. Elisabeth and St. Barbara Children's Hospital, Halle/Saale 06110, Germany
| | - Norbert Albers
- Christliches Kinderhospital Osnabrück, Osnabrück 49074, Germany
| | | | - Holger Haberland
- Children's Hospital, Sana Klinikum Lichtenberg, Berlin Lichtenberg 10365, Germany
| | - Sabine Heger
- Kinderkrankenhaus auf der Bult, Hannover 30173, Germany
| | - Carmen Schröder
- University Children's Hospital Greifswald, Greifswald 17475, Germany
| | - Norbert Jorch
- University Children's Hospital, Evangelisches Klinikum Bethel, Bielefeld 33617, Germany
| | - Elmar Schmid
- Clinic for Pediatric Nephrology Hirschaid, Hirschaid 96114, Germany
| | - Hagen Staude
- University Children's Hospital Rostock, Rostock 18057, Germany
| | - Marcus Weitz
- Department of General Pediatrics and Hematology/Oncology, University Children's Hospital, University Hospital Tübingen, Tübingen 72076, Germany
| | - Clemens Freiberg
- Department of Pediatrics and Adolescent Medicine, University Medical Center Göttingen, Göttingen 37075, Germany
| | - Maren Leifheit-Nestler
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover 30625, Germany
| | - Miroslav Zivicnjak
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover 30625, Germany
| | - Dirk Schnabel
- Center for Chronically Sick Children, Pediatric Endocrinology, University Medicine, Charité, Berlin 13353, Germany
| | - Dieter Haffner
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Hannover 30625, Germany
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Pons-Belda OD, Alonso-Álvarez MA, González-Rodríguez JD, Mantecón-Fernández L, Santos-Rodríguez F. Mineral Metabolism in Children: Interrelation between Vitamin D and FGF23. Int J Mol Sci 2023; 24:ijms24076661. [PMID: 37047636 PMCID: PMC10094813 DOI: 10.3390/ijms24076661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 03/29/2023] [Accepted: 04/01/2023] [Indexed: 04/05/2023] Open
Abstract
Fibroblast growth factor 23 (FGF23) was identified at the turn of the century as the long-sought circulating phosphatonin in human pathology. Since then, several clinical and experimental studies have investigated the metabolism of FGF23 and revealed its relevant pathogenic role in various diseases. Most of these studies have been performed in adult individuals. However, the mineral metabolism of the child is, to a large extent, different from that of the adult because, in addition to bone remodeling, the child undergoes a specific process of endochondral ossification responsible for adequate mineralization of long bones’ metaphysis and growth in height. Vitamin D metabolism is known to be deeply involved in these processes. FGF23 might have an influence on bones’ growth as well as on the high and age-dependent serum phosphate concentrations found in infancy and childhood. However, the interaction between FGF23 and vitamin D in children is largely unknown. Thus, this review focuses on the following aspects of FGF23 metabolism in the pediatric age: circulating concentrations’ reference values, as well as those of other major variables involved in mineral homeostasis, and the relationship with vitamin D metabolism in the neonatal period, in vitamin D deficiency, in chronic kidney disease (CKD) and in hypophosphatemic disorders.
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Affiliation(s)
| | | | | | | | - Fernando Santos-Rodríguez
- Hospital Universitario Central de Asturias, 33011 Oviedo, Spain
- Department of Medicine, Faculty of Medicine, University of Oviedo, 33003 Oviedo, Spain
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10
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Kamenicky P, Briot K, Brandi ML, Cohen-Solal M, Crowley RK, Keen R, Kolta S, Lachmann RH, Lecoq AL, Ralston SH, Walsh JS, Rylands AJ, Williams A, Sun W, Nixon A, Nixon M, Javaid MK. Benefit of burosumab in adults with X-linked hypophosphataemia (XLH) is maintained with long-term treatment. RMD Open 2023; 9:rmdopen-2022-002676. [PMID: 36854566 PMCID: PMC9980374 DOI: 10.1136/rmdopen-2022-002676] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [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: 08/17/2022] [Accepted: 01/02/2023] [Indexed: 03/02/2023] Open
Abstract
OBJECTIVES To report the impact of continued burosumab treatment on clinical laboratory tests of efficacy, patient-reported outcomes (PROs) and ambulatory function in adults with X-linked hypophosphataemia who continued from a 96-week phase 3 study into a 48-week open-label extension. METHODS Eligible participants from the phase 3 study continued on the burosumab regimen received at the end of the phase 3 study for a further 48 weeks (n=31). Some (not all) received compassionate burosumab treatment between the two studies (a period of 6-18 months). The primary efficacy outcome was fasting serum phosphate concentration; secondary outcomes were serum 1,25 dihydroxyvitamin D concentration, renal phosphate reabsorption, PROs and ambulatory function. RESULTS Improvements in fasting serum phosphate, serum 1,25 dihydroxyvitamin D and renal phosphate reabsorption at 96 weeks were maintained through the 48-week extension. Improvements were also maintained in stiffness and physical function measured using the Western Ontario and McMaster Universities Osteoarthritis Index, pain and fatigue endpoints measuring using the Brief Pain Inventory short-form and Brief Pain Inventory, respectively, and in ambulatory function (6-Minute Walk Test).A post-hoc exploratory analysis exploring outcomes in participants who discontinued burosumab treatment between the studies (n=7) and those who received at least one dose (n=23) indicated that the benefits of burosumab on clinical laboratory tests of efficacy, PROs and ambulatory function may be lost when treatment is interrupted but recover over time when treatment is reinstated. CONCLUSION Continued treatment with burosumab appears necessary for sustained clinical benefit. TRIAL REGISTRATION NUMBERS Phase 3: NCT02526160; open-label extension: NCT03920072.
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Affiliation(s)
- Peter Kamenicky
- Service d'Endocrinologie et des Maladies de la Reproduction, Hôpital Bicêtre, Paris, France
| | - Karine Briot
- Service de Rhumatologie, Hôpital Cochin, Paris, France
| | | | - Martine Cohen-Solal
- INSERM U1132 BIOSCAR, Service de Rhumatologie, Hôpital Lariboisiere, Université de Paris, Paris, France
| | - Rachel K Crowley
- Rare Disease Clinical Trial Network, University College Dublin School of Medicine, Dublin, Ireland.,Department of Endocrinology, St Vincent's University Hospital, Dublin, Ireland
| | - Richard Keen
- Metabolic Bone Disease Unit, Royal National Orthopaedic Hospital, Stanmore, UK
| | - Sami Kolta
- INSERM U1153, Service de Rhumatologie, Hôpital Cochin, Paris, France
| | - Robin H Lachmann
- Charles Dent Metabolic Unit, National Hospital for Neurology and Neurosurgery, London, UK
| | - Anne-Lise Lecoq
- Physiologie et Physiopathologie Endocriniennes, Assistance Publique - Hôpitaux de Paris, Paris, France.,Service d'Endocrinologie et des Maladies de la Reproduction, Hôpital Bicêtre, Paris, France
| | - Stuart H Ralston
- Medical Research Council Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Jennifer S Walsh
- Department of Oncology and Metabolism, The University of Sheffield, Sheffield, UK
| | - Angela J Rylands
- Health Economics and Outcomes Research Department, Kyowa Kirin International PLC, Marlow, UK
| | - Angela Williams
- Health Economics and Outcomes Research Department, Kyowa Kirin International PLC, Marlow, UK
| | - Wei Sun
- Biostatistics Department, Kyowa Kirin Pharmaceutical Development, Inc, Princeton, New Jersey, USA
| | | | | | - Muhammad K Javaid
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal Sciences, National Institute for Health Research Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
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11
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Shaker JL, Wermers RA. The Eucalcemic Patient With Elevated Parathyroid Hormone Levels. J Endocr Soc 2023; 7:bvad013. [PMID: 36793479 PMCID: PMC9922947 DOI: 10.1210/jendso/bvad013] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Indexed: 02/15/2023] Open
Abstract
Primary hyperparathyroidism (PHPT) is classically characterized by hypercalcemia with elevated or inappropriately normal parathyroid hormone (PTH) levels. Elevated PTH levels in the presence of normal calcium levels are not infrequently found during the evaluation of metabolic bone disorders or kidney stone disease. This can be caused by secondary hyperparathyroidism (SHPT) or normocalcemic primary hyperparathyroidism (NPHPT). NPHPT is due to autonomous parathyroid function whereas SHPT is caused by a physiologic stimulation to PTH secretion. Many medical conditions and medications can contribute to SHPT, and differentiation between SHPT and NPHPT may be difficult. Cases are presented to illustrate examples. In this paper, we review the distinction between SHPT and NPHPT as well as end organ effects of NPHPT and outcomes of surgery in NPHPT. We suggest that the diagnosis of NPHPT be made only after careful exclusion of causes of SHPT and consideration of medications that can increase PTH secretion. Further, we advise a conservative approach to surgery in NPHPT.
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Affiliation(s)
- Joseph L Shaker
- Correspondence: Joseph L. Shaker, MD, W129N7155 Northfield Dr, Menomonee Falls, WI 53051, USA.
| | - Robert A Wermers
- Department of Medicine and Division of Endocrinology, Diabetes, Metabolism and Nutrition, Mayo Clinic, Rochester, MN, USA
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12
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Abstract
Hypophosphatemic rickets typically presents in infancy or early childhood with skeletal deformities and growth plate abnormalities. The most common causes are genetic (such as X-linked hypophosphatemia), and these typically will result in lifelong hypophosphatemia and osteomalacia. Knowledge of phosphate metabolism, including the effects of fibroblast growth factor 23 (FGF23) (an osteocyte produced hormone that downregulates renal phosphate reabsorption and 1,25-dihydroxyvitamin-D (1,25(OH)2D) production), is critical to determining the underlying genetic or acquired causes of hypophosphatemia and to facilitate appropriate treatment. Serum phosphorus should be measured in any child or adult with musculoskeletal complaints suggesting rickets or osteomalacia. Clinical evaluation incudes thorough history, physical examination, laboratory investigations, genetic analysis (especially in the absence of a guiding family history), and imaging to establish etiology and to monitor severity and treatment course. The treatment depends on the underlying cause, but often includes active forms of vitamin D combined with phosphate salts, or anti-FGF23 antibody treatment (burosumab) for X-linked hypophosphatemia. The purpose of this article is to explore the approach to evaluating hypophosphatemic rickets and its treatment options.
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Affiliation(s)
- Sarah A Ackah
- Department of Medicine, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Erik A Imel
- Department of Medicine, Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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13
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Ma X, Pang Q, Zhang Q, Jiang Y, Wang O, Li M, Xing X, Xia W. A Novel Synonymous Variant of PHEX in a Patient with X-Linked Hypophosphatemia. Calcif Tissue Int 2022; 111:634-640. [PMID: 35831717 DOI: 10.1007/s00223-022-01003-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] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 06/23/2022] [Indexed: 11/29/2022]
Abstract
X-linked dominant hypophosphatemia (XLH), the most common form of hereditary hypophosphatemic rickets/osteomalacia, is caused by loss-of-function phosphate-regulating endopeptidase homolog X-linked gene (PHEX) variants. However, synonymous PHEX variants are rare in XLH. We report a 7-year-old boy with hypophosphatemia, short stature, and lower limb deformity. Whole-exome sequencing, reverse transcription-polymerase chain reaction, and Sanger sequencing were performed to identify the pathogenicity of the variant. A novel synonymous PHEX variant (NM_000444.4:c.1530 C>T, p.Arg510Arg) was detected in the proband. Further analysis revealed a 58-bp deletion at the 5' site of exon 14 during splicing. This study extends the genetic spectrum of XLH and confirms the rarity and significance of synonymous PHEX variants.
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Affiliation(s)
- Xiaosen Ma
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, People's Republic of China
| | - Qianqian Pang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, People's Republic of China
| | - Qi Zhang
- Laboratory Department, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Yan Jiang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, People's Republic of China
| | - Ou Wang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, People's Republic of China
| | - Mei Li
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, People's Republic of China
| | - Xiaoping Xing
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, People's Republic of China
| | - Weibo Xia
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, 100730, People's Republic of China.
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14
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Ni X, Liu W, Zhang D, Li X, Chi Y, Feng J, Jin C, Pang Q, Gong Y, Cui L, Jiajue R, Yu W, Wu H, Huo L, Liu Y, Jin J, Zhou X, Lv W, Zhou L, Xia Y, Wang O, Li M, Xing X, Jiang Y, Xia W. Hyperparathyroidism in a Large Cohort of Chinese Patients with Tumor-Induced Osteomalacia. J Clin Endocrinol Metab 2022; 108:1224-1235. [PMID: 36334263 DOI: 10.1210/clinem/dgac650] [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] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Revised: 11/01/2022] [Accepted: 11/01/2022] [Indexed: 11/08/2022]
Abstract
CONTEXT Tumor-induced osteomalacia (TIO) is a rare paraneoplastic syndrome caused by excessive production of fibroblast growth factor 23 (FGF23) by a tumor. Hyperparathyroidism (HPT) including secondary HPT (SHPT) and tertiary HPT (THPT) in TIO patients, which is considered to associate with phosphate supplementation, has not been well documented. OBJECTIVES To clarify the prevalence, clinical characteristics, and risk factors for HPT in a large cohort of Chinese TIO patients in our hospital. DESIGN, SETTING AND PARTICIPANTS This retrospective study enrolled 202 TIO patients. MAIN OUTCOME MEASUREMENTS Occurrence of HPT in TIO patients. RESULTS HPT was observed in 91 patients (91/202, 45.1%), as 84 patients (41.6%) were diagnosed as SHPT and seven patients (3.5%) were diagnosed as THPT. All patients with THPT underwent parathyroidectomy and only one patient experienced recurrence. Compared with patients without HPT, patients with SHPT had longer disease duration, higher rate of phosphate and calcitriol supplementation, lower serum calcium, lower urine calcium excretion, and higher urine phosphate excretion. Compared with patients with SHPT, patients with THPT had even longer disease duration, higher rate of phosphate and calcitriol supplementation. PTH levels showed positive correlation with intact FGF23 and 1,25(OH)2D levels, but not 25OHD level in TIO patients. Multivariate logistic regression analysis showed that long disease duration and phosphate supplementation were independently associated with occurrence of HPT in TIO patients. Further logistic regression analysis and restricted cubic spline model revealed dose-response relationship between cumulative dose of phosphate supplementation and PTH levels. CONCLUSIONS HPT is common in our TIO patients. To avoid the occurrence of HPT in TIO patients, timely diagnosis and tumor resection is necessary, and excessive dose of phosphate supplementation is not suggested before surgery.
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Affiliation(s)
- Xiaolin Ni
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Wei Liu
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Dingding Zhang
- Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Xiang Li
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Yue Chi
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Juan Feng
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- Department of Endocrinology and Metabolism, Renji Hospital, School of Medicine, Shanghai Jiaotong University, Shanghai, China
| | - Chenxi Jin
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- Department of Endocrinology, Beijing Tsinghua Changgung Hospital, School of Clinical Medicine, Tsinghua University, Beijing, China
| | - Qianqian Pang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Yiyi Gong
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
- Medical Research Center, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Lijia Cui
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Ruizhi Jiajue
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Wei Yu
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Huanwen Wu
- Department of Pathology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Li Huo
- Department of Nuclear Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Yong Liu
- Department of Orthopedic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Jin Jin
- Department of Orthopedic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Xi Zhou
- Department of Orthopedic Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Wei Lv
- Department of Ear, Nose, and Throat, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Lian Zhou
- Department of Stomatology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Yu Xia
- Department of Ultrasound Diagnosis, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Ou Wang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Mei Li
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Xiaoping Xing
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Yan Jiang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Weibo Xia
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
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15
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Paloian NJ, Nemeth B, Sharafinski M, Modaff P, Steiner RD. Real-world effectiveness of burosumab in children with X-linked hypophosphatemic rickets. Pediatr Nephrol 2022; 37:2667-2677. [PMID: 35211790 DOI: 10.1007/s00467-022-05484-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [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: 10/04/2021] [Revised: 01/26/2022] [Accepted: 01/27/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND X-linked hypophosphatemic rickets (XLH) is the most common cause of inherited rickets. Historically, XLH was treated with oral phosphate and calcitriol (conventional treatment). Burosumab, a fibroblast growth factor 23 (FGF-23) monoclonal antibody, was approved by the United States Food and Drug Administration (FDA) in 2018 for XLH treatment. Nevertheless, conventional treatment of XLH continues to be recommended by some specialists due to lack of published experience with burosumab in the clinical setting. We compared laboratory and radiographic changes observed following transition from conventional therapy to burosumab in pediatric XLH patients as part of routine care. METHODS This retrospective single-center study identified and retroactively studied twelve patients aged 1-18 years old with XLH previously treated with conventional therapy and transitioned to burosumab. Laboratory studies and radiographs were obtained routinely as standard of care during two treatment periods: (1) conventional therapy and (2) burosumab treatment. Laboratory values and radiologic rickets severity scores were compared between periods. RESULTS All laboratory values demonstrated improvement following 1 month of burosumab treatment, findings which were sustained over the 2-year study period. Rickets severity scores and height z-scores also improved with burosumab. There were no serious adverse events with burosumab, and adverse events overall were very infrequent and mild. One patient developed an asymptomatic mild elevation of serum phosphate while taking burosumab resulting in a temporary pause in therapy. CONCLUSIONS Safety and effectiveness of burosumab in treatment of XLH were demonstrated as burosumab yielded statistically significant improvement in laboratory and radiographic markers of rickets and height compared to conventional therapy. A higher resolution version of the Graphical abstract is available as Supplementary information.
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Affiliation(s)
- Neil J Paloian
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA.
| | - Blaise Nemeth
- Department of Orthopedics and Rehabilitation, University of Wisconsin School of Medicine and Public Health, Madison, WI, USA
| | | | - Peggy Modaff
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA
| | - Robert D Steiner
- Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, 600 Highland Ave, Madison, WI, 53792, USA
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16
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Imanishi Y, Shoji T, Emoto M. Complications and Treatments in Adult X-Linked Hypophosphatemia. Endocrines 2022; 3:560-569. [DOI: 10.3390/endocrines3030047] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
X-linked hypophosphatemia (XLH) is a rare inherited disorder involving elevated levels of fibroblast growth factor (FGF) 23, and is caused by loss-of-function mutations in the PHEX gene. FGF23 induces renal phosphate wasting and suppresses the activation of vitamin D, resulting in defective bone mineralization and rachitic changes in the growth plate and osteomalacia. Conventional treatment with combinations of oral inorganic phosphate and active vitamin D analogs enhances bone calcification, but the efficacy of conventional treatment is insufficient for adult XLH patients to achieve an acceptable quality of life. Burosumab, a fully human monoclonal anti-FGF23 antibody, binds and inhibits FGF23, correcting hypophosphatemia and hypovitaminosis D. This review describes a typical adult with XLH and summarizes the results of clinical trials of burosumab in adults with XLH.
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17
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Tajima T, Hasegawa Y. Treatment of X-Linked Hypophosphatemia in Children. Endocrines 2022; 3:522-529. [DOI: 10.3390/endocrines3030042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [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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18
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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19
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Ni X, Guan W, Pang Q, Jin C, Gong Y, Liu W, Wang O, Li M, Xing X, Yu W, Jiang Y, Xia W. Bone microstructure evaluated by TBS and HR-pQCT in Chinese adults with X-linked hypophosphatemia. Bone 2022; 160:116423. [PMID: 35439616 DOI: 10.1016/j.bone.2022.116423] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [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: 01/01/2022] [Revised: 04/08/2022] [Accepted: 04/12/2022] [Indexed: 12/24/2022]
Abstract
X-linked hypophosphatemia (XLH) is the most common form of heritable hypophosphatemic rickets. Although generalized mineralization defects have been observed, elevated areal bone mineral density (aBMD) in the lumbar spine measured by dual-energy X-ray absorptiometry (DXA) has also been found in XLH. In contrast, high-resolution peripheral quantitative computed tomography (HR-pQCT) revealed lower volumetric BMD (vBMD) and damaged bone microstructure in the peripheral bone in XLH. Trabecular bone score (TBS), which can assess the trabecular microstructure in the lumbar spine, has not been explored in XLH. This study aimed to explore TBS and its correlations with biochemical indices and HR-pQCT parameters in adult XLH patients. A total of 66 patients with XLH (26 men and 40 women) aged 29.6 ± 9.6 years and 66 age- and sex-matched healthy controls were included. Z score of lumbar spine aBMD was relatively high [2.0 (0.6, 3.7)], with normal TBS (1.475 ± 0.129) in the XLH patients. HR-pQCT revealed larger total and trabecular area in the peripheral bone in the XLH group compared with the control group. In addition, lower trabecular and cortical vBMD, lower trabecular number with greater separation, and lower bone strength at both the radius and tibia were found in the XLH group compared with the control group. Smaller cortical area, lower thickness and higher porosity in the XLH group compared with controls were only found at the radius. TBS was not associated with any biochemical indices, while better HR-pQCT parameters correlated with higher serum phosphate and lower ALP levels. TBS was positively related with aBMD but not HR-pQCT parameters. In conclusion, adult patients with XLH had high bone mass and normal TBS in the lumbar spine but compromised microarchitecture and bone strength in the peripheral bone. This finding indicated a site-specific effect of the disease on the skeleton in the XLH patients.
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Affiliation(s)
- Xiaolin Ni
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Wenmin Guan
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Qianqian Pang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Chenxi Jin
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Yiyi Gong
- Central Research Laboratory, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Wei Liu
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Ou Wang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Mei Li
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Xiaoping Xing
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Wei Yu
- Department of Radiology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Yan Jiang
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China.
| | - Weibo Xia
- Department of Endocrinology, Key Laboratory of Endocrinology, National Commission of Health, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China.
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20
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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: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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21
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Bollerslev J, Rejnmark L, Zahn A, Heck A, Appelman-Dijkstra NM, Cardoso L, Hannan FM, Cetani F, Sikjaer T, Formenti AM, Björnsdottir S, Schalin-Jäntti C, Belaya Z, Gibb F, Lapauw B, Amrein K, Wicke C, Grasemann C, Krebs M, Ryhänen E, Makay Ö, Minisola S, Gaujoux S, Bertocchio JP, Hassan-Smith Z, Linglart A, Winter EM, Kollmann M, Zmierczak HG, Tsourdi E, Pilz S, Siggelkow H, Gittoes N, Marcocci C, Kamenický P. European Expert Consensus on Practical Management of Specific Aspects of Parathyroid Disorders in Adults and in Pregnancy: Recommendations of the ESE Educational Program of Parathyroid Disorders. Eur J Endocrinol 2022; 186:R33-R63. [PMID: 34863037 PMCID: PMC8789028 DOI: 10.1530/eje-21-1044] [Citation(s) in RCA: 56] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/03/2021] [Indexed: 11/17/2022]
Abstract
This European expert consensus statement provides recommendations for the diagnosis and management of primary hyperparathyroidism (PHPT), chronic hypoparathyroidism in adults (HypoPT), and parathyroid disorders in relation to pregnancy and lactation. Specified areas of interest and unmet needs identified by experts at the second ESE Educational Program of Parathyroid Disorders (PARAT) in 2019, were discussed during two virtual workshops in 2021, and subsequently developed by working groups with interest in the specified areas. PHPT is a common endocrine disease. However, its differential diagnosing to familial hypocalciuric hypercalcemia (FHH), the definition and clinical course of normocalcemic PHPT, and the optimal management of its recurrence after surgery represent areas of uncertainty requiring clarifications. HypoPT is an orphan disease characterized by low calcium concentrations due to insufficient PTH secretion, most often secondary to neck surgery. Prevention and prediction of surgical injury to the parathyroid glands are essential to limit the disease-related burden. Long-term treatment modalities including the place for PTH replacement therapy and the optimal biochemical monitoring and imaging surveillance for complications to treatment in chronic HypoPT, need to be refined. The physiological changes in calcium metabolism occurring during pregnancy and lactation modify the clinical presentation and management of parathyroid disorders in these periods of life. Modern interdisciplinary approaches to PHPT and HypoPT in pregnant and lactating women and their newborns children are proposed. The recommendations on clinical management presented here will serve as background for further educational material aimed for a broader clinical audience, and were developed with focus on endocrinologists in training.
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Affiliation(s)
- Jens Bollerslev
- Faculty of Medicine, University of Oslo, Oslo, Norway
- Section of Specialized Endocrinology, Department of Endocrinology, Medical Clinic, Oslo University Hospital, Oslo, Norway
- Correspondence should be addressed to J Bollerslev Email
| | - Lars Rejnmark
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Alexandra Zahn
- Schön-Klinik Hamburg, Department of Endocrine Surgery, Hamburg, Germany
| | - Ansgar Heck
- Faculty of Medicine, University of Oslo, Oslo, Norway
- Section of Specialized Endocrinology, Department of Endocrinology, Medical Clinic, Oslo University Hospital, Oslo, Norway
| | - Natasha M Appelman-Dijkstra
- Division of Endocrinology, Department of Medicine, Leiden University Medical Center (LUMC), Leiden, the Netherlands
| | - Luis Cardoso
- Centro Hospitalar e Universitário de Coimbra, i3S – Instituto de Investigação e Inovação em Saúde da Universidade do Porto, Porto, Portugal
| | - Fadil M Hannan
- Nuffield Department of Women’s and Reproductive Health, University of Oxford, Oxford, UK
| | - Filomena Cetani
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Tanja Sikjaer
- Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Aarhus, Denmark
| | - Anna Maria Formenti
- Institute of Endocrine and Metabolic Sciences, Vita-Salute San Raffaele University, IRCCS San Raffaele Hospital, Milan, Italy
| | - Sigridur Björnsdottir
- Department of Endocrinology, Metabolism and Diabetes, Karolinska University Hospital, Stockholm, Sweden
| | - Camilla Schalin-Jäntti
- Endocrinology, Abdominal Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Zhanna Belaya
- The National Medical Research Centre for Endocrinology, Moscow, Russia
| | - Fraser Gibb
- Edinburgh Centre for Endocrinology & Diabetes, Royal Infirmary of Edinburgh, Edinburgh, UK
| | - Bruno Lapauw
- Department of Endocrinology, Ghent University Hospital, Ghent, Belgium
| | - Karin Amrein
- Division of Endocrinology and Diabetology, Medical University of Graz, Graz, Austria
| | - Corinna Wicke
- Thyroid Center, Luzerner Kantonsspital, Luzern, Switzerland
| | - Corinna Grasemann
- Division of Rare Diseases, Department of Pediatrics, St. Josef-Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Michael Krebs
- Division of Endocrinology and Metabolism, Department of Internal Medicine III, Medical University of Vienna, Vienna, Austria
| | - Eeva Ryhänen
- Endocrinology, Abdominal Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Özer Makay
- Division of Endocrine Surgery, Department of General Surgery, Ege University Hospital, Izmir, Turkey
| | - Salvatore Minisola
- Department of Internal Medicine and Medical Disciplines, Sapienza University of Rome, Rome, Italy
| | - Sébastien Gaujoux
- Department of Digestive, Hepatobiliary and Endocrine Surgery, Paris Descartes University, Cochin Hospital, Paris, France
| | - Jean-Philippe Bertocchio
- Assistance Publique-Hôpitaux de Paris (AP-HP), Pitié-Salpêtrière Hospital, Nephrology Department, Boulevard de l’Hôpital, Paris, France
| | - Zaki Hassan-Smith
- Department of Endocrinology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Agnès Linglart
- Université de Paris Saclay, AP-HP, Centre de Référence des Maladies Rares du Métabolisme du Calcium et du Phosphate, Filière OSCAR, Service d’Endocrinologie et Diabète de l’Enfant, Hôpital Bicêtre Paris Saclay, Le Kremlin Bicêtre, France
| | - Elizabeth M Winter
- Division of Endocrinology, Department of Medicine, Leiden University Medical Center (LUMC), Leiden, the Netherlands
| | - Martina Kollmann
- Department of Obstetrics and Gynecology, Medical University of Graz, Graz, Austria
| | - Hans-Georg Zmierczak
- Reference Centre for Rare Bone, Calcium and Phosphate Disorders – University Hospital Ghent, Ghent, Belgium
| | - Elena Tsourdi
- Center for Healthy Aging, Department of Medicine III, Technische Universität Dresden Medical Center, Dresden, Germany
| | - Stefan Pilz
- Division of Endocrinology and Diabetology, Medical University of Graz, Graz, Austria
| | - Heide Siggelkow
- Endokrinologikum Göttingen, Georg-August-University Göttingen, Göttingen, Germany
| | - Neil Gittoes
- Department of Endocrinology, University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - Claudio Marcocci
- Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy
| | - Peter Kamenický
- Université Paris-Saclay, Inserm, Physiologie et Physiopathologie Endocriniennes, Assistance Publique-Hôpitaux de Paris, Hôpital Bicêtre, Service d’Endocrinologie et des Maladies de la Reproduction, Centre de Référence des Maladies Rares du Métabolisme du Calcium et du Phosphate, Le Kremlin-Bicêtre, France
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Carpenter KA, Davison R, Shakthivel S, Anderson KD, Ko FC, Ross RD. Sclerostin antibody improves phosphate metabolism hormones, bone formation rates, and bone mass in adult Hyp mice. Bone 2022; 154:116201. [PMID: 34537437 PMCID: PMC8671249 DOI: 10.1016/j.bone.2021.116201] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [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: 06/14/2021] [Revised: 09/12/2021] [Accepted: 09/13/2021] [Indexed: 01/03/2023]
Abstract
X-linked hypophosphatemia (XLH) is caused by a loss-of-function mutation in the phosphate regulating gene with homology to endopeptidase located on the X chromosome (PHEX). Loss of functional PHEX results in elevated fibroblast growth factor 23 (FGF23), impaired phosphate reabsorption, and inhibited skeletal mineralization. Sclerostin, a protein produced primarily by osteocytes, suppresses bone formation by antagonizing canonical Wnt-signaling and is reported to be elevated in XLH patients. Our previous study reported that a monoclonal antibody to sclerostin (Scl-Ab) decreases FGF23 and increases phosphate and bone mass in growing Hyp mice (XLH murine model). In the current study, we investigated the efficacy of Scl-Ab in treating XLH pathophysiology in adult Hyp mice that are past the period of rapid skeletal growth (12 and 20-weeks old). We hypothesized that Scl-Ab would not only increase bone formation, bone strength and bone mass, but would also normalize phosphate regulating hormones, FGF23, parathyroid hormone (PTH), and vitamin 1,25(OH)2D. Scl-Ab treatment increased cortical area, trabecular bone volume fraction, trabecular bone formation rate, and the bending moment in both sexes of both age groups. Scl-Ab treatment suppressed circulating levels of intact FGF23 and c-term FGF23 in treated male and female wild-type and Hyp mice of both age groups and improved both vitamin 1,25(OH)2D and PTH. Scl-Ab treated Hyp mice also showed evidence of increased renal expression of the sodium-phosphate co-transporter, NPT2a, specifically in the female Hyp mice. Our study suggests that Scl-Ab treatment can improve several skeletal and metabolic pathologies associated with XLH, further establishes the role of sclerostin in the regulation of FGF23 and provides evidence that Scl-Ab can improve phosphate regulation by targeting the bone-renal axis.
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Affiliation(s)
- Kelsey A Carpenter
- Department of Cell & Molecular Medicine, Rush University Medical Center, Chicago, IL, United States of America
| | - Reid Davison
- Department of Cell & Molecular Medicine, Rush University Medical Center, Chicago, IL, United States of America
| | - Shruti Shakthivel
- Department of Cell & Molecular Medicine, Rush University Medical Center, Chicago, IL, United States of America
| | - Kyle D Anderson
- Department of Cell & Molecular Medicine, Rush University Medical Center, Chicago, IL, United States of America
| | - Frank C Ko
- Department of Cell & Molecular Medicine, Rush University Medical Center, Chicago, IL, United States of America; Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL, United States of America
| | - Ryan D Ross
- Department of Cell & Molecular Medicine, Rush University Medical Center, Chicago, IL, United States of America; Department of Orthopedic Surgery, Rush University Medical Center, Chicago, IL, United States of America.
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23
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Zavatta G, Altieri P, Vandi G, Vicennati V, Pagotto U, Vescini F. Phosphate Metabolism and Pathophysiology in Parathyroid Disorders and Endocrine Tumors. Int J Mol Sci 2021; 22:ijms222312975. [PMID: 34884774 PMCID: PMC8657508 DOI: 10.3390/ijms222312975] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 11/26/2021] [Accepted: 11/28/2021] [Indexed: 11/27/2022] Open
Abstract
The advent of new insights into phosphate metabolism must urge the endocrinologist to rethink the pathophysiology of widespread disorders, such as primary hyperparathyroidism, and also of rarer endocrine metabolic bone diseases, such as hypoparathyroidism and tumor-induced hypophosphatemia. These rare diseases of mineral metabolism have been and will be a precious source of new information about phosphate and other minerals in the coming years. The parathyroid glands, the kidneys, and the intestine are the main organs affecting phosphate levels in the blood and urine. Parathyroid disorders, renal tubule defects, or phosphatonin-producing tumors might be unveiled from alterations of such a simple and inexpensive mineral as serum phosphate. This review will present all these disorders from a ‘phosphate perspective’.
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Affiliation(s)
- Guido Zavatta
- Division of Endocrinology and Diabetes Prevention and Care, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, Via Massarenti 9, 40138 Bologna, Italy; (G.Z.); (P.A.); (G.V.); (V.V.); (U.P.)
| | - Paola Altieri
- Division of Endocrinology and Diabetes Prevention and Care, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, Via Massarenti 9, 40138 Bologna, Italy; (G.Z.); (P.A.); (G.V.); (V.V.); (U.P.)
| | - Giulia Vandi
- Division of Endocrinology and Diabetes Prevention and Care, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, Via Massarenti 9, 40138 Bologna, Italy; (G.Z.); (P.A.); (G.V.); (V.V.); (U.P.)
| | - Valentina Vicennati
- Division of Endocrinology and Diabetes Prevention and Care, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, Via Massarenti 9, 40138 Bologna, Italy; (G.Z.); (P.A.); (G.V.); (V.V.); (U.P.)
| | - Uberto Pagotto
- Division of Endocrinology and Diabetes Prevention and Care, IRCCS Azienda Ospedaliero-Universitaria di Bologna, Department of Medical and Surgical Sciences (DIMEC), Alma Mater Studiorum University of Bologna, Via Massarenti 9, 40138 Bologna, Italy; (G.Z.); (P.A.); (G.V.); (V.V.); (U.P.)
| | - Fabio Vescini
- Endocrinology and Metabolism Unit, University Hospital Udine, 33100 Udine, Italy
- Correspondence:
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24
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Figueres L, Beck-Cormier S, Beck L, Marks J. The Complexities of Organ Crosstalk in Phosphate Homeostasis: Time to Put Phosphate Sensing Back in the Limelight. Int J Mol Sci 2021; 22:5701. [PMID: 34071837 PMCID: PMC8199323 DOI: 10.3390/ijms22115701] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 05/13/2021] [Accepted: 05/21/2021] [Indexed: 12/16/2022] Open
Abstract
Phosphate homeostasis is essential for health and is achieved via interaction between the bone, kidney, small intestine, and parathyroid glands and via intricate processes involving phosphate transporters, phosphate sensors, and circulating hormones. Numerous genetic and acquired disorders are associated with disruption in these processes and can lead to significant morbidity and mortality. The role of the kidney in phosphate homeostasis is well known, although it is recognized that the cellular mechanisms in murine models and humans are different. Intestinal phosphate transport also appears to differ in humans and rodents, with recent studies demonstrating a dominant role for the paracellular pathway. The existence of phosphate sensing has been acknowledged for decades; however, the underlying molecular mechanisms are poorly understood. At least three phosphate sensors have emerged. PiT2 and FGFR1c both act as phosphate sensors controlling Fibroblast Growth Factor 23 secretion in bone, whereas the calcium-sensing receptor controls parathyroid hormone secretion in response to extracellular phosphate. All three of the proposed sensors are expressed in the kidney and intestine but their exact function in these organs is unknown. Understanding organ interactions and the mechanisms involved in phosphate sensing requires significant research to develop novel approaches for the treatment of phosphate homeostasis disorders.
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Affiliation(s)
- Lucile Figueres
- Department of Neuroscience, Physiology and Pharmacology, Royal Free Campus, University College London, London NW3 2PF, UK;
- CHU de Nantes, Université de Nantes, F-44042 Nantes, France
| | - Sarah Beck-Cormier
- Inserm, UMR 1229, RMeS Regenerative Medicine and Skeleton, Université de Nantes, ONIRIS, F-44042 Nantes, France; (S.B.-C.); (L.B.)
| | - Laurent Beck
- Inserm, UMR 1229, RMeS Regenerative Medicine and Skeleton, Université de Nantes, ONIRIS, F-44042 Nantes, France; (S.B.-C.); (L.B.)
| | - Joanne Marks
- Department of Neuroscience, Physiology and Pharmacology, Royal Free Campus, University College London, London NW3 2PF, UK;
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25
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McKenna MJ, Crowley RK, Twomey PJ, Kilbane MT. Renal Phosphate Handling: Independent Effects of Circulating FGF23, PTH, and Calcium. JBMR Plus 2021; 5:e10437. [PMID: 33615106 PMCID: PMC7872336 DOI: 10.1002/jbm4.10437] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 11/13/2020] [Indexed: 12/25/2022] Open
Abstract
Excess fibroblast growth factor 23 (FGF23), excess PTH, and an increase in extracellular calcium cause hypophosphatemia by lowering the maximum renal phosphate reabsorption threshold (TmP/GFR). We recently reported two cases of X-linked hypophosphatemia (XLH) with severe tertiary hyperparathyroidism who had normalization of TmP/GFR upon being rendered hypoparathyroid following total parathyroidectomy, despite marked excess in both C-terminal FGF23 (cFGF23) and intact FGF23 (iFGF23). We explored the effects of FGF23, PTH, and calcium on TmP/GFR in a cross-sectional study (n = 74) across a spectrum of clinical cases with abnormalities in TmP/GFR, PTH, and FGF23. This comprised three groups: FGF23-dependent hypophosphatemia (n = 27), hypoparathyroidism (HOPT; n = 17), and chronic kidney disease (n = 30). Measurements included TmP/GFR, cFGF23, PTH, ionized calcium, vitamin D metabolites, and bone turnover markers. The combined effect of cFGF23, PTH, and ionized calcium on TmP/GFR was modeled using hierarchical multiple regression and was probed by moderation analysis with PROCESS. Modeling analysis showed independent effects on TmP/GFR by cFGF23, PTH, and ionized calcium in conjunction with a weak but significant effect of the interaction term for PTH and FGF23; probing showed that the effect was most prominent during PTH deficiency. Teriparatide 20 μg daily was self-administered for 28 days by one case of X-linked hypophosphatemia with hypoparathyroidism (XLH-HOPT) to assess the response of TmP/GFR, cFGF23, iFGF23, nephrogenous cyclic adenosine monophosphate (NcAMP), vitamin D metabolites, and bone turnover markers. After 28 days, TmP/GFR was lowered from 1.10 mmol/L to 0.48 mmol/L; this was accompanied by increases in NcAMP, ionized calcium, and bone turnover markers. In conclusion, the effect of FGF23 excess on TmP/GFR is altered by PTH such that the effect is ameliorated by hypoparathyroidism and the effect is augmented by hyperparathyroidism. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC. on behalf of American Society for Bone and Mineral Research.
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Affiliation(s)
- Malachi J McKenna
- UCD School of MedicineUniversity College DublinDublinIreland
- Department of Clinical ChemistrySt. Vincent's University HospitalDublinIreland
- Department of EndocrinologySt. Vincent's University HospitalDublinIreland
| | - Rachel K Crowley
- UCD School of MedicineUniversity College DublinDublinIreland
- Department of Clinical ChemistrySt. Vincent's University HospitalDublinIreland
- Department of EndocrinologySt. Vincent's University HospitalDublinIreland
| | - Patrick J Twomey
- UCD School of MedicineUniversity College DublinDublinIreland
- Department of Clinical ChemistrySt. Vincent's University HospitalDublinIreland
| | - Mark T Kilbane
- UCD School of MedicineUniversity College DublinDublinIreland
- Department of Clinical ChemistrySt. Vincent's University HospitalDublinIreland
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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