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Ertl DA, Le Lorier J, Gleiss A, Trabado S, Bensignor C, Audrain C, Zhukouskaya V, Coutant R, Berkenou J, Rothenbuhler A, Haeusler G, Linglart A. Growth pattern in children with X-linked hypophosphatemia treated with burosumab and growth hormone. Orphanet J Rare Dis 2022; 17:412. [PMID: 36371259 PMCID: PMC9652849 DOI: 10.1186/s13023-022-02562-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 10/23/2022] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND X-linked hypophosphatemia (XLH) is characterized by increased serum concentrations of fibroblast growth factor 23 (FGF23), hypophosphatemia and insufficient endogenous synthesis of calcitriol. Beside rickets, odonto- and osteomalacia, disproportionate short stature is seen in most affected individuals. Vitamin D analogs and phosphate supplements, i.e., conventional therapy, can improve growth especially when started early in life. Recombinant human growth hormone (rhGH) therapy in XLH children with short stature has positive effects, although few reports are available. Newly available treatment (burosumab) targeting increased FGF23 signaling leads to minimal improvement of growth in XLH children. So far, we lack data on the growth of XLH children treated with concomitant rhGH and burosumab therapies. RESULTS Thirty-six patients received burosumab for at least 1 year after switching from conventional therapy. Of these, 23 received burosumab alone, while the others continued rhGH therapy after switching to burosumab. Children treated with burosumab alone showed a minimal change in height SDS after 1 year (mean ± SD 0.0 ± 0.3 prepubertal vs. 0.1 ± 0.3 pubertal participants). In contrast, rhGH clearly improved height during the first year of treatment before initiating burosumab (mean ± SD of height gain 1.0 ± 0.4); patients continued to gain height during the year of combined burosumab and rhGH therapies (mean ± SD height gain 0.2 ± 0.1). As expected, phosphate serum levels normalized upon burosumab therapy. No change in serum calcium levels, urinary calcium excretion, or 25-OHD levels was seen, though 1,25-(OH)2D increased dramatically under burosumab therapy. CONCLUSION To our knowledge, this is the first study on growth under concomitant rhGH and burosumab treatments. We did not observe any safety issue in this cohort of patients which is one of the largest in Europe. Our data suggest that continuing treatment with rhGH after switching from conventional therapy to burosumab, if the height prognosis is compromised, might be beneficial for the final height.
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Affiliation(s)
- Diana-Alexandra Ertl
- grid.413784.d0000 0001 2181 7253AP-HP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Saclay Hospital, 78 Rue du Général Leclerc, 94270 Le Kremlin Bicêtre, France ,grid.460789.40000 0004 4910 6535University Paris Saclay, Le Kremlin-Bicêtre, France ,grid.50550.350000 0001 2175 4109AP-HP, Department of Endocrinology and Diabetology for Children and Department of Adolescent Medicine, Bicêtre Paris-Saclay Hospital, Le Kremlin-Bicêtre, France ,grid.22937.3d0000 0000 9259 8492Department of Pediatrics and Adolescent Medicine, Division of Pulmonology, Allergology and Endocrinology, Medical University of Vienna, Vienna, Austria ,Vienna Bone and Growth Center, Vienna, Austria
| | - Justin Le Lorier
- grid.413784.d0000 0001 2181 7253AP-HP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Saclay Hospital, 78 Rue du Général Leclerc, 94270 Le Kremlin Bicêtre, France ,grid.460789.40000 0004 4910 6535University Paris Saclay, Le Kremlin-Bicêtre, France ,grid.50550.350000 0001 2175 4109AP-HP, Department of Endocrinology and Diabetology for Children and Department of Adolescent Medicine, Bicêtre Paris-Saclay Hospital, Le Kremlin-Bicêtre, France
| | - Andreas Gleiss
- grid.22937.3d0000 0000 9259 8492Center for Medical Statistics, Informatics, and Intelligent Systems, Medical University of Vienna, Vienna, Austria
| | - Séverine Trabado
- grid.7429.80000000121866389Department of Molecular Genetics, Pharmacogenetics and Hormonology, Inserm U1185 and University Paris Saclay, AP-HP Bicêtre Paris-Saclay Hospital, Le Kremlin-Bicêtre, France
| | | | - Christelle Audrain
- grid.413784.d0000 0001 2181 7253AP-HP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Saclay Hospital, 78 Rue du Général Leclerc, 94270 Le Kremlin Bicêtre, France ,grid.460789.40000 0004 4910 6535University Paris Saclay, Le Kremlin-Bicêtre, France
| | - Volha Zhukouskaya
- grid.413784.d0000 0001 2181 7253AP-HP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Saclay Hospital, 78 Rue du Général Leclerc, 94270 Le Kremlin Bicêtre, France ,grid.508487.60000 0004 7885 7602Laboratory Orofacial Pathologies, Imaging and Biotherapies URP2496 and FHU-DDS-Net, Dental School, Platforme d´Imaginerie du Vivant (PIV), University Paris Cite, Montrouge, France ,grid.508487.60000 0004 7885 7602AP-HP Cochin Hospital, Department of Diabetology, University Paris Cite, Paris, France
| | - Régis Coutant
- grid.411147.60000 0004 0472 0283Department of Pediatric Endocrinology and Diabetes, CHU Angers, Anger, France
| | - Jugurtha Berkenou
- grid.413784.d0000 0001 2181 7253AP-HP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Saclay Hospital, 78 Rue du Général Leclerc, 94270 Le Kremlin Bicêtre, France ,grid.460789.40000 0004 4910 6535University Paris Saclay, Le Kremlin-Bicêtre, France
| | - Anya Rothenbuhler
- grid.413784.d0000 0001 2181 7253AP-HP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Saclay Hospital, 78 Rue du Général Leclerc, 94270 Le Kremlin Bicêtre, France ,grid.460789.40000 0004 4910 6535University Paris Saclay, Le Kremlin-Bicêtre, France ,grid.50550.350000 0001 2175 4109AP-HP, Department of Endocrinology and Diabetology for Children and Department of Adolescent Medicine, Bicêtre Paris-Saclay Hospital, Le Kremlin-Bicêtre, France
| | - Gabriele Haeusler
- grid.22937.3d0000 0000 9259 8492Department of Pediatrics and Adolescent Medicine, Division of Pulmonology, Allergology and Endocrinology, Medical University of Vienna, Vienna, Austria ,Vienna Bone and Growth Center, Vienna, Austria
| | - Agnès Linglart
- grid.413784.d0000 0001 2181 7253AP-HP, Reference Center for Rare Disorders of the Calcium and Phosphate Metabolism, Filière OSCAR and Platform of Expertise for Rare Diseases Paris-Sud, Bicêtre Paris-Saclay Hospital, 78 Rue du Général Leclerc, 94270 Le Kremlin Bicêtre, France ,grid.460789.40000 0004 4910 6535University Paris Saclay, Le Kremlin-Bicêtre, France ,grid.50550.350000 0001 2175 4109AP-HP, Department of Endocrinology and Diabetology for Children and Department of Adolescent Medicine, Bicêtre Paris-Saclay Hospital, Le Kremlin-Bicêtre, France
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Abstract
BACKGROUND Conventional treatment of X-linked hypophosphatemia with oral phosphate and calcitriol can heal rickets, but it does not always raise serum phosphate concentrations significantly, nor does it always normalize linear growth. Some clinical trials suggest that combining recombinant human growth hormone therapy with conventional treatment improves growth velocity, phosphate retention, and bone mineral density, but some clinical trials suggest that it appears to aggravate the pre-existent disproportionate stature of such children. This is an updated version of a previously published review. OBJECTIVES To determine whether recombinant human growth hormone therapy for children with X-linked hypophosphatemia is associated with changes in longitudinal growth, mineral metabolism, endocrine function, renal function, bone mineral density, body proportions, and also with any adverse effects. SEARCH METHODS We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register which comprises references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. In addition, we searched the Cochrane Central Register of Controlled Trials, Ovid MEDLINE and the reference lists of identified trials and other reviews. We also undertook some additional handsearching of relevant journals and conference proceedings. Date of the most recent search: 12 January 2021 SELECTION CRITERIA: All randomized controlled studies or quasi-randomized controlled studies comparing growth hormone (alone or combined with conventional treatment) with either placebo or conventional treatment alone in children with X-linked hypophosphatemia. DATA COLLECTION AND ANALYSIS Two authors independently assessed studies for risk of bias and extracted data from eligible studies. GRADE criteria were used to assess the certainty of the evidence for each outcome. MAIN RESULTS We included two studies (20 participants) in the review. In one cross-over study, results showed that recombinant human growth hormone therapy may improve the height standard deviation (SDS) score (z score), but we are unsure whether the intervention was the reason behind a transient increase in serum phosphate and tubular maximum for phosphate reabsorption. In the second, parallel study, treatment may also have improved the height SDS from baseline in the rhGH group compared to the control group, although no significant difference was seen between groups after three years, MD 0.50 SDS (95 % CI -0.54 to 1.54) (low-certainty evidence). The treatment was possibly well-tolerated during both studies with only transient adverse effects seen in three participants (low-certainty evidence). We are uncertain whether growth hormone improves serum phosphate levels or change in TmP/GFR (very low-certainty evidence). The treatment may make little or no difference to alkaline phosphatase levels (low-certainty evidence). AUTHORS' CONCLUSIONS We do not have enough high-certainty evidence to recommend the use of recombinant human growth hormone therapy in children with X-linked hypophosphatemia.
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Affiliation(s)
- Sherie Smith
- Division of Child Health, Obstetrics & Gynaecology (COG), School of Medicine, University of Nottingham, Nottingham, UK
| | - Tracey Remmington
- Department of Women's and Children's Health, University of Liverpool, Liverpool, UK
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Abstract
Our understanding of the regulation of phosphate balance has benefited tremendously from the molecular identification and characterization of genetic defects leading to a number of rare inherited or acquired disorders affecting phosphate homeostasis. The identification of the key phosphate-regulating hormone, fibroblast growth factor 23 (FGF23), as well as other molecules that control its production, such as the glycosyltransferase GALNT3, the endopeptidase PHEX, and the matrix protein DMP1, and molecules that function as downstream effectors of FGF23 such as the longevity factor Klotho and the phosphate transporters NPT2a and NPT2c, has permitted us to understand the complex interplay that exists between the kidneys, bone, parathyroid, and gut. Such insights from genetic disorders have allowed not only the design of potent targeted treatment of FGF23-dependent hypophosphatemic conditions, but also provide clinically relevant observations related to the dysregulation of mineral ion homeostasis in health and disease.
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Affiliation(s)
- Marta Christov
- Division of Nephrology, Department of Medicine, New York Medical College, Valhalla, NY, USA
| | - Harald Jüppner
- Endocrine Unit and Pediatric Nephrology Unit, Massachusetts General Hospital, Boston, MA, USA; Harvard Medical School, Boston, MA, USA.
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Meyerhoff N, Haffner D, Staude H, Wühl E, Marx M, Beetz R, Querfeld U, Holder M, Billing H, Rabl W, Schröder C, Hiort O, Brämswig JH, Richter-Unruh A, Schnabel D, Živičnjak M. Effects of growth hormone treatment on adult height in severely short children with X-linked hypophosphatemic rickets. Pediatr Nephrol 2018; 33:447-456. [PMID: 29058153 DOI: 10.1007/s00467-017-3820-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 08/30/2017] [Accepted: 09/17/2017] [Indexed: 12/11/2022]
Abstract
BACKGROUND We recently showed that a 3-year growth hormone (GH) treatment improves linear growth in severely short children with X-linked hypophosphatemic rickets (XLH). It is unknown if GH therapy increases adult height in XLH patients. METHODS We carried out a follow-up analysis of a randomized controlled open-label GH study in short prepubertal children with XLH on phosphate and active vitamin D treatment. The changes in SD scores (SDS) of height, sitting height, leg and arm length, and sitting height index (i.e., the ratio between sitting height and height) were analyzed in 11 out of 16 patients followed-up until adult height. RESULTS At baseline, XLH patients showed disproportionately short stature with reduced standardized height (-3.2 ± 0.6), sitting height (-1.7 ± 0.6), leg (-3.7 ± 0.7) and arm (-2.5 ± 0.8) length, and markedly elevated sitting height index (3.3 ± 0.6; each p < 0.01 versus healthy children). In GH-treated patients, adult height, sitting height, leg length, and arm length exceeded baseline values by 0.7 SDS, 1.7 SDS, 0.7 SDS, and 1.2 SDS respectively, although this was only significant for sitting height. In controls, no significant changes in linear body dimensions were noted. Adult height did not statistically differ between groups (-2.4 ± 0.7 vs -3.3 ± 1.2, p = 0.082). GH did not exaggerate body disproportion. CONCLUSIONS Growth hormone treatment did not significantly increase adult height in this group of short children with XLH, which may be at least partly due to the small number of patients included in our study.
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Affiliation(s)
- Nadine Meyerhoff
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Dieter Haffner
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Hagen Staude
- University Children's Hospital Rostock, Rostock, Germany
| | - Elke Wühl
- University Children's Hospital Heidelberg, Heidelberg, Germany
| | - Michaela Marx
- University Children's Hospital Erlangen, Erlangen, Germany
| | - Rolf Beetz
- University Children's Hospital Mainz, Mainz, Germany
| | - Uwe Querfeld
- Department of Pediatric Nephrology, University Children's Hospital, Charité, Berlin, Germany
| | - Martin Holder
- Department of Pediatrics, Klinikum Stuttgart, Olgahospital, Stuttgart, Germany
| | - Heiko Billing
- University Children's Hospital Tübingen, Tübingen, Germany
| | - Wolfgang Rabl
- Children's Hospital of the Technical University Munich, Munich, Germany
| | - Carmen Schröder
- University Children's Hospital Greifswald, Greifswald, Germany
| | - Olaf Hiort
- Division of Pediatric Endocrinology and Diabetes, Department of Pediatrics and Adolescent Medicine, University of Lübeck, Lübeck, Germany
| | | | | | - Dirk Schnabel
- Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Center for Chronically Sick Children, Pediatric Endocrinology, Berlin, Germany
| | - Miroslav Živičnjak
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany.
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Rothenbuhler A, Esterle L, Gueorguieva I, Salles JP, Mignot B, Colle M, Linglart A. Two-year recombinant human growth hormone (rhGH) treatment is more effective in pre-pubertal compared to pubertal short children with X-linked hypophosphatemic rickets (XLHR). Growth Horm IGF Res 2017; 36:11-15. [PMID: 28822957 DOI: 10.1016/j.ghir.2017.08.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 08/03/2017] [Accepted: 08/14/2017] [Indexed: 01/20/2023]
Abstract
CONTEXT Twenty-five to 40% of patients with well-controlled X-linked hypophosphatemic rickets (XLHR) have a final height under -2 SDS. Previous studies have shown that recombinant human growth hormone (rhGH) treatment improves linear growth in short children with XLHR. OBJECTIVE We studied the effectiveness of rhGH treatment in children with XLHR in a larger cohort. DESIGN Monocentric, prospective, non-randomized trial. SETTING University hospital in France. PATIENTS 19 patients with XLHR and a mutation in the PHEX gene. Six male and 6 female Tanner stage 1 patients (age 6.1±2.4years) and 4 male and 3 female Tanner stage 2 patients (age 13.1±1years). At inclusion, height SDS was -2.35±0.8 SDS and growth velocity was -1.12±1.2 SDS. INTERVENTION 2years of treatment with 67mcg/kg/day of rhGH at initiation. Every three months rhGH dosage was adjusted using an IGF-1 dosing protocol. MAIN OUTCOME MEASURES Comparison in change from baseline to year 2 in height and growth velocity. RESULTS Height SDS improved from -2.35±0.8 SDS at baseline, to -1.62±0.8 SDS (p=0.01) after one and to -1.2±1 SDS (p=0.04) after two years of rhGH treatment. There was a strong correlation (r2=0.6104, p<0.0001) between the age of onset of rhGH treatment and the number of cm gained over the study period. Pre-pubertal patients height SDS improved compared to baseline height SDS after one (-1.5±0.7, p<0.03) and two (-0.96±1, p<0.03) years of rhGH treatment. In pubertal patients there was no significant improvement in height SDS after one year (-1.75±1) and after two years (-1.7±0.8) of rhGH treatment. CONCLUSION Two-year rhGH treatment is effective to treat short stature in XLHR children. Pre-pubertal children responded better to rhGH. CLINICAL TRIAL REGISTRATION NUMBER NCT02720770.
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Affiliation(s)
- Anya Rothenbuhler
- Department of Pediatric Endocrinology and Diabetes, Centre de Reference des Maladies Rares du Metabolisme du Calcium et du Phophore, Pole I3E, Bicetre Hospital, Paris Sud University, APHP, 94275 Le Kremlin Bicetre, France.
| | - Laure Esterle
- Department of Pediatric Endocrinology and Diabetes, Centre de Reference des Maladies Rares du Metabolisme du Calcium et du Phophore, Pole I3E, Bicetre Hospital, Paris Sud University, APHP, 94275 Le Kremlin Bicetre, France
| | - Iva Gueorguieva
- Department of Pediatric Endocrinology and Diabetes, Centre de Reference des Maladies Rares du Metabolisme du Calcium et du Phophore, Pole I3E, Bicetre Hospital, Paris Sud University, APHP, 94275 Le Kremlin Bicetre, France
| | - Jean-Pierre Salles
- Unite d'Endocrinologie, Maladies Osseuses, Hopital des Enfants, Toulouse University Hospital, INSERM UMR 1043 (CPTP), University of Toulouse Paul Sabatier, Toulouse, France
| | - Brigitte Mignot
- Service de Pediatrie, Centre Hospitalier Regional Universitaire, Hopital Jean Minjoz, Besancon, France
| | | | - Agnes Linglart
- Department of Pediatric Endocrinology and Diabetes, Centre de Reference des Maladies Rares du Metabolisme du Calcium et du Phophore, Pole I3E, Bicetre Hospital, Paris Sud University, APHP, 94275 Le Kremlin Bicetre, France
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Goldsweig BK, Carpenter TO. Hypophosphatemic rickets: lessons from disrupted FGF23 control of phosphorus homeostasis. Curr Osteoporos Rep 2015; 13:88-97. [PMID: 25620749 DOI: 10.1007/s11914-015-0259-y] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Fibroblast growth factor-23 (FGF23) regulates phosphate reabsorption in the kidney and therefore plays an essential role in phosphate balance in humans. There is a host of defects that ultimately lead to excess FGF23 levels and thereby cause renal phosphate wasting and hypophosphatemic rickets. We describe the genetic, pathophysiologic, and clinical aspects of this group of disorders with a focus on X-linked hypophosphatemia (XLH), the best characterized of these abnormalities. We also discuss autosomal dominant hypophosphatemic rickets (ADHR), autosomal recessive hypophosphatemic rickets (ARHR) and tumor-induced osteomalacia (TIO) in addition to other rarer FGF23-mediated conditions. We contrast the FGF23-mediated disorders with FGF23-independent hypophosphatemia, specifically hypophosphatemic rickets with hypercalciuria (HHRH). Errant diagnosis of hypophosphatemic disorders is common. This review aims to enhance the recognition and appropriate diagnosis of hypophosphatemia and to guide appropriate treatment.
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Affiliation(s)
- Bracha K Goldsweig
- Department of Pediatrics (Endocrinology), Yale University School of Medicine, 333 Cedar Street, PO Box 208064, New Haven, CT, 06520, USA,
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Hypophosphatemic rickets: etiology, clinical features and treatment. EUROPEAN JOURNAL OF ORTHOPAEDIC SURGERY AND TRAUMATOLOGY 2014; 25:221-6. [DOI: 10.1007/s00590-014-1496-y] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/26/2014] [Accepted: 06/02/2014] [Indexed: 02/02/2023]
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Carpenter TO. The expanding family of hypophosphatemic syndromes. J Bone Miner Metab 2012; 30:1-9. [PMID: 22167381 DOI: 10.1007/s00774-011-0340-2] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2011] [Accepted: 11/21/2011] [Indexed: 01/07/2023]
Abstract
Investigation of X-linked hypophosphatemia (XLH) has led to the identification of a novel phosphate-regulating homeostatic system. Initially considered vitamin D-refractory rickets, renal phosphate wasting was identified as the cardinal biochemical feature of XLH and several related disorders. Current therapy employs calcitriol and phosphate, which usually improves, but does not completely heal deformities and short stature. Later complications of XLH include development of osteophytes, entheses, and osteoarthritis. The mutated gene in XLH, PHEX, is expressed in osteocytes, but its role in the pathogenesis of phosphate wasting is poorly understood. Many hypophosphatemic disorders are mediated by FGF23, a unique fibroblast growth factor with endocrine properties. Renal action of FGF23 leads to reduced expression of type II sodium-phosphate co-transporters, as well as reduced expression of CYP27B1, which encodes vitamin D 1α-hydroxylase. FGF23-mediated hypophosphatemia is characterized by inappropriately normal circulating 1,25-dihydroxyvitamin D together with renal phosphate wasting. The FGF23 system serves as a novel mechanism by which the mineralizing skeleton can communicate phosphate supply to the kidney and thereby mediate excretion or conservation of this important skeletal component. Other forms of FGF23-mediated hypophosphatemia represent various aberrations in this axis. Secretion of excess FGF23 (as in tumor-induced osteomalacia), and mutations preventing proteolytic cleavage of FGF23 result in similar clinical features. Other hypophosphatemic disorders are discussed.
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Affiliation(s)
- Thomas O Carpenter
- Department of Pediatrics (Endocrinology), Yale University School of Medicine, 333 Cedar Street, PO Box 208064, New Haven, CT 06520-8064, USA.
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Carpenter TO, Imel EA, Holm IA, Jan de Beur SM, Insogna KL. A clinician's guide to X-linked hypophosphatemia. J Bone Miner Res 2011; 26:1381-8. [PMID: 21538511 PMCID: PMC3157040 DOI: 10.1002/jbmr.340] [Citation(s) in RCA: 381] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2010] [Revised: 12/28/2010] [Accepted: 01/13/2011] [Indexed: 11/10/2022]
Abstract
X-linked hypophosphatemia (XLH) is the prototypic disorder of renal phosphate wasting, and the most common form of heritable rickets. Physicians, patients, and support groups have all expressed concerns about the dearth of information about this disease and the lack of treatment guidelines, which frequently lead to missed diagnoses or mismanagement. This perspective addresses the recommendation by conferees for the dissemination of concise and accessible treatment guidelines for clinicians arising from the Advances in Rare Bone Diseases Scientific Conference held at the NIH in October 2008. We briefly review the clinical and pathophysiologic features of the disorder and offer this guide in response to the conference recommendation, based on our collective accumulated experience in the management of this complex disorder.
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Affiliation(s)
| | - Erik A. Imel
- Indiana University School of Medicine, Indianapolis IN
| | - Ingrid A. Holm
- Division of Genetics, Program in Genomics, and the Manton Center for Orphan Disease Research, Children's Hospital Boston and Harvard Medical School, Boston, MA
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Zivičnjak M, Schnabel D, Billing H, Staude H, Filler G, Querfeld U, Schumacher M, Pyper A, Schröder C, Brämswig J, Haffner D. Age-related stature and linear body segments in children with X-linked hypophosphatemic rickets. Pediatr Nephrol 2011; 26:223-31. [PMID: 21120538 DOI: 10.1007/s00467-010-1705-9] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2010] [Revised: 09/14/2010] [Accepted: 10/09/2010] [Indexed: 01/08/2023]
Abstract
Children with X-linked hypophosphatemic rickets (XLH) are prone to severe stunting. A multicenter mixed-longitudinal study was conducted to assess age-related stature, sitting height, arm and leg length in XLH patients on continuous treatment with phosphate and calcitriol. Mean standard deviation scores (SDS) for all body dimensions were markedly reduced and differed significantly among each other at the initial and subsequent evaluations (baseline: stature -2.48 SDS; sitting height -0.99 SDS; arm length -1.81 SDS; leg length -2.90 SDS; each p<0.001). A strong association between stature and leg length (r (2)=0.87, p<0.001) was noted. Leg length SDS decreased progressively during childhood (2-9 years) and adolescence (12-15 years; each p<0.001). Sitting height SDS increased significantly during late childhood, indicating uncoupled growth of the legs and trunk and resulting in an ever increasing sitting height index (i.e. ratio of sitting height to stature; age 2 years 2.0 SDS; age 10 years 3.3 SDS; p<0.001) that was associated with the degree of stunting (r (2)=0.314, p<0.001). Mean serum phosphate levels were positively associated with stature and leg length, but negatively with sitting height index. Based on these results, we can conclude that growth of the legs and trunk is uncoupled in XLH and related to serum phosphate levels.
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Affiliation(s)
- Miroslav Zivičnjak
- Department of Pediatric Nephrology, Children's Hospital of Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
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11
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Vaisbich MH, Koch VH. Hypophosphatemic rickets: results of a long-term follow-up. Pediatr Nephrol 2006; 21:230-4. [PMID: 16252097 DOI: 10.1007/s00467-005-2077-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2004] [Revised: 06/28/2005] [Accepted: 07/07/2005] [Indexed: 01/31/2023]
Abstract
This study reports the benefits and side effects of conventional treatment, phosphate and calcitriol supplementation in patients with heritable hypophosphatemic rickets and a long-term follow-up, median of 60.9 months. The group is composed of 17 patients (ten girls). Sixteen patients presented with bone pain and/or deformities, and in one patient the diagnosis was radiological. All the patients had increased alkaline phosphatase, hypophosphatemia, decreased fractional phosphate tubular reabsorption (TRP) and maximum tubular phosphate reabsorption/glomerular filtration rate ratio (TPO4/GFR). Ten of 17 patients had metabolic acidosis, which was corrected only with the conventional treatment. Potassium citrate was prescribed to the patients who developed hypercalciuria. Excluding one patient with pulmonary dysfunction, the remaining 16 patients were divided into two groups according to the age at treatment onset (T0): group I (GI) > or =4 years (n =9) and GII <4 years (n =7). GI and GII had similar follow-up periods and treatment protocols. Seven out of nine GI patients underwent orthopedic surgery, in contrast to none of GII. Anthropometric data results showed that within each group there is no difference in weight and stature z -score at T0 and at the end of the observation (Tf), but, when both groups are compared, GII shows higher z-score for stature at T0 (p <0.05) and at Tf (p <0.05). Nephrocalcinosis developed in three cases and correlated with hypercalciuria (p <0.001) and dose of calcitriol (p =0.03). In conclusion, higher stature z-score is associated with early treatment. A careful protocol is recommended to detect such complications as nephrocalcinosis. We suggest potassium citrate for patients with hypercalciuria to avoid calcium precipitation.
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Affiliation(s)
- Maria Helena Vaisbich
- Pediatric Nephrology Unit, Instituto da Crianca Hospital das Clinicas, Faculdade de Medicina da Universidade de Sao Paulo, 04105-001 Sao Paulo, Brazil.
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Abstract
BACKGROUND Conventional treatment of X-linked hypophosphatemia with oral phosphate and calcitriol can heal rickets, but it does not always raise serum phosphate concentrations significantly, nor does it always normalize linear growth. Some clinical trials suggest that combining recombinant human growth hormone therapy with conventional treatment improves growth velocity, phosphate retention, and bone mineral density, but some clinical trials suggest that it appears to aggravate the pre-existent disproportionate stature of such children. OBJECTIVES To determine whether recombinant human growth hormone therapy for children with X-linked hypophosphatemia is associated with changes in longitudinal growth, mineral metabolism, endocrine function, renal function, bone mineral density, body proportions, and also with any adverse effects. SEARCH STRATEGY Relevant trials were identified from searching the Cochrane Central Register of Controlled Trials Issue 3, 2003 and Ovid MEDLINE 1966 to September 2003. Additional trials were identified from the reference lists of identified trials and other reviews. We also searched the Journal of Bone and Mineral Research (1986 to 2003) and proceedings of the American Society for Bone and Mineral Research Annual Meeting (1st to 24th). Date of most recent search: November 2003. SELECTION CRITERIA All randomized controlled trials or quasi-randomized controlled trials comparing growth hormone (alone or combined with conventional treatment) with either placebo or conventional treatment alone in children with X-linked hypophosphatemia. DATA COLLECTION AND ANALYSIS Two reviewers independently assessed trials for methodological quality and extracted data from eligible trials. MAIN RESULTS The searches identified five trials, of which one met the inclusion criteria, including a total of five participants. In this trial, rhGH therapy improved the height standard deviation score (z score), and transiently increased serum phosphate and tubular maximum for phosphate reabsorption. AUTHORS' CONCLUSIONS We have found no conclusive evidence to indicate that the use of recombinant human growth hormone therapy in children with XLH is associated with changes in longitudinal growth, mineral metabolism, endocrine, renal function, bone mineral density, body proportions, but it does not appear to have any adverse effects.
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Affiliation(s)
- Y Huiming
- Paediatrics Department, West China Second University Hospital, Sichuan University, Third Section of the People's South Street, Chengdu, Sichuan, China, 610041.
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Haffner D, Nissel R, Wühl E, Mehls O. Effects of growth hormone treatment on body proportions and final height among small children with X-linked hypophosphatemic rickets. Pediatrics 2004; 113:e593-6. [PMID: 15173542 DOI: 10.1542/peds.113.6.e593] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND X-linked hypophosphatemic rickets (XLH) is characterized by rickets, disproportionate short stature, and impaired renal phosphate reabsorption and vitamin D metabolism. Despite oral phosphate and vitamin D treatment, most children with XLH demonstrate reduced adult height. OBJECTIVE To determine the beneficial effects of recombinant human growth hormone (rhGH) therapy on body proportions and adult height among patients with XLH. METHODS Three initially prepubertal short children (age, 9.4-12.9 years) with XLH were treated with rhGH for 3.1 to 6.3 years until adult height was attained. RESULTS rhGH treatment led to sustained increases in standardized height for all children. The median adult height was 0.9 SD (range: 0.5-1.3 SD) greater than that at the initiation of rhGH treatment and exceeded the predicted adult height by 6.2 cm (range: 5.3-9.8 cm). However, longitudinal growth of the trunk was stimulated more than leg growth. During rhGH treatment, the standardized sitting height increased by 1.6 SD (range: 1.1-2.7 SD), compared with baseline values. In contrast, the median subischial leg length did not change consistently (median change: 0.3 SD; range: -0.1 to 0.6 SD). CONCLUSION The increase in final height after rhGH treatment is of potential benefit for children with XLH. However, the exaggeration of disproportionate truncal growth observed for our prepubertal patients is a potential negative effect of treatment and should be confirmed with additional studies.
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Affiliation(s)
- Dieter Haffner
- Department of Pediatric Nephrology, University Hospital Charité, Berlin, Germany
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Baroncelli GI, Bertelloni S, Ceccarelli C, Saggese G. Effect of growth hormone treatment on final height, phosphate metabolism, and bone mineral density in children with X-linked hypophosphatemic rickets. J Pediatr 2001; 138:236-43. [PMID: 11174622 DOI: 10.1067/mpd.2001.108955] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To evaluate the effect of growth hormone treatment on final height, phosphate metabolism, bone markers, and bone mineral density in children with X-linked hypophosphatemic rickets. STUDY DESIGN Six patients (aged 7.8 +/- 1.8 years; height z score, -3.4 +/- 0.5) received conventional treatment (1,25-dihydroxyvitamin D(3) plus phosphate salts) combined with growth hormone (0.6-0.9 IU/kg per week, subcutaneously) (group A); 6 patients (aged 7.9 +/- 2.5 years; height z score, -2.1 +/- 0.6, P <.01 with respect to group A) received only conventional treatment (group B). RESULTS Final height z score significantly improved in group A (-2.4 +/- 0.5, P <.03 with respect to the value at entry), whereas it did not change in group B (-2.8 +/- 0.5, P = NS). At final height, degree of body disproportion was similar between the groups (group A, 1.3 +/- 0.2; group B, 1.2 +/- 0.1; P = NS). Phosphate retention, bone markers, and radial bone mineral density increased only in group A. No adverse effects were observed. CONCLUSIONS In poorly growing patients with X-linked hypophosphatemic rickets, growth hormone therapy combined with conventional treatment improves final height, phosphate retention, and radial bone mineral density, but it does not influence degree of body disproportion.
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Affiliation(s)
- G I Baroncelli
- Endocrine Unit, Division of Pediatrics, Department of Reproductive Medicine and Pediatrics, University of Pisa, Pisa, Italy
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Cameron FJ, Sochett EB, Daneman A, Kooh SW. A trial of growth hormone therapy in well-controlled hypophosphataemic rickets. Clin Endocrinol (Oxf) 1999; 50:577-82. [PMID: 10468922 DOI: 10.1046/j.1365-2265.1999.00680.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE Conventional therapy of hypophosphataemic rickets (HR) with oral phosphate and calcitriol does not always result in normal linear growth. Recombinant human growth hormone (rhGH) offers theoretical advantages as an adjunctive therapy. We aimed to determine the effects of adjunctive rhGH therapy in children with well-controlled HR. PATIENTS In this report, 5 prepubertal children (aged 3.5-10.9 years) with well-controlled HR on conventional therapy were given adjunctive standard dose rhGH therapy for one year. DESIGN AND MEASUREMENTS Height, growth velocity, metabolic markers of calcium and phosphate metabolism, body composition, bone mineral density, wrist and knee X-rays, and renal sonography were assessed at regular intervals. Height and growth velocities were also calculated 12 months after ceasing rhGH therapy. RESULTS After 12 months therapy with rhGH, no significant biochemical or radiological benefits were observed. A significant increase in height SD score was observed (P = 0.023), but this was not associated with any increase in the growth velocity SD score and appears to have been due to catch-up growth caused by conventional therapy alone. When rhGH therapy was ceased, no significant decreases in mean height SD or growth velocity SD scores were observed. CONCLUSIONS In well-controlled hypophosphataemic rickets patients receiving conventional therapy, adjunctive therapy with standard dose rhGH offers no benefits in linear growth or rachitic disease markers.
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Affiliation(s)
- F J Cameron
- Division of Endocrinology, University of Toronto, Hospital for Sick Children, Ontario, Canada
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Patzer L, van't Hoff W, Dillon MJ. X-linked hypophosphataemic rickets: Recognition, treatment and prognosis. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0957-5839(98)80055-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Seikaly MG, Brown R, Baum M. The effect of recombinant human growth hormone in children with X-linked hypophosphatemia. Pediatrics 1997; 100:879-84. [PMID: 9346990 DOI: 10.1542/peds.100.5.879] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND X-linked hypophosphatemia (XLH) is characterized clinically by rickets and growth retardation. Conventional treatment of XLH with oral phosphate and vitamin D fails to normalize linear growth. Objective. To determine the benefit and the potential side effects of recombinant human growth hormone (rhGH) therapy in patients with XLH. DESIGN AND METHODS A randomized, double-blind, crossover study was performed throughout a 24-month period in five children with XLH, each patient serving as his own control. The effect of 12 months of rhGH therapy on height, mineral metabolism, glucose and lipid metabolism, hemoglobin, thyroid and parathyroid function, serum 1,25-(OH)2 vitamin D, osteocalcin, growth hormone, urinary calcium, phosphate, nephrocalcinosis, renal function, and bone density was compared with the effects of 12 months of placebo administration on the same parameters. RESULTS The average age (mean +/- SEM) of the patients at the start of the study was 5.6 +/- 1.4 years. Growth hormone therapy improved the height standard deviation score (z-score) from a baseline of -2.66 +/- 0.21 to -2.02 +/- 0.25 and to -1.46 +/- 0.28, after 3 and 12 months, respectively. At the start of the control period the height z-score was -2.27 +/- 0.30 compared with -2.22 +/- 0.16 after 12 months of placebo administration. The growth velocity standard deviation score was -1. 90 +/- 0.40 during the 12 months of placebo administration and +4.04 +/- 1.50 during the 12 months of rhGH therapy. An increase in serum phosphate from 0.88 +/- 0.07 mmol/L to 1.17 +/- 0.14 mmol/L and tubular maximum for phosphate reabsorption (TmP/GFR) from 2.12 +/- 0. 15 to 3.41 +/- 0.25 mg/dL, was observed after 3 months of rhGH therapy. However, both serum phosphate and TmP/GFR were unchanged from baseline after 6, 9, and 12 months of rhGH therapy. Neither serum phosphate nor TmP/GFR changed from baseline during the placebo administration. Insulin-like growth factor 1 (IGF-1) increased from 114 +/- 25 to 354 +/- 51 ng/mL after 12 months of rhGH therapy. Despite the increase in IGF-1 after rhGH therapy, the value did not exceed normal serum concentration. IGF-1 did not change from baseline after 12 months of placebo administration. Neither therapy with rhGH nor with placebo had an effect on glucose and lipid metabolism, hemoglobin, thyroid and parathyroid function, serum 1, 25-(OH)2 vitamin D, alkaline phosphatase, osteocalcin, urinary calcium excretion, the grade of nephrocalcinosis, glomerular filtration rate, or urinary albumin excretion. Twelve months of rhGH therapy increased bone mass and width but not density. Twelve months of placebo administration had no effect on bone mass, width, or density. CONCLUSION Patients with XLH have an improvement in linear growth and a transient increase in serum phosphate attributable to a transient decrease in urinary phosphate excretion when treated with rhGH.
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Affiliation(s)
- M G Seikaly
- University of Texas Southwestern Medical Center, Dallas, Texas 75235-9063, USA
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