hrp0092p1-307 | Adrenals and HPA Axis (2) | ESPE2019

"CAH-X" Due to Homozygous Deletions of CYP21A2 and TNXB Exon 35 in a Newborn from the 17 OHP Screening

Stoeva Iva , Mihova Kalina , Georgieva Raliza , Vlahova Diana , Diankova Diana , Dimitrova-Dasheva Anna , Pramatarova Tania , Kaneva Radka

The CYP21A2 and the TNXB genes are highly homologous with their corresponding pseudogenes (CYP21A1P and TNXA), leading to frequent homologous recombination. The TNXB includes 43 exons, the mRNA encodes tenascin-X (TNX), an extracellular matrix glycoprotein, highly expressed in connective tissue.CAH patients with a "contiguous gene syndrome" comprising a deletion of both genes- CYP21A2 and TNXB have been described. Chimeric genes generated by larg...

hrp0092p3-46 | Bone, Growth Plate and Mineral Metabolism | ESPE2019

Growth Hormone Treatment of a Patient with X-Linked Hypophosphatemic Rickets Caused by PHEX Mutation: Effects on Linear Growth

Rojek Aleksandra , Obara-Moszynska Monika , Niedziela Marek

Background: Hypophosphatemic rickets (HR) stands for a heterogenous group of rare disorders in which excessive renal phosphate wasting is observed. The main characteristics of X-linked HR (XLHR) (OMIM #307800) caused by mutation in PHEX (phosphate-regulating endopeptidase) gene (OMIM *300550) include bone deformities, disproportionately short stature, dental anomalies and hypophosphatemia with coexisting low renal phosphate reabsorption. The patie...

hrp0089p3-p022 | Adrenals and HPA Axis P3 | ESPE2018

Identification of X-linked Adrenoleukodystrophy in Boys Presenting with Adrenal Insufficiency in the Absence of Adrenal Antibodies

Ryalls Michael , Gan Hoong-Wei , Biedenkapp Joe , Davison James

Adrenoleukodystrophy (ALD) is an X-linked, metabolic disorder caused by genetic deficiency of peroxisomal ALD protein resulting in accumulation of very-long chain fatty acids (VLCFA) primarily in the adrenal cortex and central nervous system. Approximately 35–40% of boys with ALD develop cerebral ALD (CALD), which causes rapidly progressive cerebral demyelination, loss of neurologic function, and death. Disease progress can be halted by allogeneic hematopoietic cell trans...

hrp0089p3-p031 | Bone, Growth Plate & Mineral Metabolism P3 | ESPE2018

Growth Hormone Treatment of 2 Patients with X-linked Hypophosphatemic Rickets Caused by PHEX Mutation: Effects on Linear Growth

Rojek Aleksandra , Obara-Moszynska Monika , Niedziela Marek

Background: Hypophosphatemic rickets (HR) is a group of rare disorders caused by an excessive renal phosphate wasting. X-linked HR (XLHR) is caused by mutation in PHEX (phosphate-regulating endopeptidase) gene and is characterized mainly by bone deformities, disproportionately short stature, dental anomalies and hypophosphatemia with coexisting low renal phosphate reabsorption. Early treatment with vitamin D and phosphate improves the patient’s growth. Recombinan...

hrp0097fc2.4 | Bone, Growth Plate and Mineral Metabolism | ESPE2023

A real-world study in Germany and Switzerland regarding renal health in children with X-linked hypophosphatemia

Böckmann Ineke , Leifheit-Nestler Maren , John Ulrike , Metzing Oliver , Rehberg Mirko , Peter Schlingmann Karl , Kemper Markus , Patzer Ludwig , Weitz Marcus , Wühl Elke , Freiberg Clemens , Sparta Giuseppina , Hiort Olaf , Schnabel Dirk , Hoppe Bernd , Haffner Dieter

Purpose: X-linked hypophosphatemia (XLH) is the most common hereditary cause of hypophosphatemic rickets. Elevated circulating levels of fibroblast growth factor 23 (FGF23) caused by mutations in the PHEX gene lead to renal phosphate wasting and rickets. Conventional treatment with phosphate salts and active vitamin D is associated with nephrocalcinosis in XLH patients. Mice on a high phosphate diet develop proximal tubular injury. Detailed analysis on kidney ...

hrp0097rfc2.3 | Bone, Growth Plate and Mineral Metabolism | ESPE2023

High incidence of Chiari type I anomalies on MRI in young patients with X-linked hypophosphatemic rickets (XLHR)

Rothenbuhler Anya , Parpaleix Alexandre , Debza Yahya , Adamsbaum Catherine , Linglart Agnès , Ertl Diana-Alexandra , Di Rocco Federico

Background: X-linked hypophosphatemic rickets (XLHR) represents the most common form of genetic hypophosphatemia. Even though skull and cranio-vertebral anomalies of potential neurosurgical interest are observed in children with XLHR, their actual incidence and characteristics are not well established. We aimed to analyze the incidence of Chiari type I anomalies in children with XLHRMethods and materials: Our retrospecti...

hrp0092fc2.3 | Bone, Growth Plate and Mineral Metabolism Session 1 | ESPE2019

Higher Dose of Burosumab is Needed for Treatment of Children with Severe Forms of X-Linked Hypophosphatemia

Zhukouskaya Volha , Audrain Christelle , Lambert Anne-Sophie , Kamenicky Peter , Adamsbaum Catherine , Nevoux Jerome , Chaussain Catherine , Wicart Philippe , Briot Karine , Di Rocco Federico , Colao Annamaria , Di Somma Carolina , Trabado Séverine , Prié Dominique , Rothenbuhler Anya , Linglart Agnès

Background/Aim: X-linked hypophosphatemia (XLH) is a rare disease caused by mutations in PHEX, leading to elevated FGF23 levels, hypophosphatemia and chronic renal phosphate wasting. Burosumab is a monoclonal antibody against anti-FGF23, which has been recently approved for treatment of XLH. Beyond clinical trials, little is known about its efficacy/safety in clinical practice which is the aim of study.Patients/Methods: ...

hrp0092p1-21 | Bone, Growth Plate and Mineral Metabolism | ESPE2019

Dual X-ray Absorptiometry in Children With Hypophosphatasia Treated with Asfotase Alfa: A Pooled Post Hoc Analysis

Simmons Jill H. , Rush Eric T. , Petryk Anna , Zhou Shanggen , Martos-Moreno Gabriel Á.

Hypophosphatasia (HPP) is a rare, inherited, systemic disease characterized by deficient tissue-nonspecific alkaline phosphatase activity. Common manifestations in children include impaired skeletal mineralization, short stature, and reduced physical function. Asfotase alfa is an enzyme replacement therapy approved for treatment of patients of any age with pediatric-onset HPP. The utility of dual X-ray absorptiometry (DXA) as a diagnostic tool or measure of treatment effective...

hrp0092p3-270 | Late Breaking Abstracts | ESPE2019

A Real World, Clinical Experience of Burosumab Therapy in a Cohort of Children with X-Linked Hypophosphataemia

Sandy Jessica , Gilbey-Cross Robyn , Santos Rui , Cocca Alessandra , Sakka Sophia , Morris Mavali , Massey Jill , Cheung Moira

Burosumab, a monoclonal antibody targeting fibroblast growth factor 23, is now available for clinical use in children with X-linked hypophosphatemia (XLH). We explored the effects of this treatment in a clinical setting, considering biochemistry, growth, deformity, functionality, quality of life, pain and fatigue.Methods: Clinical, biochemical, radiological and questionnaire data were reviewed at 6 and 12 months in a cohort of 8 children...

hrp0089fc14.5 | Multisystem Endocrine Disorders | ESPE2018

Pubertal Females Produce an Enhanced Interferon-Alpha, Anti-viral Response Compared to Males, Which is Associated with X Chromosome Number, and Not Sex Hormones

Webb Kate , Butler Gary , Ciurtin Coziana , Peckham Hannah , Radziszewska Anna , Wedderburn Lucy R , Ioannou John

Introduction: Very little is known about the development of the immune system during puberty. Autoimmune diseases, like juvenile onset systemic lupus erythematosus (jSLE), have an unexplained female bias and a higher incidence after puberty. IFN alpha (IFNα) is a potent antiviral cytokine, and jSLE has a strong IFNα transcriptional signature. Toll like receptors 7 and 9 (TLR7/9) sense viral RNA and DNA respectively, and trigger plasmacytoid dendritic cells (pDC) to p...