ESPE Abstracts

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: ...

Background: Studying patients with rare Mendelian diabetes has highlighted molecular mechanisms regulating β-cell pathophysiology. Previous, experimental studies have shown that Class IIa histone deacetylases (HDAC4, 5, 7, and 9) modulate mammalian pancreatic endocrine cell differentiation, function and finally glucose homeostasis.Methods: We performed exome sequencing in one adolescent boy with non-autoimmune di...

Objective: This project aims to evaluate the effect of two isotopically labelled internal standards on the quantification of 17OHP by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) as an orthogonal technique.Methods: Three LC-MS/MS and one GC-MS/MS laboratories, spanning four countries worldwide, who routinely measure serum17OHP, compared two internal ...

Background/Aim: X-linked hypophosphatemia (XLH) is a rare disease caused by inactivating mutations in the phosphate-regulating endopeptidase homolog X-linked (PHEX) gene, characterized by chronic hypophosphatemia. XLH children present with progressive skeletal deformities (leg bowing, waddling gait, poor growth and disproportional short stature), dental abscesses, and craniosynostosis. Most affected children have been treated so far with multiple dail...

Objective: This project aims to evaluate the effect of two isotopically labelled internal standards on the quantification of 17OHP by liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS) as an orthogonal technique.Methods: Three LC-MS/MS and one GC-MS/MS laboratories, spanning four countries worldwide, who routinely measure serum17OHP, compared two internal ...

Background: Hypopituitarism is characterized by deficiency of one or more anterior pituitary hormones. POU1F1 mutations are the second most frequent known cause of combined pituitary hormone deficiency (CPHD). Patients are typically deficient in GH, TSH, and prolactin, although two unrelated cases were reported with isolated GH deficiency (IGHD). To date, all POU1F1 mutations have been reported for the predominantly expressed alpha isoform, which is a transcr...

Background/Objective: Micro-and macrovascular changes are the cause for diabetes complications. Retinal vessel analysis is a unique method to examine microvascular changes in brain derived vessels.Subjects/Methods: Sixty-seven pediatric and adolescent type 1 diabetes patients and 58 healthy control persons underwent nonmydriatic retinal photography of both eyes. Arterioles and venules positioned in the region 0.5 to 1 diameter of the optic disc measured ...

Calcium signaling is fundamental to many cellular processes. An important pathway for increasing intracellular Ca2+ levels is store-operated Ca2+ entry (SOCE) regulated by stromal interaction molecule (STIM1-2), and Ca2+ channels formed by ORAI1-3 proteins. Mutations in the ORAI1 and STIM1 genes that abolish SOCE cause a combined immunodeficiency (CID) syndrome that is accompanied by autoimmunity and nonimmunologic symptoms. We present patients with Anhidrotic Ectodermal Dyspl...

Background: Paediatric HPAT, though generally benign, incurs significant neuro-endocrine morbidity. Their management is unclear and the paediatric neuro-oncology or adult pituitary forum at which they are discussed lack pituitary or age-specific expertise respectively. The UK National HPAT Interest Group has pioneered a monthly, multi-site, interdisciplinary, video conferencing decision-making forum, to garner necessary experience and evidence of outcomes to assist worldwide r...

Background: Mutations in genes involved in insulin secretion or regulation of β cell identity cause both persistent neonatal diabetes (PND) and hyperinsulinemic hypoglycemia of infancy (HHI) pinpointing shared pathogenic mechanisms. KCNQ1 encodes a potassium channel protein, Kv7.1, which is a voltage-gated potassium channel expressed in cardiac tissue, pancreas, inner ear neurons, and other tissues. Variants in or nearby to KCNQ1 were linked t...