ESPE Abstracts

Background: Hypophosphatemic rickets (HR) is most commonly X-linked or autosomal dominant, but autosomal recessive (AR) forms have been described. ARHR1 (DMP1) and ARHR2 (ENPP1) share identical biochemical characteristics of excessive renal phosphate wasting due to increased circulating levels of the phosphatonin FGF23 and low serum levels of 1,25(OH)2D. By contrast, in hereditary hypophosphatemic rickets with hypercalciuria (HHRH) phosphaturia is ...

Background: Hypoparathyroidism may manifest either as an isolated disorder or as a component of a more complex syndrome. Molecular genetic studies indicate that mutations in PTH, CASR, GCM2 and GNA11 are causes of isolated hypoparathyroidism (IH) and mutations in GATA3, TBCE, FAM111A, AIRE and TBX1 are associated with different complex syndromes with hypoparathyroidism.Objec...

Background: A total of 456 skeletal dysplasias have been classified by molecular, biochemical and/or radiological criteria, into 40 groups. Despite this, the precise, final diagnosis is often difficult due to the high phenotypic and genotypic variability.Objective: To improve the molecular and clinical diagnosis of skeletal dysplasias using a custom-designed next-generation sequencing (NGS) panel.Method: A total of 56 skeletal dysp...

Background: Hypophosphatasia (HPP) is the rare inherited metabolic disorder resulting from loss-of-function mutation(s) in the tissue-nonspecific alkaline phosphatase (TNSALP) gene. TNSALP deficiency can cause a spectrum of complications in children including premature deciduous tooth loss, rickets, poor growth, and compromised physical function. We previously reported that children, 5–12 years old, with HPP and treated with asfotase alfa, a recombinant bone-targeted huma...

Background: Folate and cobalamin are needed for synthesis of methionine, a substrate of methylation in epigenetic, and epigenomic pathways. Methyl donor deficiency (MDD) leads to hyperhomocysteinemia, which has been related to osteoporosis in humans and disruption of epiphyseal cartilage and bone development in rodents. Recent studies have revealed evidence for association between 25(OH)D3 and homocysteine levels, however, underlying mechanisms remain elusive.<p...

Background: In-vivo skeletal MRI imaging remains challenging due to the extremely short MR relaxation times (<1 ms) of protons bound to water in bone. However, each MRI sequence contains properties identifiable through feature-based recognition, highlighting characteristics relating to skeletal configuration. We thus present a novel statistical method for clinical 1.5 Tesla (T) MRI in quantifying trabecular microstructure and use HRpQCT to determine its accuracy.<...