ESPE Abstracts

Background: Insulin-like growth factor I (IGF-I) is one of the important hormonal mediators of human growth. Circulating IGF-I exists in a ternary complex bound to the acid-labile subunit (ALS) and one of its six binding proteins (BPs). IGF-I bound to ALS and BPs needs to be liberated by either Pregnancy Associated Plasma Protease A (PAPP-A) or A2 (PAPP-A2) to reach its receptor. Stanniocalcin 2 (STC2) is a potent inhibitor of both PAPP-A and PAPP-A2. Genome-wide association s...

Objectives: Vosoritide is a C-type natriuretic peptide analog which binds its receptor on chondrocytes, leading to increased chondrocyte proliferation and differentiation via its inhibition of the ERK1/2-MAPK pathway. It was recently approved for increasing linear growth in children with achondroplasia. This is the first study to examine the safety and efficacy of vosoritide in children with hypochondroplasia.Methods: Th...

2 siblings were referred for evaluation fo short stature and failure to thrive. Both were born of 3rd degree consanguinity, first and second in birth order. the first sibling was 2 1/2 year old at time of referral and had birthweight of 3.1 kg and had gross motor delay. Present height was 65 cm (SDS −6.2 S.D.)and weight was 6 kg (<3rd centile) Second sibling was 1.5 years old, with gross motor delay with height of 57 cm (SDS −6.5 S.D.</sma...

Background: PAPP-A2 (pregnancy-associated plasma protein A2) deficiency, caused by homozygous mutations in the PAPP-A2 gene results in a novel syndrome of significant growth failure. PAPP-A2 cleaves IGF binding proteins 3 and 5, thereby freeing IGF-I from its ternary complex and allowing it to become biologically active. We recently reported the first two families with PAPP-A2 mutations. Response to recombinant human IGF-I (rhIGF-1) in these patients is unknown.<p class="a...

Background: Main features of the autosomal dominant form of GH deficiency (IGHD II) include markedly reduced secretion of GH combined with low concentrations of IGF-I leading to short stature.Objective and hypotheses: We report on a girl referred for assessment of short stature (−4.6 SDS) at a chronological age of 7 yr 10 mo. The GH deficiency was confirmed by standard GH provocation tests, which revealed severely reduced GH and IGF-I concentration...

Background: Familial isolated growth hormone deficiency (IGHD) type II is autosomal dominantly inherited and caused by splice-site mutations and nucleotide substitutions in the GH1 gene. The missense mutation R183H is a well-described genetic variant that causes familial IGHD type II. Individuals with this mutation have releasable GH stores, but GH secretion is severely reduced resulting in short stature.Objective and hypotheses: This study aimed to repo...

Background: Nutritional excess of vitamin A, a precursor for retinoic acid (RA), causes premature epiphyseal fusion, craniosynostosis, as well as light-dependent retinopathy. Similarly, homozygous loss-of-function mutations in one of the major RA-metabolizing enzymes CYP26B1 causes advanced bone age, premature epiphyseal fusion, and craniosynostosis. We studied a patient with markedly accelerated skeletal and dental development, retinal scarring, and autism-spectrum disease.</...

Children with ISS vary in their response to GHT. We conducted a post hoc analysis to identify clinical characteristics associated with very good or poor response during year 1 of GHT in a subset of 1550 GH naïve children with ISS from NordiNet® IOS (NCT00960128) and the ANSWER Program (NCT01009905). We included patients aged 3–11 years (males) or 3–10 years (females) at treatment start, prepubertal throughout year 1 of treatment, with height SDS...

Background: Aggrecan (ACAN) is a proteoglycan found in the extracellular matrix of articular and growth plate cartilage. Animal studies have shown that mutations in the ACAN gene lead to premature hypertrophic chondrocyte maturation, causing accelerated cartilage ossification. Patients with ACAN deficiency present with dominantly inherited short stature, often with advanced skeletal maturation and premature growth cessation, as well as early-onset joint diseas...

Introduction: Hypochondroplasia is a rare genetic growth-related condition primarily caused by FGFR3 variants that lead to decreased endochondral bone growth, disproportionate short stature and other medical complications. It shares pathogenetic and phenotypic similarities to achondroplasia. Outside of Japan, there are no approved pharmacological treatments for hypochondroplasia. Vosoritide, a C-type natriuretic peptide analog, is an approved first-in...