ESPE Abstracts

Introduction: Despite the high detection rate of GNAS molecular defects, about 30% of patients with a clinical suspect of PHP/AHO still lack a confirming molecular diagnosis. Mutations in genes encoding proteins crucial for cAMP-mediated signaling have been recently detected in a small subset of patients negative for GNAS defects, showing a phenotypic overlap between PHP and Acrodysostosis.Clinical case pres...

Background: Genetic and epigenetic alterations at the GNAS locus are responsible for the Gsα protein dysfunctions causing Pseudohypoparathyroidism (PHP), a heterogeneous disease characterized by multiple hormone resistances and AHO signs (short stature, obesity, round face, brachydactyly, subcutaneous ossifications and mental retardation). A clinical overlap among molecular subtypes of the disease (Ia, Ib, Ic and II) makes the current classification inadequate; furthermor...

Since the first description of pseudohypoparathyroidism (PHP), a remarkable clinical variability, which translates in several PHP subtypes, was observed. In 2016 a new classification of this group of diseases have been published by the European Network on PHP and related disorders, proposing “inactivating PTH/PTHrP signaling disorder” (iPPSD) as a new term that encompasses all the clinical entities, stressing the common mechanism responsible for all diseases. iPPSDs ...

Background: Pseudohypoparathyroidism type 1A (PHP1A) and PseudoPHP are caused respectively by maternal and paternal mutations involving those GNAS exons that encode the alpha-subunit of the stimulatory G protein (Gsα). Common to different forms of PHP1B is a loss-of-methylation (LOM) at one or several maternal GNAS exons, which likely reduces Gsα expression in certain tissues. In most autosomal dominant PHP1B variants (AD-PHP1B), LOM is restricted t...

Background: Sporadic pseudohypoparathyroidism type Ib (spor-PHP-Ib) is caused by GNAS methylation alterations with loss of imprinting at the exon A/B differentially methylated region (DMR), without genetic deletions disrupting the STX16 ICR. These patients classically display hormone resistance limited to PTH and TSH with no Albright hereditary osteodistrophy (AHO).Objective and hypotheses: We describe two cases with the same imprinting methylat...

Classic features of inactivating PTH/PTHrP Signaling Disorder 2 or 3 (iPPSD2, iPPSD3), i.e. former pseudohypoparathyroidism include multi-hormone resistance, short stature, subcutaneous ossifications, brachydactyly, and early-onset obesity and a molecular defect at the GNAS region. In addition, patients may present with less-known features including craniosynostosis (CSO).Objective: To describe the prevalence of CSO in a cohort ...

Background: Disorders related to an impairment in parathyroid hormone (PTH) signaling pathway are historically classified under the term pseudohypoparathyroidism (PHP), that now encompasses rare, related but highly heterogeneous diseases with demonstrated (epi)genetic causes. The actual classification is based on the presence or absence of specific clinical and biochemical signs together with an in vivo response to exogenous PTH and an in vitro assay of Gs&#9...

Pseudohypoparathyroidism (PHP) and related disorders lead to a wide spectrum of abnormal physical characteristics, neurocognitive and endocrine abnormalities. PHP (including all subtypes), pseudoPHP, acrodysostosis and progressive osseous heteroplasia refer to heterogeneous disorders characterized by physical findings, differently associated in each subtype, including short bones, short stature, stocky build, subcutaneous ectopic ossifications, as well as laboratory abnormalit...

Background: The annual worldwide incidence of childhood adrenocortical tumors (ACT) ranges from 0.3 to 0.38/million children below the age of 15 years. Only 1–2% of them are feminizing ACT occurring in prepubertal boys and presenting with gynecomastia that normalizes after tumor removal.Case report: We present a case of a feminizing ACT. The boy was referred for bilateral gynecomastia, appeared 6 months before, at the chronological age (CA) of 7.5 y...

Background: Klippel–Feil syndrome (KFS) is characterized by congenital fusion of cervical vertebrae and has a prevalence of 1:50 000. The phenotypic expression is variable, sometimes presenting with extraskeletal symptoms.Case report: A girl was referred at the cronological age (CA) of 10.3 years with a suspected diagnosis of Turner syndrome, due to the presence of webbed neck and progressive deceleration of growth velocity. The girl, born in Russia...