Multiple Endocrine Deficiencies are Common in Hypoparathyroidism-Retardation-Dysmorphism Syndrome

Context The rare hypoparathyroidism-retardation-dysmorphism (HRD) syndrome (OMIM #241410) is caused by the mutated tubulin chaperone E (TBCE) gene. This gene encodes a critical protein in the microtubule assembly pathway. Objective To evaluate the endocrine profile of patients with HRD. Methods The study used a retrospective analysis of a large cohort of patients in a single university medical center. Sixty-three patients were diagnosed with HRD during 1990 to 2019; 58 of them had an endocrine evaluation. Main outcome measures We investigated somatic growth parameters, the prevalence of hypoglycemia, growth hormone deficiency, hypothyroidism, hypogonadism, and cortisol deficiency. Results All patients were born small for gestational age, and severe growth retardation was found in all patients with mean height standard deviation score (SDS) of -8.8 (range: -5.1 to -15.1) and weight SDS -18 (range: -5.1 to -61.2). Serum insulin-like growth factor-1 concentrations were very low among the 21 studied patients: -2.32 SDS (range: -0.6 to -2.7). Four out of 14 (28%) investigated patients had growth hormone deficiency, and 55% of patients were hospitalized due to symptomatic hypoglycemia. Adrenal glucocorticoid insufficiency was diagnosed in 22% of those tested. Hypothyroidism was found in 36% of patients. Both hypogonadotrophic and hypergonadotrophic hypogonadism were observed. The main magnetic resonance imaging findings were small anterior pituitary gland, small hippocampus, brain atrophy, thin corpus callosum, Chiari type I malformation, and septo-optic dysplasia. Conclusion Multiple endocrine abnormalities are common in patients with HRD syndrome. Periodic screening of thyroid and adrenal functions is recommended.