Endocrine Abstracts

Introduction: Barakat syndrome is a very rare disease and an uncommon aetiology of hypocalcaemia. Also known as HDR syndrome it is an autosomal dominant disorder characterised by hypoparathyroidism, sensorineural deafness and renal disease.

Clinical case: A 59-year-old Caucasian woman was admitted to our Endocrinology ward in May 2014 due to hypocalcaemia despite being medicated with oral calcium. At 35 years old a diagnosis of hypoparathyroidism was established in another hospital when she presented generalized seizures and cardiac failure. Intracranial basal ganglia calcification where revealed at that time and a diagnosis of hypocalcaemic miocardiopathy was established. At the present admission in our hospital, further history revealed progressive hearing loss for the last 20 years. Laboratory work up: Ca²⁺ 7.7 mg/dl (8.6–10.2 mg/dl), Pi 3.1 mg/dl (2.5–4.5), Mg²⁺ 1.9 mg/dl (1.6–2.3), PTH 1.3 pg/ml (12–88), and creatinine 1.10 mg/dl. Abdominal CT scan showed right kidney hypoplasia. DNA sequence analysis revealed on exon 5 of GATA3 gene a heterozygotic mutation c.1043T>C (p.Leu348Pro) that confirmed the diagnosis of Barakat syndrome. We observed one of the two adult sons and the adult daughter of this patient. Hypocalcaemia due to hypoparathyroidism and neurosensorial bilateral deafness were documented in both. Genetic study of this offspring is in course.

Comments: Barakat syndrome may present a variable phenotype. Renal manifestations are the most heterogeneous and usually determine disease prognosis. This patient has the classical triad. The severity of hypocalcaemia since young age and subsequent irreversible cardiac involvement were determinant for prognosis. Timely diagnosis and appropriate hypocalcaemia treatment are paramount. Genetic screening of relatives takes particular relevance in this context.