Barakat syndrome: clinical case

Background. Barakat syndrome (HDR syndrome, Hypoparathyroidism, Deafness, Renal dysplasia syndrome, OMIM 146255) is a hereditary disease characterized by hypoparathyroidism, hearing loss and renal disease. The syndrome was first described by the American doctor A. J. Barakat in 1977: two siblings aged 5 and 8 years had steroidresistant nephropathy, hearing loss and hypoparathyroidism. Barakat syndrome is an rare disease: just over 190 cases have been described worldwide. In addition to the three main components, a number of other manifestations of the disease have also been described in patients with Barakat syndrome: disruption of the endocrine and reproductive systems, pathology of the nervous system, congenital heart defects and facial skull malformations, and retinitis pigmentosa. Results. This article presents a clinical case of Barakat syndrome in a 15-year-old boy. The patient was diagnosed with hypoparathyroidism and sensorineural hearing loss. The first signs of hypoparathyroidism appeared at the age of 4.5 years as a seizure syndrome, but at that time the patient was diagnosed with epilepsy, and hypoparathyroidism was diagnosed only at the age of 13 years. Epilepsy was subsequently ruled out. Hearing loss was also diagnosed at age 12. At the time of the last examination, there was no evidence of renal disease or other possible manifestations of the syndrome. The diagnosis was confirmed by genetic tast: previously undescribed probably pathogenic variant of nucleotide sequence HG38, chr10:8058622C>T, c.559C>T, p.Gln187Ter in exon 3 of the GATA3 gene was found.

Conclusion. The purpose of this article is to inform pediatricians about a rare disease to improve the diagnosis of the syndrome. Also, the description of this clinical case will help to supplement the knowledge on peculiarities of the course of Barakat syndrome.

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