FAMILIAL CASE OF AUTOSOMAL DOMINANT HYPOCALCEMIA

Autosomal dominant hypocalcemia (ADH), or familial hypocalciuric hypercalcemia (FHH) is a rare hereditary disease manifested by hypocalcemia and hypercalciuria due to a malfunction of the calcium-sensitive receptor (mutations in the CASR or GNA11 genes). A familial clinical case of ADH is presented: the disease was diagnosed in a 36 y/o female and her two male children of 11 and 1.5 y/o. The disease was detected in an older child aged 7 years on the basis of convulsive syndrome, decreased blood calcium and parathyroid hormone, increased calciuria and detection of a mutation in the CASR gene (c.344-358del TTGCTCAAAACAAAA/ p.116 120delAQNKI). The initial manifestations of the disease in the form of a convulsive syndrome were observed in a child starting his 2nd day of life and were regarded as a manifestation of epilepsy, which was then followed by a long non-convulsive period. The patient needs constant therapy with alfacalcidol and has nephrocalcinosis. Based on the diagnosis made, the disease was also confirmed in his mother as the asymptomatic hypocalcemia and a mutation in the CASR gene were found. The woman does not need drug therapy, does not have nephrocalcinosis. In the youngest child, the diagnosis was suspected at birth on the basis of convulsions, hypocalcemia and was subsequently confirmed then by the detection of a mutation in the CASR gene. The course of the disease in the youngest child is severe, aggravated by the presence of perinatal CNS lesions and epilepsy. The patient has been receiving therapy with alfacalcidol since birth, has manifestations of severe nephrocalcinosis with a decrease in the filtration function of the kidneys. To stop the convulsive syndrome the patient needs to maintain a higher level of blood calcium, which is complicated due to hypercalciuria and causes chronic kidney disease. Conclusion: the observed familial case demonstrates the polymorphism of the course of the disease, and, given the rarity of the disease and the nonspecificity of manifestations, the description of this case will improve the awareness of medical practitioners of various specialties about the disease for its timely diagnosis.