Congenital organic hyperinsulinism. Phenotype spectrum predetermined by ABCC8 gene variants

Congenital hyperinsulinism is a hereditary disease belonging to the orphan group, clinically manifested by the development of persistent hypoglycemia in the neonatal period. Neurological disorders resulting from persistent hypoglycemia, in most cases, are accompanied by dysfunction of the central nervous system, regression and delayed psychomotor and speech development. Congenital hyperinsulinism is characterized by heterogeneity of disease phenotypes, manifested by different severity of hypoglycemic syndrome, metabolic and neurological manifestations, which makes it difficult to verify the diagnosis, dictates the need for a comprehensive examination, including molecular genetic analysis in patients and their families. This allows timely appointment of insulinostatic therapy, thereby reducing the risk of severe neurological and metabolic complications. The article presents a description of three clinical cases of сongenital hyperinsulinism associated with homozygous variants in the ABCC8 gene and an autosomal recessive type of inheritance, which were included in the number of patients previously studied by us with variants in the ABCC8 and KCNJ11 genes. The results of this study were partially published by the authors earlier. The experience of monitoring these patients reflects the importance of early diagnosis of сongenital hyperinsulinism, including the use of molecular genetic testing, the timely administration of insulinostatic therapy, allows an objective assessment of the effectiveness of the treatment, and reduces the risk of developing severe metabolic and neurological complications.