Steroidresistant nephrotic syndrome in a child associated with a mutation in the INF2 gene

Introduction. Nephrotic syndrome (NS) is a disease of the glomeruli that occurs in childhood with a frequency of 12–16 per 100,000. More than 85 % children with NS respond to corticosteroid therapy, approximately 10–15 % remain refractory or later become resistant to them. In 10–30 % of patients with steroid-resistant nephrotic syndrome (SRNS), mutations in the structural genes of podocytes, modifier genes were found, there is also evidence of the formation of circulating antibodies to the structure of podocytes, the influence of environmental factors. Difficulties in the diagnosis and treatment of SRNS are determined by its heterogeneous etiology, the frequent absence of remission with the development of multidrug resistance and the progression of the disease with the formation of end-stage chronic renal failure and the return of NS after kidney transplantation. The aim of the study is to present a clinical case of steroid-resistant nephrotic syndrome with focal segmental glomerulosclerosis associated with the c.1280_1285delCACCCC mutation in the INF2 gene, localized on chromosome 14 in a 15-year-old child. Materials and methods. An analysis of clinical and anamnestic data was used - primary medical documentation (medical history), the results of an objective examination with examination, analysis of laboratory, instrumental diagnostic and molecular genetic methods for studying a child with steroid-resistant nephrotic syndrome. Results and Discussion. The presented clinical case demonstrates the development in a child of SRNS with FSGS associated with a mutation in the structural podocyte gene INF2, which was also detected in a close relative. The course of the disease was characterized by multiple drug resistance. Conclusion. The presented clinical case of the development of FSGS in a child with SRNS demonstrates the importance of morphological verification of the disease in a child, conducting a molecular genetic study not only of the patient himself, but also of his parents to predict the risks of kidney transplantation, the return of NS in the recipient and donor.