Chronic kidney disease is the outcome of progressive chronic kidney diseases. Chronic kidney disease has a special social significance, affecting the quality of life and life expectancy and life expectancy. Early detection of children and adolescents with chronic kidney diseases and early stages of chronic kidney disease will not only slow down the progression, but also prevent the loss of kidney function. The article presents the main pathogenetic factors influencing the formation and progression of tubulointerstitial fibrosis — arterial hypertension with impaired general and local renal hemodynamics, proteinuria, ischemia, impaired normal functioning of the endothelial barrier, molecular genetic markers; the role of mast cells in the pathogenesis of renal fibrosis, nephrosclerosis. © 2025 Elsevier B.V., All rights reserved.