Glomerulonephritis (GN) is a group of diseases with immune-inflammatory damage to the glomeruli (Sethi S., 2012; Kronbichler A. et al., 2015; Couser W.G., 2016). The classical representative of the GN group is postinfectious GN (PIGN), which can have both acute and chronic courses. In 1/3 of cases, acute PIGN progresses to a chronic form. Chronic GN is a progressively worsening disease, and cases of recovery are rare. In countries with high socio-economic development, chronic GN ranks third among causes of chronic kidney disease (CKD), while in some Asian and African countries, it is the leading cause due to the high prevalence of infectious diseases and lack of conditions for effective treatment of diseases contributing to the development of GN (Ayodele O.E., Alebiosu C.O., 2010; Jha V. et al., 2013). In Uzbekistan, GN is a leading cause of terminal chronic renal failure, which is incompatible with life and requires expensive renal replacement therapy (dialysis, kidney transplantation) (Bikbov B.T., Tomilina N.A., 2016). Currently, for establishing the clinical course—acute and chronic GN—clinico-anamnestic data, general laboratory tests, blood and urine biochemical studies, radiological methods, and determination of glomerular filtration rate (GFR) are used (Mukhin N.A. et al., 2011).However, in clinical practice, there are often difficulties in the timely differentiation between acute GN and the exacerbation of chronic GN at the early stages of the disease due to the lack of specific diagnostic criteria. Chronic GN is usually diagnosed when significant, irreversible damage to the kidneys has already occurred with the development of nephrosclerosis, and the opportunity for timely diagnosis and treatment, which could prevent the progression of the pathological process in the kidneys, has been missed.