Abstract:
Over the past decades, there has been an increase in the number of diseases of the urinary system in the world. Kidney diseases often acquire a long, progressive course with an outcome in chronic renal failure (CRF). An important feature of nephrological diseases is their propensity for
progressive development. According to the latest data on the patterns of chronicity of kidney damage, the end result of a number of renal and non-renal diseases is the development of chronic kidney disease (CKD). The term "CKD" is known to have been coined by the American Association of Nephrologists in 2002. The criteria for determining CKD are: kidney damage lasting more than 3 months, which manifests itself in the form of structural or functional disorders of the organ's activity, with or without a decrease in the glomerular filtration rate (GFR) less than 60 ml per minute
per 1.73 m2 in the presence or absence of other signs damage. Given the complex mechanism of GFR changes under physiological
conditions, especially in pathology, it becomes necessary to measure filtration in active nephrons, as well as the total number of functioning nephrons. The only way to solve such problems today is to determine the functional renal reserve (FRR). It is important to note that the determination of GFR under conditions of relative functional rest is not sufficient in diagnosis, indicating only its overall value at the time of the study that is, about basal GFR, and does not always make it possible to correlate this indicator with the total number (mass) of nephrons which is
especially important.