A.I. ALMUKHAMETOVA, N.L. MATSAK, A.N. MAKSUDOVA

 Kazan State Medical University, Kazan, Russia

Contact details:

Matsak N.L. — resident doctor of the Department of Hospital Therapy

Address: 49 Butlerov St., 420012 Kazan, Russian Federation, tel.: +7-951-201-45-24, e-mail: nikitamatzak@yandex.ru

To date, there are no specific criteria for the diagnosis of CKD in elderly patients. According to the results of many studies, it is noted that current methods of GFR calculation (CKD-EPI) do not reflect the true change in renal function, while ultrasound changes associated with physiologic aging (kidney size, parenchyma, blood flow parameters) can be interpreted as chronic kidney disease. Currently, new methods of GFR assessment are actively searched to more accurately estimate the function in the elderly, taking into account the characteristics of physiologic aging. This review provides current data on the physiology of renal aging: reduction in organ size unrelated to chronic kidney disease, thinning of the cortical layer, and decreased blood flow and filtration. Information on methods of investigation of renal function and structure is presented; methods for GFR calculation (BIS1, FASCr, EKFC) are reviewed. None of the equations is universal, but the EKFC equation showed accurate estimated filtration rate. Ultrasound changes of kidneys in people over 60 years of age are as follows: a decrease in cortical layer thickness, size, volume of renal tissue, and an increase in resistivity index. Thus, it is necessary to adapt the criteria for the CKD diagnosis in the elderly, namely, eGFR and renal ultrasound changes, taking into account normal physiologic aging.

Key words: CKD in the elderly, glomerular filtration rate estimate, physiological aging of the kidneys, ultrasound of the kidneys in the elderly, kidney function in the elderly.

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