Introduction. About 200 thousand operations for urolithiasis are performed annually in Russia, but the frequency of postoperative complications reaches 30%. Infectious complications occur with a frequency of up to 40% in the form of various forms of pyelonephritis, urosepsis is recorded in 3% of patients.
The aim of the study determine the intensity of blebbing of the plasma membrane of lymphocytes in infectious complications of urolithiasis.
Materials and methods. A prospective study examined 1,240 patients with urolithiasis. Inflammatory complications were characterized by the development of bacteriuria, serous pyelonephritis, purulent pyelonephritis and urosepsis. Complications of infectious nature were characterized by the development of bacteriuria, serous pyelonephritis, purulent pyelonephritis and urosepsis. During the study, complications of an infectious nature were detected in 148 patients, which amounted to 11,93% of cases. The control group consisted of - 25 persons with urolithiasis and a favorable course of the postoperative period. Lymphocyte membrane condition was evaluated by phase contrast microscopy.
Results. Changes in plasma membrane structure were more frequently reported in patients with postoperative purulent pyelonephritis and urosepsis. When assessing the presence of circulating microparticles, the highest number was recorded in patients with urolithiasis complicated by purulent pyelonephritis or urosepsis - 1318 [982; 2007] and 1531 [1028; 1963], respectively. A relationship was established between the degree of severity of terminal blebbing of the plasma membrane of lymphocytes and the nature of inflammatory complications in urolithiasis.

Keywords: Urolytis, blebbing, lymphocyte, urosepsis, pyelonephritis