Introduction. According to the epidemiological studies, prevalence of urolithiasis is nearly 10% worldwide. The course of the disease is often complicated by the development of pyelonephritis, the pathogenesis of which is rather multifactorial. Along with urinary tract obstruction, increasing virulence of microorganisms and immune insufficiency in patients also plays a major role.
Aim. To define specific features of immune insufficiency in patients who develop pyelonephritis as a complication of urolithiasis.
Materials and methods. A total of 150 patients with urolithiasis complicated by pyelonephritis were prospectively enrolled into our study in order to develop a novel method. All patients were divided into two clinical groups. Group I consisted of 75 patients with urolithiasis complicated by serous pyelonephritis and Group II included 75 patients with urolithiasis complicated by purulent pyelonephritis. In all patients an evaluation of the immune status with a determination of CD3, CD4, CD8, CD16, CD19 level and phagocyte activity of immune system was carried out. The state of lymphocytes’ plasmatic membrane was evaluated by phase contrast microscopy.
Results. It is established that development of pyelonephritis in patients with urolithiasis is accompanied by a lymphopenia, the decrease in relative contents T-helpers, natural killers, as well as a decrease in the immuno-regulatory index and an increase in indicators of terminal and total lymphocytes’ blebbing. The most pronounced changes were noted in purulent pyelonephritis, where suppressed immune status was confirmed by the high level of lymphocyte with terminal blebbing state.

Keywords: blebbing, immune status, pyelonephritis, urolithiasis