Comparative study of morphological changes in the kidney and ureter of a rabbit with various methods of infection

Introduction. There are two main routes of urinary tract infection: ascending and hematogenous. In the ascending route, the infectious agent penetrates from the external environment through the external openings of the urinary organs. The role of bacterial translocation in the development of the inflammatory process in the urinary organs is still poorly understood. Materials and methods. We conducted an experiment on rabbits (n=45) and studied the structural changes in the kidneys and ureter depending on the pathogenesis of acute pyelonephritis. The animals were randomly divided into 5 groups: 2 experimental and 3 control. In experimental groups I and II , we modeled obstructive pyelonephritis by ligation of the ureter. In control groups III and IV, an infectious agent was administered similarly to that in the experimental groups, but without creating a model of obstructive pyelonephritis. In control group V, a laparotomy was performed without ligation of the ureter and without injection of bacteria. The morphological study was carried out with optical microscopy. Results. In group I, on day 3, the inflammatory infiltration was detected in 80% of cases and on day 5, in 100%. In group II , on days 3 and 5, the inflammatory process in the ureteral tissue developed in all cases. There were no morphological changes in the kidneys and ureter in groups III and V. In group IV, on days 3 and 5, the frequency of inflammatory infiltration was 80%. Conclusion. The nature of morphological changes in the kidneys and ureter in acute pyelonephritis depends on both the ways of infection and the timing of ureteral obstruction. In enterorenal translocation, the severity of morphological changes occurs later. Keywords: urinary tract obstruction, acute pyelonephritis, intestinal translocation, ascending infection