The effect of neutrophil/lymphocyte ratio (NLR) in predicting the risk of development of ureteral stricture after ureterorenoscopy

Objective: We aimed to determine the usefulness of Neutrophil/Lymphocyte ratio (NLR) and Platelet/Lymphocyte ratio (PLR) in predicting the risk of ureteral stenosis and difficult ureter development due to ureteral inflammation and fibrosis in patients with a history of endoscopic upper urinary system surgery. Materials and Methods: Between April 2022 and April 2023, a total of 130 patients with a history of endoscopic upper urinary tract surgery and ureteral instrumentation participated in the study. The study group was divided into two groups consisting 65 patients in each who developed ureteral stricture or difficult ureter after endoscopic upper urinary system surgery (Group 1) and who did not develop (Group 2). Surgeries were performed by experienced urologists, and ureteral stenosis and difficult ureter fixation were defined under endoscopic direct visualization or RGP application peroperatively. Preoperative history and routine blood analyses of both groups were evaluated, and the characteristics of prior endoscopic surgery were compared with NLR and PLR. Results: While the rate of hydronephrosis was 67,7% in patients in group 1, it was 50,8% in patients in group 2. A statistically significant difference was found comparing of the presence of hydronephrosis between the groups (p: 0.050). While the rate of stone removal history was 52,3% in patients in group 1, this was 20% in patients in group 2. A statistically significant difference was found regarding of the presence of a history of stone removal between the groups (p< 0.001). While the NLR value of the patients in group 1 was 2,62 , the NLR value of the patients in group 2 was 2,29. No statistically significant difference was found in comparison of NLR between groups (p: 0.139). While the PLR value of patients in group 1 was 136,57 , the PLR value of patients in group 2 was 118,66. No statistically significant difference was noted in comparison of PLR between groups (p: 0.076). Conclusion: Although NLR and PLR, which are considered to be associated with inflammation and fibrosis, were higher in the group with ureteral stenosis and difficult ureter, we were unable to detect a statistically significant difference between the groups. In order to reveal this relationship, further studies with larger numbers of patients are needed. Keywords: ureteral stricture, difficult ureter, neutrophil/lymphocyte ratio