Characteristics of Bacterial Colonization after Indwelling Ureteral Stents in Urinary Stone Patients with Diabetes Mellitus and Chronic Kidney Disease

Background: Placement of ureteral stents has been standard after the endoscopic procedures because it relieves obstruction caused by the stone and facilitates urine drainage. Bacterial colonization in the stent plays an essential role in the pathogenesis of stent-associated infections. The goal of this study was to determine the frequency, type of pathogens, and the significance of risk factors that may affect bacterial colonization of ureteral stents after endourology procedures in urinary stone patients. Methods: Thirty patients underwent percutaneous nephrolithotomy or ureterorenoscopy for renal and ureteric stones were enrolled in this study. Urine specimens were collected for culture examination before stent insertion and on removal. The stents were then removed based on the clinical decision via the cystoscope, and three distal tip segments of the stents were sent for culture examination. Results: Four patients (13.3%) before stent insertion and 11 patients (36.7%) before stent removal had positive urine cultures. Eighteen (60%) stents were positive for the culture. Diabetes mellitus (DM) (P = 0.018) and chronic kidney disease (CKD) (P = 0.040) had a significant difference in increasing the risk of bacterial colonization. Pseudomonas aeruginosa was the most common pathogen isolated from the stent culture. Conclusion: An indwelling ureteral stent carries a significant risk of bacterial colonization both on patients with DM and also CKD. P. aeruginosa appears as the most common bacteria in stent culture due to immunocompromised factors of these patients.