Does duration of stenting increase the risk of clinical infection?

Objective: We investigated when an indwelling ureteral catheter should be withdrawn for infection and evaluated the importance of urinary cultures in identifying colonized microorganisms and define the bacterial flora encountered in the study. Moreover, this study tried to determine the clinical role of stent culture in clinical practice.
Materials and methods: The study was conducted between June 2018 and February 2019. Patients with ureteral stent implantation after endoscopic ureteral stone treatment were divided into two groups and each group consisted of 45 patients. Ureteral catheter was removed 15 and 30 days after ureteral stone treatment in group 1 and 2, respectively, and transferred for microbiological examination. The urine culture was obtained before and after ureteral stent implantation. The groups were compared in terms of demographics, urine and catheter cultures results. Urine analysis and catheter culture results were also compared.
Results: Demographic data of patients were similar in both groups. 3 patients in group 1 and 12 patients in group 2 had positive urine culture before catheter retraction; 2 of 45 and 6 of 45 patients had positive catheter culture in group 1 and 2, respectively. Although 2 patients in group 1 and 4 patients in group 2 had urine culture sterile, they had growth in catheter culture. In Group 1, 1 of the microorganisms was E. fecalis and 1 was E. coli. In Group 2, 2 cases were E. fecalis, 3 were E. coli and 1 was MRSE. There was no significant difference between the urine analysis results of the patients before catheter retraction and catheter culture positivity.
Conclusions: Pre-operative urine culture does not exclude catheter colonization, and the prolonged duration of the catheter associated with greater colonization and may be associated urinary tract infection. Ureteral catheter should be removed as early as possible.