UTIs are more likely to occur in patients with Ureteral Stents. Therefore, antibiotics should be administered prophylactically before stent placement and removal. The ureteral stent acts as a foreign body and therefore bacteria often colonise them, usually within the first 2 weeks after stent placement. Patients with permanent stents have a 100% colonisation rate of the ureteral stent, compared to 69.3% of patients with temporary stents. Unfortunately, patients with asymptomatic bacteriuria do not benefit from long-term therapy.
Additionally, diabetes mellitus, chronic renal failure and pregnancy were associated with a higher risk of stent related bacteriuria. The process of Ureteral Stents associated UTI, stent encrustation, and SRS has been linked to biofilm formation on the stent surface as a crucial step. The role of biofilms on stent morbidity has been considered controversially. Inside this biofilm, microbes are protected from host defences and antibiotics, which may contribute to an accelerated development of antibiotic resistance.