Oral ciprofloxacin or trimethoprim reduces bacteriuria after flexible cystoscopy

OBJECTIVE To report a large prospective, pragmatic, double‐blind randomized controlled trial to determine whether oral prophylactic antibiotics reduce the risk of bacteriuria after flexible cystoscopy (FC), as up to 10% of patients develop urinary infection afterwards, with significant morbidity and costs for health services. PATIENTS AND METHODS In all, 2481 patients were recruited into a three‐arm placebo controlled trial and 2083 completed it. Patients were randomly assigned to one of three treatments; (i) placebo; (ii) one oral dose of trimethoprim (200 mg); or (iii) one oral dose of ciprofloxacin (500 mg), each administered 1 h before a FC under local anaesthetic. A mid‐stream urine specimen was taken before and 5 days after FC; significant bacteriuria was defined as a pure growth of >105 colony‐forming units/mL. RESULTS The rate of bacteriuria after FC was reduced from 9% in the placebo group to 5% and 3% in patients receiving trimethoprim and ciprofloxacin prophylaxis, respectively. When rates of bacteriuria before FC were considered the odds of developing bacteriuria after FC relative to baseline were 5, 2 and 0.5 for placebo, trimethoprim and ciprofloxacin, respectively. CONCLUSION This large trial shows clearly that one dose of oral ciprofloxacin significantly reduces bacteriuria after FC.