Clinical Question: Are amoxicillin-clavulanate and ciprofloxacin equivalent as a three-day treatment for uncomplicated cystitis in women?

Setting: Outpatient (primary care)

Study Design: Randomized controlled trial (single-blinded)

Allocation: Uncertain

Synopsis: Investigators identified 370 women, 18 to 45 years of age, with symptoms of acute uncomplicated cystitis and a positive urine culture for at least 100 colony-forming units of uropathogens per mL. Participants were randomized to receive three days of amoxicillin-clavulanate in a dosage of 500 mg/125 mg twice daily, or ciprofloxacin in a dosage of 250 mg twice daily. Follow-up was available for 98 percent of the women at four months. The authors did not state whether persons assessing outcomes were blinded to treatment group assignment.

Using intention-to-treat analysis, a clinical cure (defined as the absence of persistent or recurrent symptoms) occurred in 77 percent of women treated with ciprofloxacin versus 58 percent of women treated with amoxicillin-clavulanate (number needed to treat = five; 95 percent confidence interval, four to 12). Microbiologic cure, defined as no uropathogens on a follow-up urine culture, also was more common in women treated with ciprof loxacin. Amoxicillin-clavulanate was less effective than ciprofloxacin even when the cystitis was caused by bacterial pathogens sensitive to both drugs.

Bottom Line: Three days of ciprofloxacin is superior to three days of amoxicillin-clavulanate in the treatment of uncomplicated cystitis in women. In areas where resistance is not yet a significant problem, physicians should use less expensive trimethoprim-sulfamethoxazole as a first-line agent. (Level of Evidence: 1b–)