Nitrofurantoin Versus Comparators in the Treatment of Cystitis due to Extended-Spectrum β-Lactamase-Producing...

The increasing prevalence of extended-spectrum β-lactamase (ESBL)-producing bacteria has limited treatment options for cystitis. The recommendation of nitrofurantoin for treatment is based solely on in vitro studies.

We aimed to evaluate the effectiveness of nitrofurantoin versus comparators in treating cystitis due to ESBL-producing Enterobacterales in the clinical setting.

This was a multicenter retrospective cohort study of afebrile adults with symptomatic cystitis and a urine culture of ≥10⁵ CFU/mL of ESBL-producing organism susceptible to nitrofurantoin and comparator antibiotics. Patients were categorized based on treatment (nitrofurantoin vs comparator). Clinical cure was the primary endpoint. Reinfection and relapse were secondary endpoints.

Of 225 patients, 66 received nitrofurantoin and 159 received a comparator. Carbapenems were the most used comparator (57.2%). Clinical cure rates were not significantly different between the groups in crude (77.3% vs 86.2%; P = 0.101) and regression analyses (adjusted odds ratio [aOR], 0.82; 95% CI, 0.34-1.99). Of 35.4% of nitrofurantoin patients and 66.0% comparators group patients who had follow-up cultures, lower odds of relapse and reinfection were observed with nitrofurantoin, though not statistically significant (aOR, 0.28; 95% CI, 0.07-1.18 and aOR, 0.43 with 95% CI of 0.13-1.43, respectively). However, the inpatient setting was significantly associated with higher odds of relapse (aOR, 8.83; 95% CI, 1.07-72.74; P = 0.043).

Nitrofurantoin was as effective as comparators in treating cystitis due to ESBL-producing Enterobacterales. The inpatient setting was associated with higher odds of relapse. Further larger research trials are needed to validate these findings.