Monotherapy with Fluoroquinolone or Trimethoprim-Sulfamethoxazole for Treatment of Stenotrophomonas maltophilia Infections

Abstract

ABSTRACTThe treatment of choice forStenotrophomonas maltophiliais trimethoprim-sulfamethoxazole (SXT). Fluoroquinolones (FQs) havein vitroactivity againstS. maltophilia; however, there is limited published information on their effectiveness. The purpose of this study is to compare the effectiveness of FQs and SXT for the treatment ofS. maltophilia. A retrospective review of 98 patients withS. maltophiliainfections who received SXT or FQ monotherapy was conducted. Patients ≥18 years old with a positive culture forS. maltophiliaand clinical signs of infection who received treatment for ≥48 h were included. Microbiological cure and clinical response were evaluated at the end of therapy (EOT). In-hospital mortality and isolation of nonsusceptible isolates were also evaluated. Thirty-five patients received SXT, and 63 patients received FQ; 48 patients received levofloxacin, and 15 patients received ciprofloxacin. The most common infection was pulmonary. The overall microbiological cure rate at EOT was 63%. Thirteen of 20 patients (65%) who received SXT and 23 of 37 patients (62%) who received FQ had microbiological cure at EOT (P= 0.832). The overall clinical success rate was 55%, 52% for those who received FQ and 61% for those who received SXT (P= 0.451). In-hospital mortality was 24%, with similar rates in the two groups (25% for FQ versus 22% for SXT;P= 0.546). Development of resistance on repeat culture was 30% for FQ and 20% for SXT (P= 0.426). Fluoroquinolone and SXT monotherapies may be equally effective for the treatment ofS. maltophiliainfections. Resistance was documented in subsequent isolates ofS. maltophiliain both groups.