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

Abstract

The treatment of choice for Stenotrophomonas maltophilia is trimethoprim-sulfamethoxazole (SXT). Fluoroquinolones (FQs) have in vitro activity against S. 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 of S. maltophilia. A retrospective review of 98 patients with S. maltophilia infections who received SXT or FQ monotherapy was conducted. Patients >18 years old with a positive culture for S. maltophilia and 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 of S. maltophilia infections. Resistance was documented in subsequent isolates of S. maltophilia in both groups.

Risk Factors and Outcomes of Stenotrophomonas maltophilia Bacteraemia: A Comparison with Bacteraemia Caused by Pseudomonas aeruginosa and Acinetobacter Species

“…Levofloxacin may be an alternative drug to treat SM infection [35]. Recent studies indicated that levofloxacin was not inferior to TMP-SMZ for the treatment of SM infection or bacteraemia [36], [37]. However, rapid resistance to fluoroquinolones has been observed in vitro and in vivo [2].…”

Whole-Genome Sequencing Identifies Emergence of a Quinolone Resistance Mutation in a Case of Stenotrophomonas maltophilia Bacteremia

“…SXT resistance in S. maltophilia is not known to be caused by efflux systems but has been linked to class 1 integrons and ISCR elements (1). This suggests that spontaneous resistance is less likely to emerge with SXT monotherapy, although a clinical trial comparing the two antibiotics is warranted (21,22).…”

“…Since resistance from a single SNV emerged during a short course of ciprofloxacin, clinicians should be cautioned about using quinolone monotherapy for S. maltophilia bacteremia, as highlighted in recent retrospective studies (21,22). The wide variety of MDR phenotypes and unreliability of DST results have created uncertainty about appropriate treatment for S. maltophilia, but SXT remains the most common choice for monotherapy (1,21,22).…”

“…The wide variety of MDR phenotypes and unreliability of DST results have created uncertainty about appropriate treatment for S. maltophilia, but SXT remains the most common choice for monotherapy (1,21,22). SXT resistance in S. maltophilia is not known to be caused by efflux systems but has been linked to class 1 integrons and ISCR elements (1).…”

Infections Caused by Stenotrophomonas maltophilia in Recipients of Hematopoietic Stem Cell Transplantation

“…Only one study showed that TMP-SMZ and fluoroquinolones are equally effective once used as monotherapies in treating S. maltophilia -related infections (53). MDR isolates of S. maltophilia have shown excellent responses to combinations of new fluoroquinolones and tetracycline derivatives (46).…”