title: Clinical implications of stenotrophomonas maltophilia resistant to trimethoprim-sulfamethoxazole: a study of 69 patients at 2 university hospitals.
abstract: We conducted a retrospective case study at 2 tertiary care centers to determine the clinical implications of trimethoprim-sulfamethoxazole resistant Stenotrophomonas maltophilia (TSRSM). Of 69 reviewed cases (mean age, 57 y; male gender, 70%), 40 (58%) were classified as infections associated with TSRSM (respiratory tract, 14; soft tissue, 11; bloodstream, 8; other sites, 7). Severe underlying comorbidities (86%) and previous antibiotic exposure (99%) were common. Cefotetan (susceptibility, 55%), chloramphenicol (49%) and ticarcillin-clavulanate (45%) showed the highest in vitro activity against TSRSM, but were seldom used for therapy (7%). Among the 40 infected cases, 8 developed sepsis disorders and 8 died. Only 1 death could be directly attributed to autopsy-proven TSRSM infection (pneumonia). McCabe score (p = 0.03) and organ dysfunction (p = 0.006) were associated with an increased risk of death in infected patients; exposure to appropriate therapy tended to be protective against death (p = 0.08). 22 infected patients were treated medically; an additional procedure was necessary to clear the infection in 18 cases (surgery, 13; catheter removal, 5). Isolation precautions were rarely exercised, even in the presence of panresistant isolates. In summary, TSRSM-related infections occurred in severely ill patients with extensive exposure to the health-care system, and often required invasive procedures for cure. Infections were directly associated with severe morbidity, and tended to have an indirect rather than a direct impact on mortality.
authors.affiliation: Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
authors.forename: S
authors.initials: S
authors.lastname: Tsiodras
authors.forename: D
authors.initials: D
authors.lastname: Pittet
authors.forename: Y
authors.initials: Y
authors.lastname: Carmeli
authors.forename: G
authors.initials: G
authors.lastname: Eliopoulos
authors.forename: H
authors.initials: H
authors.lastname: Boucher
authors.forename: S
authors.initials: S
authors.lastname: Harbarth
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D024901:Drug Resistance, Multiple, Bacterial; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000188:drug therapy* / Q000382:microbiology / Q000401:mortality; D006761:Hospitals / Q000592:standards; D006801:Humans; D007440:Intubation / Q000009:adverse effects; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009017:Morbidity; D012189:Retrospective Studies; D020615:Stenotrophomonas maltophilia / Q000187:drug effects / Q000472:pathogenicity; D015996:Survival Rate; D014296:Trimethoprim Resistance; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D000900:Anti-Bacterial Agents; D015662:Trimethoprim, Sulfamethoxazole Drug Combination