Stenotrophomonas maltophilia infections.

Stenotrophomonas maltophilia is a ubiquitous, gram-negative organism that causes hospital-acquired infections. Persons often come in contact with S. maltophilia through environmental water sources, including hospital tap water or faucets, and it has been associated with nosocomial outbreaks of infection. S. maltophilia often infects debilitated persons and those with underlying medical conditions, including immunosuppression. Manifestations of infection include pneumonia, often in mechanically ventilated patients, bacteremia, skin and soft tissue infection, urinary tract infection, and endocarditis. Treatment of S. maltophilia infection is difficult because the organism is resistant to a number of agents typically used for hospital-acquired infections. In vitro and clinical data indicate that trimethoprim-sulfamethoxazole is the agent of choice. Beta-lactamase inhibitors such as clavulanate are also active, and combination therapy may be indicated for certain serious infections due to S. maltophilia.