Objectives: Stenotrophomonas maltophilia infection is gaining importance as an important cause of nosocomial pneumonia due to its characteristic inherent resistance to many broad- spectrum antibiotics.
Methods: A retrospective 10 years study was carried out to determine the clinical characteristics of all patients with Stenotrophomonas pneumonia, antibiotic resistance pattern, and risk factors associated with hospital mortality. All patients with Stenotrophomonas culture positivity were identified and their medical records were reviewed. Risk factor associated with hospital mortality was analyzed.
Results: 72 patients (median age: 67.3 years; 65.2% males) with S. maltophilia pneumonia, not related to cystic fibrosis, were included. total of 76 samples obtained from 72 patients were culture positive. The 72 patients were hospitalized in medical (61.1%), surgical (5.5%), hematology/oncology departments (8.3%), or the intensive care units (ICU; 25.1%). All patients had comorbidity. Mostly seen comorbidities were COPD, DM, chronic renal failure, malignancy, and cardiac diseases. Percentage resistance to trimethoprim-sulfamethoxazole; 4 (5.5%) was lower than that for fluoroquinolones; 9 (12.5%). 17 patients (23.6%) died during hospital stay. By using multivariate analysis, respiratory insufficiency needed mechanical ventilation, low hemoglobin level, age>65 years, previous antibiotic usage, and hypotension were the independent prognostic factors for mortality.
Conclusion: Stenotrophomonas maltophilia is emerging as an important pathogen with increased risk of mortality in patients with respiratory insufficiency needed mechanical ventilation, low hemoglobin level, age>65 years, previous antibiotic usage, and hypotension. Empiric therapy should include agents active against S.maltophilia such as newer flouroquinolones and trimethoprim-sulfamethoxazole.