Nosocomial stenotrophomonas maltophilia infections in children: Results of a 5-year study

Abstract

Aim: The aim of this study was to determine the incidence of nosocomial infections, to analyze the risk factors associated with mortality of the patients with Stenotrophomonas maltophilia infections and to evaluate the episodes of S. maltophilia nosocomial infections in pediatric patients.Material and Method: The data of children with positive cultures, who were diagnosed to have nosocomial infection using the Centers for Disease Control and Prevention criteria, were reviewed and only the patients with nosocomial S. maltophilia infection were included in the study.Results: Between January 1, 2003 and December 31, 2007, a total of 1,439 episodes of nosocomial bacterial infections were observed. Culture proven nosocomial infection rate was 14%. During the study period, a total of 28 nosocomial S. maltophilia infection episodes were identified in 28 patients. The mean age of the patients was 25.8+37.1 months (12 days-15 years) and 54% were male. The most frequently seen nosocomial S. maltophilia infections were ventilator-associated pneumonia (VAP) (78.5%), bacteremia (14.3%), bacteremia plus soft tissue infection (3.6%) and meningitis ( 3.6%). Twenty percent of the patients with S. maltophilia bacteremia had soft tissue involvement. Most of the patients (60.7%) were neonates, followed by the pediatric intensive care unit patients (28.6%). Prematurity (53.6%) was the most common underlying condition. Malignancy (40%) was the major underlying disease in the patients with S. maltophilia bacteremia. In this study, risk factors for nosocomial S. maltophilia infections included the underlying disease, prolonged hospitalization, previous therapy with broad-spectrum antibiotics, presence of a central venous catheter, mechanical ventilation and a stay in the intensive care unit. Predisposing factors associated with mortality of the patients with nosocomial S. mal-tophiliainfections were prolonged antibiotic therapy and the presence of urinary catheter (p<0.05). All the S. maltophilia isolates were susceptible to trimetoprim-sulfamethoxazole. In this study, the mortality rate of all children with nosocomial S. maltophilia infections was found to be 28.6%Conclusion: In our patients, VAP was the most common nosocomial S. maltophilia infection and malignancy was the most frequent underlying disease in the patients with nosocomial S. maltophilia bacteremia. Predisposing factors associated with the mortality of patients with nosocomial S. maltophilia infections were prolonged antibiotic therapy and the presence of urinary catheter.