The changing pathogens of complicated parapneumonic effusions or empyemas in a medical intensive care unit

To assess the incidence, pathogens, and outcome of complicated parapneumonic effusions or empyemas in a medical intensive care unit (MICU) patients with pleural effusions. Prospective study of febrile MICU patients with pleural effusion carried out in a tertiary care hospital between April 2001 and September 2003. The study included 175 patients with a temperature above 38 degrees for more than 8 h with evidence of pleural effusion confirmed by chest radiography and ultrasound. Routine thoracentesis and effusion cultures. The prevalence of complicated parapneumonic effusions or thoracic empyemas in febrile MICU patients with pleural effusions was 45% (78/175). A total of 78 micro-organisms were isolated from the pleural fluid of 58 patients (positive microbiological culture 74%) including aerobic Gram-negative (n=45), aerobic Gram-positive (n=23), anaerobic (n=5), Myobacterium tuberculosis (n=3), and Candida (n=2). The infection-related mortality rate of complicated parapneumonic effusions or empyemic patients in the MICU was 41% (32/78). The development of complicated parapneumonic effusions or thoracic empyemas in MICU patients is a high-mortality disease. The increasing incidence of aerobic Gram-negative pathogens in empyema has become a more urgent problem.