Change in epidemiology of health care-associated infections in a neonatal intensive care unit

Background. Gram-negative rods (GNR) and Candida species are important causes of health care-associated infections in neonatal intensive care units (NICUs). In prior reports, Gram-positive cocci (GPC) have been identified as the most common pathogens causing nosocomial infections in NICUs. Objective. To describe the epidemiology of health care-associated infections in a Level III NICU at a free-standing children's hospital. Methods. All health care-associated infections in neonates from August 1996 to July 2001 were analyzed. Data were collected prospectively by standard surveillance protocols and nosocomial infection site definitions from the National Nosocomial Infection Surveillance system of the Centers for Disease Control and Prevention. Results. During the 5-year study period, 665 pathogens caused 640 infections in the NICU. GNR were the most common pathogens isolated. Of the 665 pathogens 284 (43%) were GNR, followed by 223 (33.5%) GPC, 106 (16%) fungi and 52 (8%) others. Enterobacter spp. were the most common GNR isolated. Ceftazidime resistance was present in 56 of 81 (69%) Enterobacter isolates. Bloodstream and lower respiratory tract infections were the most common sites of infection. More than one-half of the pathogens (388 of 665) were isolated from neonates weighing less than or equal to1000 g. Conclusions. There is a change in the epidemiology of health care-associated infections in our NICU with a predominance of GNR. This change can impact choice of antimicrobials for the empiric treatment of health care-associated infections in high risk neonates.