Survey of Acinetobacter baumannii Isolates in a NICU at a General Hospital

Ventilator-associated pneumonia caused by multidrug-resistant Acinetobacter baumannii in intensive care units has become a problem worldwide. In Japan, few reports of antimicrobial susceptibility or nosocomial infection have involved A. baumannii. We confirmed A. baumannii nosocomial infection in a neonatal intensive care unit (NICU) of general hospital A in the Tohoku region from May 2008 to February 2009, so spreading of infection and environmental contamination were examined. Antimicrobial susceptibilities of 51 clinical isolates in NICU and 2 environmental isolates, thermometer and knob, in March 2009 were determined by the micro-dilution method. Furthermore, the genotype of these strains was determined using the AP-PCR and ERIC-PCR methods. During this period, three nosocomial infections (June, September, February) caused by A. baumannii were confirmed. In this study, there was no isolation of multidrug-resistant strains. The genotype of each A. baumannii strain in these nosocomial infections was different. The genotype of the A. baumannii strain isolated from the thermometer which only patient A had used was identified with that of the nosocomial infection in February. These results showed the possibility that several A. baumannii strains were transmitted through staff of the NICU. A. baumannii surveillance may be important to prevent nosocomial infection in the NICU.