COMPARISON OF ARBITRARILY PRIMED POLYMERASE CHAIN-REACTION AND CELL-ENVELOPE PROTEIN ELECTROPHORESIS FOR ANALYSIS OF ACINETOBACTER-BAUMANNII AND A-JUNII OUTBREAKS

Two successive Acinetobacter outbreaks in a neonatal intensive care un it were studied with arbitrarily primed polymerase chain reaction (AP- PCR), cell envelope protein electrophoresis (protein fingerprinting) a nd antibiotic susceptibility testing. AP-PCR fingerprinting and protei n fingerprinting yielded identical clustering of the isolates studied. Susceptibility test results were useful for rapid recognition of the outbreaks, but clustering of several isolates was different from the c lustering obtained with AP-PCR fingerprinting and protein fingerprinti ng. Typing results indicated that the two outbreaks, which occurred at a three-month interval, were each caused by a single strain, and that both strains differed from the strains prevailing in the hospital. Th e strain of one outbreak was identified as A. junii, a species commonl y not involved in outbreaks. A. baumannii isolates collected from diff erent departments of this hospital during a period of four years clust ered into only five different types. Moreover, strains from different departments of a second hospital belonged to the type prevailing in th e first hospital, although there were no apparent connections between the two institutions. This may indicate that only a limited number of strains of the A. calcoaceticus-baumannii complex are involved in noso comial outbreaks.