COMPARISON OF POLYMERASE CHAIN-REACTION AND PULSED-FIELD GEL-ELECTROPHORESIS FOR THE EPIDEMIOLOGIC TYPING OF ALCALIGENES XYLOSOXIDANS SUBSPXYLOSOXIDANS IN A BURN UNIT

Eighteen isolates of Alcaligenes xylosoxidans subsp. xylosoxidans were collected from clinical specimens of 15 patients in a burn unit and a plastic surgery ward over a 16-month period. Pulsed-field gel electro phoresis and polymerase chain reaction (PCR) were compared for the epi demiologic typing of these 18 isolates and fifteen epidemiologically u nrelated strains. These 18 isolates demonstrated an identical fingerpr int pattern and were easily distinguished from the 15 epidemiologicall y unrelated strains by pulsed-field gel electrophoresis typing and bot h enterobacterial repetitive intergenic concensus and repetitive extra genic palindrome-primed PCR fingerprinting. We conclude that pulsed-fi eld gel electrophoresis analysis of XbaI-digested genomic DNA is a hig hly discriminatory and reproducible method for epidemiological typing of A. xylosoxidans subsp. xylosoxidans isolates. However, poor resolut ion due to frequent cutting in the smaller fragments (<145.5 Kb) may l end to difficulty in interpretation. PCR is a vapid and highly discrim inatory, but less reproducible, technique with occasional loss of majo r bands. The fingerprints produced by repetitive extragenic palindrome primed PCR had more intense bands and were easier to read than those produced by enterobacterial repetitive intergenic concensus-primed PCR in this study. (C) 1997 Elsevier Science Inc.