CLONAL IDENTIFICATION OF AEROMONAS-HYDROPHILA STRAINS USING RANDOMLY AMPLIFIED POLYMORPHIC DNA ANALYSIS

The suitability of arbitrary primer polymerase chain reaction (RAPD) a s a typing technique was evaluated by comparing it with pulsed-field g el electrophoresis (PFGE) to characterize Aeromonas hydrophila strains isolated from a cluster of hospital-acquired infections. Five isolate s from patients and 10 isolates from the water supply were compared to 10 epidemiologically unrelated strains isolated from patients and riv ers. Two methods were used to prepare DNA and two primers (AP3 and AP5 ) were selected. The discriminatory power was better with the extracti ve DNA preparation than the boiling method. The discrimination of clos ely related from less related strains by PCR using AP3 was consistent with that by PFGE: water supply of Cholet hospital contaminated with A eromonas species was not the source of the cluster sf hospital infecti ons and only two patients were infected with clonally-related strains. RAPD using primer AP3 was simpler, cheaper, and quicker to perform th an pulsed-field gel electrophoresis and is well suited for the epidemi ological study of A. hydrophila isolates.