Epidemiological investigation of Pseudomonas aeruginosa nosocomial bacteraemia isolates by PCR-based DNA fingerprinting analysis

Between July 1994 and March 1995, 64 isolates of Pseudomonas aeruginosa were implicated in bacteraemia in 25 cancer patients in five wards of two hospitals, These, together with 24 environmental isolates and one isolate from a bacteraemia in a noncancer patient were examined random amplified polymorphic consensus (ERIC)-PCR, and 16S-23S spacer region-based RAPD, These methods were reproducible, discriminatory and showed close agreement; all indicated that 47 isolates that had caused bacteraemia in 19 cancer patients were indistinguishable. Seventeen other isolates that had caused bacteraemia in 10 cancer patients were discriminated into eight further groups, and the 24 environmental and non-cancer patient isolates into further distinct groups, No environmental source of the epidemic strain was found, but it was suspected that the outbreak was related to infusion implants.