Water supply as a source of Pseudomonas aeruginosa in a hospital for hematological malignancies.

This report details of an investigation on a significant increase in nosocomial bacteremias due to multiply-resistant Pseudomonas aeruginosa strains which occurred in a hematological ward. Serotyping according to Habs method showed a high frequence of the serotype 12. Control cultures identified in the hospital building water reservoirs the presence of the organism. After disinfection of these water reservoirs, the frequence of nosocomial septicemias caused by serotype 12 Pseudomonas aeruginosa strains on the overall bacteremic episodes declined immediately and showed a declining trend in the following 13 months period. To conclude serotyping of Pseudomonas aeruginosa is a useful epidemiological marker and allows to discover from where the diffusion of the organism responsible of outbreaks starts.