Genetic diversity of Pseudomonas aeruginosa strains isolated from ventilated patients with nosocomial pneumonia, cancer patients with bacteremia, andenvironmental water

Random amplified polymorphic DNA typing was used to study the genetic diver sity of Pseadomonas aeruginosa strains from (i) ventilated patients with no socomial pneumonia who were hospitalized in intensive care units, (ii) case s of bacteremia in cancer patients with severe neutropenia, and (iii) river s and swimming pools. Genetic diversity was determined by three phylogeneti c methods and by statistical analysis of population genetics. The populatio n studied undergoes epidemic clonality with a high rate of genetic recombin ation. P. aeruginosa bacteremia and pneumonia are not caused by specific cl ones within this species.