MOLECULAR EPIDEMIOLOGIC-STUDY OF PSEUDOMONAS-AERUGINOSA ISOLATES FROM PATIENTS WITH ACUTE-LEUKEMIA

In an attempt to determine the genetic relationship between strains of Pseudomonas aeruginosa isolated from patients with acute leukemia, a recently described restriction fragment from the region upstream of the exotoxin A structural gene was used as a probe in Southern hybridization. The overall rate of cultures positive for Pseudomonas aeruginosa during 169 admissions (119 patients) was 17 %. Twelve genotypically distinct strains were found among 18 colonized and/or infected individuals. Three of these strains were recovered from more than one patient, suggesting a certain risk of nosocomial transmission of Pseudomonas aeruginosa and cross-infection. Genotypic comparison showed identical restriction patterns in multiple isolates from single patients, and also in colonizing and subsequently infecting strains. Genotyping distinguished isolates with similar O serotypes and established the identity between isolates with differing susceptibility to agents used for antibacterial prophylaxis. © 1990 Friedr. Vieweg & Sohn Verlagsgesellschaft mbH.