Detection of a highly prevalent and potentially virulent strain of Pseudomonas aeruginosafrom nosocomial infections by RAPD analysis

Background: We correlated genotypes, virulence factors and antimicrobial susceptibility patterns of nosocomially identified Pseudomonas aeruginosa isolates from clinical specimens to those of environmental isolates encountered in the same units of a medical center. Antibiotic susceptibility testing, RAPD analysis and detection of enzymatic activities of extracellular virulence factors, were done on these isolates. Results: Data showed that most of the clinical and environmental isolates were susceptible to tested antimicrobial agents. RAPD analysis determined the presence of 31 genotypes, with genotype 1 detected in 42% of the clinical isolates and 43% of the environmental isolates. Enzymatic activity testing showed that genotype 1 produced all virulence factors tested for. Conclusions: In conclusion, our data demonstrated the predominant prevalence of a potentially virulent P. aeruginosa genotype, circulating in the most majority of the medical center units and emphasize the need to reinforce infection control measures.