The Epidemiology Of Pseudomonas Aeruginosa Nosocomial Infection

Objective: To establish RAPD fingerprinting of PA and to type the nosocomial infected PA collected from respiratory ward and ICU, to evaluate the epidemiology of PA nosocomial infection.Methods :Antibiotic susceptibility of 21 nosocomial infected PA strains was analyzed. These strains were typed by RAPD. The consistency of their fingerprintings was observed and compared with their antibiotic susceptibility. The relationship between these 2 things was analyzed.Results : 21 PA strains were divided into 19 multidrug-resistant strains and 2 sensitive strains. In the multidrug-resistant strains, there were 5 strains that had the same antibioticgrams; 2 strains had similar antibioticgrams; the other strains had great difference. The 2 sensitive strains were sensitive to most antibiotics. All the strains produced fingerprintings with RAPD. Typeability was 100%. The 21 PA strains were divided into 15 genotyping. 2 pairs of the 9 strains collected from respiratory ward had the same genotyping. In the 12 PA strains collected from ICU, there were 3 groups (10,11, 15; 13,14; 19,20) that had the same genotyping. The antibiotic susceptibility of the strains was identical or similar when they were the same genotyping. The more similar the number and the positionof the RAPD bands were, the more similar their antibiotic susceptibility was, and vise versa.Conclusion: There were cross-infections of PA in different degree in respiratory ward and ICU. RAPD fingerprint genotyping was suitable for studmg on the epidemiology of microbe infection at molecular level with high typeability, powerful discrimination, rapidness and simplicity. Antibioticgram had certain relation with genotyping, but it could not be regarded as the single foundation of PA typing.