RAPD typing of Klebsiella pneumoniae, Klebsiella oxytoca, Serratia marcescens and Pseudomonas aeruginosa isolates using standardized reagents

Objective: To perform quality assessment of standardized random amplified polymorphic DNA (RAPD) analysis for epidemiologic typing of Klebsiella pneumoniae, K. oxytoca, Serratia marcescens and Pseudomonas aeruginosa. Methods: Thirty K. pneumoniae, 15 K. oxytoca, 30 S. marcescens and 33 P. aeruginosa epidemiologically unrelated isolates and four collections of clinically related isolates of each species were included in the study. RAPD analysis was performed using Ready‐To‐Go RAPD Analysis beads with primer ERIC‐1R and Ready‐To‐Go primer 2 for K. pneumoniae and K. oxytoca, primer set ERIC‐2/1026 and Ready‐To‐Go primer 2 for S. marcescens, and primers D‐10514 and D‐14306 for P. aeruginosa. Results: All epidemiologically unrelated K. pneumoniae and K. oxytoca isolates were distinguished. Twenty‐nine types were distinguished among the 30 unrelated S. marcescens isolates and 32 types among the 33 unrelated P. aeruginosa isolates. Indistinguishable banding patterns were obtained in repeated analyses of two isolates and from 11 serial subcultures of three isolates of each species included in the study. The RAPD data from the clinically related isolates correlated with the epidemiologic origin of the isolates. Conclusions: The use of Ready‐To‐Go RAPD Analysis beads resulted in reproducible and stable banding patterns with a high discriminatory capacity, and the RAPD typing results corresponded with the epidemiologic origin of the isolates.