ABSTRACT
PURPOSE: Two Korean nationwide studies showed that metallo-beta-lactamases (MBLs)-producing-Pseudomonas spp. are not rare. The aim of this study was to assess the trends of MBL-producing isolates among imipenem-resistant isolates of Pseudomonas spp. MATERIALS AND METHODS: Imipenem-resistant clinical isolates were collected from 23 hospitals and one commercial laboratory participating in the KONSAR program in 2005. Polymerase chain reaction (PCR) was used to detect MBL genes. RESULTS: Alleles of MBL genes were detected in 10.8% of 415 Pseudomonas aeruginosa and 66.7% of 12 P. putida isolates from 18 of 24 hospitals/laboratory. Among the 14 IMP-1-like and 39 VIM-2-like MBLs, emergence of IMP-6 was detected for the first time. CONCLUSION: Prevalence of MBL-producing P. aeruginosa has not significantly increased, but IMP-6 emerged in P. aeruginosa.