Clonal Diversity of Metallo- -Lactamase-Possessing Pseudomonas aeruginosa in Geographically Diverse Regions of Japan

The aim of this study was to determine the distribution of metallo-p-lactamase-producing Pseudomonas aeruginosa in Japan and to investigate the molecular characteristics of resistance gene cassettes including the gene encoding this enzyme. A total of 594 nonduplicate strains of P. aeruginosa isolated from 60 hospitals throughout Japan in 2002 were evaluated. This study indicated that although the prevalence of imipenem-resistant P. aeruginosa has not increased compared to that found in previous studies, clonal distribution of the same strain across Japan is evident.