[New Delhi metallo -beta-lactamase-1 (NDM-1) producing bacteria].

New Delhi metallo-beta-lactamase-1 (NDM-1) producing organisms are now becoming highly prevalent worldwide. We detected first two Japanese cases infected by Escherichia coli in Dokkyo Medical University Hospital and Klebsiella pneumoniae in Saitama Citizen Medical Center. These two NDM-1-producing bacteria are resistant to multiple antibiotic drugs including carbapenems, aminoglycosides, and fluoroquinolones. The genetic analysis showed that these two bacteria possessed different NDM-1 plasmids. Although the patient with E. coli had previously been treated in India, MLST typing showed that these bacteria are distinct from the reported ST clones elsewhere in the world. These results suggest that NDM-1 plasmids are highly variable and transferable to wide-range organisms. We warrant rigorous surveillance and strict infection control.