Detection of metallo-β-lactamase–producing Pseudomonas aeruginosa strains isolated from burn patients in Ahwaz, Iran

The antimicrobial activities of 6 common antimicrobial agents including carbapenems were tested against 100 clinical Pseudomonas aeruginosa isolates using a disk diffusion method. All imipenem (IPM)-resistant isolates were screened for metallo-β-lactamase (MBL) production by Etest assay and were subsequently subjected to polymerase chain reaction (PCR) analysis with the blaIMP and blaVIM genes. Of 41 IPM-nonsusceptible isolates detected, 8 (19.51%) appeared to produce MBL, as determined by Etest. Using PCR assay, these isolates were positive for blaVIM genes, whereas none were positive for blaIMP genes.