Imipenem-EDTA Disk Method for Differentiation of Metallo-β-Lactamase-Producing Clinical Isolates of <i>Pseudomonas</i> spp. and <i>Acinetobacter</i> spp

Abstract

Rapid detection of metallo-beta-lactamase (MBL)-producing gram-negative bacilli is necessary to prevent their dissemination. The method using a disk with imipenem plus 750 micro g of EDTA differentiated all MBL-producing pseudomonads, and the sensitivity and specificity for acinetobacters were 95.7 and 91.0%, respectively. The imipenem-EDTA disks were stable for 12 and 16 weeks at 4 and -20 degrees C, respectively.