Detection of metallo-β-lactamase producing clinical gram-negative non-fermenting isolates

There is a remarkable increase in antibiotic resistance due to metallo-β-lactamase-production among gram-negative non-fermenting organisms. Early detection of metallo-β-lactamase (MBL) producing isolates is necessary to prevent their dissemination. Imipenem-EDTA disk method was used for the detection of MBL producing strains among multidrug resistant (MDR) Acinetobacter species and Pseudomonas aeruginosa. One hundred MDR Acinetobacter spp. and forty-two Pseudomonas aeruginosa were screened for MBL production, from January to June 2001. MBL was produced by 96.6 % of imipenem-resistant Acinetobacter isolates, whereas 100% imipenem-resistant Pseudomonas aeroginosa isolates were MBL producers. MBLs are responsible for carbapenem resistance in these MDR Acinetobacter spp. and Pseudomonas aeruginosa There is an urgent need to have a simple screening test to take infection control measures on time.