Abstract
Carbapenem non-susceptible Pseudomonas aeruginosa and Acinetobacter baumannii strains were tested for the presence of metallo-beta-lactamases (MBLs) by EDTA-synergy screening. Imipenem hydrolysis was investigated by a bioassay and IMP-/VIM-encoding genes by PCR. No bla(IMP/VIM) related genes or imipenemase activity were detected although E-test found all strains as MBL-positive. Disk synergy tests with 0.5 M EDTA determined 63.6-100%, while those with 0.1 M EDTA detected 0-7.7% of isolates as MBL producers. Most strains were susceptible to EDTA. In conclusion, for MBL-screening purposes, EDTA-synergy results change with molarity of EDTA, but even if some false positives are encountered, 0.1 M EDTA seems to be acceptable.
Publication types
-
Evaluation Study
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Acinetobacter Infections / epidemiology
-
Acinetobacter Infections / microbiology
-
Acinetobacter baumannii / drug effects*
-
Acinetobacter baumannii / enzymology
-
Acinetobacter baumannii / genetics
-
Adult
-
Anti-Bacterial Agents / pharmacology*
-
Child
-
Disk Diffusion Antimicrobial Tests
-
Drug Resistance, Bacterial
-
Edetic Acid / pharmacology
-
Genotype
-
Humans
-
Imipenem / pharmacology
-
Microbial Sensitivity Tests / methods*
-
Phenotype
-
Polymerase Chain Reaction / methods*
-
Pseudomonas Infections / epidemiology
-
Pseudomonas Infections / microbiology
-
Pseudomonas aeruginosa / drug effects*
-
Pseudomonas aeruginosa / enzymology
-
Pseudomonas aeruginosa / genetics
-
Turkey / epidemiology
-
beta-Lactamases / biosynthesis*
-
beta-Lactamases / genetics
Substances
-
Anti-Bacterial Agents
-
Imipenem
-
Edetic Acid
-
beta-Lactamases