Detection and characterization of class 1 integrons among carbapenem-resistant isolates of Acinetobacter spp. in Malaysia.
OBJECTIVE
To detect and characterize class 1 integrons among carbapenem-resistant strains of Acinetobacter spp. at University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia.


METHODS
Thirty nine carbapenem-resistant Acinetobacter strains were obtained from UMMC from August 2003 to March 2004 and analyzed for the presence of bla(IMP) genes and class 1 integrons.


RESULTS
Class 1 integrons were detected in 31 of 39 strains. Two Acinetobacter calcoaceticus strains harbored an integron-borne bla(IMP-4) metallo-beta-lactamase, 1 of which was located on a 36-kb plasmid. Two different amplified products were found in the 31 isolates with 3 restriction pattern profiles 1, 2, and 3. Correlation was observed between carriage of class 1 integrons and genomic relatedness among these isolates, indicating that particular mechanisms of carbapenem resistance could have been acquired by genotypically distinct clinical isolates of Acinetobacter spp.


CONCLUSIONS
Although class 1 integrons are widely disseminated among clinical isolates of Acinetobacter spp. they do not play a major role in the spread of carbapenem resistance.
Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
Wong Eng
WE
Hwa
Geetha
G
Subramaniam
Parasakthi
P
Navaratnam
Shamala Devi
SD
Sekaran
D000150:Acinetobacter / Q000187:drug effects / Q000235:genetics*; D015780:Carbapenems / Q000378:metabolism / Q000494:pharmacology; D016521:Electrophoresis, Gel, Pulsed-Field; D032023:Integrons / Q000235:genetics*; D008296:Malaysia; D008826:Microbial Sensitivity Tests; D016133:Polymerase Chain Reaction; D018440:beta-Lactam Resistance / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
D015780:Carbapenems; C425142:beta-lactamase IMP-4; D001618:beta-Lactamases