Integron-associated imipenem resistance in Acinetobacter baumannii isolated from a regional hospital in Taiwan.
We investigated the genetic properties of imipenem-resistant Acinetobacter baumannii collected from a regional hospital in Taiwan. Pulsed-field gel electrophoresis demonstrated that the isolates were genetically diverse. Polymerase chain reaction, DNA sequencing, and DNA-DNA hybridisation showed that the bla(IMP-1) gene resided as a cassette in a plasmid-borne class 1 integron in two isolates. The majority of the resistant isolates were plasmid-less and carried no bla(IMP), bla(VIM) or bla(CFI) genes, indicating that other uncharacterised metallo-beta-lactamases or mechanisms other than enzyme production are involved in carbapenem resistance in this group of A. baumannii. We conclude that multidrug resistance of A. baumannii was a combined effect of lateral gene transfer and clonal spread of multiple resistant clones. Strict measures should be implemented to control the further spread of resistance.
Liu
S Y
SY
Department of Molecular Biotechnology, Da-Yeh University, Changhua, Taiwan.
Lin
J Y
JY
Chu
C
C
Su
L H
LH
Lin
T Y
TY
Chiu
C H
CH
D040981:Acinetobacter baumannii / Q000187:drug effects / Q000235:genetics* / Q000502:physiology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D003428:Cross Infection / Q000382:microbiology; D016521:Electrophoresis, Gel, Pulsed-Field; D023061:Gene Order; D006801:Humans; D015378:Imipenem / Q000494:pharmacology*; D032023:Integrons; D010957:Plasmids / Q000235:genetics; D016133:Polymerase Chain Reaction; D013624:Taiwan; D018440:beta-Lactam Resistance / Q000235:genetics*; D001618:beta-Lactamases / Q000235:genetics
D000900:Anti-Bacterial Agents; D015378:Imipenem; C409201:beta-lactamase IMP-1; C425108:beta-lactamase bla(vim-2); D001618:beta-Lactamases