Drug resistance and genotype of -lactamases-producing Klebsiella pneumoniae in ICU patients with nosocomial infection

Objective To explore the genotype and the drug resistance characteristics of ESBLs and AmpC-lactamase producing Klebsiella pneumoniae in ICU patients with nosocomial infection and provide evidence for the clinical medication. Methods The isolates were identified with VITEK 60 System; the ESBLs detection and drug sensitivity test (Kirby-Bauer method) were conducted according to the standards recommend by CLSI; the suspected AmpC-lactamase producing strains were screened with cefoxitin disk diffusion test. the genotypes were analyzed with cefoxitin three-dimensional test and PCR sequencing. Results Of the 97 isolates, 31.96% were ESBLs positive, 13.40% were AmpC-lactamase positive. Among them, only AmpC-lactamase producing isolates accounted for 7.22%; both AmpC-lactamase and ESBLs producing isolated accounted for 6.19%; only ESBLs producing isolates accounted for 25.77%. The drug resistant genes of all 13 AmpC-lactamase positive strains belonged to genotype DHA-1. ESBLs producing strains were resistant to more drugs than the non ESBLs producing strains. Both AmpC-lactamase and ESBLs producing isolates had more serious drug resistance. Conclusion The detection rates of AmpC-lactamase and ESBLs producing Klebsiella pneumoniae were high in ICU patients. All the AmpC-lactamase belonged to genotype DHA-1 and both AmpC-lactamase and ESBLs producing Klebsiella pneumoniae strains were multi-drug resistant.