Detection of Resistance Genes and Homology Analysis on Carbapenem-resistant Klebsiella Pneumonia

OBJECTIVE To analyze the distribution of resistance gene and homology of carbapenem-resistant Klebsiella pneumoniae(CRKP) isolated from Taizhou Hospital of Zhejiang province. METHODS A total of 41 non-repetitive CRKP isolated were collected from Taizhou Hospital of Zhejiang province from January 2017 to November 2017. VITEK-compact 2 automatic microbial system was used for species identification and antimicrobial susceptibility test(AST), and the further confirm were performed by mass spectrometer VITEK MS and disc diffusion method(K-B method). The screening of A-and B-class carbapenemase phenotypes were tested by phenotypic screening test. The drug-resistant genotypes were detected by PCR and the genotypes were identified by gene sequencing and BLAST comparison. The homology of all 41 strains were analyzed using pulsed field gel electrophoresis(PFGE). RESULTS Phenotypic screening tests showed that all 41 strains of CRKP produced carbapenemase. The rates of bla_KPC, bla_IMP and bla_NDM genes were 95.12%(39/41), 4.88%(2/41) and 2.44%(1/41), respectively. Genes of bla_SIM, bla_SPM, bla_VIM and bla_GIM were not detected in all strains. Sequencing results indicated that bla_KPC-2, bla_NDM-1 and bla_IMP-4were the most popular sub-types in bla_KPC, bla_NDM and bla_IMP. Strains could be divided into A-N subcluster by PFGE. Type A(17/41, 41.46%), type B(9/41, 21.95%) and type C(4/41, 9.76%) were the main spectrum types. Type A was mainly distributed in Neurosurgery Department, type B and C were mainly in Department of Critical Care Medicine. CONCLUSION bla_KPC-2 is the main carbapenem-resistant gene of CRKP in Taizhou hospital of Zhejiang province, and exist clonal spread. Hospital infection control departments and clinical departments shall pay attention and take effective measures to control the spread of drug-resistant strains.