Genetic elements of drug-resistance in a strain of multidrug-resistant Klebsiella pneumoniae isolated from bronchoalveolar lavage fluid / 中华临床感染病杂志

ABSTRACT

Objective To analyze the resistance genes in a muhidrug resistant Klebsiella pneumoniae (MDRKP) strain.Methods A MDRKP strain was isolated from bronchoalveolar lavage fluid in Pediatric Intensive Care Unit of Children's Hospital Affiliated to Soochow University in February 2012.Acquired resistance genes to beta-lactams,aminoglycosides,quinolones,ompK35 and ompK36 gene for outer membrane porin protein,and carbapenems targeting PBP2 gene were analyzed by PCR and verified by DNA sequencing.Results Acquired resistance genes TEM-1,SHV-1 to beta-lactam antimicrobial agents and aac(6′)-I b to aminoglycoside antimicrobial agents were positive in the strain of MDRKP.While 16S rRNA methylase,ompK35 and ompK36 genes for outer membrane porin protein were negative.Compared with susceptible strains,there were 9 synonymous mutations in PBP2 gene sequence of this MDRKP strain,but the amino acid sequences were the same.No mutation in quinolone resistance determining region (QRDR) was observed.Conclusion The multidrug resistance of the isolated Klebsiella pneumoniae strain may be related to 2 kinds of beta-lactam acquired resistance genes,1 kind of aminoglycoside acquired resistance gene,ompK35 and ompK36 genes defects and synonymous mutation in PBP2 gene.