作者: Lingyi Zeng , Jisheng Zhang , Chunjiang Li , Yanjun Fu , Yongxin Zhao
DOI: 10.1016/J.MEEGID.2020.104319
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摘要: Abstract Background There is increasing resistance to carbapenems among Klebsiella pneumoniae,and fluoroquinolones (FQ) are increasingly used treat infections from extended-spectrum β- lactamase(ESBLs) and carbapenemase-producing pneumoniae. However, the acquisition of plasmid-mediated quinolone (PMQR) or spontaneous mutation resistance-determining regions (QRDR) gyrA parC genes can severely affect therapeutic effect quinolones. The goal this study was investigate molecular determinants FQ resistance(FQ-R) in carbapenem-resistant pneumoniae (CRKP) isolates Heilongjiang Province,China. Materials methods We isolated 40 strains CRKP a treatment center eastern part Province January 2016 December 2018. VITEK2 Compact analyzer identify detect drug sensitivity. Different types were detected by polymerase chain reaction (PCR). PCR DNA sequencing assess presence qnrA, qnrB, qnrS,qepA acc(6′) Ib-cr genes,which plasmid-encode that contribute resistance. sequences sequenced compared with standard determine if mutations present.Multi-site sequence typing (MLST) pulsed-field gel electrophoresis (PFGE) performed on homology. Results showed rates 22.5% 42.5%. rate ciprofloxacin significantly higher than levofloxacin.Nine (22.5%) co-resistance levofloxacin.The resistant screened for plasmid-encoded (PMQR genes).Among 17 strains,one strain contained no PMQR genes,twelve two genes,and four genes.Acc (6′) most frequently gene, 95% tested (38 40) 94.1% quinolone-resistant (16 17). qepA gene encoding an efflux pump not any strains.No isolate carried five different PMQRs simultaneously.Changes S83I D87G changes gyrA, S80I change parC,which mediated QRDR,were identified isolates,which both levofloxacin.Most FQ-R strains(58.8%,10/17) belong ST(sequence type) 76, which dominant local area, while all mutant (100%,2/2),that differ at least one site bacteria, ST11 group. hospital where there had been recent outbreak ST76 type neurosurgery ward intensive care unit. Conclusion insensitive even quinolones,and common China;fluoroquinolone-resistance these clinical complex interplay between parC.The level caused QRDR PMQR, however, high frequency suggests potential impact genes.PMQR often found ESBLs-producing some genes,such as:SHV,TEM, CTX-M-15,and OXA-1 closely associated FQ-R. Finally, geographical factors emergence spread QRDR.Some genetic lineages have risks, continuous close monitoring required.