产ESBLs肺炎克雷伯菌耐药性及基因分型

Antimicrobial resistance and gene typing of extended-spectrum β-lactamases-producing Klebsiella pneumoniae

目的了解某院临床分离的产超广谱β-内酰胺酶(ESBLs)肺炎克雷伯菌的耐药性及基因型。方法收集临床分离的肺炎克雷伯菌,采用美国临床实验室标准化委员会2005年推荐的方法进行ESBLs初筛及表型确证试验;K-B纸片扩散法进行抗菌药物敏感性试验;聚合酶链反应(PCR)法分析产ESBLs菌株的基因类型。结果产ESBLs肺炎克雷伯菌的检出率为62.22%(56/90)。产ESBLs菌仅对第三代头孢菌素与β-内酰胺酶抑制剂合剂、碳青霉烯类抗生素较敏感。基因型分析结果显示,产ESBLs肺炎克雷伯菌中SHV型、CTX-M 1型、TEM型、CTX-M-9型的检出率分别为69.64%、51.79%、37.50%、0.00%,同时携带2种、3种耐药基因的菌株分别占35.71%和14.28%。结论产ESBLs肺炎克雷伯菌耐药严重,基因型以SHV、CTX-M-1为主。

Objective To investigate antimicrobial resistance and genotypes of extended-spectrum β-lactamases （ESBLs）-producing Klebsiella pneumoniae（K, pneumoniae） isolated from clinic in a hospital. Methods K. pneumoniae were collected, ESBLs preliminary screen and phenotype confirmatory tests were carried out according to the NCCLS guidelines; antimicrobial susceptibility tests were determined by Kirby-Bauer test; gene types of β-lactamases were performed with PCR . Results The detection rate of ESBLs-producing K. pneumoniae was 62. 22% （56/ 90）. ESBLs-producing strains were only sensitive to the combination of the third generation cephalosporins with β- lactamases inhibitor and carbapenems. The detection rate of genes of SHV, CTX-M-1, TEM and CTX-M-9 was 69. 64%, 51.79%, 37. 50% and 0. 00% respectively. 35. 71% and 14. 28% of ESBL-producing K. pneumoniae carried two or three genes respectively. Conclusion Antimicrobial resistance of K. pneurnoniae is serious, the main gene types are SHV and CTX-M-1 .