临床分离34株志贺氏菌菌群分布及耐药性分析

Analysis of serotype distribution and resistance of 34 strains of clinical isolated Shigella

目的了解安徽省近期临床分离志贺氏菌群分布、耐药情况及产生耐药的主要机制,为全省细菌性痢疾的防治工作提供参考资料。方法应用血清凝集法检测志贺氏菌的血清型,K-B法检测志贺氏菌对17种抗生素的敏感性,双纸片扩散法检测超广谱β-内酰胺酶（ESBLs）,PCR法检测ESBL耐药基因型。结果分离的34株菌全部是福氏志贺氏菌,其中2a、1a、4c、4a和X变种分别占47.1%、26.5%、17.6%、2.9%和5.9%;34株菌对氨苄青霉素、四环素、氯霉素和磺胺甲基异恶唑/甲氧氨苄嘧啶的耐药率分别为：100%、97.1%、97.1%和91.2%,对哌拉西林/三唑巴坦和美罗培南的耐药率分别为：29.4%和0.0%;47.1%的志贺氏菌产ESBLs;TEM、SHV、CTX-M-2、CTX-M-14和CTX-M-15检出率分别为：26.5%、0.0%、0.0%、17.6%和26.5%。结论本次分离的志贺氏菌以福氏2a型为主,对常用抗生素耐药情况较严重,其耐药机制主要是产生TEM型和CTX-M-14,15型ESBLs。

Objective To understand serotype distribution, resistance, main resistance mechanism of Shigella strains i- solated from clinical cases, in order to provide reference for the prevention and treatment of bacillary dysentery. Methods Serum agglutination was used to assay Shigella serotypes, K - B method to detect antibiotic susceptibility to 17 kinds of anti- biotics, double disk test to detect extended - spectrum β - lactamase （ ESBLs ） , resistance gene was detected by PCR. Re- suits 34 isolates were all Shigella flexneri, 2a, 1 a, 4c, 4a and X type accounted for 47.1% , 26.5% , 17.6% , 2.9% and 5.9% respectively. The resistance rates of 34 strains to ampicillin, tetracycline, chloramphenicol and Sulphamethox- azole/trimethoprim were 100%, 97.1%, 97.1%, and 91.2% respectively. The resistance to piperacillin/tazobactam and meropenem were 29.4% and 0.0% respectively. 47.1% of Shigella produced ESBLs. Detection rates of TEM, SHV, CTX -M-2, CTX-M-14 and CTX-M-15 were 26.5%, 0, 0, 17.6% and 26.5% respectively. Conclusion Flexneri 2a type was main strains among the 34 strains, resistant to commonly used antibiotics was serious. TEM and CTX - M - 14, 15 extended - spectrum β - lactamase were the principal mechanism of resistance.