天津地区30年跨度幼儿感染志贺菌属耐药性与基因型分析

Drug resistance and genotype of Shigella spp. in children over three decades in Tianjin

目的探究天津地区30年间幼儿感染志贺菌属耐药性及流行病学特征。方法对2010年-2011年收集的志贺菌属临床分离株66株与1981年-1983年保存的30株进行药物敏感试验,以基因组重复序列PCR技术(REP-PCR)对两个时间跨度的95株菌进行同源性分析,并对其中的20株菌以多位点序列分型(MLST)分析其生物进化情况。结果 2010年-2011年相比较于1981年-1983年福氏志贺菌对多种抗生素的耐药率均有不同程度增加。2010年-2011年福氏志贺菌对多种抗生素的耐药率均高于宋内志贺菌。REP-PCR技术将59株福氏志贺菌分为51个基因型,36株宋内志贺菌分为18个基因型;20株志贺菌经MLST分析,分为3个ST型和2个序列复合体。结论天津地区抗生素的长期使用导致志贺菌的耐药性明显增加,福氏志贺菌的总体耐药性高于宋内志贺菌。1981年-1983年的志贺菌30年后在天津地区仍有克隆流行。30年来,天津地区志贺菌的生物进化无明显改变。

Objective To understand the antimicrobial resistance and epidemiological characteristics of Shigella spp. in chil- dren over three decades in Tianjin. Methods Sixty - six strains of Shigella spp. isolates （29 Shigellaflexneri, 36 Shigella sonnei and 1 Shigella boydii） from 2010 to 2011 and 30 ShigeUaflexneri isolates from 1981 to 1983 were conducted drug sensitivity test. REP - PCR typing technology was used to study the homology of the 95 Shigella strains （ excluding 1 Shigella boydii）, and 20 strains of which were conducted biological evolution analysis by multilocus sequence typing（MIST）. Results Compared to Shigella flexneri isolates during 1981 - 1983, those during 2010 -2011 showed increasing resistance rates to the third and fourth generation cephalosporins, amikacin and ampicillin, and the drug resistance rates of Shigella flexneri to most antibiotics were higer than those of Shigella sonnei. By REP- PCR, 59 strains of Shigellaflexneri belonged to 51 genotypes, 36 strains of Shi- gella sonnei belonged to 18 genotypes. In addition, 20 Shigellaflexneri strains were divided to 3 sequence types （ST） and two sequence type complexes by MLST. Conclusion Long - term antibiotics use has lead to the significant increase of drug resist- ance of Shigella. Shigella flexneri showed higher drug resistance rates to most antibiotics than ShigeUa sonnei. The Shigella iso- lates in 1981 - 1983 were still prevalent in Tianjin after three decades. There was no change in the biological evolution of Shi- gella spp. during the three decades.