乌鲁木齐地区135株志贺氏菌耐药性调查

目的了解乌鲁木齐地区临床分离肠道致病菌中志贺氏茵的流行趋势及耐药情况，分析产生超广谱β-内酰胺酶（ESBLs）菌株的流行特征及耐药表型和基因型别，为临床合理使用抗生素提供依据。方法志贺氏菌选择培养基采用四区划线法分离培养出135株志贺氏茵，参照Kirby—Bauer纸片扩散法检测其对23种抗生素的耐药性：采用纸片确认试验对多重耐药菌株进行ESBLs表型确证检测；采用聚合酶链式反应（PCR）检测CTX—M、SHV、TEM等耐药基因，对PCR产物测序，通过与美国GenBank核酸库已登录的序列作比对确定基因亚型。结果135株志贺氏菌感染患者中，男性占53．3％（72／135），女性占46．7％（63／135）；高发季节为6—8月；25岁以下发病人数占总发病人数的71．9％（97／135）；对氨苄西林、氯霉素和复方磺胺甲噫唑的耐药率较高，分别达91．1％、68．1％、70．4％。有43株（31．9％）ESBLs表型检测阳性。PCR扩增结果表明，共有19株携带CTX．M基因，其中CTX．M．1群6株，CTX．M-9群13株；4株携带SHV基因；6株携带TEM基因。基因测序确定各基因型存在多种亚型。结论福氏志贺氏茵为本地区优势志贺氏茵。对某些抗生素存在高度耐药性。应引起临床重视。ESBLs耐药菌株以CTX．M型为主，流行亚型为CTX．M．14、CTX—M．15和TEM-1。产CTX．M-24志贺茵在乌鲁木齐属首次报告检出。

SURVEY OF DRUG RESISTANCE IN 135 STRAINS OF SHIGELLA IN URUMQI

Objective To study the drug resistance and epidemic trend of Shigella from clinical isolated intestinal pathogenic bacteria in Xinjiang Urumqi area, and analyse the epidemiological characteristics of resistant phenotype and genotype of bacterial strain producing extended-spectrum β-1actamases （ESBLs）, so as to provide the basis for clinical rational use of antibiotics. Methods One hundred and thirty-five Shigella strains were isolated and cultured by four divisions line method. The drug resistance of 23 kinds of antibiotics were tested using the Kir- by-Bauer agar diffusion method;ESBLs phenotypic multiple drug resistant strains were tested by Kirby-Bauer agar confirmatory test ; and the resistant genes CTX-M, SHV, TEM, etc were amplified by PCR;the sequence of PCR product, and gene subtypes were determined by comparing with those in GenBank. Results In 135 Shigella infection patients, male accounted for 53.3% （72/135） , female 46.7% （63/135） ;high incidence occurred in July to Au- gust;those under the age of 25 accounted for 71.85% （97/135） . The drug resistance rate to ampicillin,chloram- phenicol, and compound sulfamethoxazole was 91.1% ,68.1%, and 70.4% respectively ;43 strains （31.9% ） were ESBLs phenotype positive. PCR amplification showed that a total of 19 strains carried CTX-M gene （6 strains of CTX-M-1,13 strains of CTX-M-9 ） ,4 strains carried SHV gene, and 6 strains carried TEM gene. Also many subtypes were determined by sequencing. Conclusion ShigeUa flexneri which are the predominant bacteria in Urumqi, are highly resistant to some antibiotics, so proper selection of antibiotic for clinical therapy is necessary. CTX-M was the predominant resistant gene of ESBLs strain;and CTX-M-14, CTX-M-15 ,and TEM-1 were the epidemic subtype. The Shigella sonnei carrying CTX-M-24 were detected and reported for the first time in Xinjiang.