宁夏志贺菌病原学特征分析

Pathogenic characterization of Shigella isolated from Ningxia

目的探讨宁夏地区志贺菌菌群分布、药物敏感性情况,并通过同源性分析研究其分子流行病学特征,为菌痢防控提供依据。方法通过系统生化条(API20E)鉴别菌株,用血清玻片凝集鉴定菌型,采用K-B法检测分离菌株对10种常用抗生素的敏感性,并应用脉冲场凝胶电泳技术(PFGE)进行分子分型,所得结果用BioNumericsV4.0软件UPGMA方法进行聚类分析。结果 176株志贺菌中,福氏志贺菌112株,占63.64%,其中福氏2b型52株,占29.55%;宋内志贺氏菌64株,占36.36%。药敏试验显示耐药率最高的药物为氨苄西林、萘啶酸、四环素、利福平;其次为阿莫西林、复方新诺明;而敏感性最高药物依次为环丙沙星(CIP)、头孢噻肟和头孢噻吩,其中福氏志贺菌和宋内志贺菌对10种抗生素的耐药谱略显不同;112株福氏志贺菌共分为36个带型,其中,JZXN11.NX06、JZXN11.NX07、JZXN11.NX021、JZXN11.NX0025占所有分型菌株的57.14%,为我省主要的暴发型。64株宋内志贺菌分为21个带型,J16X01.NX0011和J16X01.NX0012为两个主要流行带型,分别占分型菌株的31.25%和15.63%。结论本省志贺菌流行以福氏为主,其中F2b为优势菌型,F4c和宋内氏菌检出率显著增高;志贺菌对氨苄西林(AMP)、四环素(Te)、阿莫西林(AML)和萘啶酸耐药率最高,多重耐药现象严重;PFGE型别呈现多元化流行特点,流行的优势带型减弱、多种型别并存的复杂形态。

The objective of the present study was to investigate the distribution and drug susceptibility of Shigella bacteria in Ningxia,and provide the basis for prevention and control of bacillary dysentery through homology analysis of molecular epidemiology.Biochemistry of API20E system was used to identify strains,and the bacteria categories were tested by slide agglutination with a serum.The sensitivity of strain to 10 commonly used antibiotics was detected with Kirby-Bauer assay,and pulsed-field gel electrophoresis（PFGE） was used for molecular typing.The results were analysed by BioNumerics V4.0 and UPGMA method.Among the 176 Shigella,there were 64 Shigella sonnet（36.36%） and 112 Shigella flexneri（63.64%） which containing 52 Shigella flexneri 2b（29.55%）.Results showed that drugs with higher resistance rate were ampicillin,nalidixic acid,tetracycline and rifampin,following by amoxicillin and cotrimoxazole.The most sensitive drugs were ciprofloxacin（CIP）,cefotaxime and cephalothin;the test also showed that Shigella flexneri and Shigella sonnet had slight difference in resistance spectrum to 10 antibiotics.The 112 Shigella flexneri were divided into 36 banding patterns,in which JZXN11.NX06,JZXN11.NX07,JZXN11.NX021,JZXN11 and NX0025,accounting for 57.14%,were the main outbreak types in Ningxia.The 64 Shigella sonnet were divided into 21 banding patterns,in which J16X01.NX0011 and J16X01.NX0012 were the 2 epidemic banding patterns,accounting for 31.25% and 15.63% respectively.It indicates that in Ningxia,the most popular Shigella bacteria is Shigella flexneri,and F2b is the dominant serotype.The detection rate of F4c and Shigella sonnet have decreased significantly.The drug resistance rate of Shigella to ampicillin（AMP）,tetracycline（Te） and amoxicillin（AML） are the highest,and the situation of multi-drug resistance is serious.The PFGE have type presented a diverse epidemic pattern.The advantaged bands are less popular than before and there is coexistence for various types.