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目的：分析江苏省2010年宋内志贺菌的整合子分布及分子分型特征。方法对江苏省2010年分离的33株宋内志贺菌采用 K-B 纸片法检测抗菌药物敏感性，联合 PCR 和限制性片段多态性（RFLP）进行整合子分类和可变区检测，利用测序技术判断整合子可变区耐药基因，应用脉冲场凝胶电泳（PFGE）进行分子同源性分析。结果宋内志贺菌多重耐药率为63.64％，对复方新诺明、四环素、萘啶酸和氨苄西林耐药率较高，分别为84.85％、75.76％、66.67％和63.64％。33株宋内志贺菌中51.52％的菌株检出 I 类整合子，其中4株可变区阳性，携带 dfrA17-aadA5基因盒；81.82％的菌株检出 II 类整合子，携带 dfrA1-sat1-aadA1基因盒；两类整合子同时存在时耐药性更为显著。PFGE 图谱分为13个不同带型，同一带型菌株大多分散于江苏各地。结论整合子在宋内志贺菌中广泛存在，参与其多重耐药机制。多重耐药性在不同地区、不同克隆的菌株间扩散传播。“,”Objective To investigate integron distribution and molecular epidemiological characteristics of Shigella sonnei i-solates in Jiangsu Province in 2010.Methods A total of 33 Shigella sonnei isolates in Jiangsu Province in 2010 were examined for antibiotic susceptibility by Kirby-Bauer (K-B)test.PCR-restriction fragment length polymorphism (RFLP)was performed for integron classification and variable region analysis.DNA sequencing was used to determine drug-resistant gene cassettes in integron variable regions.Pulsed field gel electrophoresis (PFGE)was used for molecular homology analysis.Results Multi-drug resistance rate was 63.64% among Shigella sonnei isolates.Drug resistant rates to sulfamethoxazole (84.85%),tetracy-cline (75.76%),nalidixic acid(66.67%)and ampicillin (63.64%)was relatively high.Among 33 Shigella sonnei isolates, 51.52% strains contained class I integron,among which 4 strains were positive for variable regions,carrying dfrA17-aadA5 gene cassette;81.82% strains contained class II integron,carrying dfrA1-sat1-aadA1 gene cassette.Multi-drug resistance rate of Shigella sonnei isolates increased significantly on the presence of above 2 classes of integrons.A total of 13 PFGE patterns were detected among 33 Shigella sonnei isolates,strains with same PFGE pattern were distributed in different cities of Jiangsu Province.Conclusion Presence of integron was common among Shigella sonnei isolates,which contributed to their multidrug resistance.Multidrug resistance spreaded among Shigella sonnei strains from different regions and different clones.