婴幼儿腹泻感染的非伤寒沙门菌分子分型和耐药情况研究

Molecular subtyping and antibiotic resistance of non-Typhi salmonella isolated from infants

目的研究婴幼儿感染的非伤寒沙门菌的分子流行病学特点和耐药情况。方法收集上海地区腹泻婴幼儿粪便标本,进行沙门菌的分离培养,生化鉴定,血清型分型,分子分型和药物敏感性检测实验。结果 583份婴幼儿粪便中分离出沙门菌共19株,主要为肠炎沙门菌和鼠伤寒沙门菌。肠炎沙门菌脉冲场凝胶电泳(pulsed-field gel electrophoresis,PFGE)带型相似度较高(88.7%),且主要带型为上海近年流行的优势带型。药物敏感性实验结果显示,菌株对测试的15种抗生素的总体耐药率为78.95%(15/19),对萘啶酸(68.42%)和氨苄西林(63.20%)的耐药率较高,对环丙沙星(10.53%)和庆大霉素(10.53%)的耐药率较低,对三代头孢类抗生素的耐药率较高(40%)。菌株耐药谱分布广泛,发现多重耐药菌株13株。结论本研究中,婴幼儿感染的非伤寒沙门菌耐药情况比较严重;不同血清型和分子分型的菌株耐药性差异无统计学意义。

Objective To investigate the molecular characteristics and antibiotic resistance of non-Typhi salmonella isolated from infants. Methods Stool samples were collected from infants with diarrhea in Shanghai to isolate nonTyphi salmonella. The isolated strains’ identification,serotyping,molecular subtyping and drug susceptibility test were conducted Results A total of 19 non-Typhi salmonella strains were isolated from 583 infant stool samples,and the majority were Salmonella enterititis and Salmonella typhimurium strains. The PFGE patterns of Salmonella enterititis strains were similar（88. 7%）,and were the prevalent patterns of the strains isolated in Shanghai in recent years. The drug susceptibility test showed the antibiotic resistance rate of the strains in this study was 78. 95%（15 /19）. The resistance rates to Nalidixic acid（68. 42%）,Ampicillin（63. 20%）,and the third generation Cephalosporins（40%）were higher than those to other antibiotics,and the resistance rates to Ciprofloxacin（ 10. 53%） and Gentamicin（10.53%） were low. In addition,most strains（13） were multidrug resistant. Conclusion The antibiotic resistance of the non-Typhi salmonella isolated from infants with diarrhea was serious,and the differences in drug resistance among the strains with different serotypes and molecular types had no statistical significance.