苏州市一起疑似类志贺邻单胞菌引起的食物中毒调查与分析

Investigation and analysis of a suspected food poisoning caused by Pseudomonas shigelloides in Suzhou city

目的分析2019年6月苏州市某幼儿园食物中毒的原因,了解病原菌的基因分型和耐药谱情况。方法通过问卷调查、电话访谈,查阅医院就诊记录、餐厅订餐记录等主动搜索病例,开展病例个案调查和现场卫生学调查,采集相关样品进行实验室检测。以分离培养,质谱快速鉴定,VITEK-2 Compact全自动细菌鉴定仪生化鉴定进行鉴定分析,脉冲场电泳(pulsed-field gel electrophoresis,PFGE)进行基因分型,药敏试验采用微量肉汤稀释法。结果共搜索到17位病例(包括确诊病例4人),临床表现为腹痛、腹泻等胃肠道不适症状,均无头痛、发热等其他不适症状。6月20日中餐为可疑餐次,此外无其他共同饮食史。现场共采集47份样本(包括菜品、环境样本和肛拭子),其中4份学生肛拭子检出类志贺邻单胞菌。PFGE分型结果显示其中3株菌100%同源,属于同一型别,另一株菌与其差异较大,属于不同型别。对14种抗生素的药敏分析显示,3株菌(同一型别)除对氨苄西林耐药外还对甲氧苄胺嘧啶/磺胺甲噁唑耐药,对其它抗生素均敏感。另1株菌对氨苄西林耐药,对其它抗生素均敏感。结论此次事件很可能是一起由类志贺邻单胞菌引起的食物中毒,并且可能来源于不同的传染源。

Objective To analyze me causes of food poisoning in a Kinaergarten in suzhou city in June 2019,and to understand the genotype and drug resistance spectrum of pathogenic bacteria.Methods The case investigations and on-site hygiene surveys were carried out by actively searching for cases through questionnaires,telephone interviews,consulting hospital visit records and restaurant reservation records,etc.Then relevant samples for laboratory testing were collect.Bacterial strains were identified and analyzed through isolation and culture,mass spectrometry for rapid identification,and biochemical identification by vitek-2 Compact automatic bacterial identification instrument,genotyping was carried by pulsed-field gel electrophoresis(PFGE).The antibiotic susceptibility test was carried out by microbroth dilution method.Results A total of 17 cases(including 4 confirmed cases)were found.The clinical manifestations were gastrointestinal discomfort symptoms such as abdominal pain and diarrhea,without headache,fever and other discomfort symptoms.Lunch on June 20 was a suspicious meal and there was no other shared dietary history.A total of 47 samples(including dishes,environment samples and anal swabs)were collected,and 4 students’anal swabs were found to contain Pseudomonas shigelloides.PFGE typing results showed that the three strains were 100%homologous and belonged to the same type.The other strain was quite different and belongs to a different type.Drug susceptibility analysis of 14 antibiotics showed that three strains(same type)were trimethoprim/sulfamethoxazole in addition to being resistant to ampicillin,and were sensitive to other antibiotics.The other strain was resistant toresistant to ampicillin and sensitive to other antibiotics.Conclusion This incident is most likely a case of food poisoning caused by Pseudomonas shigelloides and may originate from different sources of infection.