某地不同来源肺炎克雷伯菌的耐药性和分子特征分析

Drug resistance and molecular typing characteristics of Klebsiella pneumoniae in meat food and diarrhea samples in a local area

【目的】了解肉类食品和腹泻样本中分离的肺炎克雷伯菌的药物敏感性和分子分型特征。【方法】对上海市金山区2020—2021年市场随机抽样采集的118份肉类(鸡肉和猪肉)和该区医院门诊1499份腹泻样本分离的71株肺炎克雷伯菌,经鉴定后通过微量肉汤稀释法进行药敏试验,脉冲场凝胶电泳(PFGE)分析其同源性。【结果】肉类食品的肺炎克雷伯菌总体检出率为11.86%(14/118),其中鸡肉检出率20.93%(9/43),高于猪肉检出率6.67%(5/75),不同肉类检出差异有统计学意义(χ^(2)=5.317,P<0.05)。腹泻样本的肺炎克雷伯菌检出率为3.80%(57/1499)。菌株对氨苄西林的耐药率最高,达76.06%。人源肺炎克雷伯菌多重耐药株有5株,占8.77%。食源肺炎克雷伯菌多重耐药株有2株,占14.28%;食源性耐亚胺培南1株。71株肺炎克雷伯菌聚类分析得到70种带型,相似度为39.4%~100.0%,总体呈基因多样性。【结论】金山区食源和腹泻样本中分离的肺炎克雷伯菌多重耐药程度较严重,PFGE带型较分散。建议加强对人群和动物性食品中该病原菌的监测,警惕多重耐药株的出现和食物链传播风险。

[Objective]To determine the drug sensitivity and molecular typing characteristics of Klebsiella pneumoniae isolated from meat and diarrhea samples in a local area.[Methods]Seventy-one strains of K.pneumoniae were isolated from 118 meat food(chicken and pork)randomly sampled in the markets in Jinshan District,Shanghai,2020‒2021,and 1499 diarrhea samples from outpatient diarrhoea patients in hospitals in the same district.Then drug susceptibility testing was conducted by micro-broth dilution method,and sequence identity was determined by pulsed field gel electrophoresis(PFGE).[Results]The overall detection rate of K.pneumoniae in meat was 11.86%(14/118),with detection rate 20.93%(9/43)in chicken and 6.67%(5/75)in pork.The difference in detection between meats was statistically significant(χ^(2)=5.317,P<0.05).The detection rate of K.pneumoniae in diarrhea samples was 3.80%(57/1499).Furthermore,the isolated strains showed the highest resistance to ampicillin at 76.06%.The multi-drug resistant strains included 5 of human origin(8.77%)and 2 of foodborne origin(14.28%).Additionally,1 foodborne imipenem-resistant strain was detected.A total of 71 strains of K.pneumoniae were found to have 70 banding types,with similarity ranging from 39.4%to 100%,suggesting genetic diversity.[Conclusion]K.pneumoniae isolated from foodborne and diarrhea samples showed multi-drug resistance in Jinshan District,.with scattered PFGE banding patterns.It is recommended to strengthen the monitoring of this pathogen in the population and animal food,and be alert to the emerging multi-drug resistant strains and risk of food chain transmission.