一起由金黄色葡萄球菌和路邓葡萄球菌引发食物中毒病原分析

目的 通过一起疑似葡萄球菌引发食物中毒进行葡萄球菌肠毒素检测,并结合检测出致病性葡萄球菌病原学分析,为下一步食物中毒处置提供诊断依据。方法 根据流行病学调查和国家标准《食品微生物学检验》GB4789,对可疑食物及患者呕吐物、肛拭子等进行了几种常见致病原菌分离培养,并直接采用实时荧光PCR方法对金黄色葡萄球菌肠毒素A~E基因进行分型,用全自动微生物鉴定分析仪进行系统生化鉴定,并做血浆凝固酶试验。结果 在食用剩余汉堡中分离出1株金黄色葡萄球菌、2名患者肛拭子中分离出2株金黄色葡萄球菌,1名患者呕吐物中分离1株血浆凝固酶阴性路邓葡萄球菌,利用PCR方法分别对其进行了肠毒素基因分型,结果显示,食用剩余汉堡中1株和2株患者肛拭子的金黄色葡萄球菌肠毒素均为SEA型,为同一型;1株患者呕吐物的路邓葡萄球菌的肠毒素为SEC型。 结论 该起食物中毒主要是由金黄色葡萄球菌产生SEA型肠毒素所导致,血浆凝固阴性路邓葡萄球菌跟金黄色葡萄球菌一样,也能产生肠毒素同样具有致病性作用,提示路邓葡萄球菌不单纯只是人类皮肤共生菌,或许还跟金黄色葡萄球菌同样具有侵袭性、产肠毒素等致病性,在进行公共卫生流行调查诊断时不能被忽视。

Pathogenic analysis of a case of food poisoning caused by Staphylococcus aureus and Staphylococcus lugdunensis

Objective To detect staphylococcal enterotoxin in a case of suspected staphylococcal food poisoning, and to analyze the etiology of pathogenic staphylococcal bacteria, so as to provide diagnostic basis for the next management of food poisoning. Methods According to the epidemiological investigation and the national standard "food microbiology test" GB4789. Several common pathogenic bacteria were isolated and cultured from suspicious food, vomit and anal swabs of patients, and real-time fluorescent PCR was used to classify the A-E genes of Staphylococcus aureus enterotoxin, automatic bacterial identification instrument and plasma coagulase. Results One strain of Staphylococcus aureus was isolated from the leftover hamburgers, two strains of Staphylococcus aureus were isolated from the anal swabs of two patients, and one strain of plasma coagulase-negative Staphylococcus lugdunensis was isolated from the vomit of one patient. The enterotoxin genotyping was conducted by PCR method, and the results showed that Staphylococcus aureus enterotoxin in the anal swabs of the patients with 1 and 2 strains from the remaining hamburgers were of the same type and SEA type. The enterotoxin of 1 strain of Staphylococcus lugdunensis in patient's vomit was SEC type. Conclusions The food poisoning is mainly produced by Staphylococcus aureus enterotoxin SEA type, but it should be noted that plasma coagulation-negative Staphylococcus lugdunensis, liks Staphylococcus aureus, also can produce enterotoxin with pathogenic effect. Staphylococcus lugdunensis is not just human skin symbiotic bacteria, but also be as invasive and enterotoxins as Staphylococcus aureus. We cannot ignore it when conducting public health epidemiological investigations and diagnoses so that we can be concerned when similar events occur in the future.