贵港市沙门菌血清型、耐药性及PFGE分型特征研究

Study on the serotype,drug resistance,and PFGE typing characteristics of Salmonella in Guigang city

目的了解2021年贵港市哨点医院腹泻患者中沙门菌血清型分布、脉冲场凝胶电泳(PFGE)分型特征、对抗生素的耐药情况以及腹泻患者(患者株)与生鲜猪肉(猪肉株)中鼠伤寒沙门菌的同源性。方法对110株患者株与100株猪肉株沙门菌进行血清学分型鉴定,采用微量肉汤稀释法对患者株进行15种药物敏感试验,并应用PFGE对腹泻患者的110株沙门菌、生鲜猪肉中分离出的鼠伤寒沙门菌进行指纹图谱分析。结果患者株中共分离出12个血清型,鼠伤寒沙门菌和肠炎沙门菌为优势菌,所占比例分别为62.73%和9.09%;猪肉株中占比最高的也是鼠伤寒沙门菌,共40株(40.00%)。患者株普遍耐药,耐药菌株占比为91.82%,对氨苄西林的耐药率最高(88.18%);多重耐药率高达83.64%。患者株可分为73种PFGE带型,有13种带型各包含2~6株相同带型;患者株与猪肉株间鼠伤寒沙门菌PFGE条带相似度为53.8%~100.0%,含5组大的克隆群,每组克隆群均含有患者株和猪肉株。结论贵港市哨点医院腹泻患者中鼠伤寒沙门菌所占比例相对较高;沙门菌耐药较为严重;PFGE指纹图谱具有多样性,存在可能由散发的沙门菌引起食物中毒的风险,提示猪肉中的鼠伤寒沙门菌和该市沙门菌散发病例有一定的关联。

Objective To understand the distribution of Salmonella serotypes,PFGE(Pulsed Field Gel Electrophoresis)typing characteristics,and antibiotics resistance among diarrhea patients,and the homology of Salmonella typhimurium between diarrhea patients(patient strains)and fresh pork(pork strains)in sentinel hospitals in Guigang city in 2021.Methods Serological identification of 110 patient strains and 100 pork strains of Salmonella.Fifteen types of drug sensitivity tests were carried out on patient strains by micro broth dilution method.Fingerprint analysis of 110 strains of Salmonella isolated from diarrhea patients,and Salmonella typhimurium isolated from fresh pork by Pulsed Field Gel Electrophoresis.Results A total of 12 serotypes were isolated from the patient strains,and Salmonella typhimurium and Salmonella enteritidis were the dominant bacteria,accounting for 62.73%and 9.09%respectively.Salmonella typhimurium was accounted for the highest proportion among pork strains,with a total of 40 strains(40.00%).The patient strains were generally drug-resistant,and the drug-resistant strains accounted for 91.82%.The drug-resistant rate to ampicillin was the highest(88.18%),and the multi-drug resistance rate was as high as 83.64%.The patient strains were divided into 73 types of PFGE band patterns,in which 21 band types each contained 2 to 6 strains of same band types.The similarity of Salmonella typhimurium PFGE bands between patient strains and pork strains was 53.8%-100.0%,and there were 5 large clonal groups,each of which contained both patient strains and pork strains.Conclusions The proportion of Salmonella typhimurium in diarrhea patients in sentinel hospitals in Guigang city is relatively high.Salmonella drug resistance is relatively serious,and PFGE fingerprints are diverse.There is a risk of food poisoning caused by sporadic Salmonella,suggesting that there is a certain relationship between Salmonella typhimurium in pork and sporadic cases of Salmonella in this city.