Abstract: Cronobacter is a gram-negative bacterium, and it is the main pathogen that threatens the health of infants and children. In recent years, there have been reports of drug-resistant strains of Cronobacter in dairy products and foods. The emergence of drug-resistant strains poses great challenges for clinical treatment. In order to explore the correlation between PFGE type and drug resistance phenotype, this paper tested 68 strains of Cronobacter sakazakii for antibiotic susceptibility by BD PhoenixTM-100 automatic bacterial identification and drug susceptibility analysis system, and selected a total of 19 antibiotics, and used PFGE for molecular typing. The results showed that: 4 strains of Cronobacter sakazakii were drug-resistant, and the resistance rate was 5.88%. Among them, 3 were resistant to cefazolin, 1 to tetracycline. 18 strains showed intermediary, 16 were intermediary to cefazolin and 2 to chloramphenicol. All strains were sensitive to the remaining 16 antibiotics. 68 strains of Cronobacter sakazakii were divided into 58 PFGE type, of which PT037, PT050, PT054, PT007, PT043 and PT046 contained 4, 3, 3, 2, 2, 2 strains respectively, and the remaining 52 types each contain 1 strain, and the type was more dispersed. 3 strains of cefazolin-resistant strains contained 3 PFGE types, 18 strains of intermediate strains contained 16 PFGE types. The resistance rate of Cronobacter sakazakii food isolates detected in this study was low, and no multidrug-resistant strains were found. There was a high degree of genetic polymorphism, and no significant correlation between PFGE type and drug resistance.

Key words: Cronobacter sakazakii, antibiotic resistance, molecular typing

摘要： 克罗诺杆菌是一种革兰氏阴性菌，是配方粉中威胁婴幼儿健康的主要致病菌。近年来，乳制品及食品中常有克罗诺杆菌耐药株的报道，耐药株的出现给临床治疗带来巨大挑战。为探究PFGE型别与耐药表型之间的关联性，采用BD PhoenixTM-100全自动细菌鉴定及药敏系统对食品分离的68株阪崎克罗诺杆菌进行药敏检测，共选择19种抗生素，并采用PFGE对其进行分子分型。结果表明：4株阪崎克罗诺杆菌具有耐药性，耐药率为5.88%。其中，3株对头孢唑啉耐药，1株对四环素耐药。18株菌表现为中介，其中16株对头孢唑啉中介，2株对氯霉素中介。所有菌株对其余16种抗生素均敏感。68株阪崎克罗诺杆菌可分成58个PFGE带型，其中PT037、PT050、PT054、PT007、PT043及PT046带型分别含有4、3、3、2、2、2株菌，其余52个带型各含1株菌，带型较分散。3株头孢唑啉耐药菌株包含3个PFGE带型，18株中介菌株包含16个PFGE带型。检测的阪崎克罗诺杆菌食品分离株耐药率较低，未发现多重耐药菌株，且呈现出高度基因多态性，菌株PFGE带型与耐药性之间无明显相关性。

关键词: 阪崎克罗诺杆菌, 耐药性, 分子分型