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目的:了解北京市肯塔基沙门菌临床分离株的流行情况、耐药水平及分子特征。方法:对2010-2020年分离的22株肯塔基沙门菌采用微量肉汤稀释法进行抗生素药物敏感性检测；全基因组测序进行多位点序列分型、基因组岛和耐药基因识别。采用PFGE分析菌株的分子流行病学特征。结果:22株菌对8~22种抗生素耐药，尤其是对环丙沙星、阿奇霉素和头孢菌素类等都表现为超高水平的多重耐药。21株菌超广谱β-内酰胺酶表型阳性。全基因组序列分析显示，22株肯塔基沙门菌均为ST198，携带SGI1-K基因组岛。所有菌株均有耐药基因n tetA、n sul1、n qacE，喹诺酮耐药决定区n gyrA基因存在2个突变位点（S83F、D87 N）、n parC基因存在3个突变位点（T57S、S80I、T255S）。β-内酰胺类相关耐药基因（n blaCTX-M-55、n blaCTX-M-14b、n blaTEM-141、n blaTEM-206、n blaTEM-209、n blaTEM-214、n blaTEM-1B）、氨基糖甙类耐药相关基因［n aac（3）n -Id、n aac（3）n -IId、n aac（6'）n -Iaa、n aadA7、n aadA17、n aph（3'）-n Ia、n aph（3''）-n Ib、n aph（6）-Id、n rmtB］以及n floR、n dfrA14、n mphA和n qnrS1等基因在不同年代菌株间存在明显差异。PFGE图谱分析显示，22株菌株之间相似性>85%，与全球广泛传播的ST198-X1流行株高度同源，在传播扩散过程中，耐药谱和PFGE图谱都发生了变化，分为两大聚类簇。n 结论:北京市流行的肯塔基沙门菌为多重耐药的ST198-X1-SGI-1K国际流行株，自2016年以来保持低水平流行，引起散发感染病例和聚集性腹泻事件。对氟喹诺酮类、ESBL和阿奇霉素等耐药严重，应加强多重耐药肯塔基沙门菌的监测。“,”Objective:To investigate the epidemiological, drug resistance and molecular characteristics of n Salmonella (n S.) Kentucky strains isolated from diarrheal patients in Beijing.n Methods:The drug susceptibility of 22 n S. Kentucky strains isolated in Beijing during 2010-2020 was tested by using the micro broth dilution method. The multilocus sequence typing (MLST), drug resistance genes and n Salmonella genomic island (SGI) identifications of the strains were performed by whole-genome sequencing (WGS).The pulsed field gel electrophoresis (PFGE) was performed to analyze the molecular epidemiological characteristics of the isolates.n Results:The 22 strains were highly resistant to 8-22 kinds of antibiotics, especially to ciprofloxacin, cephalosporins and azithromycin, n etc., showing a super high level of multidrug resistance and 21 strains were positive for extended-spetrum beta-lactamase (ESBL). The WGS analysis revealed that all the isolates belonged to ST198, carrying SGI1-K. The drug resistance genes n tetA, n sul1 and n qacE were identified in all strains and Quinolone resistance-determining regions (QRDRs) showed 2 mutations in n gyrA (S83F, D87 N) and 3 mutations in the n parC gene (T57S, S80I, T255S). The resistance genes associated with n β-lactam antibiotics (n blaCTX-M-55, n blaCTX-M-14b, n blaTEM-141, n blaTEM-206, n blaTEM-209, n blaTEM-214, n blaTEM-1B), resistance genes associated with aminoglycosides [n aac(3)-Id, n aac(3)-IId, n aac(6')-Iaa, n aadA7, n aadA17, n aph(3')-n Ia, n aph(3'')-n Ib, n aph(6)-n Id,n rmtB] as well as n floR, n dfrA14,n mphA and n qnrS1 had significant differences in the strains of different years, which were highly consistent with the drug-resistant phenotype. Furthermore, phylogenetic analysis showed that the similarity of the 22 strains was more than 85%, and the strains were highly homologous to CIP-resistant ST198-X1 circulating in the world. In the process of spread, the drug resistance and PFGE spectrums had changed, two clusters had formed.n Conclusions:The n S. Kentucky strains isolated in Beijing shared high homology with the multidrug-resistant strain ST198-X1-SGI-1K isolated in the world, which has maintained a low level of spread since 2016, causing sporadic infections and clusters of diarrhea, and has serious resistances to fluoroquinolones, ESBLs and azithromycin. The surveillance for multidrug-resistant n S. Kentucky should be strengthened.n