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目的:比较百日咳鲍特菌耐药株与敏感株的基因型别，分析百日咳菌株耐药性演变与分子型别特征的关联性。方法:于2016—2018年在监测医院和社区采集<1岁临床疑似百日咳患儿的鼻咽拭子，采用E-test法检测分离的百日咳鲍特菌对红霉素的耐药性，扩增23S rRNA基因并测序检测其2047位点耐药突变；采用多位点抗原序列分型(MAST)和多位点可变数目串联重复序列分析(MLVA)方法对菌株进行分型。结果:600份鼻咽拭子标本共分离到34株百日咳鲍特菌，其中28株对红霉素耐药，6株敏感。所有红霉素耐药株均检测到23S rRNA基因A2047G位点突变，细菌基因型均为n prn1/n ptxP1/n ptxA1/n fim3-1/n fim2-1，且MLVA型别识别为MT195、MT55和MT104。6株敏感株均未检测到A2047G位点突变，细菌基因型为n prn9(或n prn2)/n ptxP3/n ptxA1/n fim3-1/n fim2-1，且MLVA型别全部为MT27型。n 结论:百日咳鲍特菌红霉素耐药株与敏感株的分子分型特征不同，红霉素耐药性的获得可能伴随特定分子型别的变化。“,”Objective:To compare the genotypes of erythromycin-resistant and -sensitive n Bordetella pertussis, and analyze the relationship between the evolution of drug resistance and the molecular characteristics of n Bordetella pertussis.n Methods:Nasopharyngeal swabs were collected from patients <1 year old with suspected pertussis infection in the disease monitoring hospitals and community in Xi′an during 2016 to 2018. Erythromycin susceptibility of n Bordetella pertussis isolates was tested by E-test. A fragment of 23S rRNA gene was amplified and sequenced to detect drug resistance mutations at the 2047 site. Genotypes of the isolated strains were analyzed with multilocus antigen sequence typing (MAST) and multiple locus variable-number tandem repeat analysis (MLVA).n Results:A total of 34 n Bordetella pertussis strains were isolated from 600 nasopharyngeal swabs. Among them, 28 were resistant to erythromycin and six were sensitive strains. All erythromycin-resistant strains carried a genetic mutation at the A2047G site in the 23S rRNA gene and belonged to the genotype of n prn1/n ptxP1/n ptxA1/n fim3-1/n fim2-1. Three MLVA types, MT195, MT55 and MT104, were identified in these strains. However, no mutation at the A2047G site was found in the six erythromycin-sensitive strains whose genotypes were n prn9 (or n prn2)/n ptxP3/n ptxA1/n fim3-1/n fim2-1 and MT27.n Conclusions:There were differences between erythromycin-resistant and -sensitive n Bordetella pertussis in genotypes, suggesting that erythromycin resistance might be associated with molecular types.n