淋病奈瑟菌对头孢曲松的敏感性和porB基因特征分析

Susceptibility of Ceftriaxone Against Neisseria Gonorrhoeae and The porB Gene Mutation Analysis

目的:了解某院分离出的淋病奈悬菌对头孢曲松的敏感性和PorB基因突变特征。方法:收集2019~2021年检出的共43株淋病奈瑟菌,并测定头孢曲松的最低抑菌浓度(minimal inhibitory concent ration,MIC),利用聚合酶链式反应(polymerase chain reaction,PCR),扩增细菌的porB基固,对PCR产物进行Sanger测序,分析淋病奈瑟菌的PorB基因的突变情况。结果:43株菌株主要来自妇科、男科和泌尿外科门诊就诊患者的分泌物或脓液经培养鉴定所得,其中患者男36例(占83.7%)、女7例(占16.3%)。43株菌株均未发现对头孢曲松不敏感的情况。其中MIC≥0.031μg/mL的菌株有10株,占比23.3%。将MIC≥0.031μg/mL菌株进行porB基图的PCR扩增和测序分析显示,其中1栋菌株为PorB1a型;其余9株菌株为DorB1b型,与野生型菌株相比,这9株菌林在G120和/或A121的位置上共发现4种突变方式,分别为G120K/A121D(n=3)、G120K/A121N(n=3)、G120K/A121G(n=2)和G120R/A121D(n=1)。结论:POIB序列分析可以作为区分淋病奈瑟菌及其流行病学初步分析的有用工具之一。头孢曲松仍是治疗淋病奈瑟菌的有效抗生素。

Objective:To investigate the susceptibility of Ceftriaxone and the porB gene mutation characteristics of Neisseria go-norrhoeae which were detected in a hospital Methods:A total of 43 Neisseria gonorrhoeae isolates were collected from the department of Andrologic,Gynaecology and Urology between 2019-2021 years with 36 male patients(83.7%)and 7 female patients(16.3%).The minimal inhibitory concentration(MIC)of ceftriaxone was determined.PCR and sequencing were used to characterize the mutations of the porB gene.Results:ALL isolates were sensitive to ceftriaxone.The proportion of the strains with MIC&0.031 pg/mL was 233%.The porB gene with MIO0.031 pg/mL strains were amplified by PCR and sequenced.One strain was porBla genotype and the other nine strains were porBlb genotype.Compared with the wild-type sequence,porB protein sequences were found four modes of substitution mutation in G120 and A121 in the porBlb genotype strains,namely G120K/A121D(N=3),G120K/A121N(N=3),G120K/A121G(N=2)and G120R/A121D(N=1).Conclusion:PorB dna sequence typing was sufficiently discriminatory for differentiating N.gonorrhoeae isolates and was congruent with epidemiological linkages.Ceftriaxone could still be the first choice in the treatment of Neisseria gonorrhoeae infection.