鲍曼不动杆菌IRS-PCR基因分型研究

目的 用低频限制性位点聚合酶链反应(IRS-PCR)对鲍曼不动杆菌进行基因分型,分析基因型与鲍曼不动杆菌耐药谱的关系,并初步探讨其在分子流行病学中的作用.方法 随机收集2008年8月至2009年8月临床分离的73株鲍曼不动杆菌,采用K-B法进行药物敏感试验确定鲍曼不动杆菌耐药谱；同时利用IRS-PCR对此73株鲍曼不动杆菌进行基因分型；并分析IRS-PCR分型与鲍曼不动耐药谱的关系；结合IRS-PCR分型结果与73株鲍曼不动杆菌感染病例的临床资料,分析在此时间段鲍曼不动杆菌在我院流行感染的情况.结果 药物敏感试验将73株鲍曼不动杆菌菌株分为A1(19株全耐药型)和A2 ～ A31(54株耐药谱型)31个药敏谱.IRS-PCR法将其分为A～W共23个基因型,其中A、C、B、D和E型为5种优势菌株,分别为14、11、10、8和6株.对比研究发现A1型菌株(15/19)主要集中在基因型A、C、D内,而基因型B包含A15型耐药菌株9株(69.2％),基因型E包含A3型耐药菌株3株(42.9％).A基因型在院内特别是ICU中心引起2次爆发流行,而C和D型主要在呼吸内科引起感染.结论 IRS-PCR基因分型与药敏分型有较高的一致性,且IRS-PCR基因分型在早期发现和预防感染暴发流行方面优于药敏分型.

Genotyping of Acinetobacter baumannii using infrequent-restriction-site polymerase chain reaction(IRS-PCR) techinique

Objective To type Acinetobacter baumannii using infrequent-restriction-site polymerase chain reaction(IRS-PCR) technique and analyze the relationship between the genotype and the drug-resistant spectrum,and preliminarily investigate its role in the prevalence of Acinetobacter baumannii in the clinical sections.Methods 73 strains Acinetobacter baumannii were collected randomly from the Second Xiangya Hospital during Auguest 2008 to Auguest 2009.The K-B method was used to establish resistance spectrum.At the same time,the genotype was determined with IRS-PCR techinique.Then we compared IRS-PCR technique and drug sensitivity test.Combined the results of IRS-PCR genotypes with the infected cases,we investigated the infection and prevalence of Acinetobacter baumannii in the clinical sections.Results 73 strains Acinetobacter baumannii were divided into 31 types including A1(19 strains Pan-drug resistances) and A2-A31(54 strain resistances) according to the results of drug sensitivity test.23 types(A-W) were separated using IRS-PCR,and types of A(14),C(11),B(10),D(8) and E(6) were the predominant types.15 of the 19 A1 strains were distributed in the genotypes of A,C and D.B genotype contained 9 A15 strains(69.2%),and genotype E containd 3 A3 strains(42.9%).Genotype A caused twice infection and prevalence which mainly happened in the intensive care unit(ICU).Furthermore,the prevalence of genotypes C and D were mainly in Department of Respiratory Medicine.Conclusion There is a higher correlation between drug-resistance and IRS-PCR genetypes,and IRS-PCR technique is prior to the antimicrobial susceptibility test in the early detection and prevention of outbreak of infection.