解脲脲原体对红霉素体外耐药性与ermB基因相关性研究

目的 探讨解脲脲原体(Uu)临床株对红霉素体外耐药性与ermB耐药基因之间的关系.方法 采用微量肉汤稀释法体外测定143株临床分离的Uu对红霉素的最低抑菌浓度(MIC),以MIC≥8μg/ml为耐药判读标准;设计引物扩增ermB基因,并以多条带抗原基因为靶位设计引物对Uu进行生物学分群.结果 Uu对红霉素MIC范围为≤0.125μg/至≥128μg/ml,MIC50为16 μg/ml,MIC90≥128 μg/ml,耐药率为64.38%.ermB基凶总的阳性率为27.97%,主要分布在MIC≥8 μg/ml的菌株.两生物群之间不存在红霉素耐药性及ermB基因阳性率的差异.结论 ermB基因可能是介导Uu对红霉素耐药的基因,两生物群在对红霉素耐药性机制的差异需进一步研究.

Study on the relationship between erythromycin sensitivity and ermB gene in Ureaplasma urealyticum

Objective To study the relationship between erythromyein sensitivity and ermB gene in 143 Ureaplasma urealyticum (Uu) clinical isolates. Methods We detected the minimum inhabit concen-trations (MICs) of Uu to erythromycin by broth dilution method and MIC≥8 μg/ml was used as standard concentration of resistance to erythromycin. Polymerase chain reaction was used to detect the ermB gene and biotype Uu with primers based on multi-band antigen gene. Results The MICs, MIC50 MIC90 of Uu to erythromycin were ≤0. 125 μg/ml to ≥128 μg/ml, 16 μg/ml, and ≥128 μg/ml, respectively, with a high resistance rate of 64.38%. ermB gene, which was mainly detected in Uu with MIC≥8 μg/ml, was positively detected in 40 out of 143 Uu strains (27.97%). No significant differences of the resistance to erythromycin and positive rate of ermB gene were found between the two biovars in the study . Conclusion ermB gene may probably be one of the important genes conferring resistance to erythromycin in Uu. Further studies are needed to discover the difference of resistance and mechanism of erythromycin between the two bi-ovars.