阴道毛滴虫双链RNA病毒感染及其对甲硝唑耐药性的影响

Double-stranded RNA viral infection of Trichomonas vaginalis isolates and its effect on the metronidazole resistance of parasites

目的调查河南地区阴道毛滴虫临床分离株阴道毛滴虫病毒感染情况,探索病毒感染对阴道毛滴虫甲硝唑耐药性的影响。方法 TYM(trypticase-yeast extract-maltose)无菌培养基培养阴道毛滴虫临床分离株,达到纯培养后提取虫体总核酸(DNA和RNA),进行1%琼脂糖凝胶电泳分析;连续稀释法测量每株虫体的甲硝唑最小致死浓度。结果对30株阴道毛滴虫总核酸进行电泳,其中6株有5.5 kb双链RNA病毒带,病毒感染率为20.0%。阴道毛滴虫病毒阴性组甲硝唑最小致死浓度为(24.27±20.899)μg/ml,病毒阳性组为(5.68±3.588)μg/ml,差异有统计学意义(t=2.143,P<0.05)。结论河南地区阴道毛滴虫临床分离株中检测到阴道毛滴虫病毒,无阴道毛滴虫病毒寄生的虫体易发生甲硝唑抵抗。

Objective To investigate Trichomonas vaginalis isolates from Henan Province for the presence of T.vaginalis virus（TVV） and analyze the effect of TVV of the metronidazole resistance of T.vaginalis.Methods DNA and RNA were simultaneously extracted after T.vaginalis isolates were grown on TYM（trypticase-yeast extract-maltose） medium and maintained as axenic cultures.Samples were then analyzed on 1% agarose gel.The MLC of metronidazole of T.vaginalis isolates was tested using serial dilution.Results TVV was detected in 6 of 30 T.vaginalis isolates;the rate of TVV infection in T.vaginalis isolates was 20.0%.The MLC of metronidazole against TVV-negative T.vaginalis strains in vitro was（24.27±20.899）μg/ml.This was significantly higher than that against TVV-positive strains（5.68±3.588）μg/ml）,and the difference between the two was statistically significant（t=2.143,P0.05）.Conclusion T.vaginalis virus was detected in T.vaginalis isolates from Henan.T.vaginalis isolates not harboring TVV were more likely to be resistant to metronidazole.