聚合酶链反应技术与镜检法诊断间日疟的对比研究

COMPARISON OF PCR AND MICROSCOPICAL METHOD FOR DETECTION OF PLASMODIUM VIVAX

目的 评价聚合酶链反应技术在间日疟诊断中的应用价值。 方法 根据红内期疟原虫 SSUr RNA编码基因序列 ,设计合成 1对引物 ,采用聚合酶链反应技术 ,扩增检测“四热”病人血样中间日疟原虫 DNA;同时作厚血膜镜检疟原虫。 结果 从间日疟患者血样中扩增出 341bp的 DNA片段 ,与预期的扩增片段大小相符 ,而正常人血样及空白对照无特异性条带 ;对于 2 34份“四热”病人血样 ,PCR法检出 16份阳性 ,阳性率为 6 .8% ;厚血膜镜检 13份阳性 ,阳性率为 5 .6 % ;两种方法相比差异无显著性 (P>0 .0 5 ) ;对于 3份 PCR阳性而镜检法阴性的血样 ,重新作 PCR,结果仍然为阳性。以镜检法为标准 ,PCR法的灵敏度为 10 0 % ,特异度为 98.6 %。 结论 PCR技术灵敏特异 ,可替代镜检法用于间日疟感染的临床及现场检测。

Objective To evaluate the application value of PCR based method in diagnosis of vivax malaria. Methods A pair of primers was synthesized for PCR amplification of DNA of Plasmodium vivax according to the SSUrRNA gene, and 324 blood samples of patients with fever syndrome were collected from primary medical units in Shenzhen, P. R. China. For each sample, microscopic examination of Giemsa stained thick films and PCR based method were carried out for detection of P. vivax . Results The positive rate of PCR method and microscopical assay were 6.8%(16/234) and 5.6%(13/234) respectively. Considering the results of microscopic examination as a standard, the sensitivity of PCR method was 100%, and the specificity was 98.6%. By statistical analysis, there was not significant difference between the two methods( P >0.05). Conclusion The established PCR method was specific and sensitive, which may be a good alternative of microscopic method for diagnosis of vivax malaria.