两种检测方法在间日疟和卵形疟诊断中的应用分析

Analysis on the application of two methods to detection of Plasmodium vivax and Plasmodium ovale

目的分析疟原虫镜检和巢式PCR检测间日疟和卵形疟效果。方法收集2012～2016年输入性间日疟和卵形疟病例血样,巢式PCR检测疟原虫ssRNA基因,并与显微镜检结果进行比对。结果显微镜检和巢式PCR检测71份血样,间日疟、卵形疟、混合感染分别占74.6%、25.4%、0%和63.4%、29.6%、7%,符合率为81.7%;亚洲23份血样,镜检与巢式PCR均为间日疟,符合率为100%,巢式PCR检测非洲血样48份,间日疟、卵形疟和混合感染分别占45.8%、43.8%和10.4%,镜检与巢式PCR符合率为72.9%;巢式PCR检测26份卵形疟,经典curtisi、变种wallikeri和混合感染分别占80.8%、11.5%和7.7%,检出变种wallikeri总数占卵形疟19.2%。结论巢式PCR检测疟原虫虫种鉴别优于传统镜检法,可提高疟疾病例诊断水平。

Objective To assess the outcomes of applying microscopic examination and nested polymerase chain reaction（ PCR） to detection of Plasmodium vivax（ P. vivax） and Plasmodium ovale（ P. ovale）. Methods-Blood samples were collected from patients infected with P. vivax and P. ovale between 2012 and 2016. Nested PCR was performed to determine the Plasmodium ssRNA gene,and the results were compared with microscopic findings. Results A total of 71 blood samples were tested by microscopy and nested PCR. The two techniques revealed simple P. vivax,P. ovale and mixed infection by 74. 6%,25. 4% and 0%,and 63. 4%,29. 6% and7%,respectively. The coincidence rate was 81. 7%. In the 23 blood samples from Asia imported P. vivax cases,the coincidence rate was 100% by microscopic examination and nested PCR. Nested PCR revealed that P. vivax,P. ovale and mixed infection was 45. 8%,43. 8% and 10. 4%,respectively,in the 48 blood samples obtained from Africa imported cases. The coincidence rate was 72. 9% by two techniques. Twenty-six blood samples of P.ovale were tested by nested PCR,the results demonstrated that P. ovale curtisi（ former classic type） and P. ovale wallikeri（ former variant type） and mixed infection was 80. 8%,11. 5% and 7. 7%,respectively,and the total number of mutant wallikeri accounted for 19. 2% of P. ovale. Conclusion Nested PCR is superior to conventional microscopic examination in detection of plasmodium,and can improve the diagnosis of malaria.