Dinko Bismarck, Ayivor-Djanie Reuben, Abugri James, Agboli Eric, Kye-Duodu Gideon, Tagboto Senyo, Tampuori John, Adzaku Festus, Binka Fred N, Awandare Gordon A
Department of Biomedical Sciences, School of Basic and Biomedical Sciences, University of Health and Allied Sciences, Ho, Ghana.
Department of Biochemistry, Cell and Molecular Biology, University of Ghana, Legon, Accra, Ghana.
Malariaworld J. 2016 Jun 10;7:5. doi: 10.5281/zenodo.10797112. eCollection 2016.
Rapid diagnostic tests (RDTs) and microscopy are routinely used for the diagnosis of malaria in Ghana. DNA-based polymerase chain reaction (PCR) is not yet used routinely. We compared diagnostic methods and tested the sensitivities of different malaria diagnostic methods against PCR.
Study participants from four hospitals with a suspicion of malaria donated finger -prick blood for RDT and blood film examination. In addition, a blood spot was collected for PCR analysis, prior to treatment. Retrospective species-specific PCR was performed on all samples collected.
Using PCR we found an overall malaria prevalence of 39% among the 211 evaluable blood spots (83/211) and this ranged between 6-61% across the four hospitals. Of the 164 participants with RDT data, malaria prevalence was 57% (94/164), ranging from 3-100% from the four hospitals. Microscopy was the least sensitive with a parasite prevalence of 21% (25/119) of the evaluable 119 participants, varying from 9 to 35% across three health facilities. By comparison, we found the sensitivities and specificities of RDT results when compared to PCR to be slightly higher than microscopy compared to PCR. These were 56.4% versus 41.7% and 90% versus 81.9%, respectively, but generally lower than expected. Ninety-five percent of the PCR-detected infections were , while 4% were mixed species infections of and , with the remaining being a mono-infection of .
While using PCR as a gold standard, we found RDT to be more reliable in diagnosing malaria than microscopy. In addition, a majority of malaria-treated cases were not supported by PCR diagnosis, leading to possible overtreatment. Pragmatic strategies are needed to ensure suspected malaria cases are accurately diagnosed before treatment.
快速诊断检测（RDTs）和显微镜检查在加纳被常规用于疟疾诊断。基于DNA的聚合酶链反应（PCR）尚未被常规使用。我们比较了诊断方法，并针对PCR测试了不同疟疾诊断方法的敏感性。
来自四家怀疑患有疟疾医院的研究参与者捐赠指尖血用于RDT和血涂片检查。此外，在治疗前采集血斑用于PCR分析。对所有采集的样本进行回顾性物种特异性PCR。
使用PCR我们在211个可评估血斑中发现总体疟疾患病率为39%（83/211），四家医院的患病率在6%-61%之间。在164名有RDT数据的参与者中，疟疾患病率为57%（94/164），四家医院的患病率在3%-100%之间。显微镜检查的敏感性最低，在119名可评估参与者中寄生虫患病率为21%（25/119），三个卫生机构的患病率在9%-35%之间。相比之下，我们发现与PCR相比，RDT结果的敏感性和特异性略高于显微镜检查与PCR相比的结果。分别为56.4%对41.7%以及90%对81.9%，但总体低于预期。PCR检测到的感染中有95%为 ，而4%为 和 的混合物种感染，其余为 的单一感染。
以PCR作为金标准时，我们发现RDT在诊断疟疾方面比显微镜检查更可靠。此外，大多数接受疟疾治疗的病例未得到PCR诊断的支持，导致可能存在过度治疗。需要采取务实策略以确保疑似疟疾病例在治疗前得到准确诊断。
