Center for Global Health and Diseases, School of Medicine, Case Western Reserve University, Cleveland, Ohio.
Nuffield Department of Medicine, Oxford Big Data Institute, University of Oxford, Oxford, United Kingdom.
Am J Trop Med Hyg. 2018 Jun;98(6):1683-1691. doi: 10.4269/ajtmh.17-0845. Epub 2018 Mar 15.
histidine-rich protein 2 (PfHRP2) forms the basis of many current malaria rapid diagnostic tests (RDTs). However, the parasites lacking part or all of the gene do not express the PfHRP2 protein and are, therefore, not identifiable by PfHRP2-detecting RDTs. We evaluated the performance of the SD Bioline Malaria Ag P.f/Pan RDT together with variation in Madagascar. Genomic DNA isolated from 260 patient blood samples were polymerase chain reaction (PCR)-amplified for the parasite 18S rRNA and genes. Post-PCR ligation detection reaction-fluorescent microsphere assay (LDR-FMA) was performed for the identification of parasite species. histidine-rich protein 2 amplicons were sequenced. Polymerase chain reaction diagnosis of patient samples showed that 29% (75/260) were infected and was present in 95% (71/75) of these PCR-positive samples. Comparing RDT and detection by LDR-FMA, eight samples were RDT negative but positive (false negatives), all of which were positive. The sensitivity and specificity of the RDT were 87% and 90%, respectively. Seventy-three samples were amplified for , from which nine randomly selected amplicons were sequenced, yielding 13 sequences. Amplification of , combined with RDT analysis and detection by LDR-FMA, showed that there was no indication of deletion. Sequence analysis of showed that the correlation between sequence structure and RDT detection rates was unclear. Although the observed absence of deletion from the samples screened here is encouraging, continued monitoring of the efficacy of the SD Bioline Malaria Ag P.f/Pan RDT for malaria diagnosis in Madagascar is warranted.
组氨酸丰富蛋白 2（PfHRP2）是许多当前疟疾快速诊断测试（RDT）的基础。然而，缺乏部分或全部 基因的寄生虫不会表达 PfHRP2 蛋白，因此无法被 PfHRP2 检测 RDT 识别。我们评估了 SD Bioline 疟疾 Ag P.f/Pan RDT 的性能，并结合马达加斯加的变异情况进行了评估。从 260 份患者血液样本中提取基因组 DNA，用聚合酶链反应（PCR）扩增寄生虫 18S rRNA 和 基因。进行聚合酶链反应后连接检测反应-荧光微球分析（LDR-FMA），以鉴定寄生虫种类。对 PfHRP2 扩增子进行测序。对患者样本进行 PCR 诊断显示，29%（75/260）感染，这些 PCR 阳性样本中有 95%（71/75）存在 。比较 RDT 和 LDR-FMA 检测，有 8 个样本 RDT 阴性但 LDR-FMA 阳性（假阴性），均为 阳性。RDT 的敏感性和特异性分别为 87%和 90%。对 73 个样本进行了 扩增，从中随机选择 9 个扩增子进行测序，得到 13 个序列。结合 RDT 分析和 LDR-FMA 检测 扩增，表明没有迹象表明 缺失。对 序列分析表明，序列结构与 RDT 检测率之间的相关性尚不清楚。尽管这里筛选的样本没有观察到 缺失，但仍需要继续监测 SD Bioline 疟疾 Ag P.f/Pan RDT 在马达加斯加进行疟疾诊断的疗效。
