用于疟疾检测的高通量环介导等温扩增技术的开发及临床性能

Development and clinical performance of high throughput loop-mediated isothermal amplification for detection of malaria.

作者信息

Perera Rushini S, Ding Xavier C, Tully Frank, Oliver James, Bright Nigel, Bell David, Chiodini Peter L, Gonzalez Iveth J, Polley Spencer D

机构信息

Department of Clinical Parasitology, Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, Mortimer Market, London, United Kingdom.

FIND CH-1202 Geneva, Switzerland.

出版信息

PLoS One. 2017 Feb 6;12(2):e0171126. doi: 10.1371/journal.pone.0171126. eCollection 2017.

BACKGROUND

Accurate and efficient detection of sub-microscopic malaria infections is crucial for enabling rapid treatment and interruption of transmission. Commercially available malaria LAMP kits have excellent diagnostic performance, though throughput is limited by the need to prepare samples individually. Here, we evaluate the clinical performance of a newly developed high throughput (HTP) sample processing system for use in conjunction with the Eiken malaria LAMP kit.

METHODS

The HTP system utilised dried blood spots (DBS) and liquid whole blood (WB), with parallel sample processing of 94 samples per run. The system was evaluated using 699 samples of known infection status pre-determined by gold standard nested PCR.

RESULTS

The sensitivity and specificity of WB-HTP-LAMP was 98.6% (95% CI, 95.7-100), and 99.7% (95% CI, 99.2-100); sensitivity of DBS-HTP-LAMP was 97.1% (95% CI, 93.1-100), and specificity 100% against PCR. At parasite densities greater or equal to 2 parasites/μL, WB and DBS HTP-LAMP showed 100% sensitivity and specificity against PCR. At densities less than 2 p/μL, WB-HTP-LAMP sensitivity was 88.9% (95% CI, 77.1-100) and specificity was 99.7% (95% CI, 99.2-100); sensitivity and specificity of DBS-HTP-LAMP was 77.8% (95% CI, 54.3-99.5) and 100% respectively.

CONCLUSIONS

The HTP-LAMP system is a highly sensitive diagnostic test, with the potential to allow large scale population screening in malaria elimination campaigns.

背景

准确、高效地检测亚显微疟原虫感染对于实现快速治疗和阻断传播至关重要。市售的疟疾环介导等温扩增（LAMP）试剂盒具有出色的诊断性能，不过由于需要单独制备样本，其通量受到限制。在此，我们评估一种新开发的高通量（HTP）样本处理系统与荣研疟疾LAMP试剂盒联合使用时的临床性能。

方法

HTP系统使用干血斑（DBS）和液体全血（WB），每次运行可并行处理94个样本。该系统使用699份已知感染状态的样本进行评估，这些样本的感染状态预先通过金标准巢式聚合酶链反应（PCR）确定。

结果

WB-HTP-LAMP的灵敏度和特异性分别为98.6%（95%置信区间[CI]，95.7 - 100）和99.7%（95% CI，99.2 - 100）；DBS-HTP-LAMP的灵敏度为97.1%（95% CI，93.1 - 100），与PCR相比特异性为100%。在疟原虫密度大于或等于2个疟原虫/微升时，WB和DBS HTP-LAMP对PCR的灵敏度和特异性均为100%。在密度小于2个/微升时，WB-HTP-LAMP的灵敏度为88.9%（95% CI，77.1 - 100），特异性为99.7%（95% CI，99.2 - 100）；DBS-HTP-LAMP的灵敏度和特异性分别为77.8%（95% CI，54.3 - 99.5）和100%。