Institute of Tropical Medicine, Antwerp, Belgium ; Faculty of Medicine, Kinshasa University, Kinshasa, Democratic Republic of the Congo ; Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of the Congo.
PLoS Negl Trop Dis. 2013 Oct 17;7(10):e2504. doi: 10.1371/journal.pntd.0002504. eCollection 2013.
Molecular methods have great potential for sensitive parasite detection in the diagnosis of human African trypanosomiasis (HAT), but the requirements in terms of laboratory infrastructure limit their use to reference centres. A recently developed assay detects the Trypanozoon repetitive insertion mobile element (RIME) DNA under isothermal amplification conditions and has been transformed into a ready-to-use kit format, the Loopamp Trypanosoma brucei. In this study, we have evaluated the diagnostic performance of the Loopamp Trypanosoma brucei assay (hereafter called LAMP) in confirmed T.b. gambiense HAT patients, HAT suspects and healthy endemic controls from the Democratic Republic of the Congo (DRC).
METHODOLOGY/PRINCIPAL FINDINGS: 142 T.b. gambiense HAT patients, 111 healthy endemic controls and 97 HAT suspects with unconfirmed status were included in this retrospective evaluation. Reference standard tests were parasite detection in blood, lymph or cerebrospinal fluid. Archived DNA from blood of all study participants was analysed in duplicate with LAMP. Sensitivity of LAMP in parasitologically confirmed cases was 87.3% (95% CI 80.9-91.8%) in the first run and 93.0% (95% CI 87.5-96.1%) in the second run. Specificity in healthy controls was 92.8% (95% CI 86.4-96.3%) in the first run and 96.4% (95% CI 91.1-98.6%) in the second run. Reproducibility was excellent with a kappa value of 0.81.
CONCLUSIONS/SIGNIFICANCE: In this laboratory-based study, the Loopamp Trypanosoma brucei Detection Kit showed good diagnostic accuracy and excellent reproducibility. Further studies are needed to assess the feasibility of its routine use for diagnosis of HAT under field conditions.
分子方法在诊断人类非洲锥虫病（HAT）方面具有很高的寄生虫检测敏感性，但实验室基础设施的要求限制了它们在参考中心的使用。最近开发的一种检测方法在等温扩增条件下检测到锥虫重复插入移动元件（RIME）DNA，并已转化为即用型试剂盒格式，即环介导等温扩增检测布鲁氏锥虫（Loopamp Trypanosoma brucei）。在这项研究中，我们评估了环介导等温扩增检测布鲁氏锥虫（Loopamp Trypanosoma brucei）检测试剂盒（简称 LAMP）在刚果民主共和国（DRC）确诊的 T.b. gambiense HAT 患者、HAT 疑似病例和健康地方病对照者中的诊断性能。
方法/主要发现：本回顾性评估纳入了 142 例 T.b. gambiense HAT 患者、111 名健康地方病对照者和 97 名未经证实的 HAT 疑似病例。参考标准检测为血液、淋巴液或脑脊液中的寄生虫检测。所有研究参与者的血液存档 DNA 均用 LAMP 进行了双重分析。在第一轮和第二轮检测中，LAMP 在寄生虫学确诊病例中的敏感性分别为 87.3%（95%CI 80.9-91.8%）和 93.0%（95%CI 87.5-96.1%）。在第一轮和第二轮检测中，LAMP 在健康对照组中的特异性分别为 92.8%（95%CI 86.4-96.3%）和 96.4%（95%CI 91.1-98.6%）。重复性极好，kappa 值为 0.81。
在这项基于实验室的研究中，环介导等温扩增检测布鲁氏锥虫试剂盒显示出良好的诊断准确性和极好的重复性。需要进一步研究来评估其在现场条件下常规用于诊断 HAT 的可行性。
