PECET-Program for the Study and Control of Tropical Diseases. Faculty of Medicine, Universidad de Antioquia-UdeA, Medellín, Colombia.
Epidemiology and Biostatistic Universidad CES, Medellín, Colombia.
Trans R Soc Trop Med Hyg. 2021 Dec 2;115(12):1427-1433. doi: 10.1093/trstmh/trab073.
The diagnosis of cutaneous leishmaniasis (CL) is based on demonstration of the presence of the parasite in samples obtained from the lesions by direct examination (DE), culture or polymerase chain reaction (PCR)-based molecular tests. Recombinase polymerase amplification (RPA) represents an isothermal version of the conventional PCR (cPCR) technique, being ideal for detecting Leishmania DNA, especially in field conditions.
A prospective and cross-sectional study was conducted to evaluate the diagnostic performance of RPA in the health centres of rural endemic sites or the evaluation centre (EC) of 11 Colombian municipalities and in a reference centre (RC).
Samples of 128 patients with suspected CL were included and processed for analysis by RPA vs DE in the EC and RPA vs DE and cPCR in the RC. The RPA performed at the EC was more sensitive (90.4% [95% confidence interval {CI} 81.9 to 95.7]) than the DE (42-67%) and the specificity was 72.7% (95% CI 57.2 to 85.0). Both the sensitivity and specificity increased to 100% when adjusting by the imperfect reference standard analysis method. In the RC, the sensitivity of RPA vs cPCR was 72% and the specificity was 69.8%, while the sensitivity of cPCR vs the DE test was 78.8% and the specificity was 81%.
The higher sensitivity and specificity shown by RPA in the EC, but also its ease and speed of use, justify performing RPA in the health centres of rural endemic sites. In addition, RPA eliminates the subjectivity inherent in the traditional DE.
皮肤利什曼病（CL）的诊断基于从病变处获得的样本中通过直接检查（DE）、培养或聚合酶链反应（PCR）为基础的分子检测来证明寄生虫的存在。重组酶聚合酶扩增（RPA）代表了传统 PCR（cPCR）技术的等温版本，非常适合检测利什曼原虫 DNA，尤其是在野外条件下。
进行了一项前瞻性和横断面研究，以评估 RPA 在农村流行地区的卫生中心或 11 个哥伦比亚市的评估中心（EC）以及参考中心（RC）的诊断性能。
纳入了 128 例疑似 CL 患者的样本，并在 EC 中通过 RPA 与 DE 进行分析，在 RC 中通过 RPA 与 DE 和 cPCR 进行分析。EC 中进行的 RPA 比 DE（42-67%）更敏感（90.4%[95%置信区间{CI}81.9 至 95.7]），特异性为 72.7%（95%CI 57.2 至 85.0）。当通过不完善的参考标准分析方法进行调整时，敏感性和特异性均提高到 100%。在 RC 中，RPA 与 cPCR 的敏感性为 72%，特异性为 69.8%，而 cPCR 与 DE 检测的敏感性为 78.8%，特异性为 81%。
RPA 在 EC 中表现出更高的敏感性和特异性，以及其易于使用和快速性，证明在农村流行地区的卫生中心进行 RPA 是合理的。此外，RPA 消除了传统 DE 固有的主观性。
