BACKGROUND To meet the WHO target of eradicating yaws by 2030, highly sensitive and specific diagnostic tools are needed. A multiplex Treponema pallidum-Haemophilus ducreyi loop-mediated isothermal amplification (TPHD-LAMP) test holds promise as a near-patient diagnostic tool for yaws and H ducreyi. We conducted a prospective evaluation in Cameroon, Côte d'Ivoire, Ghana, and the Republic of the Congo to determine the diagnostic accuracy of the TPHD-LAMP test, as well as to assess its acceptability, feasibility, and cost. METHODS Active case searching within schools and communities was used to locate participants with clinically suspicious laws-like lesions. Individuals with serologically confirmed active yaws provided paired lesion swabs between March, 2021, and April, 2023. For each participant, one swab was tested with the TPHD-LAMP at a local district laboratory and the other with reference quantitative PCR (qPCR) tests conducted at national reference laboratories. The primary outcome was TPHD-LAMP test sensitivity and specificity compared with qPCR. Laboratory technicians were interviewed using a multiple-choice survey to gauge acceptability and feasibility of the TPHD-LAMP test. Costs of each test were calculated. FINDINGS Of 3085 individuals with at least one suspected yaws lesion, 531 (17%) were serologically confirmed. We enrolled 493 participants with seropositive yaws and a further 32 with negative serology. The sensitivity of the TPHD-LAMP test for detecting T pallidum was 63% (95% CI 56-70) and the specificity was 66% (95% CI 61-71). Sensitivity and specificity for T pallidum improved to 73% (63-82; p=0·0065) and 75% (68-80; p=0·0003), respectively, in H ducreyi-negative samples. Interviews highlighted challenges in user-friendliness and practicality of the TPHD-LAMP test. The cost of the test per sample was one third of that of qPCR, although the TPHD-LAMP test entailed higher costs to establish the assay. INTERPRETATION This was the first multi-country diagnostic evaluation of a molecular test for yaws. The TPHD-LAMP testing, in its current form, falls short of the WHO target product profile criteria for yaws diagnostics. These findings highlight the importance of assessing new diagnostics in real-world conditions to ensure their suitability for programmatic use. FUNDING The EDCTP2 programme supported by the EU.

中文翻译：

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雅司病的环形介导等温扩增试验：多国诊断准确性评估。


背景 为了实现 WHO 到 2030 年根除雅司病的目标，需要高度敏感和特异性的诊断工具。多重梅毒螺旋体-杜克雷嗜血杆菌环介导的等温扩增 （TPHD-LAMP） 检测有望作为雅司病和杜克雷嗜血杆菌的近患者诊断工具。我们在喀麦隆、科特迪瓦、加纳和刚果共和国进行了前瞻性评估，以确定 TPHD-LAMP 检测的诊断准确性，并评估其可接受性、可行性和成本。方法 在学校和社区内主动进行病例搜索，以定位具有临床可疑 law 样病变的参与者。血清学证实的活动性雅司病个体在 2021 年 3 月至 2023 年 4 月期间提供了成对的病变拭子。对于每个参与者，一个拭子在当地地区实验室使用 TPHD-LAMP 进行测试，另一个在国家参考实验室进行参考定量 PCR （qPCR） 测试。与 qPCR 相比，主要结局是 TPHD-LAMP 检测的敏感性和特异性。使用多项选择调查对实验室技术人员进行访谈，以衡量 TPHD-LAMP 测试的可接受性和可行性。计算每次测试的费用。结果在 3085 名至少有 1 例疑似 Yaws 病变的个体中，531 例 （17%） 经血清学证实。我们招募了 493 名血清阳性 yaw 参与者和另外 32 名血清学阴性参与者。TPHD-LAMP 检测梅毒螺旋体的敏感性为 63% （95% CI 56-70），特异性为 66% （95% CI 61-71）。在 H ducreyi 阴性样本中，梅毒螺旋体的敏感性和特异性分别提高到 73% （63-82;p=0·0065） 和 75% （68-80;p=0·0003）。 访谈强调了 TPHD-LAMP 测试在用户友好性和实用性方面的挑战。每个样本的检测成本是 qPCR 的三分之一，尽管 TPHD-LAMP 检测需要更高的成本来建立检测。解释 这是首次对雅司病分子检测进行多国诊断评估。目前形式的 TPHD-LAMP 检测不符合 WHO 针对雅司病诊断的目标产品概况标准。这些发现强调了在现实条件下评估新诊断以确保其适合编程使用的重要性。资金 由欧盟支持的 EDCTP2 计划。