The performance of commonly used assays for diagnosis of syphilis varies considerably depending on stage of infection and sample type. In response to the need for improved syphilis diagnostics, we develop assays that pair PCR pre-amplification of the tpp47 gene of Treponema pallidum subsp. pallidum with CRISPR-LwCas13a. The PCR-LwCas13a assay achieves an order of magnitude better analytical sensitivity than real-time PCR with equivalent specificity. When applied to a panel of 216 biological specimens, including 135 clinically confirmed primary and secondary syphilis samples, the PCR-LwCas13a assay demonstrates 93.3% clinical sensitivity and 100% specificity, outperforming tpp47 real-time PCR and rabbit-infectivity testing. We further adapt this approach to distinguish Treponema pallidum subsp. pallidum lineages and identify genetic markers of macrolide resistance. Our study demonstrates the potential of CRISPR-based approaches to improve diagnosis and epidemiological surveillance of syphilis.

常用的梅毒诊断检测方法的性能因感染阶段和样本类型的不同而有很大差异。为了满足改进梅毒诊断的需求，我们开发了将梅毒螺旋体亚种tpp47基因的 PCR 预扩增配对的检测方法。苍白球与 CRISPR-LwCas13a。 PCR-LwCas13a 检测的分析灵敏度比具有同等特异性的实时 PCR 高一个数量级。当应用于 216 个生物样本（包括 135 个临床确认的一期和二期梅毒样本）时，PCR-LwCas13a 检测显示出 93.3% 的临床敏感性和 100% 的特异性，优于tpp47实时 PCR 和兔子感染性测试。我们进一步采用这种方法来区分梅毒螺旋体亚种。苍白球谱系并鉴定大环内酯类抗性的遗传标记。我们的研究证明了基于 CRISPR 的方法在改善梅毒诊断和流行病学监测方面的潜力。