Abstract：
OBJECTIVE: We evaluated the field diagnostic accuracy of a syphilis rapid test (RDT), using serum and whole blood by non-laboratorians in two Canadian Arctic communities.
METHODS: We implemented a multisite prospective field evaluation wherein patients were screened by an RDT containing treponemal and non-treponemal components (Chembio DPP® Syphilis Screen & Confirm) between January 2020 and December 2021. Venous whole blood and serum were collected for rapid testing and compared with laboratory-based serology reference testing using a reverse sequence algorithm of treponemal and rapid plasma reagin (RPR) testing.
RESULTS: Overall, 135 whole blood and 139 serum specimens were collected from 161 participants during clinical encounters. Treponemal-RDT sensitivity against a treponemal-reference standard (38/161 confirmed cases) was similar for serum (78% [95% CI: 61-90%]) and whole blood (81% [95% CI: 63-93%]). In those with RPR titres ≥1:8 (i.e. suggestive of recent/active infection), sensitivity increased to 93% (95% CI: 77-99%) for serum and 92% (95% CI: 73-99%) for whole blood. Treponemal-RDT specificity was excellent (99% [95% CI: 95-100%]) for both specimen types. Non-treponemal-RDT sensitivity against RPR was 94% (95% CI: 80-99%) for serum and 79% (95% CI: 60-92%) for whole blood. Sensitivity increased to 100% (95% CI: 88-100%) for serum and 92% (95% CI: 73-99%) for whole blood when RPR titres ≥1:8. RDT performance with whole blood was similar to that with serum.
CONCLUSIONS: Non-laboratorians using the RDT accurately identified individuals with infectious syphilis under real-world conditions in an intended-use setting at the point of care. Implementing the RDT can eliminate treatment delays and may enhance disease control.
METHODS: We implemented a multisite prospective field evaluation wherein patients were screened by an RDT containing treponemal and non-treponemal components (Chembio DPP® Syphilis Screen & Confirm) between January 2020 and December 2021. Venous whole blood and serum were collected for rapid testing and compared with laboratory-based serology reference testing using a reverse sequence algorithm of treponemal and rapid plasma reagin (RPR) testing.
RESULTS: Overall, 135 whole blood and 139 serum specimens were collected from 161 participants during clinical encounters. Treponemal-RDT sensitivity against a treponemal-reference standard (38/161 confirmed cases) was similar for serum (78% [95% CI: 61-90%]) and whole blood (81% [95% CI: 63-93%]). In those with RPR titres ≥1:8 (i.e. suggestive of recent/active infection), sensitivity increased to 93% (95% CI: 77-99%) for serum and 92% (95% CI: 73-99%) for whole blood. Treponemal-RDT specificity was excellent (99% [95% CI: 95-100%]) for both specimen types. Non-treponemal-RDT sensitivity against RPR was 94% (95% CI: 80-99%) for serum and 79% (95% CI: 60-92%) for whole blood. Sensitivity increased to 100% (95% CI: 88-100%) for serum and 92% (95% CI: 73-99%) for whole blood when RPR titres ≥1:8. RDT performance with whole blood was similar to that with serum.
CONCLUSIONS: Non-laboratorians using the RDT accurately identified individuals with infectious syphilis under real-world conditions in an intended-use setting at the point of care. Implementing the RDT can eliminate treatment delays and may enhance disease control.
摘要：
目的：我们评估了梅毒快速检测（RDT）的现场诊断准确性，加拿大两个北极社区的非实验室人员使用血清和全血。
方法：我们在2020年1月至2021年12月之间实施了一项多站点前瞻性现场评估，其中患者通过含有螺旋体和非螺旋体成分的RDT（ChembioDPP®梅毒筛查和确认）进行筛查。收集静脉全血和血清进行快速测试，并使用螺旋体和快速血浆反应素（RPR）测试的反向序列算法与基于实验室的血清学参考测试进行比较。
结果：总体而言，在临床接触期间，从161名参与者收集了135份全血和139份血清样本。血清(78%[95%CI:61-90%])和全血(81%[95%CI:63-93%])对密螺旋体参考标准(38/161例确诊病例)的密螺旋体RDT敏感性相似。在RPR滴度≥1:8（即提示近期/活动性感染）的患者中，血清敏感性增加至93%(95%CI:77-99%),全血敏感性增加至92%(95%CI:73-99%).两种标本类型的密螺旋体RDT特异性均出色（99％[95％CI：95-100％]）。血清对RPR的非螺旋体RDT敏感性为94％（95％CI：80-99％），全血对RPR的敏感性为79％（95％CI：60-92％）。当RPR滴度≥1：8时，血清的敏感性增加到100％（95％CI：88-100％），全血的敏感性增加到92％（95％CI：73-99％）。全血的RDT性能与血清相似。
结论：使用RDT的非实验室人员在现实世界条件下，在预期使用环境下，在护理点准确识别出传染性梅毒个体。实施RDT可以消除治疗延迟，并可以加强疾病控制。
方法：我们在2020年1月至2021年12月之间实施了一项多站点前瞻性现场评估，其中患者通过含有螺旋体和非螺旋体成分的RDT（ChembioDPP®梅毒筛查和确认）进行筛查。收集静脉全血和血清进行快速测试，并使用螺旋体和快速血浆反应素（RPR）测试的反向序列算法与基于实验室的血清学参考测试进行比较。
结果：总体而言，在临床接触期间，从161名参与者收集了135份全血和139份血清样本。血清(78%[95%CI:61-90%])和全血(81%[95%CI:63-93%])对密螺旋体参考标准(38/161例确诊病例)的密螺旋体RDT敏感性相似。在RPR滴度≥1:8（即提示近期/活动性感染）的患者中，血清敏感性增加至93%(95%CI:77-99%),全血敏感性增加至92%(95%CI:73-99%).两种标本类型的密螺旋体RDT特异性均出色（99％[95％CI：95-100％]）。血清对RPR的非螺旋体RDT敏感性为94％（95％CI：80-99％），全血对RPR的敏感性为79％（95％CI：60-92％）。当RPR滴度≥1：8时，血清的敏感性增加到100％（95％CI：88-100％），全血的敏感性增加到92％（95％CI：73-99％）。全血的RDT性能与血清相似。
结论：使用RDT的非实验室人员在现实世界条件下，在预期使用环境下，在护理点准确识别出传染性梅毒个体。实施RDT可以消除治疗延迟，并可以加强疾病控制。
