Qquellon Jazmin, Vargas Silver K, Vasquez Francesca, Reyes-Diaz E Michael, Konda Kelika A, Caceres Carlos F, Klausner Jeffrey D
Centro de Investigación Interdisciplinaria en Sexualidad, SIDA y Sociedad, Universidad Peruana Cayetano Heredia, Lima, Peru.
Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
Microbiol Spectr. 2025 Jan 7;13(1):e0129824. doi: 10.1128/spectrum.01298-24. Epub 2024 Dec 10.
Serological tests for syphilis require equipment unavailable in many health centers; however, point-of-care testing facilitates rapid screening using finger-prick whole blood samples. A further improvement could be oral fluid for ease of use. We evaluated the performance of treponemal antibody point-of-care testing for syphilis screening using oral fluid samples. We recruited users of STI clinics in Lima, Peru. We collected oral fluid using the OraSure collection device (OraSure Technologies Inc., USA) according to the manufacturer's instructions and serum from each participant. Oral fluid and serum were analyzed using the SD Bioline Syphilis 3.0 rapid test (Standard Diagnostics Inc., Korea). Serum was also tested using RPR (RPR slide test, Wiener Laboratorios SAIC, Argentina) and TPPA (Serodia, Fujirebio Diagnostics Inc., Japan). We assessed oral fluid rapid test overall percent agreement, sensitivity, specificity, and Kappa coefficient against serum SD Bioline Syphilis, TPPA, and RPR. Among 323 participants, nearly half (51.3%) reported prior syphilis. The overall percent agreement, sensitivity, specificity, and Kappa coefficient of oral fluid were 71.0% (95% CI: 65.6%-75.8%), 78.1% (71.1%-83.7%), 63.5% (55.8%-70.6%), and 0.42% (0.32%-0.52%), respectively, versus serum SD Bioline Syphilis. A similar performance was obtained versus serum TPPA. When limiting the sample to TPPA-reactive with RPR titer ≥1:8, the sensitivity increased to 88.1% (75.0%-94.8%), whereas the specificity did not vary (65.3% [57.2%-72.6%]). We observed a good performance of the rapid treponemal test using oral fluid. Further investigations are needed to improve the specificity of oral fluid as a potential sample for accurate syphilis screening.IMPORTANCEPoint-of-care tests are essential for rapid and efficient screening of syphilis, especially in low-resource settings. Oral fluid specimens offer a noninvasive, accessible, and practical alternative to traditional blood samples. Our study evaluated the performance of a rapid treponemal test using oral fluid specimens. We found that the rapid treponemal test using oral fluid had good sensitivity compared with the rapid treponemal test using serum and the non-treponemal RPR test. This suggests that oral fluid could be a viable option for syphilis screening, facilitating broader and faster access to diagnosis and treatment. However, further studies are needed to improve the specificity of this method to ensure accurate screening in diverse clinical scenarios.
梅毒血清学检测需要许多健康中心都没有的设备；然而，即时检测便于使用手指刺破采集的全血样本进行快速筛查。进一步的改进可以是使用口腔液，因其使用方便。我们评估了使用口腔液样本进行梅毒筛查的密螺旋体抗体即时检测的性能。我们招募了秘鲁利马性传播感染诊所的患者。我们按照制造商的说明，使用OraSure采集装置（美国OraSure Technologies公司）采集每位参与者的口腔液和血清。使用SD Bioline梅毒3.0快速检测（韩国标准诊断公司）对口腔液和血清进行分析。血清还使用RPR（RPR玻片试验，阿根廷维纳实验室股份公司）和TPPA（日本富士瑞必欧诊断公司的Serodia）进行检测。我们评估了口腔液快速检测与血清SD Bioline梅毒检测、TPPA检测和RPR检测相比的总体一致性百分比、敏感性、特异性和Kappa系数。在323名参与者中，近一半（51.3%）报告曾患梅毒。与血清SD Bioline梅毒检测相比，口腔液的总体一致性百分比、敏感性、特异性和Kappa系数分别为71.0%（95%CI：65.6%-75.8%）、78.1%（71.1%-83.7%）、63.5%（55.8%-70.6%）和0.42%（0.32%-0.52%）。与血清TPPA检测相比也获得了类似的结果。当将样本限制为TPPA反应性且RPR滴度≥1:8时，敏感性提高到88.1%（75.0%-94.8%），而特异性没有变化（65.3%[57.2%-72.6%]）。我们观察到使用口腔液进行快速密螺旋体检测的性能良好。需要进一步研究以提高口腔液作为梅毒准确筛查潜在样本的特异性。重要性即时检测对于梅毒的快速有效筛查至关重要，尤其是在资源匮乏的环境中。口腔液标本为传统血液样本提供了一种非侵入性、易获取且实用的替代方案。我们的研究评估了使用口腔液标本进行快速密螺旋体检测的性能。我们发现，与使用血清进行的快速密螺旋体检测和非密螺旋体RPR检测相比，使用口腔液进行的快速密螺旋体检测具有良好的敏感性。这表明口腔液可能是梅毒筛查的一个可行选择，有助于更广泛、更快地获得诊断和治疗。然而，需要进一步研究以提高该方法的特异性，以确保在不同临床场景中进行准确筛查。
