{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,7]],"date-time":"2026-04-07T20:17:27Z","timestamp":1775593047702,"version":"3.50.1"},"reference-count":29,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2021,4,23]],"date-time":"2021-04-23T00:00:00Z","timestamp":1619136000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:p>Rising rates of syphilis (<jats:italic>T. pallidum; Tp<\/jats:italic>) requires rapid diagnosis and treatment to manage the growing epidemic. Syphilis serology is imperfect and requires interpretation of multiple tests while molecular diagnostics allows for potential yes-no identification of highly infective, primary anogenital lesions. Accuracy of this testing modality has thus far been limited to small, highly selective studies. Therefore, we retrospectively assessed a large, adult population of patients with anogenital lesions seen at Sexually Transmitted Infection (STI) clinics in Alberta, Canada who were screened for syphilis and herpes simplex (HSV) 1\/2 using PCR to evaluate <jats:italic>Tp-<\/jats:italic>PCR versus serology to diagnose primary syphilis. 114 (3.1%) of the 3,600 adult patients had at least one <jats:italic>Tp<\/jats:italic>-PCR+ anogenital lesion with 99 (2.8%) patients having newly positive syphilis serology (new INNO-LIA positive or 4-fold RPR increase). <jats:italic>Tp-<\/jats:italic>PCR had a sensitivity of 49.3% (95% CI 42.6-56.1) and specificity of 99.9% (99.7-100.0). Positive predictive values and negative predictive values in the study population or when corrected for provincial prevalence were 97.4% (92.5-99.5) or 0.4% (0.4-1.2) and 96.7% (96.1-97.3) or 100.0% (100.0-100.0), respectively. Positive and negative likelihood ratios were estimated at 555 (178-1733) and 0.5 (0.4-0.6), respectively. Review of all <jats:italic>Tp<\/jats:italic>-PCR performed with or without exclusion of HSV-positive lesions resulted in no significant change in <jats:italic>Tp-<\/jats:italic>PCR characteristics. Interestingly, 12 of the <jats:italic>Tp-<\/jats:italic>PCR+ samples had negative serology at time of lesion sampling but became positive within our 28-day testing window. Overall, this study further supports the use of <jats:italic>Tp-<\/jats:italic>PCR as an accurate assay to rapidly identify, treat, and prevent the spread of primary syphilis.<\/jats:p>","DOI":"10.3389\/fcimb.2021.579660","type":"journal-article","created":{"date-parts":[[2021,4,23]],"date-time":"2021-04-23T09:02:43Z","timestamp":1619168563000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":9,"title":["Comparative Analysis of Molecular and Serologic Testing for Primary Syphilis: A Population-Based Cohort Study"],"prefix":"10.3389","volume":"11","author":[{"given":"Caley Bryce","family":"Shukalek","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bonita","family":"Lee","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sumana","family":"Fathima","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Angel","family":"Chu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kevin","family":"Fonseca","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ranjani","family":"Somayaji","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2021,4,23]]},"reference":[{"key":"B1","article-title":"Canada PHAo","volume-title":"Infectious syphilis cases reported in Canada 2009\u20132018","year":"2019"},{"key":"B2","volume-title":"Interactive Health Data Application","year":"2019"},{"key":"B3","volume-title":"Notifiable Disease Charts","year":"2020"},{"key":"B4","doi-asserted-by":"publisher","first-page":"1086","DOI":"10.1086\/514751","article-title":"Genital ulcers: etiology, clinical diagnosis, and associated human immunodeficiency virus infection in Kingston, Jamaica","volume":"28","author":"Behets","year":"1999","journal-title":"Clin. 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