Evaluation of the usefulness of routine molecular biology for the diagnosis of primary syphilis by assessing the serological status of patients with PCR‐confirmed syphilitic ulcers

Abstract

Evaluation of the usefulness of routine molecular biology for the diagnosis of primary syphilis by assessing the serological status of patients with PCR-confirmed syphilitic ulcers Dear Editor, Syphilis, causes by Treponema pallidum (TP), has its maximum contagiousness in early phases where TP DNA may be detectable by genomic amplification. The diagnosis of primary syphilis is currently based on anamnestic data, clinical examination and indirect serological tests: a specific treponemal test (TT) and a nontreponemal test (NTT). However, the clinical presentation of syphilitic chancre may be not specific 1 compared to other causes of buccal or anogenital ulcers and serological tests may lack sensitivity. It is therefore important to consider early detection of primary syphilis by genomic amplification from lesion exudate, to ensure that patients receive appropriate treatment, and thus reduce transmission. The aim of this study was to assess the relevance of the PCR assay in primary syphilis patients in comparison with their serological status. All clinical swabs were obtained from patients with a suspected early syphilis between September 2010 and August 2021 at eight STI centres in France. Clinical data were documented (age, sex, sexual orientation, HIV status, clinical signs, serology status) as part of the GENOSYPH study (CPP S.C. 3005, CNIL No. 1208504). Clinical swabs exudates were tested by real-time quantitative PCR (qPCR) as