%0 Journal Article
%T Sensitivity and specificity of two investigational Point of care tests for Syphilis and HIV (PoSH Study) for the diagnosis and treatment of infectious syphilis in Canada: a cross-sectional study.
%A Singh AE
%A Ives N
%A Gratrix J
%A Vetland C
%A Ferron L
%A Crawford M
%A Hale-Balla L
%A Dong K
%A Meyer G
%A Smyczek P
%A Galli R
%A Rourke SB
%A Fonseca K
%A
%J Clin Microbiol Infect
%V 29
%N 7
%D Jul 2023 2
%M 36868357
%F 13.31
%R 10.1016/j.cmi.2023.02.015
%X OBJECTIVE: Single-visit testing and treatment for syphilis can reduce follow-up visits. The objectives of this study were to evaluate the performance and treatment outcomes of two dual syphilis/HIV point-of-care tests (POCTs).
METHODS: Participants aged 16 years and older were offered concurrent syphilis/HIV POCTs with fingerstick blood sampling using two extremely rapid (<5 minutes) devices (MedMira Multiplo Rapid TP/HIV test and INSTI Multiplex HIV-1/HIV-2/Syphilis Antibody Test). Those with positive POCT results were offered same-day syphilis treatment and linkage to HIV care. Nurses performed testing at two emergency departments, a First Nations community, a correctional facility, and a sexually transmitted infection clinic. POCT results were compared with those of standard serological testing. Sensitivity and specificity were calculated.
RESULTS: Between August 2020 and February 2022, 1526 visits were completed. Both POCTs accurately identified participants with HIV (sensitivity, 100% [24 of 24]; 95% CI, 86.2-100%; specificity, 99.6% [1319 of 1324]; 95% CI, 99.1-99.8%), linking 24 HIV cases to care. Both tests were most sensitive with a rapid plasma reagin (RPR) of ≥1:8 dilutions (Multiplo: sensitivity, 98.3% [231 of 235]; 95% CI, 95.7-99.3%; specificity, 99.5% [871 of 875]; 95% CI, 98.8-99.8%; INSTI Multiplex: sensitivity, 97.9% [230 of 235]; 95% CI, 95.1-99.1%; specificity, 99.8% [873 of 875]; 95% CI, 99.2-99.9%) and least sensitive with non-reactive RPR (Multiplo: sensitivity, 54.1% [59 of 109]; 95% CI, 44.8-63.2%; specificity, 99.5% [871 of 875]; 95% CI, 98.8-99.8%; INSTI Multiplex: sensitivity, 28.4% [31 of 109]; 95% CI, 20.8-37.5%; specificity, 99.8% [873 of 875]; 95% CI, 99.2-99.9%). Eighty-five percent of participants with infectious syphilis were treated on the same day as the positive POCT result.
CONCLUSIONS: Two extremely rapid (<5 minutes) dual syphilis/HIV POCTs showed excellent sensitivity and specificity for the diagnosis of active syphilis (RPR, ≥1:8 dilutions) and HIV and confirmed the ability to offer single-visit testing and treatment for syphilis and linkage to HIV care in diverse clinical settings.