Sero-prevalence and comparative study of diagnostic tests in syphilis in tertiary care teaching hospital, Western India

Background: Syphilis testing may be a useful strategy to provide data for implementation of Sexually transmitted disease (STD) control programme. Serological surveys continue to be the best source of information on the prevalence of syphilis. Aims: The aim of study was to estimate the seroprevalence and to determine diagnostic performance of treponemal TPHA (Treponemapallidum hemagglutination assay) and nontreponemal RPR (Rapid plasma regain) test for syphilis. Materials and Methods: To assess the prevalence rate Total 13115 serum samples of patients with clinically suspected syphilis infection and antenatal screening were analyzed by using either RPR test or by TPHA in tertiary care hospital, western India during time periods of March 2014 to April 2015. To assess the reactivity of RPR test in comparison with TPHA test, serum samples from 148 patients with high clinical suspection of syphilis infection were investigated by both above mentioned methods. Results: Among tested 13115 serum samples of patients, overall seroprevalence was 0.930% (13115/122). Highest seroprevalence (6.21%) was seen in STD clinic attendees. Among 148 samples which were tested by both assays, 98 were truly reactive by TPHA while 92 were by RPR. Thus TPHA was found to be more sensitive and specific while comparing the results with RPR test. Conclusion: Serological surveys need to be continuously done to avoid the adverse consequences from missed diagnosis. TPHA should be performed along with RPR test as no single serological test can act as the marker of acute infection