Metaanalysis of the Performance of a Combined Treponemal and Nontreponemal Rapid Diagnostic Test for Syphilis and Yaws.

BACKGROUND: The human treponematoses are important causes of disease. Mother-to-child transmission of syphilis remains a major cause of stillbirth and neonatal death. There are also almost 100 000 cases of endemic treponemal disease reported annually, predominantly yaws. Rapid diagnostic tests (RDTs) would improve access to screening for these diseases. Most RDTs cannot distinguish current and previous infection. The Dual Path Platform (DPP) Syphilis Screen & Confirm test includes both a treponemal (T1) and nontreponemal (T2) component and may improve the accuracy of diagnosis. METHODS: We conducted a metaanalysis of published and unpublished evaluations of the DPP-RDT for the diagnosis of syphilis and yaws. We calculated the sensitivity, specificity, and overall agreement of the test compared with reference laboratory tests. RESULTS: Nine evaluations, including 7267 tests, were included. Sensitivity was higher in patients with higher titer rapid plasma reagin (≥1:16) for both the T1 (98.2% vs 90.1%, P < .0001) and the T2 component (98.2% vs 80.6%, P < .0001). Overall agreement between the DPP test and reference serology was 85.2% (84.4%-86.1%). Agreement was highest for high-titer active infection and lowest for past infection. CONCLUSIONS: The RDT has good sensitivity and specificity of the treponemal and nontreponemal components both in cases of suspected syphilis and yaws, although the sensitivity is decreased at lower antibody titers.

Evaluation of an immunochromatographic point-of-care test for the simultaneous detection of nontreponemal and treponemal antibodies in patients with syphilis.

We described the evaluation of the Syphilis Screening & Confirm Assay for the simultaneous detection of nontreponemal and treponemal antibodies. A total of 248 samples were evaluated. The sensitivity of the tests was 98.8%, 99.5% and 98.9%, while specificity was 94.7%, 88.9% and 93.2%, respectively, as compared with the rapid plasma reagin, Treponema pallidum hemagglutination assay, and fluorescent treponemal antibody absorption tests.

Nontreponemal tests in the diagnosis of neurosyphilis: an evaluation of the Venereal Disease Research Laboratory (VDRL) and the Rapid Plasma Reagin (RPR) tests.

The Venereal Disease Research Laboratory (VDRL) test has long been considered the best serological test for the diagnosis of neurosyphilis. The goal of this study was to find out if the Rapid Plasma Reagin (RPR) could be an alternative to the VDRL. Cerebrospinal fluid (CSF) and sera samples from patients in the following stages of syphilis were tested: 8 had symptomatic and 16 asymptomatic neurosyphilis, 4 were in the primary stage, 6 had secondary syphilis, and 92 were in the latent stage. We have also studied 61 samples from individuals with treated syphilis and 126 with other neurological diseases than neurosyphilis. All the CSF samples were studied with both RPR and VDRL tests. RPR and VDRL test results were mostly concordant. The specificity of these tests for current neurosyphilis was 99% for the VDRL and 99.3% for the RPR, whereas the sensitivity was 70.8 and 75%, respectively, for the VDRL and RPR. In view of these results it seems to us that the RPR could be an alternative to the VDRL in the diagnosis of neurosyphilis.