RESUMEN
BACKGROUND: Current syphilis tests cannot distinguish between active and past syphilis among patients with serofast rapid plasma reagin (RPR) titers. We investigated whether cytokine profiles might provide insight in the differentiation of active and treated syphilis. METHODS: We collected quarterly serum samples from participants at risk for incident syphilis in a prospective cohort study of men and male-to-female transgender women. We defined incident syphilis as a new RPR titer ≥ 1:8 or a fourfold increase from a prior RPR titer and a positive Treponema pallidum particle agglutination assay. We measured cytokine expression using a 63-multiplex bead-based Luminex assay (eBiosciences/Affymetrix, San Diego, California, USA). We used tertile bins and Chi square tests to identify differences in proportions of cytokines between samples from patients with active and treated syphilis. We constructed a network of cytokine profiles from those findings. We used R software (R version 3.4.1, R, Vienna, Austria) to fit models. RESULTS: We identified 20 pairs of cytokines (out of 1953 possible pairs) that differed between active and treated syphilis. From those, we identified three cytokine networks of interest: an Eotaxin-Rantes-Leptin network, a Mig-IL1ra-Trail-CD40L network, and an IL12p40-IL12p70 network. CONCLUSIONS: Differences in cytokine profiles are present among men and male-to-female transgender women with active and treated syphilis. Cytokine assays may be a potentially useful tool for identifying active syphilis among patients with serologic syphilis reactivity.
Asunto(s)
Citocinas/sangre , Sífilis/sangre , Treponema pallidum , Adulto , Estudios de Cohortes , Femenino , Humanos , Incidencia , Masculino , Sífilis/epidemiología , Personas Transgénero/estadística & datos numéricos , Treponema pallidum/inmunología , Adulto JovenRESUMEN
HIV infections in Peru are concentrated among men who have sex with men (MSM) and transgender women (TW). HIV testing rates among them remain low, delaying entrance into care. We assessed the prevalence of frequent HIV testing (at least every 6 months) and associated factors among 310 MSM and TW who attend sexual health clinics in Lima, Peru, and who reported that they were HIV seronegative or unaware of their status. Only 39% of participants tested frequently, and 22% had never tested; 29% reported that they were at low or no risk for acquiring HIV. Reporting low or no risk for acquiring HIV was associated with frequent testing (adjusted prevalence ratio [aPR] = 1.53, 95% CI 1.13-2.08); those reporting unprotected anal sex were less likely to test frequently (aPR = 0.66, 95% CI 0.50-0.87). HIV prevalence was 12% and did not vary by risk perception categories. This at-risk population tests infrequently and may not understand the risk of having unprotected sex.
Asunto(s)
Infecciones por VIH/diagnóstico , Homosexualidad Masculina/psicología , Tamizaje Masivo/estadística & datos numéricos , Aceptación de la Atención de Salud/estadística & datos numéricos , Personas Transgénero/psicología , Sexo Inseguro/estadística & datos numéricos , Adulto , Femenino , Infecciones por VIH/transmisión , Investigación sobre Servicios de Salud , Homosexualidad Masculina/estadística & datos numéricos , Humanos , Masculino , Evaluación de Necesidades , Perú/epidemiología , Prevalencia , Factores de Riesgo , Personas Transgénero/estadística & datos numéricos , Adulto JovenRESUMEN
Combining the detection of syphilis and HIV antibodies into one point-of-care test integrates syphilis screening into already existing HIV screening programs, which may be particularly beneficial in settings such as antenatal care. Using the INSTI Multiplex downward-flow immunoassay, we tested 200 stored serum samples from high-risk patients enrolled in a longitudinal study on HIV infection and syphilis in Peruvian men who have sex with men and transgender women. This rapid assay detected HIV and Treponema pallidum serum antibodies with sensitivities of 100% (95% confidence interval [CI], 95.9% to 100%) and 87.4% (95% CI, 81.4% to 92.0%), respectively, and specificities of 95.5% (95% CI, 89.9% to 98.5%) and 97.0% (95% CI, 84.2% to 99.9%), respectively (n = 200). The sensitivity for syphilis antibody detection was higher in patients with a rapid plasma reagin titer of ≥1:8 (97.3%) than in those with a titer of ≤1:4 (90%) or a nonreactive titer (66.7%).
Asunto(s)
Anticuerpos Antibacterianos/sangre , Técnicas de Laboratorio Clínico/métodos , Anticuerpos Anti-VIH/sangre , Infecciones por VIH/diagnóstico , Inmunoensayo/métodos , Sistemas de Atención de Punto , Sífilis/diagnóstico , Femenino , VIH/inmunología , Humanos , Estudios Longitudinales , Masculino , Perú , Sensibilidad y Especificidad , Personas Transgénero , Treponema pallidum/inmunologíaRESUMEN
We assessed the laboratory performance of the Chembio dual-path platform HIV-syphilis rapid immunodiagnostic test and electronic reader for detection of HIV and Treponema pallidum antibodies in 450 previously characterized serum specimens. For visual or electronic reader HIV antibody detection, the sensitivity was 100% and the specificity was 98.7%. For visual T. pallidum antibody detection, the test sensitivity was 94.7% and the specificity was 100.0%; with the electronic reader, the sensitivity was 94.7% and the specificity was 99.7%.