Predictors of serological failure after treatment in HIV-infected patients with early syphilis in the emerging Era of universal antiretroviral therapy use

Abstract

BackgroundThe optimal treatment of early syphilis (primary, secondary and early latent) in HIV-infected patients remains controversial. The Center for Diseases Control STD Treatment Guidelines recommended 1 dose of benzathine penicillin G (BPG) regardless of HIV infection. However, many providers modify the treatment for early syphilis.MethodsWe performed a retrospective chart review of all cases of early syphilis with positive serologic test results in HIV-infected patients from May 2006 to May 2011 in 2 large, urban HIV clinics. Early syphilis includes primary, secondary, and early latent syphilis. Serological failure was defined as a lack of 4-fold decrease in rapid plasma reagent (RPR) titers 9 to 12 months after syphilis treatment. Patients whose RPR titers decreased after treatment and subsequently increased 4-fold at 9 to 12 months were excluded from the analysis of serological response because of possibility as “reinfection”. Baseline characteristics were tested as predictive factors of serological failure using a univariate and multivariate logistic regression model, respectively.ResultsOf 560 patients with confirmed cases of early syphilis, 51 (9.0%) experienced serological failure. Multivariate logistic regression modeling demonstrated that the predictive factors associated with serological failure after early syphilis treatment were baseline RPR titer ≤ 1:16 (OR 3.91 [95% CI, 2.04-7.47]), a previous history of syphilis (OR 3.12 [95% CI, 1.55-6.26]), and a CD4 T-cell count below 350 cells/ml (OR 2.41 [95% CI, 1.27-4.56]). Of note, type of syphilis treatment (1 dose versus 3 doses of BPG) did not appear to affect the proportion of serological failure (4% versus 10%, P = 0.29), however the power of this study to detect small differences was limited.ConclusionsHIV-infected patients with baseline RPR titer ≤1:16, syphilis history, and/or a CD4 T-cell count <350 cells/ml should be closely monitored for serologic failure after early syphilis treatment. This study did not detect a substantial difference between treatment with > 1 dose of BPG and decreased frequency of serological failure, supporting the current recommendation that one dose of BPG is adequate treatment for early syphilis in HIV-infected patients.

Incidence and Predictors of Serological Treatment Response in Early and Late Syphilis Among People Living With HIV

“…Treatment failure was observed in 12% of episodes that were included in the study, which is a proportion that is similar to what has been observed in other studies regarding uninfected individuals [11] and PLWH in the post-ART era [9, 10]. …”

“…Immunosuppression has been associated with treatment failure in syphilis, as reported in previous studies on PLWH [10, 22] and subjects with an impaired immune system have been reported to respond more slowly to syphilis treatment, compared with those with a good immunological status [10, 24]. In this study, higher RPR titers were associated with treatment response both in early and late syphilis.…”

“…Additionally, subjects with lower RPR titers may have a longer duration of infection, with lower metabolic activity of the microorganism and a delayed response to treatment [26]. Finally, a 4-fold decline in the RPR titer (the definition of treatment response) is more easily obtained in patients with higher titers at the time of diagnosis of syphilis [10]. …”

Factors associated with syphilis incidence in the HIV-infected in the era of highly active antiretrovirals

“…[22] In contrast, other studies suggest that ART has no influence on syphilis incidence, [23,24] or even increases it, [25–27] while others suggest no effect of ART on treatment or serological failure. [28,29] …”

Sexually transmitted coinfections. HIV coinfections

“…Más utánvizsgá-lók nem találtak kevesebb kezelési elégtelenséget, mintha nagyobb dózisban adták volna a penicillint, de felhívják a fi gyelmet, hogy ha az RPR kezdeti titere <1:16, és/vagy a CD4+ T-lymphocyta-szám <350 sejt/ μl, gondos monitorozás szükséges szerológiai rezisztencia irányában [46]. 2007 előtt syphilisszel kezelt HIVpozitív neurosyphilises betegek ellenőrző vizsgálata évekkel később mind a klinikai vizsgálat, mind a liquor cerebrospinalis vizsgálat tekintetében negatív volt (34/35 esetben) [47].…”