Syphilis in HIV‐infected patients: predictors for serological failure and serofast state

Abstract

PurposeHIV-infected patients treated for syphilis may be at increased risk for serological failure and serofast state. Our aim was to analyse serological response to treatment in HIV-infected patients diagnosed with syphilis, and factors associated with serological cure and serofast state.MethodsOpen-label, no controlled study of a series of HIV-patients diagnosed with syphilis during 2004–2011. Patients were categorized by rapid plasma reagin titer (RPR) into success (4-fold decrease in RPR by 12 or 24 months after treatment of early or late syphilis), serofast (success with persistently stable reactive RPR), and failure/re-infection (failure to decrease 4-fold in RPR by 12 or 24 months after treatment or sustained 4-fold increase in RPR after treatment response).Results141 HIV-patients were diagnosed with syphilis during the study period (104 early syphilis, 36 late or indeterminate latent syphilis). The mean age was 36.3 years, 98.5% were male, and 87.2% homosexual men. In 46 (32.6%) cases, HIV and syphilis infection diagnosis were coincident (mean CD4 457/mm3 and HIV-VL 4.72 log10). Among patients with prior known HIV infection, 65 were on antiretroviral therapy (ART) at syphilis diagnosis (mean CD4 469/mm3, 76.9% undetectable HIV-VL). 116 patients satisfied criteria for serological response analysis (89 early, 24 late/indeterminate). At 12 months of early syphilis treatment (89.2% penicillin) there were 16 (18%) failures, and at 24 months of late/indeterminate syphilis (91.7% penicillin) there were 5 (18.5%) failures. Overall, 36 (31.0%) patients presented serofast state. Treatment failure was related with lower CD4 count (295 vs 510/mL; p=0.045) only in patients with coincident diagnosis. Serofast state was related with older age (41 vs 36 years; p=0.024), and lower CD4 count (391 vs 513/mm3; p=0.026).ConclusionsIn this series of HIV-infected patients, with many patients on ART and with good immunological and virological parameters, serological failure and serofast state were frequent. Immunological status, and age could influence on serological response to syphilis treatment in HIV-infected patients.

Regulatory T Cells in Peripheral Blood and Cerebrospinal Fluid of Syphilis Patients with and without Neurological Involvement

“…The immune status of serofast patients is unclear. A recent study reported that HIV-infected patients are at increased risk for serofast state after treatment [54]. Our results showed that these patients had enhanced circulating Treg numbers and suppressive function, also suggesting serofast status may be associated with a systemic immune suppression.…”

Early syphilis treatment in HIV‐infected patients: single dose vs. three doses of benzathine penicillin G

“…Some studies suggest that immunological status can influence serological response to syphilis treatment in HIVinfected patients. 16,17 We could not confirm these findings as the number of CD4 cells was not a significant modifier of serological response to penicillin treatment. However, our sample was too small.…”

A double-edged sword: does highly active antiretroviral therapy contribute to syphilis incidence by impairing immunity toTreponema pallidum?

“… 9 Among 104 early syphilis and 36 late or indeterminate latent syphilis cases in a Malaga study from 2004 to 2011, 65 of 85 (76.4%) with prior known HIV-1 infection were taking HAART. 10 A retrospective, descriptive study at the University of Alabama found 40 incident syphilis cases from 2004 to 2007 in 1544 patients who were HIV-1 positive. 11 Two-thirds were receiving HAART when syphilis was diagnosed including all five patients with primary syphilis.…”