Effects of HIV infection on the serologic manifestations and response to treatment of syphilis in intravenous drug users.

OBJECTIVE

To describe the effects of human immunodeficiency virus (HIV) infection on the serologic manifestations and response to treatment of syphilis in intravenous drug users.

DESIGN

Cohort study of intravenous drug users.

SETTING

Medical clinic in a hospital-based methadone maintenance treatment program in New York City.

PATIENTS: Fifty patients with syphilis, of whom 31 were HIV seropositive and 19 HIV seronegative.

MEASUREMENTS: Serologic tests for syphilis and clinical manifestations.

RESULTS

Stage of syphilis at presentation was not associated with HIV serologic status. No unusual or fulminant manifestations of early syphilis or neurosyphilis were noted among HIV-seropositive cases. Maximum nontreponemal titers were higher among HIV-seropositive (median, 1:128) than among HIV-seronegative (median, 1:32) patients with syphilis (P = 0.05); this difference was present only among patients with first-episode syphilis. All 26 evaluable, HIV-seropositive patients treated for syphilis responded appropriately, including 13 patients given standard or less-than-standard doses of penicillin. Seven of 43 patients (16%) showed reversion to negative treponemal antibody assay results after treatment for syphilis; this finding was not associated with HIV infection, CD4 count, or stage of syphilis. Low nontreponemal titer was weakly associated with treponemal test reversion.

CONCLUSIONS

Infection with HIV did not alter the stage at presentation, clinical course, serologic manifestations, or response to treatment of syphilis in this cohort of intravenous drug users.