Clinical characteristics and prognostic value of acute retroviral syndrome among injecting drug users

Abstract

To estimate the frequency of acute retroviral syndrome associated with HIV infection among injecting drug users (IDU), and to determine the extent to which acute retroviral syndrome predicts a faster rate of progression to AIDS and immunosuppression in this population. Prospective study of HIV seroconverters (median follow-up, 50.5 months). Sixteen clinical centres throughout Italy established to study the natural history of HIV infection. Three hundred and ninety-one IDU for whom the date of HIV seroconversion was established with a 9-month precision. Incidence of acute retroviral syndrome with signs and symptoms that included fever (temperature >38°C) occurring within 6 months prior to the time of first positive HIV test, progression to AIDS, crude and adjusted relative hazard of AIDS using survival analysis techniques, and trajectories of CD4+ cell counts using a piece-wise linear regression model incorporating the degree of dependency of within-person measurements. Of 391 HIV seroconverters, 39 (10.0%) were diagnosed with acute retroviral syndrome. During follow-up, 13 seroconverters with acute retroviral syndrome and 24 asymptomatic seroconverters developed AIDS. The Kaplan-Meier estimates for the cumulative AIDS incidence during 4.5 years of follow-up were 26.8 and 6.5%, respectively; the relative hazard of developing AIDS for acute retroviral syndrome was 5.59 (95% confidence interval, 2.79–11.20) after adjustment for age, sex and year of seroconversion. Although CD4+ level within the first year from seroconversion was similar, the rate of CD4+ cell decline after 1 year from seroconversion was faster in individuals with acute retroviral syndrome than in those without this syndrome (P Conclusions Among HIV-infected IDU, a distinct acute retroviral syndrome is apparent and associated with a faster rate of clinical progression to AIDS and HIV-related immunosuppression.