CLINICAL CHARACTERISTICS AND PROGNOSTIC VALUE OF ACUTE RETROVIRAL SYNDROME AMONG INJECTING DRUG-USERS

Objective: To estimate the frequency of acute retroviral syndrome asso ciated with HIV infection among injecting drug users (IDU), and to det ermine the extent to which acute retroviral syndrome predicts a faster rate of progression to AIDS and immunosuppression in this population. Design: Prospective study of HIV seroconverters (median follow-up, 50 .5 months). Setting: Sixteen clinical centres throughout Italy establi shed to study the natural history of HIV infection. Patients: Three hu ndred and ninety-one IDU for whom the date of HIV seroconversion was e stablished with a 9-month precision. Main outcome measures and methods : Incidence of acute retroviral syndrome with signs and symptoms that included fever (temperature >38 degrees C) occurring within 6 months p rior to the time of first positive HIV test, progression to AIDS, crud e and adjusted relative hazard of AIDS using survival analysis techniq ues, and trajectories of CD4+ cell counts using a piece-wise linear re gression model incorporating the degree of dependency of within-person measurements. Results: Of 391 HIV seroconverters, 39 (10.0%) were dia gnosed with acute retroviral syndrome. During follow-up, 13 seroconver ters with acute retroviral syndrome and 24 asymptomatic seroconverters developed AIDS. The Kaplan-Meier estimates for the cumulative AIDS in cidence 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 a ge, sex and year of seroconversion. Although CD4+ level within the fir st 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<0.001). Co nclusions: Among HIV-infected IDU, a distinct acute retroviral syndrom e is apparent and associated with a faster rate of clinical progressio n to AIDS and HIV-related immunosuppression.