The authors consider the clinical aspects of the natural history of HTLV-III/LAV infection. Then, they report on the clinical experience on AIDS and AIDS-related complex in the Veneto area. The most represented risk factor of the observed HTLV-III seropositive patients is intravenous drug abuse. 41 patients were asymptomatic, 91 patients had persistent generalized lymphoadenopathy with the presence or absence of constitutional symptoms (LAS/ARC), 9 patients were affected by "minor" opportunistic infections, 9 were affected by idiopathic thrombocytopenia and 7 were affected by full-blown AIDS. In this study the relationship between deterioration of cellular-mediated immunity and the clinical decline in HTLV III patients is confirmed by the decrease of circulating T4+ cells and of the T4+/T8+ ratio. High levels of seric IgG have been found in all patients, but only thrombocytopenic patients showed a statistically significant increased value.
