In order to assess the trend of new cases of HIV infection, spontaneous requests of HIV counseling and testing made at our outpatient Center since 1993 were retrospectively evaluated. During the considered 6-year period, 7,492 subjects had voluntary HIV testing, and 225 proved HIV-positive (3.0%). While the overall number of spontaneous requests of HIV serology did not show remarkable variations over time, a tendency towards a significant increase of newly diagnosed HIV disease was observed during the past two years (1997 and 1998). In particular, among the 57 subjects with HIV infection disclosed in 1998, a predominance of young adults and a relatively elevated frequency of females compared with males was demonstrated, while heterosexual (38 cases) and homo-bisexual contacts (18 cases) accounted for the great majority of newly identified retroviral infections, and 66.1% out of the 56 patients who acquired HIV infection by sexual route were stable partners of individuals with known HIV disease. Although epidemiological estimates foresaw a progressive reduction of cases of HIV infection since 1990, a surprising increase of newly diagnosed HIV disease among patients who spontaneously asked for HIV testing was observed in our experience. The apparent temporal coincidence of this phenomenon with the remarkable advances obtained in both diagnostic and therapeutic strategies of HIV disease just since 1996, could not be a fortuitous event. The non-decline of newly diagnosed cases of HIV infection should re-orient strategies of communication and prophylaxis dealing with HIV disease, and involving the general population and people with persisting high-risk behavior.