Acquired immunodeficiency without HIV infection: epidemiology and clinical outcome in Italy. The Italian Study Group on non-HIV AIDS.

Abstract

Cases of acquired immunodeficiency without HIV infection, but with depletion of CD4 T lymphocytes have been reported since 1989. We estimated the prevalence of this condition in Italy and evaluated its clinical outcome. In January 1993 the Italian National AIDS Unit began a nationwide retrospective survey of symptomatic cases of acquired immunodeficiency without HIV infection. Cases were defined as having (a) one or more clinical conditions indicating severe immunosuppression; (b) depleted CD4 T lymphocytes (fewer than 300x10 6 cells/l or proportionately less than 20% of the lymphocyte count) at the time of clinical diagnosis; (c) no known cause of immunosuppression; and (d) negative results for HIV infection on enzyme linked immunosorbent assay (ELISA) and in at least one supplementary test. This case definition was circulated to all doctors who were considered most likely to have seen such patients--namely, immunologists and specialists in infectious diseases …