Evolution of the incidence and aetiology of fever of unknown origin (FUO), and survival in HIV-infected patients after HAART (Highly Active Antiretroviral Therapy).

Background: Fever of unknown origin (FUO) is common among HIV-infected patients with a CD4+ T-lymphocyte cell count below 200 cells/ml. The use of HAART has transformed the evolution of AIDS and related diseases.

Design And Method: Case-control study, nested on a historical cohort of 3777 HIV-infected patients who were attended at "12 de Octubre" University Hospital in Madrid, Spain, between 1994 and 2000.