To investigate the incidence, underlying diseases, and macropathological and microbiological features of invasive aspergillosis in a university hospital, the protocols of 1187 autopsies performed during the 4-year period 1993-1996 were reviewed. Invasive aspergillosis was diagnosed as the cause of death in 48 (4%) cases, four (8%) of which did not involve severe primary immunosuppression. In seven (15%) cases no pulmonary involvement was found; in six of these cases the portal of infection could not be established, whereas in one case invasive aspergillosis originated from Aspergillus peritonitis. Aspergillus grew in 42% of the samples obtained from the respiratory tracts of 32 patients with pulmonary aspergillosis and submitted within 10 days antemortem; at least one positive culture was obtained from 20 (63%) of these patients. It is concluded that the diagnosis of aspergillosis by means of culture has an appreciable sensitivity. Fatal invasive aspergillosis was rare among patients without severe immunosuppression, whereas invasive aspergillosis without pulmonary involvement was unexpectedly frequent.