Within one year a 46-year-old HIV-positive man developed Pneumocystis carinii pneumonia, candida oesophagitis and recurrent mucocutaneous herpes simplex infections. He finally developed a constant fever without any infection-localizing features. There was pancytopenia, increased activities of the transaminases, lactate dehydrogenase, amylase and lipase, as well as diffuse ST-segment changes in the ECG and discrete pulmonary infiltrates. The anti-toxoplasmosis titre was 8 IU/ml. Despite extensive diagnostic tests no firm diagnosis could be established. The pulmonary infiltrate and the fever regressed under antibiotic treatment with co-trimoxazole. Two months later his general condition deteriorated again with some disorientation and subfebrile temperature, epididymitis and renewed rise in abnormal laboratory values. For the first time computed tomography showed some punctate contrast-medium concentrations in the subcortical area and the medulla. The patient died on the same day. Histological material obtained at the time of autopsy revealed pseudocysts with Toxoplasma gondii and necrotizing inflammation in the brain, myocardium and lungs, as well as the entire gastrointestinal and urogenital tracts. In addition, cytomegalovirus infection of the lung and adrenals was demonstrated. Anti-toxoplasmosis IgG titre, determined postmortem, again registered a marked rise to 251 IU/ml. This suggests that there was reactivation of the toxoplasmosis as part of the immunosuppression process.