Cerebral toxoplasmosis and lymphoma in patients with acquired immunodeficiency syndrome

16 Patients with central nervous system (CNS) complications of the acquired immunodeficiency syndrome (AIDS) are described. All patients were male homosexuals. The most common demonstrable lesion in the parenchyma was toxoplasmosis, which produced an area of focal oedema, usually containing a central zone of nodular or ring-shaped enhancement. Cerebral atrophy was also a common finding. One patient had diffuse peri-ventricular lymphomatous infiltration, and a further two patients had both cerebral toxoplasmosis and lymphoma. A delayed "double dose" contrast examination appears to be the most accurate method of outlining the total extent of CNS disease in these patients.