HIV antigen, HIV antibody and serum interferon in a patient with encephalopathy.

Acute encephalopathy was associated with the presence of human immunodeficiency virus type I (HIV I) antigen and seroconversion to anti-HIV I in a 27-year-old homosexual man. Examination of consecutive sera from the patient revealed circulating interferon (IFN) alpha which became detectable with the appearance of HIV I antigen but before development of anti-HIV I. Serum IFN was present for only a limited time and was not demonstrable after neurological symptoms resolved. It may be speculated that circulating antiviral activity contributed to the clinical manifestations of acute HIV I infection.