Acquired immune deficiency syndrome, leading to opportunistic infections, Kaposi's sarcoma, and other malignancies.

In early 1981 several cases of Pneumocystis carinii pneumonia in young male homosexuals were recognized. Between then and the end of 1982 almost 800 cases of serious opportunistic infections and malignancies have occurred in this group and now in other groups as well. The most common malignant disease to be seen is the otherwise uncommon endothelial cell sarcoma, Kaposi's sarcoma. The underlying abnormality, both to the opportunistic infections and the malignancies, is one of acquired immune deficiency of the cell mediated variety. Other common factors in affected persons are evidence of cytomegalovirus infection, a previous history of various sexually transmitted diseases and lifestyle characteristics. Recent evidence of the abnormality amongst Haitian immigrants, haemophiliacs, heterosexuals and neonates has enormously complicated what is already a perplexing problem, the understanding of which will shed light on the relationship between immunity, infectious diseases and malignancy.