Before presenting to the Mayo Clinic, a 24-year-old white woman had received 35 transfusions of blood products over a 72-hour period in February 1981. Two and one half years later, the diagnosis of polymicrobial cholangitis (Cryptosporidium, Candida albicans, and Klebsiella pneumoniae) was established. Further evaluation demonstrated profound helper T lymphocyte suppression, disseminated Mycobacterium avium-intracellular infection with mycobacteremia, and Kaposi's sarcoma of lymphoid tissue, confirming a diagnosis of acquired immune deficiency syndrome (AIDS). This case represents an unusual infectious complication of AIDS. Additionally, this is believed to be the first report of Kaposi's sarcoma occurring in a patient with AIDS associated with blood product transfusion.