Infectious complications of the acquired immune deficiency syndrome.

The cause of AIDS is unknown. In the absence of a specific etiologic agent or diagnostic test, a case can only be recognized when complications of the immune deficiency such as infection or Kaposi's sarcoma occur. Defective T-cell function is the principal immunologic defect; there are also defects, however, in B-cell function that may have some clinical significance. It has not yet been possible to reverse the immunologic deficiency, and this failure has been the principal prognostic factor in this illness. A number of the infectious complications of AIDS, however, can be diagnosed and successfully treated.