Acquired immune deficiency syndrome. A deadly new disease.

The acquired immune deficiency syndrome (AIDS) represents a new epidemic of major proportions. Risk factors include homosexuality, intravenous drug abuse, Haitian descent, and multiple transfusion in the presence of hemophilia A. The etiology of AIDS remains unknown, but there is increasing evidence implicating a transmissible infectious agent and/or multiple antigenic exposures inducing a loss of immunoregulation. In a high-risk patient, the features of weight loss, generalized lymphadenopathy, and fever should arouse suspicion of AIDS. Diagnostic confirmation includes demonstration of reduced numbers of T lymphocytes with reversal of helper-suppressor T-lymphocyte ratio, presence of unusual opportunistic infections, and a progressive downhill course. The most common infection in AIDS is Pneumocystis carinii pneumonia. Treatment failures with trimethoprim-sulfamethoxazole (Bactrim, Septra) are common; pentamidine isethionate (Lomidine) may be more effective in eradicating the infection. In spite of initial improvement, recurrences of P carinii pneumonia and other opportunistic infections are common. In addition, other protozoan, viral, fungal, and atypical mycobacterial infections are frequent in patients with AIDS. Finally, rare neoplasms such as Kaposi's sarcoma and B-cell lymphoma, including primary lymphoma of the brain, are also being recognized as complications. At present there is no specific therapy for AIDS, and the disease is usually fatal. Continued research will hopefully result in immunomodulation techniques and specific vaccines to combat this serious epidemic.