HIV infection in older patients: when to suspect the unexpected.

The number of AIDS patients over age 60 has risen steadily in the past decade. The number of transfusion-acquired AIDS cases probably has peaked--or will soon peak. Homosexual (or bisexual) behavior remains the predominant risk factor for AIDS until the seventh decade. Disease progression appears to be more rapid in the elderly, although the observed shorter survival time may result from a delay in diagnosis. Symptoms of HIV infection are often nonspecific, such as fatigue, anorexia, weight loss, and decreased physical and cognitive function. The five most common opportunistic infections in older HIV-infected patients are Pneumocystis carinii pneumonia, tuberculosis, Mycobacterium avium complex, herpes zoster, and cytomegalovirus. A number of features of HIV-related dementia may help to distinguish it from Alzheimer's disease.