ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS)
The most severe manifestation of infection with the Human Immunodeficiency Virus (HIV). The Centers for Disease Control and Prevention (CDC)<!-- (see) --> lists numerous opportunistic infections and neoplasms (cancers) that, in the presence of HIV infection, constitute an AIDS diagnosis. There are also instances of presumptive diagnoses when a person's HIV status is unknown or not sought. This was especially true before 1985 when there was no HIV-antibody test. In 1993, CDC expanded the criteria for an AIDS diagnosis to include CD4+<!-- (see) --> T-cell count at or below 200 cells per microliter in the presence of HIV infection. In persons (age 5 and older) with normally functioning immune systems, CD4+ T-cell counts usually range from 500-1,500 cells per microliter. Persons living with AIDS often have infections of the lungs, brain, eyes, and other organs, and frequently suffer debilitating weight loss, diarrhea<!-- (see) -->, and a type of cancer called Kaposi's Sarcoma<!-- (see) -->. See HIV Disease; Opportunistic Infection; AIDS Wasting Syndrome.
A progressive weakening of the immune system accompanied by one or more indicator diseases (opportunistic infections) -- including Kaposi's sarcoma, invasive cervical cancer, pneumocystis carinii pneumonia, and wasting syndrome. In AIDS, common immune system deterioration is marked by a depletion of T-helper (T 4/CD4) cells, which help stimulate antibody production. AIDS is commonly thought to be caused by a retrovirus, HIV.
