From the Guidelines
Acquired Immune Deficiency Syndrome (AIDS) is classified based on the Centers for Disease Control and Prevention (CDC) Staging System, which categorizes HIV-infected adults into three clinical categories: A, B, and C.
Classification Categories
- Category A: Asymptomatic, persistent generalized lymphadenopathy, or acute HIV infection, with a CD4 cell count of ≥500 cells/mm³ (≥29%) 1.
- Category B: Symptomatic disease, with conditions not listed in clinical category C, including those that are attributed to HIV infection or indicative of a defect in cell-mediated immunity, with a CD4 cell count of 200-499 cells/mm³ (14-28%) 1.
- Category C: AIDS indicator conditions, with a CD4 cell count of <200 cells/mm³ (<14%) 1.
Key Points
- The CDC classification system is used to determine the severity of HIV infection and the need for antiretroviral therapy and prophylaxis against opportunistic infections 1.
- CD4 cell counts and viral loads should be monitored regularly to assess the efficacy of antiretroviral therapy and determine the need for prophylaxis 1.
- The classification of AIDS is based on the presence of AIDS-defining conditions, which include opportunistic illnesses indicative of severe HIV disease 1.
From the Research
Classification of Acquired Immune Deficiency Syndrome (AIDS)
The classification of AIDS is based on the destruction of the immune system by the human immunodeficiency virus (HIV), leading to opportunistic infections and malignancies.
- The disease is characterized by a profound immune deficiency, resulting in opportunistic infections, autoimmune diseases, and malignancies 2.
- The clinical manifestations of AIDS can be ascribed to the destruction of helper T-cells, specifically CD4 lymphocytes, which leads to immune dysfunction 3.
- The risk of developing opportunistic infections and malignancies typical of AIDS increases progressively as CD4 counts fall below 200 cells/mm3 2, 3.
- AIDS is classified as a distinct clinical entity characterized by opportunistic infections and Kaposi's sarcoma (KS), occurring in selected groups of the population but with an ever-increasing spectrum 4.
- The disease is caused by a retrovirus, termed human immunodeficiency virus (HIV), and is a blood-borne disease with sexual, parenteral, and perinatal modes of transmission 3, 5.
Key Features of AIDS Classification
- Destruction of the immune system by HIV
- Opportunistic infections and malignancies
- Profound immune deficiency
- CD4 count below 200 cells/mm3
- Characteristic clinical manifestations, including pneumonia, dysphagia/odynophagia, diarrhea, neurological symptoms, fever, wasting, anemia, and visual loss 2
- Increased risk of autoimmune diseases and malignancies, such as Kaposi's sarcoma and non-Hodgkin's lymphoma 2, 3