Utility: 1) Monitor treatment efficacy for human immunodeficiency virus (HIV).
2) Establish decision points for antiviral therapeutic initiation.
Specimen: 1 - 4 mL peripheral blood in sodium heparin (green top).
CPT codes: 86359, 86360, 88184, 88185, 88187.
Clinical indication/general description
Human immunodeficiency virus type 1 (HIV-1) infects CD4+ T cells (helper T cells) leading to their premature death. The subsequent decrease in the number of CD4+ T cells results in the Acquired Immunodeficiency Syndrome (AIDS) and an increased susceptibility to opportunistic infections. Monitoring the number of CD4+ T cells is useful to assess the risk of infection and to monitor the response to anti-retroviral therapy.
Flow cytometric detection of CD4 and CD8 cells is used to determine the absolute CD4 and CD8 counts. AIDS presents with a severe reduction or absence of T helper cells (CD3+CD4+) with an absolute CD4 value < 200cells/ml, a low CD4:CD8 ratio (typically <1.00) and infections.
Note: The CD3 antigen exclusively is expressed on T cells.