Test Details: Enumeration of circulating CD4 + (helper) T-cells is an essential component of monitoring patients with immunodeficiencies including HIV infection. It is useful marker as a baseline test, post diagnosis of HIV infection and for treatment follow up.CD4 count impacts on the commencement of anti-retroviral (ARV) therapy and evaluation of response to therapy. ARV treatment is indicated when the CD4 count falls below a defined level of 200 cells/?l blood sample. Individuals with HIV typically exhibit a steady reduction of helper T lymphocyte counts as the infection progresses, with concomitant rise in CD8 counts. The decline in CD4 counts is associated with increasing clinical manifestation of immune deficiency and an increased risk of progression to AIDS