Measures CD4 (helper) and CD8 (cytotoxic) T cells and their ratio using flow cytometry.
Used to monitor immune status in HIV and other immune deficiencies, and after organ or bone marrow transplant.
Recurrent or unusual infections, or monitoring of immune status — as advised by a doctor.
No fasting needed.
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A low ratio suggests the immune system is under strain, as in untreated HIV.
No fasting is needed. You can eat and drink normally unless your doctor has advised otherwise.
Blood or bone marrow sample (EDTA/heparin tube) as advised by your haematologist.
Usually within 31–55 hours after the sample reaches the lab. You will receive the report online.