Lymphocyte Surface Marker Analysis
CD4 counts and CD8 counts are routinely used in the monitoring of HIV infection. The use of CD4 count as a surrogate marker for the diagnosis of HIV infection is unhelpful and constitutes poor medical practice.
A low CD4 count is not diagnostic of HIV infections, occurring in a wide variety of other conditions such as primary immunodeficiency, viral and bacterial infection, lupus and steroid therapy. Circulating peripheral blood lymphocytes from patients with suspected (or known) B cell, T cell or B and T cell immunodeficiencies are tested with a panel which includes B cell (CD19), T Cell (CD3/4 CD3/8) and NK cell markers (CD16/56).
- Children with suspected or known severe combined immunodeficiency are assessed for their B and T cell phenotype.
- T cell numbers on children with known or suspected DiGeorge syndrome/ 22q deletion.
- Patients with suspected B cell immunodeficiency/antibody deficiency
Lymphocyte subset analysis is also indicated in patients receiving rituximab/ anti-CD20 monoclonal antibody treatment for monitoring of B cell numbers.
EDTA Blood – Samples must not be refrigerated or centrifuged and must arrive before 4pm on Fridays
Storage and Transport
All requests for lymphocyte surface marker analysis, other than for HIV or anti-CD20 monoclonal antibody treatment monitoring should be discussed with the laboratory’s medical staff and/or Senior Clinical Scientist.
Turn Around Time