Also known as: T-CELL LYMPHOCYTIC LEUKEMIA, TCELL, V109
Test Contains (LOINC): Lymphocyte Subset Panel 6 Information (48767-8), Absolute CD19 (15195-1), % Natural Killer Cells (32519-1), Absolute Natural Killer Cells (20604-5), Absolute CD45RO (34475-4), % CD45RO (41994-5), Absolute CD45RA (26759-1), % CD45RA (17157-9), Absolut
Preferred Container: EDTA (Lavender Top) Tube, Sodium Heparin (Green Top) Tube or Lithium Heparin (Green Top) Tube
Minimal Sample Volume: 0.5 mL
Handling Instructions
Transport 4 mL whole blood.
Client Transport Temperature: Critical Ambient
Specimen Stability: EDTA: Ambient: 72 hours; Refrigerated: Unacceptable; Frozen: Unacceptable Heparin: Ambient: 48 hours; Refrigerated: Unacceptable; Frozen: Unacceptable Heparin: Ambient: 48 hours; Refrigerated: Unacceptable; Frozen: Unacceptable New York State Client
Unsuitable Specimen: Clotted or hemolyzed specimens.
Frequency: Sunday, Monday, Tuesday, Wednesday, Thursday, Friday, Saturday
Expected Turn Around: 2 – 4 Days
Responsible Dept: Reference Lab
Referral Lab Code: 0095862
CPT: 86355; 86357; 86359; 86360; 86356 X 2
Methodology: Quantitative Flow Cytometry
Notes: This test is designed for enumerating the percent and absolute cell count of lymphocyte subsets in lysed whole blood. Whole blood is added to fluorochrome-labeled antibodies that bind specifically to cell surface antigens on lymphocytes. After incubation, lysing and fixation, percent and absolute count are enumerated utilizing an internal quantitation standard. Additional CBC data is not required.
During HIV infection, antiviral therapy is often initiated when the absolute CD4 count drops below 500 cells/µL. When the absolute CD4 count drops below 200 cells/µL, therapeutic prophylaxis against PCP and other opportunistic infections may be initiated. When the absolute CD4 count drops below 100 cells/µL, prophylaxis against Mycobacterium avium complex is recommended.
The CD45RA subset delineates a “naive” CD4 T-cell population. The CD45RO subset delineates a “memory” CD4 T-cell population. With disease progression in HIV-infected individuals, a decrease in CD45RA “naive” cells may be observed.
For longitudinal studies involving serial monitoring, specimen collections should be performed at the same time of day.
