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HelpTest Code 505008 Helper T-Lymphocyte Marker CD4 - Labcorp
Additional Codes
- CD4 Count
- CD4+ Lymphocytes
- T4 Helper Cells
- 505008
Specimen Type
Whole Blood Lavender-top (EDTA) tube and Whole blood Yellow-top (ACD-A or ACD-B) tube
Collection
Invert tube 8 to 10 times immediately after collection. To preserve cellular viability, collect specimen so it will arrive in the laboratory within 48 hours of collection. Indicate date and time of venipuncture on the tube(s) and on the test request form.
Storage Instructions
Maintain specimen at room temperature. Do not freeze or refrigerate.
Stability Requirements
|
Temperature |
Period |
|---|---|
|
Room temperature |
2 days |
|
Refrigerated |
Unstable |
|
Frozen |
Unstable |
|
Freeze/thaw cycles |
Unstable |
Causes for Rejection
Hemolysis; specimen refrigerated or frozen; clotted specimen; contaminated specimen
Test Details
Use: Monitor patient's helper/inducer T-cell status
Methodology: Flow cytometry
Reference Interval: Reference intervals for adults have been established by the laboratory. See table.
CD4+ Reference Intervals for Lymphocyte Immunophenotyping
|
Age |
95% Confidence Interval |
|||
|---|---|---|---|---|
|
Percentage |
Cells/mm³ |
|||
|
Minimum |
Maximum |
Minimum |
Maximum |
|
|
Pediatric reference intervals are from Comans-Bitter WM, de Groot R, van den Beemd R, et al. Immunophenotyping of blood lymphocytes in childhood. Reference values for lymphocyte subpopulations. J Pediatrics. 1997 Mar; 130(3):388-393. |
||||
|
Neonates |
17 |
52 |
400 |
3500 |
|
1 wk to 2 m |
41 |
68 |
1700 |
5300 |
|
2 to 5 m |
33 |
58 |
1500 |
5000 |
|
5 to 9 m |
33 |
58 |
1400 |
5100 |
|
9 to 15 m |
31 |
54 |
1000 |
4600 |
|
15 to 24 m |
25 |
50 |
900 |
5500 |
|
2 to 5 y |
23 |
48 |
500 |
2400 |
|
5 to 10 y |
27 |
53 |
300 |
2000 |
|
10 to 16 y |
25 |
48 |
400 |
2100 |
|
Adults |
31 |
59 |
359 |
1519 |
Additional Information
HIV-1 infection results in a decrease of CD4 T cells, an increase of CD8 T cells, a decrease in the CD4:CD8 ratio, and a progressive destruction of immune function. In HIV-1 seropositive patients, enumeration of CD4 T cells may be used for prognostic purposes and to monitor disease progression and antiretroviral therapy.
Expected Turnaround Time
1 - 3 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary
Test Includes
Percentage of CD4+; absolute CD4+ (helper/inducer); absolute lymphocyte count; CBC