Test Name: CD4 T CELL TEST
EPIC Search Term: LABTCD4
Synonyms: Tube directly to tube station 530. This test requires its own tube. Flow cytometry, Immunophenotyping, TCD4, T-Cell percentage, T cell count, CD4 T cell percentage, CD$ T cell count, A&I, IAR, Immunology
Panel Composition: Percentages Absolute Counts per Microliters of the following:
CD3+ (Total T Cells)
CD3+CD4+ (CD4+ T Cells)
Preferred Container: 1 x Purple EDTA Tube
Sample Type: Whole Blood Venipuncture; Central line, Arterial, Capillary, Cord Blood
Draw Volume: 1.0
Minimum Volume: 0.5
Collection Instructions: 1. CBC must be DRAWN AT SAME TIME as this specimen.

2. CBC should be performed at TCH.

3. For day- and time-sensitive considerations--see 'Testing Frequency' and 'Collection Cut-Off Time' instructions.

4. Tube specimen and Lab Labels (& completed requisition if downtime) to IAR lab (p-tube station #530).


5. The Woodlands/West Campus/Sugarland Campuses: okay to send specimens anytime Monday - Thursday. On Fridays, specimens must be on the courier run at least by noon to Main Campus taking into account that the sample transit time could be anywhere between 3-4 hours before the samples arrive in the A&I lab and lab closing time is between 5 5:30pm
Collection Cut-Off Time: 1. CBC must be DRAWN AT SAME TIME as this specimen.

2. CBC should be performed at TCH.

3. For day- and time-sensitive considerations--see 'Testing Frequency' and 'Collection Cut-Off Time' instructions.

4. Tube specimen and Lab Labels (& completed requisition if downtime) to IAR lab (p-tube station #530).

5. The Woodlands/West Campus/Sugarland Campuses: On Fridays, specimens must be on the courier run at least by noon to Main Campus taking into account that the sample transit time could be anywhere between 3-4 hours before the samples arrive in the A&I lab and lab closing time is between 5 5:30pm.
Special Collection Instructions: 1. Test is performed from Monday - 1pm Friday, except (TCH, BCM) holidays.

2. Test is NOT available after 1pm Friday, on Saturdays, or on Sunday when Monday is a holiday.

3. West Campus specimens must be received in lab by 11am OR patient must arrive in collection lab by 10am.

4. Specimens drawn at other times (Sundays, holidays when next day is a work day) may be processed if accompanied by a clearly-labeled, time-matched normal (control) specimen (with CBC).
Specimen Information: 1. Room Temperature specimens.

2. Do NOT centrifuge.

3. Do NOT store.
Specimen Transport: Time sensitive test: samples must be processed within 30 hours of collection.
Required Information: 1. If CBC not performed at TCH, please fax results to 832-825-1260.

2. Requisition must include ordering care provider contact information (phone or email).

3. Tube specimen & Lab Labels (or completed requisition for downtime) to IAR (p-tube station #530).
Required Forms: For downtimes complete Allergy/Immunology Service 'Request for Lymphocyte Analysis' form must accompany specimen.
Causes for Rejection: 1. Samples arriving after 1pm Friday

2. Specimens older than 30 hours in EDTA

3. Frozen or refrigerated specimens.

4. Specimen container broken, leaked or contaminated with blood; Clotting; Significant Hemolysis

5. Extremely low ALC (<150/ml)
Testing Frequency: Monday-1pm Friday, except (TCH & BCM) holidays
Expected Turn Around Time: 7 working days
Clinical Application: To evaluate immunosuppressive therapies in transplantation and autoimmune diseases, HIV-positive patients and congenital immunodeficiency
Methodology: Flow cytometry
Reference Ranges: Adult normal ranges: Percentages (%) and Counts per mcL
CD3+ (Total T Cells): 60 - 89 (%) 323 2513 (counts/mcL)
CD3+CD4+ (CD4+ T Cells): 29 69 (%) 109 1764 (counts/mcL)
Unit of Measure: Percentages Absolute Counts per Microliters
Test Performed By: Allergy & Immunology Laboratory, 832-824-1319
1102 Bates
Suite 330 MC: FC330
Houston, TX 77030-2399
Lab Section: Allergy & Immunology Lab