CD4/CD25, Treg Enumeration

Test Code

900994

CPT Codes
88184, 88185 (x2)<br>This test is not available for Florida, Rhode Island, Maryland, or New York patient testing<br>Restricted Client Code

Preferred Specimen

5 mL whole blood collected in EDTA (lavender-top) tube

Minimum Volume

1 mL

Instructions

After collection of the sample, draw date and time must be written on the tube. Ship sample immediately due to short stability of 72 hours. Do not freeze.

Transport Temperature

Room temperature

Specimen Stability

Room temperature: 72 hours
Refrigerated: 72 hours
Frozen: Unacceptable

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Clotted specimens; Hemolysis

Methodology
Flow Cytometry

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by the U.S. Food and Drug Administration. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Mon-Sat; Report available: 3-4 days

Reference Range

See Laboratory Report

Clinical Significance

Regulatory T-cells (Tregs) modulate immune functions and play a role in rejection and graft-verus-host disease in solid organ and stem cell transplants. This assay reports the percentage of CD4+CD25++ and CD4+CD25++CD127lo/- lymphocytes. The latter value corresponding to the functional Treg subset in blood. This test does not provide absolute lymphocyte counts for CD4+ T cells. If needed, this value could be obtained from a T-cell subset panel (e.g., Test Code 8360X.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.