CD4+ T-Cell Recent Thymic Emigrants (RTEs)
Ordering Recommendation
Assess thymic function in suspected severe combined immunodeficiency (SCID), DiGeorge syndrome and other T- cell immune deficiency disorders. Evaluate immune reconstitution during highly active antiviral therapy (HAART) in HIV patients and post chemotherapy and hematopoietic cell transplant.
Methodology
Quantitative Flow Cytometry
Performed
Sun-Sat
Reported
1-3 days
New York DOH Approval Status
Specimen Required
Lavender (EDTA) or Green (Sodium or Lithium Heparin).
New York State Clients: Lavender (EDTA).
Transport 4 mL whole blood. (Min: 0.5 mL)
New York State Clients: Transport 3 mL whole blood in the original collection tube. (Min: 1.5 mL) Do not send to ARUP Laboratories. Specimen must be received at performing laboratory within 48 hours of collection. For specimen requirements and direct submission instructions please contact ARUP Referral Testing at (800) 242-2787, ext. 5145.
Refrigerated. Also acceptable: Room temperature.
New York State Clients: Room temperature.
Cord blood. Specimens older than 72 hours. Clotted or hemolyzed specimens.
Specimens must be analyzed within 72 hours of collection.
New York State Clients: Specimens must be analyzed within 48 hours of collection.
Ambient: 72 hours; Refrigerated: 72 hours; Frozen: Unacceptable
New York State Clients: Ambient: 48 hours; Refrigerated: Unacceptable; Frozen: Unacceptable
Reference Interval
Test Number |
Components |
Reference Interval |
||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
% CD4+CD31+CD45RA+ (RTEs) |
|
|||||||||||||||||||||
Abs CD4+CD31+CD45RA+ (RTEs) |
|
Interpretive Data
Recent thymic emigrants (RTEs) CD4+CD45RA+CD31+ represent naive T-cells recently migrated from the thymus and are measured as a percent of CD4+ T-cells. A decrease or absence of RTEs is associated with a decrease or loss of thymic output in children, as seen in severe combined immunodeficiency (SCID), DiGeorge syndrome and other cellular immune deficiency disorders. RTE results should be interpreted with caution in adults due to age-related decline in thymic function. RTE assessment may also be used to evaluate immune reconstitution after hematopoietic cell transplant, post chemotherapy and in HIV patients undergoing highly active antiviral therapy (HAART). Serial measurement is recommended.
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.
Laboratory Developed Test (LDT)
Note
Hotline History
CPT Codes
86356 x3
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
2010180 | % CD4+CD31+CD45RA+ (RTEs) | 8123-2 |
2010181 | Abs CD4+CD31+CD45RA+ (RTEs) | 24467-3 |