ARUP's Laboratory Test Directory

0093420: Lymphocyte Subsets Panel 4 - T-Cell Subsets Percents & Ratio, Bronchoalveolar Lavage

[ image for: Time Sensitive]
Time Sensitive
  

Test Mnemonic: LYMBAL
Methodology: Flow Cytometry

Performed: Sun-Sat

Reported: 1-3 days

Specimen Required:  
Collect: Bronchoalveolar lavage.

Transport: 5 mL bronchoalveolar lavage in a sterile container at 2-8°C.

Submit specimen according to Biological Substance, Category B, shipping guidelines.

Pediatric Collection/Transport: 3 mL bronchoalveolar lavage at 2-8°C.

Submit specimen according to Biological Substance, Category B, shipping guidelines.

Remarks: Specimens must be analyzed within 48 hours of collection.

Unacceptable Conditions: Ambient, frozen, contaminated, excess mucus, too few lymphocytes, and specimens greater than 48 hours old. Whole blood specimens (refer to 0095950).

Stability: Ambient: Unacceptable, Refrigerated: 48 hours, Frozen: Unacceptable

Reference Interval:
By report.

Interpretive Data:
Sarcoidosis is frequently associated with a predominance of CD4 positive T-Cells.  This causes an increase in the CD4/CD8 ratio.  If the CD4/CD8 ratio is >5.0 and clinical and radiographic findings are compatible with sarcoidosis, some institutions accept a diagnosis of sarcoidosis even if the biopsies are negative.  In contrast to active sarcoidosis, in extrinisic allergic alveolitis (EAA), there is a relative increase in the CD8 positive T-Cells resulting in a decrease in the CD4/CD8 ratio.  Eur Respir J, 24:1000-6; 2004.

The performance characteristics of this test were determined by ARUP Laboratories, Inc.



Note:
This assay is designed for enumerating the percents of T-Cell lymphocyte subsets in BAL and other body fluid samples (CSF, Pleural, Peritoneal).  These fluids are added to fluorochrome-labeled antibodies that bind specifically to cell surface antigens on lymphocytes.  The CD4/CD8 ratio is calculated by dividing the CD4% by the CD8%.

CPT Code(s):
88184 CD3; 88185 CD4; 88185 CD8