Test Overview

Test Methodology

Solid Phase Assays

Test Usage

In addition to HLA high resolution typing, patients are screened for preformed anti-HLA antibodies; the detection of anti-HLA antibodies directed to possible mismatches in less ideal donors is related with delay in the platelets and neutrophil engraftment and even with graft rejection. Panel reactivity antibody (PRA) indicates the degree of reactivity of tested serum in terms of percent of positive reactions when tested against a panel of known HLA phenotypes.

Reference Range*

For positive results, the report will define the detected HLA antibody specificities. For negative results, 0% PRA will be reported.

* Reference ranges may change over time. Please refer to the original patient report when evaluating results.

Test Details

Days Test Performed

Monday - Friday, 8:00am - 4:30pm

Analytic Time

5 days

Soft Order Code




Allogenic PRA
Allogenic Bone Marrow Transplant
HLA Antibody Screen Mixed
HLA Antibody Screening Class I & II

+ See More



Looking to Order a Test?

We’ve provided helpful links to make ordering easy.

Find a Requisition

All specimens should be accompanied by a requisition.

Submitting Specimens

Learn about how to properly label and where to ship specimens.

Order Kits and Supplies

MLabs provides all the supplies necessary for the collection of specimens.

Test FAQ

Visit our provider FAQ and learn about common questions to ordering tests.

Specimen Requirements


Yellow Top Tube
Red Top Tube

Normal Volume

5 mL serum

Minimum Volume

3 mL serum

Additional Information

The Class I & II screening assay is performed first and detects the presence/absence of HLA antibodies. If the screening assay is positive, a high specificity and sensitivity single HLA Antigen assay will be performed to identify the specificity of the anti-HLA antibody present in the serum sample from the recipient. By ordering this test the clinician acknowledges that additional reflex testing will be performed and billed at a separate additional charge if indicated.

Billing Information

Fee Codes

CPT Code


Reflex Fee Code

37962, 37963

Have More Billing Questions?

Explore our helpful billing resources:

Billing Resources

Billing FAQ