Test Overview

Test Usage

To detect IgG immunoglobulin and/or complement adherence to red cells, as seen in immune hemolytic anemia or in a delayed hemolytic transfusion reaction. Positive tests will be further evaluated for bound and unbound antibody specificities associated with Cold Hemagglutinin Disease, Warm Autoimmune Hemolytic Anemia, and delayed reaction to transfusion. Positive tests will be further evaluated to determine the specific type(s) of protein adhering to the red cells and present in the serum (indirect test).

Reference Range*


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

Test Limitations

Use of red top tubes or serum separator tubes may cause false positive reactions.

Test Details

Days Test Performed

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

Analytic Time

1 - 72 hours

Soft Order Code




Coombs Antibody
Coombs Test
Coombs' Antibody
Coombs' Test
DAT Study
Direct Coombs`

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Blood Bank

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Specimen Requirements

Offsite Collection Instructions

Collect specimens in two pink top tubes. Send intact specimens at room temperature. Specimens are unacceptable if collected in serum separator tube, contaminated, or grossly hemolyzed. Specimens sent for Blood Bank testing cannot be split for use by other laboratories.


Pink Top Tube

Normal Volume

7 mL whole blood

Minimum Volume

7 mL whole blood

Additional Information

If the DAT is positive at 1+ or less, additional antiglobulin testing and an antibody screen will be performed at an additional charge (for subsequent specimens on the same patient that are positive at 1+ or less, the antibody screen will not be performed). If the DAT is positive at 2+ or greater, monospecific testing and an eluate/absorption panel will be performed at an additional charge. If the antibody screen is positive, an RBC identification panel will be performed at an additional charge. Tests for drug directed antibodies performed following consultation. 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

86880 x2

Reflex Fee Code

21257, 21253, 21267

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