Days Set Up
Monday - Saturday
Analytic Time

1 - 3 days

MiChart Code
Heparin Induced Serotonin Release Assay
Soft Order Code

Test Updated:


Heparin Antibodies
Heparin Associated Thrombocytopenia and Thrombosis
Heparin Associated Thrombosis (HAT)
Heparin Dependent
Heparin Dependent Antiplatelet Antibodies
Heparin Induced Serotonin Release Assay
Heparin Induced Thrombosis (HIT)
Heparin-Associated Throbocytopenia and Thrombosis
Heparin-Associated Thrombosis (HAT)
Heparin-Dependent Antiplatelet Antibodies
Heparin Serotonin Release Assay
Heparin-Induced Thrombosis (HIT)
Platelet Aggregation Factor
Platelet Aggregation Factor, Heparin Dependent
SRA (Serotonin Release Assay)
Serotonin Release, Heparin-Induced
Serotonin Secretion Assay for HAT
Serotonin Releasing Assay
Heparin-Dependent Platelet Antibody (SRA) - Unfractionated Heparin

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Test Overview

Test Methodology

(14)C-Serotonin Release Assay (SRA)

Test Usage

Detection of heparin-dependent platelet antibodies.

Reference Range

Negative. A positive result requires >20% release of serotonin with low dose heparin and

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

Specimen Requirements

Collection Onsite

Collect specimen in a red top tube; do not use SST tube. Specify Lovenox® (LMWH) or Unfractionated Heparin (UFH).

Collection Offsite

Collect specimen in a red top tube; do not use SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate. Citrated or ACD plasma is acceptable if serum is not available. Specify Lovenox® (LMWH) or Unfractionated Heparin (UFH).

Red Top Tube
Normal Volume
5 mL serum
Minimum Volume
1 mL serum

Billing Information

CPT Code
Pro Fee Code

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Our High Standard

Quality that sets us apart

As the reference laboratory division of Michigan Medicine's Department of Pathology, MLabs shares the institution's commitment to applying established quality principles to clinical laboratory testing. Like other large organizations in complex, consequential fields, we rely on an established approach to monitor quality throughout the testing process.