Days Set Up
Daily, one run per day with the exception of holidays.
The test is not run on holidays, but will be run the next business day instead.
Analytic Time

3 hours

MiChart Code
Heparin-Induced Platelet Antibody
Soft Order Code

Test Updated:


Platelet Factor 4 Antibody
PF4 Antibody
Heparin Antibodies
Heparin Associated Throbocytopenia and Thrombosis
Heparin Associated Thrombosis
Heparin Associated Thrombosis (HAT)
Heparin Dependent Antiplatelet Antibodies
Heparin Dependent Anti-Platelet Antibodies
Heparin Induced Thrombosis (HIT)
Heparin-Associated Thrombocytopenia and Thrombosis
Platelet Antibody, Heparin Dependent
Heparin Associated Platelet Antibody

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Test Overview

Test Methodology

Heparin-associated antibodies to PF4 detected by an ELISA technique.

Test Usage

Detection of heparin-dependent platelet antibodies.

Reference Range

0.000 - 0.399. Negative

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

Specimen Requirements

Collection Offsite

Collect specimen in a blue top (citrate 3.2%) tube. Mix by inversion. Specimen should arrive at lab within 3 hours of collection; transport at room temperature. Alternatively, centrifuge, aliquot plasma into a plastic tube, and freeze the specimen within 4 hours of collection. Transport frozen specimen on dry ice. Collection of the blood through lines that have been previously flushed with heparin should be avoided. If the blood must be drawn through a VAD (vascular access device), the line should be flushed with 5 mL of saline and the first 5 mL of blood or six dead space volumes of the VAD discarded.

Blue Top Tube
Normal Volume
Full 2.7 mL tube or 1 mL plasma aliquot
Minimum Volume
Full 1.8 mL tube or 1 mL plasma aliquot

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.