HIT - Overview: Heparin-PF4 Antibody (HIT), Serum

Test Catalog

Test ID: HIT    
Heparin-PF4 Antibody (HIT), Serum

Useful For Suggests clinical disorders or settings where the test may be helpful

Evaluation of possible immune-mediated type II heparin-induced thrombocytopenia (HIT-II) which should be suspected for the following patients:

-Patients not previously exposed to heparin, the development of absolute thrombocytopenia or decrease in platelet count of > or =50% from baseline or postoperative peak with the onset of thrombocytopenia beginning approximately 5 to 10 days after initiation of heparin. This may or may not be associated with new or progressive thrombosis in patients treated with heparin.

-Patients previously exposed to heparin (especially within the preceding 100 days), in addition to the above findings, the onset of thrombocytopenia could occur within 24 to 48 hours after reexposure to heparin.


In patients with prior suspected or documented heparin-induced thrombocytopenia (HIT), with or without thrombosis, assay for presence of human platelet factor 4 (H/PF4) antibody may be useful in assessment of the risk of recurrence of HIT with additional exposure to heparin, however, prospective data are limited.

Method Name A short description of the method used to perform the test

Enzyme-Linked Immunosorbent Assay (ELISA)

NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.


Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name

Heparin-PF4 Ab (HIT), S

Aliases Lists additional common names for a test, as an aid in searching

Heparin Induced Antibody
Heparin-Dependent Antibody