Heparin Induced Thrombocytopenia
Label Mnemonic: HIT
Epic Lab Code: LAB1088
Downtime Form: A-1a Miscellaneous Request
Hemostasis/Thrombosis
6240 RCP
356-3573
Specimen(s):
Serum
Collection Medium:
Red top tube 5 mL (Clot Activator)
Minimum:
1 mL serum
Delivery Instructions:
Deliver to laboratory within 1 hour of collection.
Testing Schedule:
HIT testing is performed daily (holidays and weekends included) at 1300. Sample must be in the lab at that time to be included in the run for that day.
Reference Range:
Negative

Critical value: Positive
Comments:
For pediatric patients <18 years of age, a Pediatric Hematology/Oncology Service Consult is required for testing approval.

It is highly recommended to use the 4T calculator to estimate risk of heparin-induced thrombocytopenia (HIT). Ordering of HIT testing is highly discouraged when the 4T score is 0-3.

Please refer to the Guidelines for Recognition and Management of Heparin Induced Thrombocytopenia which also provides the 4T scoring system.
Methodology:
Enzyme Linked Immunosorbent Assay (ELISA) used to detect antibodies to Platelet Factor 4
CPT Code:
86022