Veripath Test Directory

Epic Test Name HIT (Heparin Induced Thrombocytopenia) Ab
Synonyms HIT
Description Heparin-induced thrombocytopenia (HIT) is a pro-thrombotic, immune-mediated disorder that can cause morbidity and mortality in patients receiving heparin therapy. HIT is caused by the development of platelet-activating antibodies, mostly directed against platelet factor 4-heparin complexes (PF4/H). HIT is suspected when patients treated with unfractionated heparin (UFH) or low molecular weight heparin (LMWH) show a decrease of platelet counts greater than 50% from the baseline, typically between day 5 and 10 from the initiation of the anticoagulant treatment. Cases of early-onset HIT and delayed-onset HIT have also been reported. Management of HIT involves cessation of heparin and initiation of an alternative anticoagulant.
Specimen Requirements 
Container 3 mL-3.2 % Sodium Citrate tube (blue top)
Specimen Type Blood
Preferred Collection Volume 3 mL
Minimum Collection Volume Adult: 2 mL, Neonates : 2 mL
Collection Instructions None
Specimen Handling In-house patients, transport at room temperature
Outside clients, follow collection instructions, and the steps below:
1. Spin blue top tube to generate platelet-poor plasma. Remove plasma avoiding
platelet/buffy coat layer.
2. Plasma must be frozen within 4 hours of collection. CRITICAL WARNING: Specimens
must remain frozen until ready to test. Submit separate aliquots when multiple tests are
ordered on the same patient specimen.
3. Transport frozen.
Rejection Criteria Plasma hemolyzed or thawed.
Methodology Immunoturbidimetry
Reference Range <1.0 U/mL. See Interpretation.
CPT Code(s) 86022 x 2, 85390
Department Hemostasis/Coagulation
Contact Information Hemostasis Lab; 214-633-4959, Customer Service: 214-633-5227
Turn Around Time1 day
Performed Sunday - Saturday
Performed by Hemostasis Lab
Updated/Reviewed 10/26/2017