Test Code LAB4115 HEPARIN -PF4 IgG ANTIBODY (HIT), Serum
Specimen Type
Preferred Specimen: Serum Tube (SST, Gold, Corvac, Tiger, Red Top Tube)
Alternative Specimen: Sodium Citrate Plasma (Blue Top Tube Filled to Maximum Fill line per Protocol)
Specimen Volume
1 mL
Minimum Volume
0.5 mL
Turnaround Time
24 Hours
Test Schedule
Monday - Friday
Sample Stability
Refrigerated: 2 days
Frozen: 2 years
Method
Enzyme - Linked Immunosorbent Assay (ELISA)
Reference Ranges
<0.400 = Negative
CPT Codes
86022
Interpretation
Detection of IgG antibodies directed against heparin/platelet factor 4 complexes that are implicated in the pathogenesis of immune-mediated type II heparin-induced thrombocytopenia (HIT-II).
Clinical picture of HIT type II:
-In patients not previously exposed to heparin
-Decrease in platelet count (thrombocytopenia) of 50% or more from baseline or postoperative peak
-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