Heparin-Induced Thrombocytopenia (HIT) PF4 Antibody, IgG
Also known as: HIT IGG
Use
This test is used for initial screening of heparin-PF4 antibodies that cause Heparin-Induced Thrombocytopenia (HIT). Most cases of HIT are due to IgG antibodies against heparin-PF4 complexes. The assay has a good negative predictive value for HIT, meaning that a negative result can usually rule out HIT. However, positive results, while sensitive for HIT, are not completely specific, indicating that other clinical factors and test results should be considered. Higher optical densities in the IgG ELISA test correlate with a higher likelihood of a positive result in platelet activation assays and an increased likelihood of clinical HIT.
Special Instructions
Not provided.
Limitations
The test detects IgG antibodies and does not detect IgA or IgM antibodies which may occasionally be associated with HIT. False negatives are rare, but possible. The test alone is not diagnostic and must be considered in conjunction with clinical findings and other laboratory tests. The presence of microbially contaminated, heat-inactivated, hemolyzed, icteric, or lipemic serum specimens may lead to inconsistent results.
New York Approved
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 73818-7 - PF4 heparin cmplx IgG SerPl IA
Result Turnaround Time
1-2 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
1 mL
Minimum Volume
0.2 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Separate serum from cells as soon as possible, or within 2 hours of collection.
Storage Instructions
CRITICAL FROZEN. Keep samples frozen if submitted for multiple tests.
Causes for Rejection
Heparinized specimens
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Unacceptable |
| Refrigerated | 48 hours |
| Frozen | 2 years |
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