Heparin-Induced Thrombocytopenia (HIT) Antibodies, PF4 IgG/IgM/IgA by ELISA with Reflex to Serotonin Release Assay (Heparin Dependent Platelet Antibody), Unfractionated Heparin
0051249
Ordering Recommendation
 
Mnemonic
PLT HAT R
Methodology
Semi-Quantitative Enzyme-Linked Immunosorbent Assay/Serotonin Release Assay
Performed
Sun-Sat
Reported
1-10 days  
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
Specimen Required
Patient Preparation
  
Collect
Plain red or serum separator tube (SST).  
Specimen Preparation
Separate serum or plasma from cells ASAP or within 2 hours of collection. Transfer 3 mL serum to an ARUP Standard Transport Tube. (Min: 2 mL) Also acceptable: ACD or sodium citrated plasma.  
Storage/Transport Temperature
CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered. Ship on dry ice.  
Unacceptable Conditions
Heparinized specimens.  
Remarks
 
Stability
After separation from cells: Ambient: Unacceptable; Refrigerated: Unacceptable; Frozen: 1 month  
Reference Interval
Effective November 14, 2011
 
Test Number Components Reference Interval
0051052Heparin-​Induced Thrombocytopenia (HIT) Antibodies, PF4 IgG/IgM/IgA by ELISA 0.399 OD or less
2005631Serotonin Release Assay (Heparin Dependent Platelet Antibody), Unfractionated Heparin By report
Interpretive Data
By itself, a positive result on this ELISA test is relatively non-specific for a clinical diagnosis of heparin-associated antibody syndrome (HIT) (frequent false-positives) and a negative result does not exclude a diagnosis of HIT if the clinical suspicion remains high (occasional false-negatives). Results should be used in conjunction with clinical findings, platelet counts and other laboratory results.

For a clinical scoring system to assess pretest probability of HIT and other guidance for diagnosing HIT, refer to the Heparin-Associated Antibody Syndrome topic at arupconsult.com.  
Note
Microbially contaminated, heat-inactivated, hemolyzed, icteric, or lipemic sera may give inconsistent results. Positive ELISA results are relatively non-specific for a clinical diagnosis of HIT.
If ELISA result is positive, then Serotonin Release Assay (a functional assay with greater specificity for a clinical diagnosis of HIT syndrome) will be added. Additional charges apply.
CPT Code(s)
86022; if reflexed add 86022
Components
Component Test Code*Component Chart Name
0051052Heparin-Induced Thrombocytopenia Abs PF4
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • HAT
  • Heparin Induced Antibodies
  • Heparin PF4 Antibody
  • Heparin-Associated Antibody
  • HIPA
  • HIT Antibodies Reflex toSRA
  • HIT IgG, IgM, IgA and SRA
  • HIT PF4 Antibodies Reflex t SRA
  • HITA
  • Type II HIT