Heparin Induced Platelet Antibody (HIT)

Message

Sendout, Machaon test code: P1181

Test Code

LAB5210542

Alias/See Also

HIT-AB (Screen)
PF4 antibody
Platelet factor 4 antibody
P1181
P3060

CPT Codes
83520

Preferred Specimen

1 mL serum from a red tube

Minimum Volume

0.5 mL

Other Acceptable Specimens

Light blue (sodium citrate) tube

Instructions

Processing Requirements:
a. Spin red top (approx. 15 minutes at 3500 rpm) in centrifuge within 2 hours of draw.
b. Transfer approx. 1mL serum into clear aliquot sample tube and cap.
c. Label tube with patient label created in EPIC and seal with parafilm.
d. Store aliquot in ambient rack in Reference department. (Sample is stable at room temp for 7 days, refrigerated 7 days, and <-20 frozen – 6 months).

Transport Container

Red top

Transport Temperature

Room Temperature

Specimen Stability

Room Temp: 7 days
Refrigerated : 7 days
Frozen : 6 months

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Sample contamination, sample compromised

Methodology
ELISA screening

FDA Status
Cleared

Setup Schedule

Daily

Report Available

<24 hours of receipt at testing facility

Reference Range

Included with report

Clinical Significance

The wp-HIPA (washed platelet heparin-induced platelet activation) test is a quantitative, platelet activation assay capable of detecting clinically significant HIT antibodies. Washed platelet assays, such as the serotonin release assay (SRA) and heparin-induced platelet activation (wp-HIPA) are the reference or GOLD STANDARD methods for diagnosing HIT [1, 4]. Both assays are sensitive and specific for HIT because they ONLY detect antibodies that are capable of activating platelets [1, 3]. The wp-HIPA test is useful in the diagnosis of patients with weakly positive PF4 ELISA results (OD 0.4 – 1.0) and patients with low to intermediate 4T Scores[1, 5]. This test enhances specificity for HIT antibodies by testing 4 concentrations of heparin. This solid-phase ELISA detects the presence of anti-platelet factor 4 (PF4) antibodies in patient serum. Both optical density (OD) and interpretation are reported since OD correlates well with the likelihood of HIT. This test reflexes automatically to the wp-HIPA confirmation assay.

Performing Laboratory
Machaon Diagnostic, Inc.

Additional Information
Heparin Antibody (HIT) Screen – PF4 (reflex to confirmation)

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.