von Willebrand Panel

Test Code

91242

CPT Codes
85240, 85246, 85245, 85730

Includes

Factor VIII Activity, Clotting
von Willebrand Factor Antigen
Ristocetin Cofactor
Partial Thromboplastin Time, Activated

Preferred Specimen

3.6 mL platelet-poor plasma collected in 3.2% sodium citrate (light blue-top) tube

Minimum Volume

1.8 mL

Instructions

See individual assays

Transport Temperature

Frozen

Specimen Stability

Room temperature: Unacceptable
Refrigerated: Unacceptable
Frozen: 14 days

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

Hemolysis • Lipemia

Methodology
Immunoturbidimetric Assay • Photometric Clot Detection • Photo-Optical Clot Detection • Platelet Agglutination

Setup Schedule

See individual assays

Clinical Significance

von Willebrand Disease (VWD) is the most common hereditary bleeding disorder and it may also be acquired. von Willebrand Factor (VWF) is critical for normal hemostasis; mediating platelet adhesion to the damaged endothelium and protecting Factor VIII from proteolytic degradation in circulation. Types 1 and 3 VWD are characterized by a decrease in both VWF quantitative and functional assays, whereas type 2 variants are characterized by defects in functional assays or VWF multimeric studies. Because of the numerous variants of VWD which may have different treatments, multiple assays are often necessary to identify the type of VWD.

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.