Ordering Recommendation

Order in conjunction with von Willebrand Factor Antigen (0030285) and Factor VIII, Activity (0030095) as part of initial workup for suspected von Willebrand disease (VWD). Also useful for monitoring treatment in patients with VWD.

Mnemonic

RCF

Methodology

Platelet Agglutination

Performed

Mon-Sat

Reported

1-3 days

New York DOH Approval Status

This test is New York DOH approved.

Specimen Required

Patient Preparation
Collect

Lt. blue (sodium citrate). Refer to Specimen Handling at aruplab.com for hemostasis/thrombosis specimen handling guidelines.

Specimen Preparation

Transfer  1.5  mL platelet-poor plasma to an ARUP Standard Transport Tube. (Min: 1 mL)

Storage/Transport Temperature

CRITICAL FROZEN. Separate specimens must be submitted when multiple tests are ordered.

Unacceptable Conditions

Serum. EDTA plasma, clotted or hemolyzed specimens.

Remarks
Stability

Ambient: 4 hours; Refrigerated: Unacceptable; Frozen: at -20°C: 3 months; Frozen at -70°C: 6 months

Reference Interval

Age Reference Interval
0-6 years 51-215%
7-9 years 52-176%
10-11 years 60-195%
12-13 years 50-184%
14-15 years 50-203%
16-17 years 49-204%
18 years and older 51-215%

Interpretive Data



Compliance Category

FDA

Note

Hotline History

N/A

CPT Codes

85245

Components

Component Test Code* Component Chart Name LOINC
0030250 von Willebrand Factor, Activity (RCF) 6014-5
* 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

  • RCF
  • Ristocetin Cofactor, Plasma
  • von Willebrand Factor (vWF) Activity
  • VWF:Rco
von Willebrand Factor Activity (Ristocetin Cofactor)