Test Directory
| Test Code | |||||||||||||
| 8AG | |||||||||||||
| Test Name | |||||||||||||
| von Willebrand Factor Antigen | |||||||||||||
| CPT Codes | |||||||||||||
| 85246 | |||||||||||||
| Expected Turnaround Time | |||||||||||||
| 2 - 4 days | |||||||||||||
| Clinical Utility | |||||||||||||
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A decreased level of vWFAg is an indication of von Willebrand disease, an elevated level could be observed in endothelial cell activation. |
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| Specimen and Container Info | |||||||||||||
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Specimen Type: Plasma Collection Container: 1 Full Light Blue Top (Sodium Citrate) |
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| Collection Instructions | |||||||||||||
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Blood should be collected in a blue-top tube containing 3.2% buffered sodium citrate. Evacuated collection tubes must be filled to completion to ensure a proper blood-to-anticoagulant ratio. |
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| Processing and Submission Instructions | |||||||||||||
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Create platelet poor plasma according to the Specimen Collection and Processing Guidelines for Coagulation Testing. |
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| Patient Preparation | |||||||||||||
| Testing is contradictory for patients on anticoagulant therapy. | |||||||||||||
| Transport Instructions | |||||||||||||
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Transport to the laboratory frozen. |
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| Stability Requirements | |||||||||||||
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| Causes for Rejection | |||||||||||||
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| Methodology | |||||||||||||
| Immuno Turbidometric | |||||||||||||
| Reference Intervals | |||||||||||||
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| Performing Location | |||||||||||||
| Roble Road Core Laboratory | |||||||||||||
| Alternate Names | |||||||||||||
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| Testing Schedule | |||||||||||||
| Routine, 3 times per week | |||||||||||||
The American Medical Association (AMA) Current Procedural Terminology (CPT) codes published by HNL Lab Medicine are guidelines and are intended for informational purposes only. CPT coding is the exclusive responsibility of the billing entity. View the Terms.
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