von Willebrand Factor (vWF) concentration
von Willebrand Factor (vWF) concentration test, often referred to as vWF measures the level of von Willebrand factor in blood to evaluate bleeding risk in animals. von Willebrand factor is a critical protein involved in blood clotting, helping platelets adhere to blood vessel walls during injury. This test is particularly important for diagnosing von Willebrand disease (vWD), a common inherited bleeding disorder in dogs, especially in breeds with a predisposition to vWD, such as Doberman Pinschers, Scottish Terrier, German Shepherd, Golden Retriever, Standard Poodle etc. Reduced levels of vWF indicate an increased risk of abnormal bleeding, aiding veterinarians in diagnosing vWD and guiding management strategies, especially before surgeries or other procedures with bleeding risks.
Test name
von Willebrand Factor (vWF) concentration
Test Code
2024
Section
Clinical Pathology
Species
Canine and Feline
Specimen
2 ml Citrate Plasma
Collection Guidelines
- Collect the appropriate volume of blood till the markings provided in 3.8% citrate tube (blue-top tube)
- Centrifuge for 10-15 minutes to separate the plasma. Transfer the clear plasma into a new, leak-proof plain blue-top tube and label it as “Citrate Plasma.”
- Excessively hemolyzed samples are not suitable for this test.
- Unspun samples will not be accepted.
- Refrigerate sample at 4oC until shipment.
Turnaround time
14-21 days
Packing Instructions
Label each sample with the animal’s name and a unique identifier, using a permanent marker or a secure adhesive label. Ensure the submittal form is completed with the animal’s information and relevant medical history.
References
- Brooks, M.B., et al. “Von Willebrand Disease in Dogs: Genetic and Diagnostic Advances.” Journal of Veterinary Internal Medicine, 2021.
- Couto, C.G., & Tavares, M. “Clinical Relevance of Von Willebrand Factor Testing in Veterinary Hematology.” Veterinary Clinics of North America: Small Animal Practice, 2022.
- Shearer, R., et al. “Evaluation of vWF Concentration in Veterinary Patients with Suspected Bleeding Disorders.” Journal of Veterinary Diagnostic Investigation, 2023.
