V is for Von Willebrand’s Disease
Von Willebrand’s Disease (vWD) is another disease that is usually inherited from parents, although can also come from a spontaneous mutation. It is a defect in the clotting cascade in which the Von Willebrand factor is either missing completely or mutated so that it does not function properly. The end result of this mutation is that the individual affected is unable to clot properly and has excessive or inappropriate bleeding. In the United States it is estimated that 1% of the population (1 in every 100 people) has vWD, many go undiagnosed or misdiagnosed for an extended period of time.
There are many types of vWD:
- Type 1 is the most common, also the mildest form, is when there are just low levels of the von Willebrand factor (vWF), there may or may not also be a decrease in factor VIII levels (hemophilia is when factor VIII levels are low or absent and vWF levels are normal).
- Type 2 is actually a grouping of four subtypes 2A, 2B, 2M, and 2N in which there are normal amounts of vWF, but it does not function properly. Each subtype has a different mutation, therefore treatment for each subtype is also different.
- Type 3, the most severe form, there is low to no production of vWF and there are low levels of factor VIII.
- Frequent nosebleeds – start spontaneously, 5 or more in a year, require medical attention to stop, and/or take more than 10 minutes to stop
- Bruising – frequent (1-4+ times per month), little to no trauma, is elevated and larger than an American quarter
- Women may have heavy bleeding with menstruation that includes large clots
- Prolonged bleeding after injury, surgery, childbirth, or dental work
- Less frequently, one may also have blood in stool, urine, or joints and internal organs (severe cases)
Treatments can include:
- Desmopressin tablets or nasal spray
- Replacement therapy of missing factors
- Antibrinolytic medications
- Birth control pills for women to decrease blood loss
In veterinary medicine, we do see vWD cases as well. According to the University of Cornell School of Veterinary Medicine, vWD is most common in the Doberman Pinscher, Pembroke Welsh Corgi, Airedale Terrier, Scottish Terrier, and Shetland Sheepdog, although it is found in over 50 breeds of dogs. To lesser degrees it can also be found in pigs, rabbits, cats, and horses. Dobermans are the one that I have seen most frequently, to the point that prior to any major surgery I often recommend vWD testing for them, especially if there is a known history of it in family lines or if there is no history available. When obtaining a dog, especially when purchasing, it is important to ask about family history, specifically any known diseases or conditions, including vWD.
According to Veterinary Partner the most common breeds for each type are as follows:
- Type 1: Doberman Pinscher, Shetland Sheepdog, German Shepherd Dog, and Standard Poodle
- Type 2: German Short-haired and German Wire-haired Pointers.
- Type 3: Scottish Terriers, Chesapeake Bay Retrievers, and Shetland Sheepdogs.
If you do have a dog (or other species) with vWD, it is not recommended to breed them and they should be spayed or neutered. That being said, when it comes time for surgery, ideally, plans should be made ahead of time for medications to be on hand in case of hemorrhage.