What is thrombasthenic thrombopathia?
Thrombopathia means a disorder of small blood cells called platelets or thrombocytes. Platelets play an important role at several stages of the body's response to any injury that causes bleeding. One function of platelets is to aggregate or "clump" at the site of blood vessel injury to form an initial plug. Platelets also facilitate blood clotting, in conjunction with the clotting factors, and release substances active in inflammation and tissue repair.
In thrombasthenic thrombopathia, there is a reduction or absence of certain platelet membrane proteins that are necessary for normal platelet function.
How is thrombasthenic thrombopathia inherited?
This is an autosomal trait.
What breeds are affected by thrombasthenic thrombopathia?
This disorder occurs in otterhounds. Good breeding practices have greatly reduced the disorder in this breed.
For many breeds and many disorders, the studies to determine the mode of inheritance or the frequency in the breed have not been carried out, or are inconclusive. We have only listed breeds for which there is a consensus among those investigating in this field and among veterinary practitioners, that the condition is significant in this breed.
What does thrombasthenic thrombopathia mean to your dog & you?
Some dogs have only a mild bleeding tendency which is fairly easily controlled. With dogs who are prone to more severe bleeding, owners will need to be particularly attentive to catch small injuries and attend to them, and seek veterinary attention if necessary.
In affected dogs, it is best to consult your veterinarian before using any over-the-counter medications. For example, drugs such as aspirin alter the function of platelets, and should be avoided in dogs with bleeding disorders.
How is thrombasthenic thrombopathia diagnosed?
Generally these dogs are brought to the veterinarian at a young age when the owner notices unusual bleeding. This can be in the form of nose bleeds, blood in the urine or stool, or small hemorrhages or bruising in the skin, ears, mouth or retina of the eye. There may also be prolonged bleeding in response to a small injury. Where the bleeding tendency is mild, the condition may only be suspected when your dog first undergoes surgery.
Your veterinarian will do blood tests to determine the cause of the abnormal bleeding. With this condition, platelet numbers are normal to reduced, and tests that measure platelet function will have abnormal results.
FOR THE VETERINARIAN:
Mucosal bleeding time is prolonged and there is abnormal platelet aggregation and retraction. Platelet numbers are normal to decreased and there are often giant platelets.
How is thrombasthenic thrombopathia treated?
Platelet transfusions can be given if necessary.
Affected and carrier dogs should not be used for breeding. This trait has been largely eliminated from the otterhound population through selective breeding.
FOR MORE INFORMATION ABOUT THIS DISORDER, PLEASE SEE YOUR VETERINARIAN.
de Gopegui, R.R. and Feldman, B.F. 1998 Aquired and inherited platelet dysfunction in small animals Compendium on Continuing Education for the Practicing Veterinarian. 20:1039-1052.
Copyright © 1998 Canine Inherited Disorders Database. All rights reserved.
Revised: October 30, 2001.This database is funded jointly by the Animal Welfare Unit at the Atlantic Veterinary College, University of Prince Edward Island, and the Canadian Veterinary Medical Association.