Hemophilia in Dogs

Hemophilia common severe inherited coagulation disorder in animals and human beings. In dogs, as in other species, the disease arises as the result of spontaneous mutation. Once hemophilia appears in a family, the defect can then be transmitted through many generations.

Hemophilia A

Hemophilia A is the most common of the inherited blood clotting disorders in dogs. It is the result of a mutation of a specific gene, causing a deficiency of blood clotting Factor VIII.

The disease arises from a spontaneous mutation in the factor VIII gene which lies on the X-chromosome. Due to the X-linked recessive mode of inheritance, males are usually affected (by maternal transmission), while females are asymptomatic carriers. The birth of affected female progeny requires the mating of an affected male to a carrier female, a possibility in closely inbred families or mildly affected male hemophiliacs.

Hemophilia B

Hemophilia B (Factor IX deficiency) is less common than hemophilia A. It has been reported in several breeds of purebred dogs and a mixed-breed dog. Females are usually carriers and rarely have signs of the disease. Signs are similar to those of hemophilia A. Animals with extremely low Factor IX activity (less than 1% of normal) usually die at birth or shortly thereafter. Animals with 5 to 10% of normal Factor IX activity may suddenly develop blood clots, bleeding in the joints, oozing of blood in the body cavity, or organ bleeding

Causes of Hemophilia in Dogs

The bleeding tendency of Hemophilia A is caused by specific deficiency of a single clotting factor, Factor VIII. The clotting factors are designated by roman numeral and Factor VIII (factor eight) is critical for normal blood clot formation. Abnormalities, or mutations, in the Factor VIII gene prevent the body’s production of a normal, functional coagulation Factor VIII.

Symptoms of Hemophilia in Dogs

This disease is typically diagnosed in puppies or young adults when they are spayed or neutered and have a problem with clotting. However, it can be diagnosed at any age.

Affected puppies may bleed abnormally when teething. You may notice extensive bruising or bleeding that does not stop following a traumatic event. If spontaneous bleeding occurs, you may notice that your dog has swollen joints, difficulty breathing, and/or a pendulous abdomen.

Treatment of Hemophilia in Dogs

There is no cure for hemophilia. The main method of treatment for bleeding episodes in dogs involves repeated substitution therapy. This means intravenous whole blood or plasma transfusions until the bleeding can be controlled. Whole blood transfusions are generally given to more severe cases involving life-threatening anemia. Your dog may also be given blood products containing clotting factors. Gene therapy that uses adeno-associated viral vectors may also be a possible treatment