Canine Immune Mediated Thrombocytopenia (ITP)

Canine immune mediated thrombocytopenia (ITP), is an autoimmune disease. The body's immune system is designed to fight foreign substances in the body, like germs and viruses. But in autoimmune diseases, the immune system attacks healthy tissues, not germs. In case of ITP, the immune system attacks platelets – the cells responsible for clotting the blood. When platelet levels are low, clotting is slowed and spontaneous bleeding occurs.

In mild cases, the affected dog may present with many pinpoint bruises on the gums, whites of the eyes, mucous membranes or skin. These bruises are called petechia, and they may develop into larger bruises. Dogs may also bleed into their intestinal, urinary or respiratory tracts, and nosebleeds are common. Bleeding can be severe and lead to anemia. Some dogs will also have a fever.

The diagnosis is made by finding reduced numbers of platelets in the blood stream and ruling out other causes such as some tick transmitted infectious diseases. Normal platelet counts are 200,000 or above. When these numbers are below 20,000, bleeding starts to occur. In the acute phase of the disease, blood transfusions are often necessary due to severe anemia. Treatment involves the use of corticosteroids in combination with other immunosuppressant drugs such as azathiaprine, cyclosporine or leflunomide which are usually continued for several months after remission has been achieved.

Although ITP is a life threatening disease, it can usually be treated successfully and survival rates are approximately 90%.

Published on July 23, 2010.