Idiopathic thrombodytopenic purpura , also called immune-mediated thrombocytopenia, is a disease that attacks the blood platelets. It can be a primary autoimmune disease or secondary to lupus, various types of infections, or caused by certain drugs. About a third of dogs with ITP also have immune mediated hemolytic anemia. Dogs with ITP can be lethargic, anorexic and show various signs of blood clotting deficit, including bruising, nosebleeds, bleeding from mucus membranes, and bloody stools. Affected dogs can suffer serious internal hemorrhage; ITP is potentially fatal.
Dogs with ITP are very ill and will probably require emergency care and hospitalization. Perhaps the most important diagnostic step is ruling-out other possible causes – warfarin (rat poison) toxicity, hemangiosarcoma, other blood-clotting disorders, effects of chemotherapy, etc. – to make sure the most effective treatment is given in a timely manner. Specific diagnosis of ITP is made with blood tests, including a platelet count and a test designed to detect platelet autoantibodies. Initial treatment is usually focused on controlling the bleeding and will be followed with drug therapy. Splenectomy may result in cure. Otherwise, long term care would require life-long medication.
Primary ITP is a type of autoimmune disease. Autoimmune diseases are genetically predisposed; if a dog has the disease, it has the genes. Dogs affected with primary ITP should not be bred. Their near relatives should not be bred to mates with a family history of any autoimmune disease.