Canine Thrombocytopenia

Fifty percent of Cavalier King Charles spaniels suffer from inherited thrombocytopenia.
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Blood platelets, originating in your dog's bone marrow, circulate throughout his body, repairing damaged blood vessels and allowing blood to clot. If your dog suffers from thrombocytopenia, he doesn't have sufficient numbers of blood platelets to do the job. In canines, the most common type of thrombocytopenia results from immune disorders, but the condition also occurs because of cancer, infection, drug reactions and kidney disease.

Affected Breeds

Any dog can suffer from thrombocytopenia, but half of Cavalier King Charles spaniels inherit a form of the disease known as hereditary macrothrombocytopenia, according to The Merck Veterinary Manual. Other breeds often diagnosed with the condition include all sizes of poodles, German shepherds, Old English sheepdogs and cocker spaniels. Female dogs are far more susceptible to thrombocytopenia than males.


Thrombocytopenia symptoms might be subtle or obvious, depending on the severity of the condition. If your dog is mildly affected, you might notice tiny bruises on his mucous members, including inside his mouth and the whites of his eyes. More seriously affected dogs can suffer from nosebleeds or urinary tract bleeding. Other symptoms include fever, lethargy, appetite loss, constant coughing and outright collapse. If an affected dog suffers an injury, he might hemorrhage.


Your vet takes a blood sample from your dog to determine the number of platelets. In healthy dogs, platelet counts number 200,000 per blood microliter or more. Counts for dogs with thrombocytopenia might drop below 20,000. In addition to a thorough physical examination, the vet also reviews your dog's history, including vaccinations, prescription and over-the-counter medications and any blood transfusions. Additional tests might be necessary, including that of the bone marrow, to definitively diagnosis the low platelet count cause.


Dogs with thrombocytopenia must lead quiet, stress-free lives while recuperating. Your vet might prescribe steroids at high doses initially, lowering the dosage as the dog's platelet levels rise. She might also prescribe additional immunosuppressant medications. Severely affected dogs require blood transfusions. Fortunately, with treatment, most dogs survive thrombocytopenia.