What is thrombocytopenia?
Thrombocytopenia is a term that refers to a decrease in the number of thrombocytes (blood platelets) circulating in the blood.
What are "platelets"?
Platelets are fragments of cytoplasm of cells called megakaryocytesthat are produced in the bone marrow. Platelets are an importantfactor in the blood clotting mechanism, so thrombocytopenia can leadto spontaneous bleeding.
What causes thrombocytopenia?
Any severe or prolonged blood loss, increased internal destructionof platelets, or impaired bone marrow production can lead toshort-term (acute) or longer term (chronic) deficiency of platelets.
What diseases or conditions are associated with thrombocytopenia?
Many diseases have thrombocytopenia as one component of thecondition. For example, infections, neoplasia, immune systemdisorders, and various drug therapies such as anti-cancer treatments.
How common is thrombocytopenia?
Thrombocytopenia is quite common. For instance some surveys have shown as many as 1% of cats admitted to veterinary hospitals are platelet-deficient.
How is thrombocytopenia diagnosed?
A blood test is used to diagnose thrombocytopenia. Platelet counts of less than 20,000 to 30,000 per uL of blood make spontaneous hemorrhage likely. Additional diagnostic tests are used to investigate the underlying causes of the problem.
What treatments are used?
If the blood loss has been acute a blood transfusion may be required. Usually treatments are aimed at the underlying causes of the problem.
Can there be bleeding disorders with normal numbers of platelets?
Yes, if platelet function is impaired. This occurs with a number of drugs including some antibiotics; also there are inherited platelet defects. One of the best known is von Willebrand's Disease (see separate topic) although this disease is rare in cats. Examples of congenital platelet defects occur in Domestic Shorthair cats, and in Chediak-Higashi syndrome, a partial albinism (lightly colored iris of the eye) seen in some lines of Persians and other breeds. Diagnosis requires tests of platelet function. There are no specific treatments other than transfusions as needed.