Veterinary Clinical Medicine-I (General and Systemic)

IMMUNE - MEDITATED  THROMBOCYTOPENIA

• Platelets in the form of platelet rich plasma, platelet concentrate, or fresh whole blood, are only transfused when the patient has severe uncontrolled or life-threatening bleeding. In fact transfused platelets given to IMT patients have a very short survival of a few minutes to hours and thus do not generally increase the blood platelet count despite providing transiently improved hemostasis.
• Beside treating the underlying disease, such as ehrlichiosis, babesiosis, and drug allergy, immunosuppressive agents are used to impair the macrophage system and production of platelet antibodies. Glucocorticoids are the first choice either in the form of prednisone at 1-2 mg/kg or dexamethasone at 0.2-0.3 mg/kg BID; the initial dose is slowly tapered after the recognition of a response by no more than one third the dose every 2 weeks. Vincristine at 0.02 mg/kg strictly IV once may accelerate the platelet count recovery by impairing the macrophage system, stimulating platelet release from the megakaryocytes and platelet production. Other immunosuppressive agents such as cyclosporine, azathioprine, and intravenous immunoglobulin may also be considered, but their efficacy and safety have not been documented. Finally, splenectomy is highly effective in corticosteroid refractory IMT in human patients, but has not been adequately evaluated in dogs