Thrombocytopenia

DEFINITION
Platelet count below the lower limit of the reference range
Purdue University Teaching Hospital reference range—200,000–900,000/mL, dogs; 300,000–700,000/mL, cats

PATHOPHYSIOLOGY
Platelets are produced by megakaryocytes in the bone marrow, released into bloodstream, and circulate for a few to several days.
In the normal state, the platelet count remains stable, because production of platelets is equivalent to the removal of platelets from the circulation and the spleen holds a fairly large reserve.
Caused by decreased production, sequestration, increased destruction, or increased use of platelets.