essential thrombocythemia ( et ) in an 11-year-old dog was characterized by persistently high platelet counts ( range , 4.19 x 10 ( 6 ) /microliters to 4.95 x 10 ( 6 ) /microliters , abnormal platelet morphology , marked megakaryocytic hyperplasia in the bone marrow , absence of circulating megakaryoblasts , and history of splenomegaly and gastrointestinal bleeding .
C0040028
essential thrombocythemia
C0836924
high platelet counts