Megakaryocyte number and volume in megakaryocyte disorders

Bone marrow analysis was performed in normal subjects and patients with a variety of hematological conditions: hypoplastic bone marrow states (Hypo), B12 deficiency (B12 def), congestive splenomegaly (Congest), immune thrombocytopenia (ITP), chronic inflammation (Inflam), and essential thrombocythemia (ET). Left panel: The number of megakaryocytes was reduced below normal only in hypoplastic bone marrow states and was variably increased in all other conditions examined. Right panel: Megakaryocyte volume was reduced below normal only in B12 deficiency and chronic inflammation, and was variably elevated in all other conditions.