Megakaryocytes can be found normally in blood vessels of the liver, lung and spleen.
Normal megakaryocytes or megakaryocytic fragments can be found:
(1) occasionally in blood smears from normal patients
(2) in buffy coats
(3) in the cord blood of neonates
(4) following an acute stress
(5) with a myelophthisic process involving the bone marrow
In myelodyplasia and/or myeloproliferative disorders the peripheral blood may show:
(1) abnormal platelets
(2) large cytoplasmic fragments of megakaryocytes
(3) dwarf micromegakaryocytes
(4) other types of abnormal megakaryocytes
In acute megakaryocytic leukemia (M7) dysplastic megakaryoblasts will be seen in large numbers in the peripheral blood.
