Molecular and biochemical basis for the platelet dysfunction in myeloproliferative disorders.

A large number of platelet abnormalities have been described in patients with myeloproliferative disorders (MPDs). Platelet abnormalities include defects in receptor expression on the platelet surface, platelet-platelet interactions, and platelet activation mechanisms. These platelet defects are demonstrable even in patients who are asymptomatic. Both hemorrhagic and thrombotic events occur in MPD patients. The mechanisms that underlie the platelet dysfunction in patients with MPDs are examined.