Abnormalities of Platelet Function in the Myeloproliferative Disorders

Despite extensive investigation of all aspects of the coagulation system, the mechanisms underlying the hemorrhagic and thrombotic complications seen in the “myeloproliferative disorders” have not been satisfactorily elucidated. In an attempt to define the abnormality underlying the hemorrhagic diathesis, the platelet function of 21 consecutive patients admitted to the University of Minnesota Hospitals with various myeloproliferative disorders (polycythemia vera, myelogenous leukemia, agnogenic myeloid metaplasia, and erythroleukemia) was evaluated by the use of both the older, less sensitive methods, and those more sensitive and reliable techniques which have recently become available. All 21 patients demonstrated some degree of platelet function abnormality, which was more severe in those patients with clinically apparent bleeding diatheses. Two illustrative cases point out the therapeutic approaches which are currently available to control the hemorrhagic problems occurring in these patients as a consequence of their abnormal platelet functions.