[Primary thrombocythemia: clinical, pathophysiology and therapeutic possibilities].

The course of primary thrombocythemia has been observed in 22 patients over a period of 1-19 years. In contrast to experience with primary thrombocythemia in the literature, thrombotic complications were far more common than hemorrhage. 20 out of 22 patients complained of pain in toes and fingers due to disturbances of microcirculation, whereas bleeding disorders were present only in 5. Studies on spontaneous aggregation of platelets revealed a close association between platelet hyperaggregability and ischemic attacks. 500 mg acetylsalicylic acid every second day normalized the hyperaggregability in vitro and removed pain completely. The indication for antiaggregating substances in the therapy of primary thrombocythemia is discussed.