Megakaryocytopoiesis in refractory chronic immune thrombocytopenia.

The extent of megakaryocytopoiesis (Mk-poiesis) and clinical outcome are evaluated in 14 patients with severe refractory chronic immune thrombocytopenia (rchr ITP). Three out of 14 patients died due to hemorrhage. The number of bleeding episodes and the number of treatment modalities proved to be both sensitive prognostic survival parameters (p < 0.05). Thirty two corticosteroid responsive chr ITP patients (chr ITPPR), 15 not treated patients (chr ITP(NT)) and 14 healthy volunteers (C) served as a control. There was a significant difference in the platelet count between the study groups (p < 0.05). The number of megakaryocytes and promegakaryoblasts per mm3 of bone marrow were significantly lower in rchr ITP patients (p < 0.05) than in chr ITP(PR) and in chr ITP(NT) group, thus implying an inadequate Mk-poiesis in rITP chr patients. From the data presented here it may be suggested that the inadequate Mk-poiesis is operating in rchr ITP.