Platelet kinetics in autosomal dominant macrothrombocytopenia.

A family with autosomal dominant macrothrombocytopenia is described. Despite severe thrombocytopenia, only a moderate hemorrhagic tendency was observed. Kinetic studies revealed a normal platelet survival, normal megakaryocytic numbers, and normal bone marrow responsiveness. The rate of platelet production was set low, despite moderately impaired hemostasis and thrombocytopenia; it apparently was set to maintain another platelet parameter at an optimal level. Measurements of total circulating platelet mass and platelet surface suggested that the platelet production was set to maintain the platelet surface rather than the platelet mass at a normal value.