Hereditary Thrombocytopenia with an Intrinsic Platelet Defect

Thrombocytopenia, inherited as a dominant trait, was present in three generations of a kindred. The clinical picture was quite similar to that of idiopathic thrombocytopenic purpura, but thrombokinetic studies clearly distinguished the two diseases. Platelet-survival studies after labeling with 51Cr demonstrated shortened life-spans of the patients' platelets both in themselves and in normal volunteers. Platelets from healthy volunteers, however, survived normally in the patients, showing that the accelerated platelet destruction resulted from an intrinsic platelet defect and not one extrinsic to the cell. Morphologic and biochemical studies have not as yet elucidated the nature of the defect. Splenectomy in two patients was followed by improvement in the thrombocytopenia, but the postoperative platelet survival remained short.