Thrombotic thrombocytopenic purpura in four siblings

Abstract A family is described in which four members of a sibship of seven have suffered from a hematologic and systemic disorder which has been fatal in three and has been proved at autopsy to have been thrombotic thrombocytopenic purpura. The fourth member has probably suffered the same disorder. The clinical, laboratory and genetic features of the family are discussed at length. No cause of the disorder has been determined.