Thrombotic thrombocytopenic purpura and haemolytic uraemic syndrome in three siblings.

Two brothers and one sister had three variants of thrombotic thrombocytopenic purpura and haemolytic uraemic syndrome (the 'TTP-HUS' complex). The sister had a chronic fatal variant of thrombotic thrombocytopenic purpura with severe neurological manifestation. One brother had a chronic relapsing disease but the kidneys were not affected, and the other brother had haemolytic uraemic syndrome. This occurrence in one family supports the hypothesis that haemolytic uraemic syndrome and thrombotic thrombocytopenic purpura are actually two variants of the same disease.