RESUMO
Since 1931, sporadic reports have appeared noting an apparent association between hyperthyroidism and idiopathic thrombocytopenic purpura. Recent various studies suggested that these two diseases may share a similar immunologic background, but the exact mechanism is still a matter of speculation. This 22-year-old female patient visited this hospital because of general weakness and purpura of legs for 2 months. The laboratory findings were compatible with Graves' disease associated with idiopathic thrombocytopenic purpura. The platelet count was 16000/mm³, hemoglobin was 10.9 g/dl and MCV was 60.1fL. T3 was 490.53 ng/dL, T4 was 24 ug/dL and free T4 was 5.66 ng/dL. Antiplatelet antibody and antimicrosomal antibody were positive. The bone marrow findings were compatible with iron deficiency anemia and idiopathic thrombocytopenic purpura. The thyroid biopsy showed adenomatous goiter. She was administered with propylthiouracil, Beta-blocker, iron and prednisolon. On the 10th hospital day, platelet count was 184000/mm³, hemoglobin was 12.0 gm/dL and MCV was 67.5 fL. On the 20th hospital day, T4 was 10.35 ug/dL and free T4 was 2.30 ng/dL. Therefore she was discharged and followed up.