橋本病を合併した特発性血小板減少性紫斑病の1例

Abstract

We report a case of idiopathic thrombocytopenic purpura with Hashimoto' s thyroiditis. A 67-year-old female was admitted to our hospital for bleeding tendency in December 1992. Laboratory findings were as follows : platelet count was 3,000/mm3, PA -IgG was 605 ng/10^7 cells, megakaryocyte count in bone marrow examination was 117/μl, free T3 was 68.8 ng/dl, free T4 was 1.8 μg/dl, TSH was 395.7 μu/ml, anti-thyroglobulin antibody was ×400, and anti-microsome antibody was ×25,600. The patient was diagnosed as having idiopathic thrombocytopenic purpura (ITP) with Hashimoto's thyroiditis. Prednisolone was administered for ITP, and levothyroxine sodium for Ha- shimoto's thyroiditis. The platelet count increased. Anti-thyroglobulin antibody and anti -microsome antibody were ×400 and ×25,600 respectively in December 1992. They became depressed to under ×100 and 25,600 in January 1993, and to under ×100 and under ×100 in July 1997. This case suggests that a common immunological mechanism exists between ITP and Hashimoto's thyroiditis, and that prednisolone is effective for both thrombocytopenia due to ITP and hypothyroidism due to Hashimoto's thyroiditis.