甲状腺機能異常症に合併した脛骨前粘液水腫の2例

・当科で経験した脛骨前粘液水腫（pretibia-lmyxedema，以下PTM）の2例のうち，1例はBasedow病，1例は橋本病患者であった．

・PTMはBasedow病のまれな合併症であるが,橋本病にも極めてまれに合併する．

・PTMにはTSH受容体抗体の関連が示唆されており，当科で経験した2例でも抗体価が上昇していた．

（「症例のポイント」より）

　

Pretibial myxedema associated with thyroid abnormalities : of two case reports

　

Takazawa, Maya1）Umemoto, Naoka1）Yamada, Tomoko1）Kawase, Masaaki1）Demitsu Toshio1） 1）Department of Dermatology, Jichi Medical University Saitama Medical Center

　

Two reports presents a rare case of pretibial myxedema(PTM)occurring in a 70-year-old man with Basedow’s disease and a very rare case of PTM occurring in a 60-year-old man with Hashimoto's disease. Histopathological findings confirmed the presence of PTM in two patients who underwent pretibial skin biopsy. Laboratory tests of both cases showed normal thyroid stimulating hormone (TSH)and serum free T3 and T4 levels. The TSH receptor antibody titer was elevated. The mechanism of PTM is unknown,but most likely that is increase of the score of TSH receptor antibody. Both cases responded well to topical steroid treatment.