汎下垂体機能低下症によるflexion contractureの1例

A Case of Flexion Contracture Associated with Hypopituitarism

症例は72歳男性である。49歳でRathke囊胞に対して手術を施行され，汎下垂体機能低下症で当院通院中であった。67歳頃より徐々に歩行困難と筋硬直が出現した。下肢の伸展制限と触診で疼痛を伴う筋硬直が見られた。当初Stiff-person症候群を考えたが抗GAD抗体が陰性，ジアゼパムが無効と非典型的な点があったことから汎下垂体機能低下症によるflexion contractureを鑑別疾患に挙げた。コルチゾール補充後より症状が著明に改善した。汎下垂体機能低下症でflexion contractureが稀に出現し，ホルモン補充により著明に改善することがある。

Abstract

A 72-year-old Japanese man developed progressive disturbance in ambulation with flexion contractures 5years before this admission. At 49 years of age, he was diagnosed with hypopituitarism after an operation for a Rathke's cleft. On admission, he could not fully extend his knees and hips because of painful muscle stiffness of the lower extremities. Initially, we suspected Stiff-person syndrome and initiated diazepam, which had no effect. Serum anti-glutamic acid decarboxylase antibody was negative. Next, we suspected flexion contractures associated with hypopituitarism. Endocrine evaluation revealed that ACTH, cortisol, and other hormone levels were lower than those reported in the previous evaluation. We treated the patient with hydrocortisone and his symptoms dramatically improved. It is rare for patients with hypopituitarism to have flexion contracture. This case suggests that we should consider hypopituitararism in the setting of flexion contractures.

(Received October 18, 2018; Accepted March 26, 2019; Published June 1, 2019)