慢性関節リウマチ患者にみられた腸の潰瘍性病変

Ulcerative Enteropathy in Patients with Rheumatoid Arthritis

要旨　慢性関節リウマチ（以下，RA）患者でアミロイドーシスを伴わず大腸な

いし小腸に潰瘍性病変を認めた5例について，その形態学的特徴，成因を検討した．病変部位は，4例は大腸で左半結腸に生じ，S状結腸には4例とも病変が認められた．残り1例は小腸で終末回腸であった．潰瘍の形態は縦走潰瘍とアフタ様ないし円形潰瘍の混在で，1例を除いて多発していた．更に，潰瘍の境界は鮮鋭で，介在粘膜には明らかな異常所見は認められなかった．RAの病期，病悩期間，活動性および治療薬と潰瘍発生には，明らかな因果関係は認められなかった．成因については，小腸病変の1例は組織学的に血管炎が証明された．大腸病変の4例中1例は虚血性大腸炎に一致する組織像を呈し，残り3例では確診は得られなかったが，臨床像は虚血性の変化と多くの共通点を有していた．潰瘍の成因としては，RAに起因した血管炎などによる慢性的な末梢血管の循環不全の関与が示唆された．

　We investigated the clinical and histological features of five patients with rheumatoid arthritis, who manifested ulcerative enteropathy other than gastrointestinal amyloidosis.

　Four patients were affected in the left side of the colon, while the other in the terminal ileum. The sigmoid colon was involved in each patient with colonic involvement. Multiple ulcers were found in four patients. The ulcerative lesions, with or without aphthoid or round ulcers, had morphologically common characteristics, viz. longitudinal ulcers, sharply demarcated from the surrounding mucosa, which was normal in appearance.

　Histologically, the existence of vasculitis was confirmed in the resected terminal ileum of one patient (case 5), while the histology of one colonic lesion (case 4) was compatible with that in ischemic colitis.

　Although the etiology of colonic lesions in the remaining three patients is still obscure, we consider that these lesions may have been caused by chronic microcirculatory disturbance in the submucosal vessels around the ulcers. We say this because the clinical and morphological features of our patients had some similarities to ischemic disorders such as ischemic colitis, vasculitis (case 5) and intestinal Behçet disease.