小腸潰瘍性病変の鑑別診断―びまん性疾患を中心に

Diagnosis of Ulcerative Lesions in Diffuse Small Bowel Diseases

要旨　小腸びまん性疾患における潰瘍性病変の特徴とその鑑別診断について概説した．びまん型小腸リンパ腫のうち，腸症関連T細胞リンパ腫ではKerckring皺襞の肥厚と大型の潰瘍性腫瘤，成人T細胞性白血病/リンパ腫では白色調の顆粒状粘膜と小潰瘍が特徴的である．全身性エリテマトーデスや好酸球性胃腸炎では粘膜浮腫が主体で潰瘍形成はまれだが，びらんや小潰瘍を来すことがある．Schönlein-Henoch紫斑病では十二指腸と回腸に大小の不整形潰瘍が好発する．Churg-Straus症候群では小腸全域にわたって大小の深い潰瘍を認める．移植片対宿主病は終末潰瘍に広く浅い地図状潰瘍がみられる．各疾患における潰瘍の好発部位と形態的特徴を理解して，適切なX線造影・内視鏡検査を行うことが重要である．

　The endoscopic and radiographic features of ulcerative lesions in representative diffuse small bowel diseases are reviewed. Among the diffuse small bowel lymphomas, enteropathy-associated T-cell lymphoma is characterized by diffuse thickening of the bowel folds with large ulcerative tumors, whereas adult T-cell leukemia/lymphoma tends to appear as a granular mucosa with multiple small ulcers. In patients with systemic lupus erythematosus and eosinophilic gastroenteritis, obvious ulcers are usually absent, although erosions or small ulcers are occasionally observed. In Henoch-Schönlein purpura, multiple irregularly shaped ulcers frequently occur in the duodenum and ileum, whereas in Churg-Strauss syndrome, multiple deep ulcers occur in extensive areas of the small bowel. Graft-versus-host disease predominantly involves the terminal ileum with wide, irregular, and shallow ulcers. For accurate clinical diagnosis of these diffuse small bowel diseases, it is important to understand the above morphological characteristics of the ulcerative lesions in each disease.