7) 潰瘍性大腸炎の小腸病変

Small Bowel Involvement in Ulcerative Colitis

要旨　潰瘍性大腸炎（UC）は大腸に限局する炎症性腸疾患と定義されているため，古典的には小腸病変はみられない．しかし実際にはbackwash ileitisや術後の回腸嚢炎が知られている．最近はUC関連十二指腸炎の報告が増加している．さらに回腸囊の近位側に炎症が及ぶpre-pouchitisや，十二指腸から空腸に炎症が及ぶUC関連enteritisの報告がみられる．UC関連十二指腸炎の内視鏡的特徴は，もろい粘膜，細顆粒状粘膜，多発アフタであるが，多発アフタはCrohn病でもみられるため，詳細な鑑別診断を要する．

　Ulcerative colitis (UC) is an inflammatory bowel disease, traditionally regarded as being confined to the large intestine. However, the duodenal involvement of UC has recently been reported as well as backwash ileitis and postcolectomy pouchitis. Furthermore, more extensive involvement in the small intestine such as pre-pouchitis and UC-associated enteritis is also reported. Although the endoscopic features of the small intestine are poorly documented, those of duodenitis associated with UC are thought to be friable or granular mucosa, or multiple aphthae. To regard multiple aphthae as UC lesions, strict exclusion of other disorders such as Crohn's disease is required.