2)小腸の出血性疾患

Differential Diagnosis of Hemorrhagic Small Intestinal Diseases

要旨　出血性小腸疾患は，大きく炎症性疾患，腫瘍性疾患，血管奇形などの疾患群に分類可能であるが，通常その診断過程においては血便の性状に応じて他の消化管内視鏡検査が先行して行われる．その場合，他の消化管の随伴病変が小腸疾患診断の手掛かりとなることも少なくない．また，原因疾患によっては特徴的な臨床像や病歴などを有するものも多い．さらに，その小腸画像所見は各疾患群によりある程度共通した特徴を有している．したがって，出血性小腸疾患の診断に際しては，他の消化管の随伴病変，臨床像および病歴なども加味して，各疾患の小腸病変の画像的特徴を念頭に置き，総合的に鑑別を行っていくことが必要である．

　For the diagnosis of hemorrhagic small intestinal diseases, in the first examination, upper gastrointestinal endoscopy and/or colonoscopy is usually performed before the examination of the small intestine. The endoscopic findings may give an important clue for diagnosing the diseases of the small intestine. In some of these diseases, the clinical features and carefully taken histories are often helpful for differential diagnosis. Furthermore, these hemorrhagic small intestinal diseases, which are generally classified into 3 groups (inflammatory, tumors, vascular malformations), have to some extent, common morphological features shown by the radiological and endoscopic studies of the small intestine in each group.

　In addition to the foregoing clinical aspects, it is important for the diagnosis of hemorrhagic small intestinal diseases to differentiate them bearing in mind the radiological and endoscopic features of the small intestine in each disease.