小腸疾患の分類と病理診断

Classification and Histopathological Diagnosis of Diseases of the Small Intestine

要旨●小腸においても奇形・先天異常，炎症性疾患，腫瘍（上皮性，非上皮性），腫瘍様病変など種々の疾患が存在するが，小腸病変自体の頻度が比較的低い．特にまれな疾患では鑑別診断がしばしば困難である．小腸疾患の診断においては，まずは疾患の病理学的分類を理解し，それぞれの疾患の病態と組織学的特徴，および生検の有用性を知っておく必要がある．本稿では，小腸疾患の基礎的知識に加えて，重要な疾患やまれな疾患について病理学的特徴を中心に概説する．

　There are various diseases of the small intestine, such as malformation, inflammatory diseases, tumors(epithelial and non-epithelial), and tumor-like lesions ; however, the occurrence of lesions in the small intestine is relatively infrequent. Further, the differential diagnosis of rare diseases is often difficult. In the diagnosis of small bowel diseases, it is necessary to understand the pathological classification to know the histopathological features, and the usefulness of biopsy for differential diagnosis.

　In this report, in addition to the basic knowledge about small bowel diseases, we outline the histopathological features of important and rare diseases of the small intestine.