全身疾患に伴う小腸病変の臨床像と画像所見

Clinical Features and Imaging Findings of Small Intestinal Lesions Associated with Systemic Diseases

要旨●近年，内視鏡機器の進歩により小腸疾患に対する診断と治療は飛躍的に進歩した．全身疾患に伴う小腸病変は多岐にわたるが，ここでは全身性エリテマトーデス（SLE），全身性強皮症（SSc），アミロイドーシスの臨床像と画像所見について述べた．SLEの腸管病変は漿膜下の浮腫性変化および虚血に伴う潰瘍病変が主体である．SScは内輪筋の緊張低下により腸管短軸方向に管腔が著明に拡張するため，輪状ひだの間隔が狭小化しひだが密に配列し，腸粘膜が浮腫状となるが，びらん・潰瘍などの変化は通常認めない．アミロイドーシスはアミロイドが粘膜固有層に沈着し，微細顆粒状粘膜と表現される絨毛の大小不同を反映した粗糙粘膜，顆粒状ないし結節状隆起，および粘膜の脆弱性が特徴的である．

　Recent advances in endoscopic technology have dramatically improved the diagnosis and treatment of small bowel diseases. Small intestinal lesions accompanying systemic diseases are varied. In this study, we have described the clinical manifestations and imaging findings of lesions associated with Systemic Lupus Erythematosus（SLE）, Systemic Sclerosis（SSc）, and Amyloidosis SLE is characterized by subserosal edematous changes and ischemic ulcerations in the intestine. SSc is characterized by marked luminal dilatation in the short axis, resulting from reduced muscle tone of the inner circular muscle layer, which leads to the narrowing of the space between circular folds（closely packed folds）and mucosal edema. Erosions and ulcers are typically absent in SSc. Amyloidosis is characterized by amyloid deposition in the lamina propria mucosae, resulting in a “fine granular mucosa” that reflects the disparity in villous size, coarse mucosa, granular or nodular elevations, and mucosal vulnerability.