ダブルバルーン小腸内視鏡検査が診断に有用であった小腸動静脈奇形の1例

Arteriovenous Malformation of the Small Intestine Diagnosed by Double-balloon Enteroscopy, Report of a Case

要旨　症例は77歳，男性．繰り返すタール便と貧血を主訴に当科紹介入院となった．前医における上部・下部消化管内視鏡検査にて出血源を認めず，出血源は小腸にあると考えられた．ダブルバルーン小腸内視鏡検査を施行したところ，回腸に10mm程度の粘膜下腫瘍様隆起を認めた．隆起表面は発赤調粘膜に覆われており小潰瘍を伴っていた．その他の部位に局在病変を認めず前述の病変が出血源であると考え，病変部を含む小腸部分切除術を行った．病理組織学的には回腸壁全層に拡張した動静脈を認め動静脈奇形と診断された．原因不明の消化管出血に対しては小腸出血性病変の存在を念頭に置き，積極的に小腸内視鏡検査を施行するべきであると考えられた．

　A 77-year-old man was admitted to our hospital because of recurrent tarry stool and anemia. The bleeding source was able to be detected neither by gastroscopy nor colonoscopy. Double-balloon enteroscopy was carried out using the oral approach and additionally by the anal approach. An elevated lesion like a submucosal tumor was located in the ileum. The lesion had a reddish surface with a small ulcer. As no other lesion was observed in the small intestine, the lesion was considered to be the bleeding source. The patient then underwent laparotomy and a partial small-bowel resection was carried out. The pathological findings showed dilated veins and arteries distributed throughout all layers of the ileal wall, accompanied by a healed ulcer. Transition from artery to vein was demonstrated by elastic tissue stain. The feature was compatible with arteriovenous malformation. Double-balloon enteroscopy seems useful for diagnosis in patients with obscure gastrointestinal bleeding.