filiform polyposisを合併し高度な狭窄症状を呈した潰瘍性大腸炎の1例

Filiform Polyposis : Inflammatory Polyposis in Ulcerative Colitis, Report of Rare Case

要旨　患者は35歳の男性．1995年発症の全大腸炎型潰瘍性大腸炎患者．経過中過去2回，大量ステロイド投与を必要とする重症再燃を経験．1999年11月ごろより再度症状の悪化を認め，2000年1月当科紹介入院となった．注腸造影および大腸内視鏡検査にて，脾彎曲部に限局し高度な閉塞所見を呈する特異な形態の炎症性ポリポーシスの集積を伴う活動期潰瘍性大腸炎と診断．白血球吸着除去療法を中心に治療，改善傾向を認めるも脾彎曲部の病変に変化は認めなかった．その後，ステロイド投与にても変化せず，内科的治療の限界と考え，大腸全摘術が施行された．摘出標本の肉眼的，病理学的検索から，潰瘍性大腸炎に合併したfiliform polyposisと診断した．

　Inflammatory polyposis is a frequent sequela of ulcerative colitis, but filiform polyposis (FP) is a rare form of inflammatory polyposis which complicates inflammatory bowel disease. FP is characterized by the presence of numerous, densely packed, filiform polyps in the colon, which may mimic villous adenoma or adenocarcinoma in its radiographic and endoscopic picture.

　We report a patient of massive polyposis forming a labyrinthian structure occurring at the splenic flexure in a 35-year-old Japanese man with a 5-year history of ulcerative colitis, in whom total proctocolectomy and ileostomy was performed because of obstruction by stricture formation and hemorrhage in spite of medication. Pathological findings revealed that the polyposis was characterized by long, finger-like inflammatory polyps which had a central core of submucosa, containing vessels and smooth muscle fibers, infiltrated by chronic inflammatory cells without neoplastic change. Judging by macroscopic and microscopic findings we concluded this patient to be a rare case of ulcerative colitis accompanied with FP. We also review the literature regarding FP.