縦走潰瘍を伴ったcollagenous colitisの1例

Collagenous Colitis Accompanying Longitudinal Ulcers, Report of a Case

要旨　患者は50代の女性．水様性下痢の精査のため全大腸内視鏡検査を施行した．初回の検査では全大腸にわたり，血管透見の不良，不整所見を認め，S状結腸には細長い縦走潰瘍を認めた．生検を施行し，collagenous colitisと診断した．内服中のランソプラゾールを中止したところ，下痢は改善した．初回診断の1か月後には，縦走潰瘍は瘢痕化し，血管透見の不良，不整所見も改善傾向を認めた．病理組織学的にも経過観察中にcollagen bandが消失した．一般にcollagenous colitisは内視鏡所見に乏しい疾患とされるが，細長い縦走潰瘍病変を大腸粘膜に認めた場合，collagenous colitisの可能性を念頭に置くべきである．

　A woman in her fifties underwent colonoscopy and biopsy for investigation of chronic, non-bloody diarrhea. She had been receiving various medications including lansoplazole for about 4 months, but she had no history of receiving non-steroidal anti-inflammatory drugs. Colonoscopy revealed shallow, narrow and longitudinal ulcers located in the sigmoid colon without accompanying surrounding edema. Diminished vascular transparency and a distortion in the mucosal vascular pattern were noted on the entire colonic mucosa. Histopathological assessment of the mucosal biopsy specimens showed abnormalities consistent with collagenous colitis（CC）. After suspending lansoplazole, her diarrhea improved gradually, although no causal relationship between the onset of CC and lansoplazole was determined. After one year, the longitudinal ulcerative lesion healed to be a scarring, and the diminished vascular transparency and the distortion of the mucosal vasculature disappeared. Histologically, the collagen band was no longer seen.

　When colonoscopy shows characteristic mucosal tears, suggesting shallow ulcerative lesions of a narrow longitudinal shape, the presence of underlying CC can be considered.