collagenous colitisの2例―最近の知見を含めて

Collagenous Colitis: Review from Recent Literatures, Report of Two Cases

要旨　Collagenous colitisは従来まれな疾患と考えられてきたが，疾患概念の浸透とともに欧米をはじめ本邦でも報告例が散見され，決してまれではないことがわかってきた．本稿では，筆者が大腸内視鏡を施行して本疾患を疑い診断した2症例を紹介し，若干の考察を加えた．〔症例1〕は脳梗塞を発症し，救急病院入院後から下痢が出現した．大腸内視鏡は，右側結腸で新鮮なびらん・裂傷様の所見を，横行結腸からS状結腸には縦走する瘢痕を認めた．生検の組織像では，表面上皮直下で肥厚した膠原線維束が形成されており，表面上皮は変性，脱落し，形質細胞の増加が特徴的な慢性炎症細胞浸潤を認めるが，好中球浸潤は軽度であった．〔症例2〕は循環器専門病院で加療中，2か月前から3，4行/日程度の下痢が出現した．大腸内視鏡は異常所見を認めなかった．病理組織で慢性炎症細胞浸潤，特に形質細胞浸潤が深部まで認められ，好酸球も認められた．表層被蓋上皮の変性，剥離像とともに，80μmと肥厚した膠原線維束を認めた．

　Collagenous colitis was thought to be a rare disease, but, since the concept of this disease has spread widely, the number of reports on lesions thought to be collagenous colitis have increased.

　Case No.1 : The patient was treated in hospital, because of cerebral infarction. Soon after the treatment, diarrhea occurred and the symptom did not response to antidiarrheal agents. Total colonoscopy was performed and linear fresh ulcer and scars were detected. Pathological specimens revealed chronic inflammatory cell infiltration and a collagen band.

　Case No.2 : The patient was treated in hospital, because of arrhythmia. Diarrhea had occurred from two months before and the symptom did not respond to antidiarrheal agents. Total colonoscopy was performed and no abnormal finding was observed. Pathological specimens revealed chronic inflammatory cell infiltration and a collagen band.