潰瘍性大腸炎とCrohn病の鑑別診断が困難であった分類困難腸炎の1例

Indeterminate Enterocolitis, Difficult to Differentiate from Ulcerative Colitis and Crohn's Disease, Report of a Case

要旨　患者は26歳，男性．18歳時より軟便傾向が持続するため1997年10月に当院を受診．注腸造影および大腸内視鏡検査で，S状結腸から盲腸まで連続するびまん性の炎症所見を認め，びらん形成を伴っていた．生検組織では，陰窩炎および一部に陰窩膿瘍を認めた．しかし終末回腸には，多発する浅い不整形潰瘍がみられ，生検組織で非乾酪性類上皮細胞肉芽腫を認めた．その後，大腸の病変部には縦走潰瘍の出現を認めたが確定診断には至らず，分類困難腸炎として経過観察中である．肉眼所見および病理組織学的にも，潰瘍性大腸炎とCrohn病の特徴を合わせ持つ，まれな症例と考え報告する．

　A 26-year-old male visited our hospital because of continuous soft stool. Barium enema and colonoscopic examinations showed multiple small ulcers and erosions with inflammatory mucosa diffused continuously from the sigmoid colon to the cecum. Histological findings of the biopsied specimens showed marked small round cells infiltrating in the mucosa and submucosa. In addition, cryptitis and crypt abscess were also seen. In the lower part of the ileum, multiple irregular-shaped shallow ulcers were seen by colonoscopic examination, and histological findings of the biopsied specimen showed epithelioid cell granulomas in the mucosa. Follow-up colonoscopic examinations showed multiple longitudinal ulcers in the colon and the ileum.

　We classify our case as indeterminate enterocolitis, because it was very difficult to differentiate it from ulcerative colitis and Crohn's disease.