Crohn病確定診断例にみられる非定型病変とその経過

Atypical Lesions Observed in Confirmed Cases of Crohn's Disease and Their Progression

要旨●当科で経験したCrohn病（CD）の潰瘍性大腸炎（UC）類似病変合併例の特徴について検討した．その頻度は28%と以前より高率で，IBD症例数の増加やIBDU（IBD unclassified），非定型病変に詳細な観察が行われていることなどが理由と考えられた．UC類似病変の出現部位は左側結腸に多く認められ，経過中に出現部位が変化する症例も含まれた．CDの診断では，小腸の縦走潰瘍や不整形〜類円形潰瘍，肛門病変，生検病理組織学的所見における非乾酪性類上皮細胞肉芽腫が有用であった．もう一つの非定型病変として，アフタ性病変のみからCD典型例へ進展した症例を提示した．アフタ性病変のみの症例では大腸内視鏡検査のみで終わらせず，上部消化管の検索や経過観察に加え，病変が進展する可能性と経時的な画像検査の必要性を患者に説明する必要がある．

　We examined the characteristics of patients with Crohn's disease（CD）complicated with ulcerative colitis（UC）-like lesions who were diagnosed and treated at our department. The frequency of this condition was 28%, which was higher than the previously reported frequencies. This increase in frequency may be due to an increase in the number of inflammatory bowel disease（IBD）and IBD unclassified cases and the detailed examination of atypical lesions. The common site of onset of UC-like lesions was the left colon, but it varied in some cases during the course of the disease. The histopathological findings of biopsy specimens, including longitudinal ulcers in the small intestine, irregular to round ulcers, anal lesions, and noncaseating epithelioid cell granulomas, were useful for diagnosing CD. A case of another atypical lesion that progressed from an aphthous lesion to typical CD was presented. Patients with only aphthous lesions cannot be treated with colonoscopy alone. It is necessary to explain to the patients that the lesions may advance, and follow-up imaging tests may be required in the future in addition to observing the progress of the upper gastrointestinal tract.