潰瘍性大腸炎確定診断例にみられる非典型病変とその経過—潰瘍性大腸炎関連の胃十二指腸病変および小腸病変

Atypical Lesions and Their Course in Ulcerative Colitis：Ulcerative Colitis-associated Gastroduodenal and Small Intestinal Lesions

要旨●潰瘍性大腸炎（UC）の非典型病変としてUC関連胃十二指腸病変や小腸病変が知られるが，その臨床経過については不明である．今回，大腸全摘術が施行されていない症例におけるUC関連胃十二指腸病変および小腸病変の長期的な臨床経過について検討した．胃十二指腸病変は73.7%（14/19）が内視鏡的寛解に至り，病変部位別では胃病変の75.0%（9/12），十二指腸病変の72.2%（13/18）が寛解に至った．胃十二指腸病変の60か月および120か月後の累積寛解維持率は70%であった．小腸病変症例では胃十二指腸病変の合併を71.4%（5/7）に認め，小腸病変の経過が追えた4例は全例内視鏡的寛解に至った．ステロイドや5-ASAなどに対する反応は良好で，UCの寛解が維持できれば胃十二指腸病変および小腸病変も寛解が維持されたが，診断後にUC難治のために大腸全摘術が施行されたのは，それぞれ14.3%（3/21）と28.6%（2/7）であった．対象症例の経過中にUCの診断が変更となった症例はなく，今後さらに形態学的特徴や臨床経過が明らかとなれば，inflammatory bowel disease unclassified症例における診断の補助となる可能性も示唆される．

　UC（ulcerative colitis）-associated gastroduodenal lesions and small bowel lesions are known as atypical lesions of UC ; however, their clinical course remains unknown. In this study, we examined the long-term clinical course of UC-associated gastroduodenal and small bowel lesions in patients who had not undergone total colorectal resection. In approximately 73.7%（14/19）of the patients, gastroduodenal lesions were in endoscopic remission. According to the lesion site, 75%（9/12）of the gastric lesions and 72.2%（13/18）of the duodenal lesions went into remission. After 60 and 120 months, the cumulative remission maintenance rate for gastroduodenal lesions was 70%. Gastroduodenal lesions were observed in 71.4%（5/7）of the patients with small intestinal lesions, and upon follow-up, all four patients with small intestinal lesions went into endoscopic remission. The response to steroids and 5-aminosalicylic acid was optimal, and if UC remission was maintained, the gastroduodenal and small intestinal lesions also remained in remission. Total colorectal resection was performed for refractory UC in 14.3%（3/21）of the gastroduodenal lesions and 28.6%（2/7）of the small bowel lesions. No cases were observed where the diagnosis of UC was revised during the course of the eligible cases.

　Further clarification of the morphological characteristics and clinical course may guide in the diagnosis of the unclassified cases of inflammatory bowel disease.