区域性・非連続性病変を呈する潰瘍性大腸炎の臨床的検討

Clinical Study of Ulcerative Colitis (UC) Patients with Disease Discontinuity: For New Diagnostic Concept of UC

要旨　従来のUC診断基準の概念を再考するために，UC186例の中から非連続性病変を呈する非典型例を抽出し，これら症例の臨床的特徴を検討した．治療や経過の影響により直腸が一見正常に見えたり病変が区域性であったものは24例（12.9％）あった．右側あるいは区域性大腸炎は7例（3.8％）で，女性に多く，いずれも直腸に病変がなかった．これら症例の約70％は約3年の間に直腸に典型的なUCの炎症像を有するようになった．虫垂開口部周囲に非連続性病変を呈する症例は16例（主病変が肝彎曲部までにとどまる例の15.4％）で，男性に多かった．同病変は発赤，小びらんなどで発症早期から認められたもの10例，経過の途中から認められたもの6例であった．同病変の約63％は治療により消失し，病変が肛側に広範進展した例はなかった．発症早期に直腸に非びまん性の斑状発赤を呈し感染性腸炎との鑑別が困難な症例は4例（2.2％）あった．これらは若年発症例で，早期にUCの治療を行った2例は病変の進展が抑制されていた．以上より，右側あるいは区域性に加えて，直腸の炎症欠如，虫垂開口部病変，直腸の斑状病変など非連続性，非びまん性病変などの存在に言及した新しいUCの診断基準概念を提唱するべきであると考えられた．

　In order to reconsider the traditional diagnostic concept of ulcerative colitis (UC), UC patients with various patterns of disease discontinuity were clinically assessed.

　The presence of UC patients with various patterns of disease discontinuity was retrospectively evaluated in 186 patients with ulcerative colitis. Rectal sparing or segmental lesion due to treatment were found in 24 (12.9%) of all UC patients. Right-sided or segmental colitis was found in 7 (3.8%) of all UC patients. None of them showed rectal disease but 5 (70%)cases developed typical rectal involvement of UC within 3 years. Appendiceal orifice inflammation as a skip lesion was found in 16 (15.4%) of 104 patients with active UC that did not extend beyond the hepatic flexure. This lesion was detected at an early stage of disease development in 10 cases and detected during follow-up in 6 cases. Sixty-three percent of the lesions disappeared after UC therapy and none of them extended to the anal site of the colon. Patchy inflammation of the rectum was found in 4 (2.2%) of 186 UC patients. This lesion was detected in young patients and created a difficulty in distinguishing UC from infectious colitis. In spite of the diagnostic difficulty, two cases received SASP therapy and disease extension was prevented.

　Our data has challenged the concept of that UC is a continuous and homogeneous inflammatory process with constant rectal involvement and we recommended the mention of the above reported discontinuous lesions in the diagnostic criteria of UC.