Clostridium difficile腸炎治癒後に典型的潰瘍性大腸炎に進展した3例

Progression to Typical Ulcerative Colitis Following Healing of Clostridium Difficile（Cd）Colitis in Three Patients

要旨　3例の主訴は下痢，血便であり，いずれも下部内視鏡検査にて非連続性のびらんがみられ，感染性腸炎を疑った．便培養でCd（Clostridium difficile）あるいはCd toxinが検出され，Cd腸炎と診断した．いずれもバンコマイシン内服投与にて症状は消失したが，それぞれ約2週後，約2か月後，約1年後に症状が再発し，内視鏡検査にて典型的潰瘍性大腸炎に進展していた．初回の内視鏡像は非連続性病変であるが，その後の経過や初回生検組織像から，Cd腸炎よりも潰瘍性大腸炎の初期病変を見ていた可能性が高いと考えられた．すなわち，Cd腸炎が潰瘍性大腸炎を誘発した可能性よりも，症状のない潰瘍性大腸炎をCdが顕在化させた可能性が高いと考えられた．

　Three patients with chief complaints of diarrhea and melena were each found, on colonoscopy, to have discontinuous erosions, and infectious colitis was suspected. Cd or Cd toxin was detected on stool culture, and Cd colitis was diagnosed. Although the signs and symptoms disappeared with administration of oral vancomycin in each patient, they recurred about two weeks, two months, or one year later, and endoscopy revealed progression to typical ulcerative colitis. Although the initial endoscopic finding was discontinuous erosions, this was considered likely to have been the initial lesion of ulcerative colitis rather than Cd colitis. In addition, asymptomatic ulcerative colitis induced by Cd was considered much more likely to be the correct diagnosis than ulcerative colitis induced by Cd colitis.