経過を観察しえた腸管出血性大腸菌（EHEC）O157：H7による大腸炎の1例

Escherichia Coli O 157: H7-associated Colitis-Observation of Colonoscopic and Radiographic Course, Report of a Case

要旨　腸管出血性大腸菌（EHEC）O157：H7による大腸炎のX線・内視鏡による経過観察例を報告した．患者は，48歳，主婦.腹痛・血性下痢を主訴として，入院した，第5病日の内視鏡検査では，直腸・S状結腸の病変は軽度であったが，下行結腸～盲腸には発赤粘膜の浮腫，潰瘍・びらん形成，出血などの高度の炎症所見を認め，同日の注腸X線検査でも下行結腸～盲腸にかけて管腔の痙攣性狭細化，thumbprinting様所見を認めた．糞便検査でEHEC O157：H7が証明された．第21病日の内視鏡検査では，横行結腸に数条の縦走潰瘍瘢痕と下行結腸に発赤斑を残すのみとなりほぼ治癒した．注腸X線検査でも横行結腸に縦走潰瘍瘢痕が証明された．

　A 48-year-old female had visited our hospital on Aug. 9, 1996, because of abdominal pain and diarrhea with slight fever from the previous day. She was admitted during the night on the same day because the pain increased and bloody stool subsequently developed. Using methods of RPLA and PCR, stool test was positive for enterohemorrhagic escherichia coli O 157: H7. Radiographic picture on the 5th day after onset showed thumbprinting, irregular margin of the lumen and coarse mucosa in the transverse and descending colon. Decrease in distensibility and thickened mucosal folds in the ascending colon and cecum were also present. The findings closely resembled ischemic colitis. Colonoscopy also revealed markedly edematous and hyperemic mucosa with white coating and hemorrhages in the right and descending colon although the findings in the sigmoid colon and rectum were slight. Radiographic picture on the 21st day after onset showed longitudinal ulcer scars in the transverse colon. Colonoscopy revealed longitudinal ulcer scars and mucosal erythema in the transverse and descending colon. It was suspected that the formation of the longitudinal ulcer scars was caused by ischemia. The pathogenetic mechanism of ischemia is unknown at present.