潰瘍性大腸炎と臨床診断され，4年後の生検でアメーバ赤痢と確診された1例

Amebic Colitis Diagnosed by Biopsy after Four Years of Treatment as Ulcerative Colitis, Report of a Case

はじめに

　近年，本邦においても潰瘍性大腸炎やCrohn病などの炎症性腸疾患が増加し多数発見されるようになってきたが，これらの疾患の鑑別疾患の1つに腸アメーバ症を常に念頭に置く必要があると考えられる.われわれは初回診察時に潰瘍性大腸炎と誤診したため再燃緩解を繰り返し，4年後の生検で偶然Entamoeba histolyticaを発見され確定診断の得られた1例を経験したので報告する．

　A 34 year-old man vislted our hospltal, complamlng of bloody dlarrhea. He had no history of being abroad. Proctoscoplcal study revealed edematous and reddish mucosa with muliple eroions in the rectum in May 1980. These findings were most suggesive of ulceraive colitis and consequently predonlsolone suppository and salazosulfapyridine were started, With these medications symptoms were relieved temporarily only to enter into the period of frequently alter-nating relapses and remissions of bloody diarrhea. Endoscopical examination performed in February 1981revealed edematous and reddish mucosa with multiple erosions through the entire colon.

　Histological findings of biopsy specimen showed diffuse inflammatory cell infiltration in colonic epithelium without goblet cell depletion and crypt abscess. Based on these findings, in the next four years he was again given the treatment directed to chronic ulcerative colitis. However, biopsy specimen taken in May 1984 demonstrated Entamoeba histolytica at last. Immediately metronidazole was administered for one week resulting in the disappearance of the lesions.

　It seems most important to take amebic colitis into consideration in the differential diagnosis of inflammatory bowel disease.