انگل، قارچ و حشره شناسی  علوم پزشکی اراک

B. coli usually lives as a non-pathogenic commensal in the large intestine and produces no symptoms. Superficial inflammation of the colonic mucosa may occur which can result in diarrhea and colicky pain. Mild or chronic infections are characterized by intermittent diarrhea and constipation, weight loss, and abdominal pain. On rare occasions the trophozoites will invade the intestinal epithelium and produce ulceration. Clinically this results in an acute diarrhea with mucus and blood (ie, dysentery). This balantidial dysentery is similar to the dysentery produced by Entameoba histolytica (see below). Rare extra-intestinal infections involving lungs, vagina, ureter and urinary bladder and intestinal perforations leading to peritonitis have been reported

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