Evaluation of topical n-acetylcysteine in diversion colitis

introduction: diversion colitis (dc) is a benign condition characterized by the appearance of inflammation in the mucosa of the colon or rectum devoid of fecal stream. oxidative stress has been associated with the etiopathogenesis of the disease. n-acetylcysteine (nac) is a substance with antioxidant properties, used in different treatments of inflammatory diseases. the purpose of this study was to evaluate the effects of topical applications of nac in an experimental model of dc. methods: thirty-six wistar rats were submitted to deviation of fecal stream by proximal colostomy and a distal mucosal fistula. they were distributed into 3 experimental groups of 12 animals according to the daily application of enemas containing 0.9% saline or 2 doses of nac, 25 mg/kg and 100 mg/kg, respectively. in each group, half of the animals were sacrificed after two weeks of irrigation and half after four weeks of irrigation. the diagnosis of colitis was assessed by histopathological analysis and the grade of inflammation by inflammatory grading scale. the results were evaluated with the mann-whitney test, adopting significance level of 5% (p<0.05). results: daily enema of nac improved the inflammatory alterations in colon without fecal stream. in colonic segments without fecal stream, the inflammatory score was significantly lower in the animals treated with 100mg/kg, compared with those treated with saline solution or 25 mg/kg of nac, regardless of the duration of intervention (p<0.05). the inflammatory score in colon segments without fecal stream was significantly lower in the animals treated with both concentration of nac, compared with those treated with saline, regardless of the concentration and duration of irrigation (p<0.01). conclusions: enemas containing nac improve the inflammatory process and constitute a beneficial tool in the treatment of dc.