Increased colonic ornithine decarboxylase activity in inflammatory bowel disease in children

The risk of colorectal carcinoma is increased in pediatric-onset inflammato ry bowel disease (IBD). There is little information available regarding the colonic mucosal proliferative state in children with IBD, The aim of this study was to assess colonic ornithine decarboxylase (ODC) activity, a marke r of cell proliferation, in pediatric IBD patients. ODC activity was assess ed in colonic mucosa from 23 children (7 with ulcerative colitis, 9 with Cr ohn's disease, and 7 controls) undergoing colonoscopic examination. ODC act ivities were then compared with degree of inflammation of biopsied samples. ODC activities in patients with and without corticosteroid treatment were also analyzed. The mucosal ODC activities of sigmoid colon and rectum were significantly higher (2.5- to 4-fold) in both ulcerative colitis and Crohn' s disease. The higher ODC activity was associated with increased mucosal in flammation. Moreover, treatment with corticosteroids decreased the ODC acti vity. In conclusion, using ODC activities as a marker of cell proliferation , our results suggest that there is a higher colonic mucosal proliferative stare in children with IBD. The increased ODC activities were associated wi th increased colonic mucosal inflammation. Colonic mucosal ODC activity may provide an additional parameter to access the therapeutic efficacy of cort icosteroid treatment in pediatric IBD patients.