The appendix in inflammatory bowel disease in children.

The morphologic characteristics of the colon in ulcerative colitis and Crohn's disease are well established, but specific appendiceal pathology is less clearly defined. In addition, the frequency of appendiceal involvement in children with inflammatory bowel disease has also not been delineated. We have determined the prevalence of appendiceal involvement in 41 children with inflammatory bowel disease (24 with Crohn's disease and 17 with ulcerative colitis) who required colonic resection and have defined the histopathologic characteristics of the appendix in these diseases. All appendices were abnormal. Specific changes of Crohn's disease or ulcerative colitis were observed respectively in 50% and 56% of the appendices in our patient population. Nonspecific changes only such as fibrous obliteration, serosal fibrosis and lymphoid and/or neuronal hyperplasia were noted in the remaining appendices. The severity of ileocolonic and appendiceal inflammation was similar in about two thirds of the patients with either type of inflammatory bowel disease.