Abstract
Crohn's disease in a pair of monozygotic male twins is reported. At the age of 11, the younger brother noticed abdominal pain, diarrhea and weight loss in April 2006. Multiple ulcerations from the ileocecum to the transverse colon and duodenal stenosis were found with endoscopic examinations. At 12 years of age, the elder brother also noticed diarrhea and weight loss in June 2008. Multiple aphtha from the descending colon to the rectum and duodenal tandem erosions were found with endoscopic examinations. Both were diagnosed as having Crohn's disease because a biopsy of the large intestine revealed epitheloid granuloma. The duodenal stenosis in the younger brother did not respond to a variety of conservative treatments and gastrojejunal anastomosis was undertaken in December 2007. Postoperatively, he returned to normal school life. The elder brother responded to 5-ASA and is now in remission. In Western countries, many familial occurrence of Crohn's disease have been observed and also numerous monozygotic cases have been found. Familial and twin onset strongly supported genetic factors in the pathogenesis of Crohn's disease. In Japan, only two cases of Crohn's disease in monozygotic twins have been reported previously.
