Diagnosis and management of a solitary colorectal juvenile polyp in an adult during follow-up for ulcerative colitis: A case report

BACKGROUND: Juvenile polyps are the most common type of polyps in children but are rare in adults. Inflammatory bowel disease (IBD) patients have a similar spectrum of symptoms as patients with juvenile polyps. Both patients with juvenile polyps and those with active IBD have high fecal calprotectin levels. Four cases of children with ulcerative colitis (UC) with solitary juvenile polyps and one case of an adult with UC with juvenile polyposis syndrome have been reported upon diagnosis of UC, while there have been no cases of adults with UC with solitary juvenile polyp reported in the literature. CASE SUMMARY: A 37-year-old man with a 12-year history of UC was admitted to our clinic because of increased stool frequency. UC was diagnosed at the age of 25. As the lesion was confined to the rectum, sulfasalazine suppositories or mesalazine suppositories were used. The patient was followed in an outpatient clinic, and colonoscopy was performed every one or two years. The latest examination was undertaken three years prior in the presence of proctitis. Recently, the patient complained of three to five bowel movements a day. There was mucus in the stool but no visible blood. Colonoscopy revealed a solitary polyp, about 1.5 cm in diameter, with a short and broad peduncle in the transverse colon surrounded by congestive and edematous mucosa. The patient had no family history of colorectal polyps or cancer. The polyp was successfully removed by endoscopic mucosal resection. Histopathological examination revealed that the polyp was a juvenile polyp without any malignant signs. Immunohistochemical staining for p53 showed wild-type expression and p53 overexpression was not detected. Ki-67 labeling index was 3%. CONCLUSION: This is the first case of an adult UC patient with a solitary juvenile polyp at the 12-year follow-up. The correlation between juvenile polyps and the activity of IBD needs further study.