Filiform polyposis presents a characteristic radiographic appearance consisting of long, filamentous filling defects in an otherwise normal colon. It has previously been reported in patients with a prior history of ulcerative colitis and in one patient with granulomatous colitis. The authors document its development in patients with ulcerative and granulomatous colitis. The authors have also seen a solitary filiform polyp in a patient with previously undiagnosed inflammatory bowel disease, and filiform polyps in the stomach in a patient with documented Crohn disease involving the small bowel. It is believed that this represents a nonspecific sequela of diffuse mucosal inflammation; it should not be mistaken for a neoplastic form of polyposis.