Filiform polyposis in Crohn's colitis mimicking toxic megacolon.

A patient with filiform polyposis in Crohn's colitis is reported. Unlike previous reports of filiform polyposis, this patient's colitis was of rapid onset and antedated development of pseudopolyps by a short duration. Additionally, unlike previous reports, the disease process was quite aggressive. The extensive degree of fissuring found throughout the bowel wall may have produced the unusually shaped polyps and caused the toxic colonic atony.