RESUMO
Amyloidosis is known as a disease caused by the deposition of a insoluble and fibrous amyloid protein in the extracellular space of various organs and tissue. Intestinal amyloid deposition may develop motility disturbance, malabsorption, bleeding and perforation. A 70-year old woman with lower abdominal pain, watery diarrhea was admitted and had the past history of diabetes mellitus, hypertension for 8 years and rheumatoid arthritis for 10 year. On colonoscopic examination for evaluation of diarrhea, multiple edematous and shallow ulcers was found from distal sigmoid to terminal ileum. A green colored positive birifringent stained amorphous material was found in polarizing microscopy of colon biopsy specimen stained with Congo-red on microscopic examination,. We report a case of amyloidosis causing colon ulcers confirmed by colonoscopic biopsy with review literature.