A Case of Gastrointestinal Amyloidosis: 1300

Purpose: An 80-year-old male was referred to gastroenterology for new onset constipation, colon cancer surveillance, and findings of a thickened sigmoid colon by abdominal CT (Figure 1). Prior to referral, this patient was undergoing extensive work-up for a plasma cell dyscrasia. In addition, he began to demonstrate worsening kidney function and developed diastolic heart failure, which, in combination with his plasma cell dyscrasia, was highly suspicious for systemic amyloidosis. The patient eventually underwent cardiac biopsy for new onset diastolic heart failure, which was positive for amyloidosis. He was eventually referred to GI with subsequent colonoscopy (Figure 2) and microscopic investigation (Figure 3-4), also consistent with amyloidosis.FigureFigureFigure: Thickening of submucosal blood vessel walls from amyloid deposition.Figure: Submucosal blood vessels with thickened walls secondary to amyloid deposition. These vessels have been stained with congo red with resulting apple green birefringence under polarized microscopy.