A CASE OF PRIMARY AMYLOIDOSIS WITH MULTIPLE GASTROINTESTINAL LESIONS

Abstract

A 68-year-old man presented with a four-week history of appetite loss and body weight loss of 8 kilograms. Gastroduodenal endoscopic examination demonstrated a stomal ulcer and innumerable fine granules all over the duodenum. Colonoscopic examination demonstrated multiple polypoid protrusions with redness and erosion especially in the sigmoid colon and rectum. Biopsy specimens obtained from them revealed amyloid infiltration of the submucosal layer of the stomach, duodenum and colon. These materials were stained orange with Congo red. When the tissue was examined under polarizing microscope, Congo red produced a green birefringence of amyloid. Blood chemistry showed hypoproteinemia. Serum and urine protein electrophoresis revealed a monoclonal gammopathy which on immunoelectrophoresis proved to be κ light chain. No evidence of multiple myeloma was noted in bone marrow examination. The diagnosis of primary amyloidosis was made. Stool analyses revealed fatty stools and the average α₁-antitrypsin clearance was very high. Primary amyloidosis caused malabsorption syndrome and proteinlosing enteropathy. Autopsy showed multiple polypoid protrusions with redness and erosion in the small intestine.