S1818 Colonic Amyloidosis: A Rare Cause of Gastrointestinal Bleeding

Abstract

Introduction: AL-amyloidosis is a rare systemic disorder with an annual U.S. incidence of ∼2000 cases. It results from abnormally folded protein deposition. Gastrointestinal (GI) amyloidosis presents with non-specific symptoms of weight loss, abdominal pain, diarrhea, and bleeding. Endoscopic findings vary from bulky mucosal lesions to friable, ulcerated mucosa. Endoscopy and histology are crucial in making the diagnosis. Our case highlights this rare, but important, etiology of GI bleeding, and showcases the interesting endoscopic findings seen. Case Description/Methods: 79-year-old male with a history of type-2 diabetes mellitus, chronic heart failure, hypothyroidism, and coronary artery disease presented with hematochezia. Other non-specific symptoms included lower abdominal pain, constipation, early satiety, dysphagia, 40-lbs weight loss, and weakness. History was negative for heavy alcohol use. Colonoscopy 13 years prior was normal. Physical exam showed an ill-appearing male with abdominal distension and generalized abdominal pain without rebound or guarding. Labs were notable for a WBC 16, chronic iron deficiency anemia (baseline hemoglobin 9), AST 54, ALT 24, ALP 369, and creatinine 1.7. CT scan demonstrated hepatosplenomegaly with ascites and diffuse colitis. Serum ascites albumin gradient was >1.1. Colonoscopy showed bulky clot-like masses protruding from the mucosa with patchy colitis throughout. Biopsies were positive for Congo Red stain, making the diagnosis of AL-kappa type amyloidosis. He was started on the appropriate therapy, but his clinical course deteriorated with eventual death from multi-organ failure. Discussion: Colonic involvement from amyloidosis is extremely uncommon. Within the GI tract, amyloid deposits in the muscularis mucosae leading to frailty of blood vessels, impaired peristalsis, and decreased gut wall compliance. Patients present with bleeding, malabsorption, dysmotility, and protein losing enteropathy resulting in ascites, edema, and pericardial effusion. Endoscopic findings are variable with more bulky mucosal deposition seen in AL-type compared to ulceration and friability seen in AA-type. Diagnosis is made by histology. Amyloidosis also may involve non-luminal organs of the GI tract, including the liver. Deposition within hepatic stellate cells promotes a fibrogenic state resulting in cirrhosis as seen in our patient. Early recognition of intestinal amyloidosis is important as it carries a poor prognosis. Multi-specialty approach is crucial for diagnosis and management.Figure 1.: A,B: Large intestine amyloid deposition noted on colonoscopy. You can see extension from mucosa in part A. C,D: Biopsy evaluation of mass on colonoscopy. D highlights positive Congo Red Staining leading to diagnosis of AL-Amyloidosis.