S6083 A Case of Gastrointestinal Amyloidosis Presenting With Weight Loss

Introduction: Unintentional weight loss is a daunting symptom that often requires extensive investigations to rule out possible underlying cancer. Gastrointestinal (GI) amyloidosis occurs when insoluble protein deposits along the GI tract, causing altered function. Although well-known throughout the literature, GI amyloidosis may often be overlooked in the differential diagnosis for weight loss. Here, we present a case of GI amyloidosis presenting with weight loss. Case Description/Methods: A 69-year-old woman with a past medical history of morbid obesity status post Roux-en-Y gastric bypass and osteoporosis presented to her primary care provider with 40 pounds of weight loss, nausea, and vomiting of 2 months duration. Computed tomography of the abdomen and pelvis showed a moderate-sized para-esophageal hernia with a partially herniated gastric pouch. Esophagogastroduodenoscopy (EGD) revealed a 5 mm, acute-appearing, punched-out ulceration in the jejunum, seen 9 cm from the gastrojejunal anastomosis. Biopsies of the ulcer and the stomach revealed small intestinal and gastric mucosa with a positive Congo red stain, indicating amyloid deposition. Amyloid protein identification by mass spectroscopy showed Amyloidosis AL (kappa)-type. There was also a concern for systemic amyloidosis with renal and cardiac involvement as the patient also had acute kidney injury with a creatinine of 1.4, and an echocardiogram showed a severely dilated left atrium. The patient was referred to hematology, and she was started on systemic therapy with daratumumab, cyclophosphamide, bortezomib, and dexamethasone. Discussion: The differential diagnosis for weight loss is broad; infiltrating systemic diseases, such as amyloidosis, should be considered as a possible differential diagnosis. Pathology slides courtesy of Dr. Fadi Hatem (pathology department Rochester General Hospital).