Pseudotumoral Amyloidosis Presentation With Upper Digestive Bleeding.

Amyloidosis is a condition related to the extracellular deposition of abnormal fibrillar proteins. Gastric involvement may present as a systemic or localized form of the disease. The endoscopic presentation can vary from nodular, ulcerated, or infiltrative lesions. Clinical manifestations are nonspecific, including hyporexia, nausea, vomiting, weight loss, epigastralgia, and abdominal discomfort. Thus, amyloidosis can clinically and endoscopically mimic other diseases, such as neoplasms, syphilis, tuberculosis, and Crohn's disease, requiring a high suspicion. When it manifests with gastrointestinal bleeding, it most commonly occurs as intermittent melena. This report aims to present an unusual case of a patient with upper gastrointestinal bleeding exteriorized through melena secondary to amyloidosis with gastric involvement.