Gastric amyloidosis in a patient with dysphagia

Dysphagia is a symptom with a broad differential diagnosis. Usually, the etiology of dysphagia is benign, but it is essential to rule out serious causes. It is also critical to think outside the box when the etiology is not obvious. Herein, we describe a case of multiple myeloma that initially presented with dysphagia. An 81-year-old male patient presented with dysphagia to solid food associated with anorexia and weight loss of 22 kg over the last 6 months. The patient looked chronically ill and cachectic. Upper endoscopy showed patchy erythema in the gastric antrum. Gastric biopsy was consistent with gastric amyloidosis. Although serum and urine protein electrophoresis did not show a monoclonal (M) band, immunofixation did show elevated free kappa light chains and elevated free Kappa/Lambda ratio. Bone marrow biopsy was consistent with multiple myeloma. Although gastrointestinal involvement is common in amyloidosis, it is unusual for amyloidosis to initially present in the gastrointestinal tract. Identification and treatment of the underlying condition, e.g., multiple myeloma, can lead to regression of gastrointestinal amyloidosis.