Massive Upper and Lower GI Bleed from Simultaneous Primary (AL) Amyloidosis of the Stomach and Transverse Colon in a Patient with Multiple Myeloma.

Symptomatic primary (amyloid light-chain or AL) amyloidosis of the gastrointestinal (GI) tract is very rare. Most of the patients with symptomatic involvement of the GI tract present with altered motility, malabsorption, or bleeding. We report a case of gastric and colonic amyloidosis on anticoagulation presenting with massive upper and lower GI bleeding. A 67-year-old lady known to have multiple myeloma and AL amyloidosis on rivaroxaban presented with massive upper GI bleeding. Esophagogastroduodenoscopy showed a mass lesion (3 × 7 cm) located along the greater curvature in the body/antrum with active bleeding. Mucosal biopsies revealed amyloid deposition. She underwent partial gastrectomy and recovered well after surgery, and was discharged home on rivaroxaban. The patient presented again 4 weeks after discharge with bleeding per rectum, and a colonoscopy revealed a large mass in the proximal transverse colon with active bleeding. Biopsy of the mass showed amyloid deposition. At this point, the patient declined any further intervention. Rivaroxaban was discontinued, the rectal bleeding stopped, and she was discharged home with no further episodes of GI bleed. Amyloidosis of the GI tract presenting with massive GI bleed is extremely rare and is thought to be related to small-vessel fragility due to amyloid infiltration and impaired hemostasis caused by factor X deficiency. Even though GI bleeding with amyloidosis is spontaneous, use of anticoagulation could activate such episodes in these patients. Caution should be exercised with the use of anticoagulation in patients with amyloidosis involving the GI tract, and colonoscopy should be considered in patients with gastric amyloidosis.