Pseudomelanosis of the stomach and duodenum: an uncommon endoscopic finding

A woman (70-years) with a history of iron deficiency anemia and chronic kidney disease presented with two weeks of abdominal pain. Upper endoscopy demonstrated the gastric and duodenal mucosa was black and speckled consistent with diagnosis of pseudomelanosis. Biopsies showed pigment-laden macrophages in the lamina propria, which stained positive for iron and Masson-Fontana trichrome stain consistent with a “melanin-like” pigment. Although an uncommon endoscopic finding, this pigment has been associated with the use of certain medications, antihypertensives and iron supplements, and systemic illnesses, including hypertension, chronic kidney disease, gastric hemorrhage, and diabetes mellitus.