Duodenal siderosis: a rare clinical finding in a patient with duodenal inflammation

An 84-year-old man without any signifi cant past medical history (PMH) was admitted for anemia and weight loss. Th ere was no history of gastrointestinal bleeding or iron supplement use. Physical examination was benign except for pallor. His labs showed: hemoglobin 6.8 (11.0-15.6) g/dL, serum iron 30 (65-175) μg/dL, total iron binding capacity 141 (179-378) μg/dL, ferritin 416 (22-275) ng/dL, and transferrin 109 (188-341) mg/dL. An esophagogastroduodenoscopy (EGD) was performed which revealed a duodenal polyp, and duodenitis with dark brown pigmentation (Fig. 1A,B). Histopathologic examination of this pigmented mucosa revealed glandular deposition of brown pigments (Fig. 2A), confi rmed to be iron with Prussian blue stain (Fig. 2B). Iron deposition in gastric and duodenal mucosa has been found in association with oral iron medications, alcohol abuse, blood transfusions, hemochromatosis, and decompensated cirrhosis with esophageal varices [1,2]. Th e endoscopic fi nding of mucosal iron deposition is highly variable ranging from yellow-brown to black mucosa, with associated ulcerations or regenerative polyps [3]. Histologically, three main patterns of iron deposition were described by Marginean et al [1]. Type A (“nonspecifi c”) variant is free fl oating siderosomes located intracellularly in macrophages, stroma, and epithelium. Type B (“iron-pill gastritis”) is large clumps of fi brillar iron located extracellularly and in blood vessels, macrophages, and epithelium. Type C (“gastric glandular”) variant is free fl oating siderosomes located in deeper glands of the antrum and fundus. Iron deposition in duodenal mucosa is extremely rare and isolated duodenal siderosis has never been reported in the literature. Without signifi cant PMH and predominantly intraglandular, iron deposition not entirely fi tting any of those patterns has been described by Marginean et al [1]. Our case may represent an “idiopathic” variant of gastroduodenal siderosis. Recognition of variable patterns of deposition may guide further workup and treatment of iron overload cases.