Rare Finding of Concomitant Pseudomelanosis of Stomach and Duodenum

Abstract

Introduction: Pseudomelanosis (PM) of the stomach and duodenum is a rare entity and a striking finding diagnosed by upper endoscopy. It is characterized by dark pigmented stripes that, while benign in nature, are histologically composed of pigment-laden macrophages. We describe the case of an 83-year-old woman, with a complicated medical history, who was was found to have both pseudomelanosis gastri and duodeni. Although both are rare, gastric pseudomelanosis appears to be even more unusual than duodenal pseudomelanosis, with few reported cases documented in the literature thus far. Case Presentation: An 83-year-old woman past medical history of atrial fibrillation, chronic obstructive pulmonary disease, pulmonary hypertension, heart failure, non-Hodgkin Lymphoma, monoclonal gammopathy of undetermined significance (MGUS) who was referred to gastroenterology by cardiology for a determination of her bleeding risk in the context of an episode of self resolved gastrointestinal bleeding (melena) while on anticoagulation (Rivaroxaban). Patient underwent a diagnostic upper endoscopy which revealed mucosal changes in the stomach and duodenum consistent with pseudomelanosis (Figure 1&2). Pathology report revealed of pigment-laden macrophages in the lamina propria.Figure: Pseudomelanosis in the gastric antrum.Figure: Pseudomelanosis in the duodenum.Discussion: Although a benign finding, gastric and duodenal pseudomelanosis is such an infrequent and manifest condition that it can lead to an extensive, expensive, and ultimately unnecessary work-up. It is very rare to see both pseudomelanosis of stomach an duodenum in the same patient. It involves the collection of dark pigmented granules inside the macrophages of the duodenal villi's lamina propria, usually within the apical tips. Electron probe microanalysis has shown that these macrophages often contain lipomelanin, ceroid, iron sulfide, and hemosiderin. However, gastric and duodenal pseudomelanosis represents a diagnostic challenge for physicians because the precise etiology and clinical significance of this condition remain to be determined. It is typically seen in older women and has been associated with several clinical conditions, some of which include: hypertension, hemochromatosis, diabetes, chronic renal disease, and gastrointestinal bleeding. Gastric and duodenal pseudomelanosis has also been seen in connection with medications containing iron sulfate as well as certain antihypertensive medications, like furosemide, hydrochlorothiazide, propranolol, and hydralazine.