S6389 Dark Pigment, Benign Process: A Rare Case of Gastric Pseudomelanosis

Introduction: Pseudomelanosis of the stomach is rare and has been reported in association with chronic medical conditions (such as chronic renal failure, hypertension, or diabetes), chronic oral iron supplementation, and certain medications (e.g., antihypertensives, hydralazine, furosemide). The clinical significance is generally benign, and the condition is usually discovered incidentally during endoscopy performed for unrelated reasons. In contrast, true melanosis may be seen in association with metastatic melanoma, where melanin pigment is present due to tumor cell infiltration. Case Description/Methods: Sixty-eight-year-old man with past medical history of colon cancer, heart failure with preserved ejection fraction, type 2 diabetes presented with the complain of dizziness, Shortness of breath, dark stool and heme positive stool. On initial laboratory evaluation patient was found to have hemoglobin levels of 6.7 mg/dl with mean corpuscular volume of 75. consistent with microcytic anemia due to iron deficiency anemia. Patient had colon cancer diagnosed back in 2013 and had undergone hemicolectomy. Patient didn't had any follow up colonoscopy since then as he was lost in follow up. Patient received 1 packed red blood cells blood transfusion and his hemoglobin increased to 8.6 mg/dl. Gastroenterology was consulted and patient underwent upper gastrointestinal (GI) endoscopy and colonoscopy. Upper GI endoscopy showed chronic gastritis, mild inflammation without bleeding characterised by granularity was found in the gastric fundus. Linear black pigmentation was seen along with gastritis, probably secondary to diabetes vs pseudomelanosis. Biopsy was taken. Biopsy from stomach body and lesser curvature was consistent with oxyntic mucosa with mild congestion and melanosis. no Helicobacter pylori was identified. Discussion: Usually, pseudomelanosis strikes around the sixth or seventh decade of life. It has been associated with enteric iron, diabetes mellitus, chronic renal failure, upper gastrointestinal hemorrhage, and hypertension or therapy of hypertension. It is unknown exactly what could cause stomach pseudomelanosis. Drug-induced etiologies do not call for particular therapy. Still, it's crucial to deal with any underlying reasons of iron excess. The aging patient population, particularly as more patients acquire the related medical comorbidities linked in the development of this disorder, may lead to an increasing frequency of the diagnosis of pseudomelanosis of the upper gastrointestinal tract over time.