Black stomach: acute gastric wall ischemia due to polycythemia of an unknown origin.

Acute ischemia of the gastric mucosa, resulting in a black stomach, is a very rare event given the blood supply of the stomach, with a rich collateral blood flow system. We present the case of a 65-year-old man, with polycythemia of unknown origin under investigation, presented to the emergency department with a history of diffuse abdominal pain and hematemesis. Blood tests revealed a hemoglobin level of 22 g/dL.Upper endoscopy revealed a black ulcerated gastric mucosa compatible with acute necrosis of the corpus and antrum of the stomach . Despite few cases described in the literature, many etiologic factors have been suggested. In this particular case, given the severe polycythemia and associated hyperviscosity, vascular compromise of the gastric blood vessels might have played a major role in the pathogenesis of the ischemic process.