Differential Diagnosis for GI Bleed with Dark Brown Blood

• Single most likely diagnosis
  • Upper GI bleed (e.g., peptic ulcer disease): This is the most common cause of dark brown or "coffee ground" emesis, which occurs when blood is partially digested by gastric acid.
• Other Likely diagnoses
  • Gastritis: Inflammation of the stomach lining can cause bleeding, leading to dark brown blood or emesis.
  • Esophageal varices: Enlarged veins in the esophagus, often due to liver cirrhosis, can rupture and cause bleeding, which may appear dark brown.
  • Mallory-Weiss tear: A tear in the mucous membrane of the lower end of the esophagus can cause bleeding, which may be dark brown.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Aortic enteric fistula: A rare but life-threatening condition where there is a connection between the aorta and the intestine, which can cause massive GI bleeding.
  • Dieulafoy's lesion: A rare cause of GI bleeding, where a small artery in the stomach wall erodes and causes significant bleeding.
• Rare diagnoses
  • Hemobilia: Bleeding from the bile ducts into the GI tract, which can cause dark brown blood or emesis.
  • Intestinal lymphoma: A type of cancer that can cause bleeding in the small intestine, which may appear dark brown.
  • Meckel's diverticulum: A congenital anomaly of the small intestine that can cause bleeding, which may be dark brown.