<prompt> Most common cause of upper GI bleeding?Gastric ulcerEsophageal varicesGastritisCarcinoma stomach  <response>: Ans. a Gastric ulcer. Ref. Harrisons 16th ed., 235UGIB upper gastrointestinal bleeding is defined as bleeding derived from a source proximal to the ligament of Treitz. Hematemesis and melena are the most common presentations of acute UGIB, and patients may present with both symptoms. Occasionally, a brisk UGIB manifests as hematochezia.Differential diagnoses for UGIB: Peptic ulcer - 50 cases- Esophageal varices- Gastric varices Mallory-Weiss tear- Esophagitis- Neoplasm Hemorrhagic gastritis- Angiodysplasia- Hemobilia Pancreatic pseudocyst- Pancreatic pseudoaneurysm- Aortoenteric fistula Dieulafoy lesion submucosal persistent caliber artery in stomach 