failure, hypoglycemia, dehydration, burns (Curling ulcer), intracranial lesions or trauma (Cushing ulcer), renal failure, and vasculitis These ulcers may develop within minutes to hours after the initial insult and primarily result from ischemia Hematemesis, hematochezia, melena, and/or perforation of the stomach or duodenum may accompany stress-associated ulcers TABLE 33.3 LIFE-THREATENING CAUSES OF UPPER GASTROINTESTINAL BLEEDING Ulcer Esophageal varices Hemorrhagic gastritis Vascular malformation Intestinal duplication Hematemesis following the acute onset of vigorous vomiting or retching at any age suggests a Mallory–Weiss tear These tears occur at the gastroesophageal junction due to a combination of mechanical factors (e.g., retching) and gastric acidity Preschool Period (2 to Years) Reflux, eosinophilic esophagitis, swallowed foreign bodies (if sharp or eroding the mucosal lining), and caustic ingestion can cause esophagitis leading to upper GI bleeding Idiopathic peptic ulcer disease is a common cause of GI bleeding in preschool and older children Nonsteroidal anti-inflammatory drugs (NSAIDs) and acetylsalicylic acid (aspirin) can also be a cause of gastritis in this age group Critically ill children can develop gastritis and peptic ulcers GI bleeding (hematemesis or melena) can develop in preschool children with esophagitis, gastritis, and peptic ulcers Complications, including obstruction and perforation, may occur Younger children have less characteristic symptoms, often localize abdominal pain poorly, and may have vomiting as a predominant symptom Medical child abuse, such as Munchausen syndrome by proxy, should be considered in children with recurrent episodes of GI bleeding without a clear etiology, often in the context of other social concerns School Age Through Adolescence Period Older children and adolescents describe epigastric pain in a pattern typical of adults Esophageal and gastric varices are the most common causes of severe upper GI hemorrhage in older children and are associated with portal hypertension due to hepatic and vascular disorders One-half to two-thirds of these children have an extrahepatic presinusoidal obstruction, often resulting from portal vein thrombosis, as the cause of portal hypertension A neonatal history of omphalitis with or without a history of umbilical vein cannulation may contribute Other children with portal hypertension have