Acute pancreatitis (AP) is a sudden inflammation of the pancreas. Causes in order of frequency include: 1) a gallstone impacted in the common bile duct beyond the point where the pancreatic duct joins it; 2) heavy alcohol use; 3) systemic disease; 4) trauma; 5) and, in minors, mumps. Acute pancreatitis may be a single event; it may be recurrent; or it may progress to chronic pancreatitis. Mild cases are usually successfully treated with conservative measures: hospitalization, pain control, nothing by mouth, intravenous nutritional support, and intravenous fluid rehydration. Severe cases often require admission to an intensive care unit to monitor and manage complications of the disease. Complications are associated with a high mortality, even with optimal management. Signs and symptoms Common severe epigastric pain (upper abdominal pain) radiating to the back in 50% of cases nausea vomiting loss of appetite fever chills (shivering) hemodynamic instability, including shock tachycardia (rapid heartbeat) respiratory distress peritonitis hiccup Although these are common symptoms, frequently they are not all present; and epigastric pain may be the only symptom. Uncommon The following are associated with severe disease: Grey-Turner's sign (hemorrhagic discoloration of the flanks) Cullen's sign (hemorrhagic discoloration of the umbilicus) Pleural effusions (fluid in the bases of the pleural cavity) Grünwald sign (appearance of ecchymosis, large bruise, around the umbilicus due to local toxic lesion of the vessels) Körte's sign (pain or resistance in the zone where the head of pancreas is located (in epigastrium, 6–7 cm above the umbilicus)) Kamenchik's sign (pain with pressure under the xiphoid process) Mayo-Robson's sign (pain while pressing at the top of the angle lateral to the erector spinae muscles and below the left 12th rib (left costovertebral angle (CVA)) Mayo-Robson's point – a point on border of inner 2/3 with the external 1/3 of the line that represents the bisection of the left upper abdominal quadrant, where tenderness on pressure exists in disease of the pancreas. At this point the tail of pancreas is projected on the abdominal wall. Complications Locoregional complications include pancreatic pseudocyst (most common, occurring in up to 25% of all cases, typically after 4–6 weeks) and phlegmon/abscess formation, splenic artery pseudoaneurysms, hemorrhage from erosions into splenic artery and vein, thrombosis of the splenic vein, superior mesenteric vein and portal veins (in descending order of frequency), duodenal obstruction, common bile duct obstruction, progression to chronic pancreatitis, pancreatic ascites, pleural effusion, sterile/infected pancreatic necrosis. Systemic complications