Exocrine Pancreas, Gallbladder, and Liver Pathology PDF

## Exocrine Pancreas, Gallbladder, and Liver Pathology ### I. Annular Pancreas * Developmental malformation in which the pancreas forms a ring around the duodenum; risk of duodenal obstruction ### II. Acute Pancreatitis * Inflammation and hemorrhage of the pancreas * Due to autodigestion of panc...

## Exocrine Pancreas, Gallbladder, and Liver Pathology ### I. Annular Pancreas * Developmental malformation in which the pancreas forms a ring around the duodenum; risk of duodenal obstruction ### II. Acute Pancreatitis * Inflammation and hemorrhage of the pancreas * Due to autodigestion of pancreatic parenchyma by pancreatic enzymes * Premature activation of trypsin leads to activation of other pancreatic enzymes. * Results in liquefactive hemorrhagic necrosis of the pancreas and fat necrosis of the peripancreatic fat. * Most commonly due to alcohol and gallstones; other causes include trauma, hypercalcemia, hyperlipidemia, drugs, scorpion stings, mumps, and rupture of a posterior duodenal ulcer. * **Clinical Features** * Epigastric abdominal pain that radiates to the back * Nausea and vomiting * Periumbilical and flank hemorrhage (necrosis spreads into the periumbilical soft tissue and retroperitoneum) * Elevated serum lipase and amylase (lipase is more specific for pancreatic damage) * Hypocalcemia (calcium is consumed during saponification in fat necrosis) * Complications * Shock - due to peripancreatic hemorrhage and fluid sequestration * Pancreatic pseudocyst - formed by fibrous tissue surrounding liquefactive necrosis and pancreatic enzymes * Presents as an abdominal mass with persistently elevated serum amylase * Rupture is associated with release of enzymes into the abdominal cavity and hemorrhage. * Pancreatic abscess - often due to E coli; presents with abdominal pain, high fever, and persistently elevated amylase * DIC and ARDS ### III. Chronic Pancreatitis * Fibrosis of pancreatic parenchyma, most often secondary to recurrent acute pancreatitis * Most commonly due to alcohol (adults) and cystic fibrosis (children); however, many cases are idiopathic. * **Clinical Features** * Epigastric abdominal pain that radiates to the back * Pancreatic insufficiency - results in malabsorption with steatorrhea and fatsoluble vitamin deficiencies. Amylase and lipase are not useful serologic markers of chronic pancreatitis. * Dystrophic calcification of pancreatic parenchyma on imaging; contrast studies reveal a 'chain of lakes' pattern due to dilatation of pancreatic ducts. * Secondary diabetes mellitus - late complication due to destruction of islets * Increased risk for pancreatic carcinoma ### IV. Pancreatic Carcinoma * Adenocarcinoma arising from the pancreatic ducts * Most commonly seen in the elderly (average age is 70 years) * Major risk factors are smoking and chronic pancreatitis. * **Clinical Features** (usually occur late in disease) * Epigastric abdominal pain and weight loss * Obstructive jaundice with pale stools and palpable gallbladder; associated with tumors that arise in the head of the pancreas (most common location) * Secondary diabetes mellitus; associated with tumors that arise in the body or tail * Pancreatitis * Migratory thrombophlebitis (Trousseau sign); presents as swelling, erythema, and tenderness in the extremities (seen in 10% of patients) * Serum tumor marker is CA 19-9. * Surgical resection involves en bloc removal of the head and neck of pancreas, proximal duodenum, and gallbladder (Whipple procedure). * Very poor prognosis; 1-year survival is < 10%.