pancreas pathophys Flashcards
Which pancreatic enzymes are active when secreted
amylase and lipase
What causes acute pancreatitis
when pancreatic enzymes are inappropriately and prematurely activated resulting in autolysis of the gland. This may result in severe inflammation and/or necrosis of pancreatic tissue. Caused when pancreatic duct is obstructed resulting in stagnation of pancreas enzymes in duct lumen and activation of enzymes
acute pancreatitis symptoms
severe pain in the upper abdomen, sometimes radiating to the back, and nausea/vomiting. Low-grade fevers may accompany this. The pain is usually intolerable
Consequence of acute pancreatitis
Lipase released from dying acinar cells breaks down fat, liberating free fatty acids which precipitate with calcium and form insoluble soaps. In severe pancreatitis, there may be frank coagulation necrosis of the gland and/or hemorrhage into the retroperitoneum
acute pancreatitis histology
necrosis of pancreatic tissue is associated with intense infiltrates of neutrophils and apoptosis of epithelial cells
acute pancreatitis diagnosis
history/PE, serum levels of amylase and lipase which are elevated b/c enzymes leak out of inflammed pancreas into blood. Ultrasound, CT
Acute pancreatitis treatment
NPO, IV pain meds, time (self limited). If gallstones, cholecystectomy to remove gallbladder or ERCP to extract stones.
alcohol induced acute pancreatitis pathogenesis
damage of acinar cell > release of enzymes > lipase causes fat necrosis, proteases cause vascular damage
Stone induced acute pancreatitis pathogenesis
obstruction > secretagogue effect > leakage of enzymes through injured ductule > lipase causes fat necrosis and proteases cause vascular destruction
complications of acute pancreatitis
ileus (paralysis of gut), intra-abd hemorrhage, pseudocyst formation. Pancreatic necrosis, bowel obstruction, shock, respiratory or renal failure, death
what is a pancreatic pseudocyst
•Collection of pancreatic fluid, debris surrounded by wall of granulation tissue - lacks epithelial lining. Results from ductal disruption, necrosis or both. Most resolve with time.
What respiratory disease is associated with pancreatic necrosis
Adult respiratory distress syndrome (ARDS). Delayed onset, leads to respiratory failure. Fully reversible, treatment is support
Causes of chronic pancreatitis
repeated acute pancreatitis, usually from chronic alcohol use.
clues to gallstone pancreatitis
elevated liver enzymes, dilated bile duct
Chronic pancreatitis macro and microscopic features
macro: hard fibrous tissue, atrophy of gland, pancreatic juice is viscous with calcifications, possible pseudocysts, ductal strictures Micro: boad bands of scar tissue, lymphocytes and/or plasma cells, strictures of ducts, calcified pancreatic duct stones
Chronic pancreatitis symptoms
chronic pain (epigastric radiates to back), malabsorption resulting in steatorrhea, permanent loss of pancreatic function (hypo or hyperglycemia)
Which features of chornic pancreatitis cause pain, exocrine failure, nausea, endocrine failure
Ductal strictures/stones cause pain and exocrine failure. Pancreatic pseudocysts cause pain, nausea/vomiting (depending on what’s compressed). Acinar destruction causes exocrine failure. Diabetes causes endocrine failure (late)
Other causes of chronic pancreatitis
Cystic fibrosis, hereditary pancreatitis, hyperlipidemia
pancreatic insufficiency symptoms and nutrients involved
weight loss (fat), steatorrhea (fat), bleeding problems (Vit K), anemia (Vit B12), weakness/edema (protein), watery diarrhea (CHO, protein)
Mechanisms of steatorrhea
decreased lipase and colipase in duodenum. Decreased duodenal pH leads to inactivation of pancreas enzymes and bile acid precipitation
Chronic pancreatitis diagnosis
history, PE, plain X ray shows pancreatic calcifications, CT shows dilated duct, atrophy, calcifications and pseudocysts. Secretin test, ERCP, endoscopic US are all more accurate
What is secretin test
secretin given IV- [HCO3] increase of less than 80 mEq/l suggests pancreatic obstruction or failure
Chronic pancreatitis treatment
ethanol avoidance, pancreas enzyme replacement for steatorrhea, treat duct obstruction with dilation stent or stone removal, celiac nerve block for pain, surgery, pancreatectomy with islet cell transplant in young patients
Pancreatic cancer presentation
Jaundice, dark urine, pruritus - Bile duct obstruction (tumors in head). Late Abdominal or back pain - Capsular distension or nerve invasion. Weight loss. Nausea/vomiting (late) – Duodenal or gastric obstruction. Hormonal excess (neuroendocrine) -insulin, glucagon, gastrin, VIP
Pancreatic neuroendocrine tumor
slow growing, good prognosis. Islet cell origin. Symptoms of hormonal excess. Octreotide scan used for small NETs
Autoimmune pancreatitis
Diffuse or focal enlargement of pancreatic parenchyma. Infiltration by IgG-4 + plasma cells and lymphocytes. Males, typically ages 40-70
Autoimmune pancreatitis symptoms
abdominal pain, jaundice, weight loss, (rarely) pancreatitis
Autoimmune pancreatitis diagnosis and treatment
•Diagnosis: CT/MRI, serum IgG-4, EUS, ERCP, and occasionally FNA/biopsy. Treatment: PO corticosteroids x 6 weeks, biliary stenting for symptom relief
