124b Pancreas Disease Flashcards
pancreas - location in abdomen?
consists of what?
retroperitoneal
exocrine (majority) - acini + ducts AND
endocrine - islets of Langerhans
histo appearance of exocrine pancreas?
acinar - pink
triangular cell, basal nucleus
apical - dense pink granules (zymogen)
extensive basal ER for making/transporting granules
Normal ductal anatomy vs pancreatic divisum in pancreas?
normal - duct of wirsung to main pancreatic duct with smaller duct of santorini
divisum -separate branches (no duct of wirsung)
what occurs in acute pancreatitis?
autodigestive and inflammation
what causes acute pancreatitis in women? men?
gallstones (women) - mechanical
alcohol (men) - metabolic
+ other things
what are 3 protections against autodigestion in pancreas?
inactive precrusors (zymogens) are secreted
duodenum enterokinase (in brush border) activates trypsinogen to trypsin which activates everything else
protease inhibitors in acinar cells in case of premature activation
what do duct cells produce in pancreas?
bicarbonate and mucin
what is the key step leading to autodigestion in pancreatitis?
activation of trypsin
Pathogenesis of gallstones leading to acute pancreatisi?
Blockage ampulla of vater –> bile into pancreas
increased ductal P –> damages acinar cells/duct
alcohol - pancreatitis pathogenesis (4 ways)?
spasm/relaxation of sphincter of Oddi
Acinar cells sensitized to CCK –> zymogen activation
Alcohol metabolism in pancreas
Increased protein secretion plugs ducts
symptoms of acute pancreatitis?
rapid onset of severe, persistent pain to back
nausea and vomiting
low grade fever
hypotension
pathology appearace of acute pancreatisi?
microvascular leakage --> swollen gland lipases --> fat necrosis --> white extensive hemorrhage --> brown proteolytic activation --> loss of parenchyma inflammatory cells
lab tests for acute pancreatitis?
increase serum lipase (more specific)
increase serum/urine amylase
increase WBC
what is and what causes chronic pancreatitis?
chronic inflammatory process with fibrosis, loss of structure (exocrine then endocrine) from repeat acute from booze
pancreatic pseudocyst - what causes it? what is it made of?
acute and chronic pancreatitis
fibrotic wall (no epithelial) filled with fluid and inflammatory cells
what are the 3 types of chronic pancreatitis?
Calcified - fibrosis with stones and protein plugs from booze
Obstructive - tumor of main pancreatic duct
Inflammatory - autoimmune cause (Sjogren’s)
clincial presenation from chornic panc
maldigestion from atrophy of acinar tissue
diabetes from loss of endocrine tissue
Pseudocyst
what cell type are the most exocrine pancreatic tumors?
Ductal
risks for pancreatic carcinoma?
smoking, alcohol, chronic pancreatitis
pancreatic adenocarinoma genetics - frequent mutations
K-ras (12p) - most important/prevalent; early p53 (17p) BRCA2 (13q) Rb gene **cancers need multiple gene mutations**
K-ras - role?
GTPase for signal transduction pathway
mutation makes it always active
in what part of the pancreas does pancreatic cancer occur most often?
head with fibroblast proliferation -> obstructs common bile duct –> jaundice
body vs head for pancreatic cancer presentation and spread
head - jaundice; liver, lungs, lymph nodes
body/tail - thromboembolism; subcutaneous, extensive mets
stage if extension to peripancreatic tissue?
T3 (T4 celiac axis and unresectable)
early diagnosis of pancreatic ca?
MRI - food early, but expensive serum marker (CA 19-9) for advanced disease
