Flashcards in Pancreas and Hepatobiliary Diseases Deck (39)
What is the duodenal mucosal response to food and acid?
S cells release secretin - stimulates biliary and pancreatic duct epithelium to secret bicarb and water
I cells cause release of CCK - enzyme secretion from pancreatic acinar cells and stimulates gallbladder contraction, relaxes sphincter of oddi
What are risk factors for pigment gallstones?
excess bilirubin --> black stones
bacterial contamination of bile - bacteria chemically alter bile --> soft brown stones
What is the pathophysiology of the development of acute pancreatitis?
inciting factor induces premature enzyme activation, immune system activation, oxidative stress, and ischemia-reperfusion injury that drive local manifestations (edema, necrosis, sequestration of fluid)
What is the pathophysiology of chronic pancreatitis?
irreparable damage to liver from number of sources
mutations that create super trypsin resistant to cleavage and inactivation
CFTR mutations impair ductal bicarb secretion
What drives the progression to pancreatic adenocarcinoma?
Over expression of growth factors (EGF, TGF-alpha)
activation of oncogenes (K ras)
inactivation of tumor suppressors (p53, p16)
paracrine effects of islet cell hormones (IGF)
overexpression of TGF beta drives fibrosis
What is the progression of lesions in pancreatic cancer?
precursor lesions within duct called PanINs
then angiogenesis, neural invasion, metasatic spread
What are exceptions to the no surgery for asymptomatic cholelithiasis rule?
extreme remote assignments (space, pilots)
liver transplant recipients (gallbladder removed)
What is the pathophysiology of biliary colic?
episodic abdominal pain caused by gallbladder attempting to contract in presence of obstructed cystic duct
What investigations should be used with biliary colic?
sonogram demonstrating cholelithiasis
absence of cholelithiasis --> CCK HIDA
What results from a CCK HIDA indicate a biliary source of symptoms of biliary colic?
diminished gallbladder EF and pain with CCK infusion
What is the pathophysiology of acute cholecystitis?
gallbladder wall is inflamed
usually caused by stasis of bile due to gallstone obstructing cystic dugt
sometimes ischemia (PAN) or inf cause
What are the clinical features of acute cholecystitis?
RUQ sharply localized pain, tenderness over gallbladder, fever, Murphy's sign
What investigations are used to evaluate acute cholecystitis?
leukocytosis, sonogram shows cholelithiasis if that's the cause, thickened gallbladder wall or pericholecystic fluid collection on sonogram
HIDA scan if still doubt - if dye concentrates in gallbladder, NOT acute cholecystitis
What is the pathophysiology of ascending cholangitis?
stagnant bile proximal to obstructed common bile duct becomes infected with bacteria (usually GNR)
What are the clinical features of ascending cholangitis?
fever, jaundice, RUQ pain = Charcot's triad
septic appearance (hypotensive)
What is Reynold's Pentad?
constellation of symptoms seen in ascending cholangitis = delirious, febrile, septic appearing (hypotensive), elderly, jaundice and tenderness in RUQ
What investigations are done in ascending cholangitis?
leukocytosis, elevations in all liver enzymes, elevated bilirubin, schistocytes and left shift, positive blood cultures
sonogram MAY show dilated common duct
What is the treatment of ascending cholangitis?
antibiotics (quinolones), repletion of fluids, urgent dcompression of duct by ECRP to remove stone or PTC
What is the treatment for acute cholecystitis?
cholecystectomy, antibiotics in toxic patients or in those with complication
What are the most common risk factors for acute pancreatitis?
choledocholithiasis (middle aged women and elderly patients)
What are the clinical features of acute pancreatitis?
sharp epigastric pain radiating to interscapular, subsequent nausea and emesis, maybe fever, volume depletion (orthostasis), decreased bowel sounds
Why are antibiotics usually not indicated in acute pancreatitis?
infection does not occur earlier than 5-7 days after symptom onset, no antibiotics before this time
What is a possible complication of acute pancreatitis and what does it cause?
Cullen sign - ecchymoses around umbilicus
Grey-turner sign - eccyhmoses in flanks or loins
What lab investigations are seen with acute pancreatitis?
elevated pancreatic enzymes (amylase, lipase)
leukocytosis, plain ab films may show focal or diffuse ileus, elevated hematocrit IF SEVERE
What is the best imaging modality for the pancreas?
ab CT with IV and oral contrast
What is the leading cause of mortality 2-3 weeks after symptom onset of acute pancreatitis?
infection of necrotic pancreas
When should multi-phasic CT be used in patients with acute pancreatitis?
diagnosis in doubt
deteriorate or fail to improve
>50 YO and unclear etiology (r/o cancer)
evidence of ongoing biliary obstruction
If the gallbladder is still present, what additional imaging test must be done to work up acute pancreatitis?
sonogram - need to look for gallstones
if choledocholithiasis --> ERCP
What determines severity of an episode of acute pancreatitis?
scoring systems up to 48 hrs from symptom onset
dev of local complications, systemic complications, need for surgery, death
patients not meeting criteria w/i 24-48 hrs not likely to be severe course (majority)