Exocrine Pancreas & GI Tract Flashcards
What do acinar cells of the exocrine pancreas do?
aids in digestion
What are some products of the exocrine pancreas?
digestive enzymes: lipase, amylase
zymogens: trypsinogen, proelastase
trypsin inhibitor
bicarbonate
What is the red outline?
acinus
What diseases do we test for regarding exocrine pancreatic assessment?
- pancreatitis
- exocrine pancreatic insufficiency (EPI)
What are the available tests for exocrine pancreatic assessment?
traditional “leakage” enzymes (chemistry): amylase, lipase
immunoassays (auxiliary tests)
- pancreatic lipase immunoreactivity (PLI)
- trypsin-like immunoreactivity (TLI)
What is the pathogenesis of pancreatitis?
What are some causes of pancreatitis?
- Dietary indiscretion
- Idiopathic
- Duct obstruction (parasites, masses)
- Ischemia (trauma, hypovolemia, thrombosis)
- Direct cellular injury (infections, toxins, drugs)
- Local extension (biliary or GI disease)
What are clinical signs of acute pancreatitis? Which species commonly gets this?
ranges from mild edematous to severe necrotizing or hemorrhagic
dogs: acute abdomen with V, D, abdominal pain
cats: non-specific with lethargy, anorexia
DOGS
What are clinical signs of chronic pancreatitis? Which species commonly gets this?
vague, waxing and waning, non-specific signs
CATS
What are the classic enzyme changes to pancreatitis?
↑ amylase
↑lipase
↑PLI (pancreatic lipase immunoreactivity)
± ↑TLI (tyrosine-like immunoreactivity
What are chemistry changes regarding pancreatitis?
- hepatocellular injury
- cholestasis
- hyperglycemia
- hypocalcemia
- metabolic acidosis
- hypercholesterolemia
What does a coagulation panel look like with pancreatitis?
↑PT, ↑PTT
D-dimers, FDPs
Thrombocytopenia (or on CBC)
What is the pathogenesis of exocrine pancreatic insufficiency?
What are causes of exocrine pancreatic insufficiency?
juvenile pancreatic atrophy
chronic pancreatitis
pancreatic duct obstruction, e.g.
- fibrosis, - neoplasia
What is the proposed mechanism of action with juvenile pancreatic atrophy causing exocrine pancreatic insufficiency?
immune-mediated selective destruction of acinar cells
NOT diabetic - because endocrine portion is not destroyed
How do we assess exocrine pancreatic function?
traditional “leakage” enzymes (chemistry): amylase, lipase
immunoassays (auxiliary tests)
- pancreatic lipase immunoreactivity (PLI)
- trypsin-like immunoreactivity (TLI)
What do we see in pancreatitis regarding amylase levels?
increased amylase (>3-5x URL)
How is amylase cleared?
kidney —> affected by GFR - azotemia
liver
Increased amylase results in a(n) [increased/decreased] GFR
decreased - azotemic animal
What are the reasons for increased amylase?
- pancreatitis
- decreased GFR
- GI disease
- liver disease
- neoplasia (involving/near pancreas, SI, liver)
What do we see in pancreatitis regarding lipase levels?
increased lipase (>3-5x URL)
Increased lipase results in a(n) [increased/decreased] GFR
decreased GFR
What are causes of increased lipase?
- pancreatitis
- decreased GFR
- dexamethasone
- GI disease
- liver disease
- neoplasia (involving/near pancreas, GI, liver)
When evaluating pancreas values, what should be read together?
amylase & lipase
T/F: Increases in amylase and lipase are specific for pancreatitis
FALSE
a normal value does NOT rule out pancreatitis
When amylase and lipase are <2-3x URL, you can interpret it as ______
non-specific, often low GFR
When amylase and lipase are >3-5x URL, you can interpret it as ______
pancreatitis
When lipase is >10-20x URL, you can interpret it as ______
neoplasia (pancreatic +/- hepatic)
A 3 year-old MN golden retriever is vomiting and presents with an abdomen painful on palpation.
Neutrophilia with left shift, USG 1.048
What is the most likely cause of the increased amylase and lipase?
a. renal disease
b. neoplasia
c. pancreatitis
d. cholestasis
c. pancreatitis
Explain the azotemia, ALP, ALT, amylase, lipase, hypocalcemia, and hypercholesterolemia
What is the best laboratory test to test for pancreatitis? Why?
pancreatic lipase immunoreactivity (PLI)
It is specific for the pancreas
- NOT affected by GFR
What are immunoassays for pancreatic lipase?
species-specific tests
canine: cPLI
feline: fPLI
Regarding the SNAP PLI tests, they are [very/fairly] sensitive and can results in lots of false [positives/negatives]
fairly - 80% (4/5)
false positives (dogs with a negative test are unlikely to have pancreatitis**
What are causes of a decreased Trypsin-like immunoreactivity (TLI)?
exocrine pancreatic insufficiency
TLI may decrease before signs of EPI
What are causes of a increased Trypsin-like immunoreactivity (TLI)?
pancreatitis (not used to diagnose)
low GFR
What can mask EPI? How so?
pancreatitis or renal disease
by increasing the TLI to within normal limits
