B5-066 Pancreas Flashcards
islets of langerhans
endocrine or exocrine?
endocrine
a-cell
b-cell
d-cell
endocrine or exocrine?
endocrine
glucagon
endocrine or exocrine?
endocrine
insulin
endocrine or exocrine?
endocrine
somatostatin
endocrine or exocrine?
endocrine
acinar cells
endocrine or exocrine?
exocrine
a-cells secrete
glucagon
b-cells secrete
insulin
produce and transport enzymes to the duodenum
acinar cells
- extension of intercalated duct cells
- produce bicarbonate
centroacinar cells
secretion of digestive enzymes, fluid and bicarb
endocrine or exocrine?
exocrine
the absence of proper pancreatic secretion may eventually cause
malnutrition
due to maldigestion/absorption
digestive enzymes are produced by […] cells
acinar
when chyme comes in contact with the intestinal mucosa, it activates
pro-entropeptidase –> enteropeptidase
cleaves trysinogen to trypsin
zymogens
3
chymotrypsinogen
procarboxypeptidases
proelastase
premature enzyme activation is prevented by 4 mechanisms..
- packaging of zymogens
- intracellular calcium homestasis
- acid-base balance prevents rise in pH
- protease inhibitors secreted by acinar cells
produced by centroacinar (ductal) cells
bicarb
key event in pancreatitis
premature trypsinogen activation
caused by elevated Ca+
breaks down starch and disaccarides in the cephalic phase
pancreatic amylase
breaks down triglycerides in the cephalic phase
pancreatic lipases
breaks down nucleic acids
pancreatic ribonuclease and deoxyribonuclease
stimulates pancreatic bicarbonates and protein secretion
VIP
inhibit pancreatic bicarb and protein secretion
PP
pancreatic polypeptide
stimulates gastic acid secretion
released from G cells
gastrin
- stimulates secretion of pancreatic enzymes
- contraction of gallbladder
- delivery of bile into small intestine
CCK
- stimulates secretion of water and bicarb from the pancreas and bile ducts
- inhibits gastrin secretion
- stimulates bile production
secretin
released due to the presence of peptides and amino acids in the gastric lumen
gastrin
released in the presence of fatty acids and amino acids in the small intestine
CCK
released due to acidic pH in the lumen
secretin
individuals with celiac disease have reduced
CCK
reduces pancreatic secretions and gallbladder contractions
most common cause of exocrine pancreatic insufficiency
chronic pancreatitis
abnormal sticky mucus that blocks bile and pancreatic ducts
Cystic fibrosis
cause of exocrine pancreatic insufficiency
9/10 CF patients depend on
PERT
in CF, lack of Cl- in lumen leads to
reduced H2O in lumen
causes of exocrine pancreatic insufficiency
4
- obstruction of biliary or pancreatic duct
- pancreatic cancer
- previous pancreatic surgery
- DM1
major characteristics of EPI
5
- frequent diarrhea
- gas/bloating
- stomach pain
- steatorrhea
- weight loss
20% of patients with chronic pancreatitis develop
EPI
EPI is treated with
PERT
gold standard for diagnosis of EPI
72 hr fecal fat test
- lipid soluble vitamin deficiency
- fecal elastase <200
- MPD dilation on imaging
high clinical suspicion for
EPI
fecal elastase <15
high clinical suspicion
EPI
avoid […] in the treatment of EPI, they can make steatorrhea worse
calcium containing antacids
must be taken with a PPI or H2 blocker
viokace
non-enteric coated
enteric coated/delayed release PERT therapy options
creon
pancreaze
pertyze
etc
what PERT medication should be avoided in the treatment of CF?
non-enteric coated (viokace)
require PPI or H2 inhibitor
associated with a higher number of hospitalizations for PH in CF patients
PPI
most common side effect of PERT therapy
hyperglycemia or hypoglycemia due to rate of amylase action
two major risk factors for chronic pancreatitis
alcohol
tobacco
- hypertrophy/dystrophy of nerves
- lymphocyte infiltration/fibrosis
chronic pancreatitis
characterized by irreversible damage that alters the organ’s normal structure and function
chronic pancreatitis
major symptom is chronic pain starting in epigastrium and radiating toward back
chronic pancreatitis
patchy, focal disease characterized by mononuclear infiltrate and fibrosis
chronic pancreatitis
involves a large portion of the entire pancreas with a predominantly neutrophilic inflammatory response
acute pancreatitis
serum amylase and lipase concentrations tend to be […] in chronic pancreatitis
normal
serum amylase and lipase tend to be [….] in acute pancreatitis
elevated
- upper abdominal “piercing” pain that travels to back
- aggravated by eating
- pain is always present but for variable periods of time
acute pancreatitis
- pain is constant, severe, radiates to back
- “gnawing”
- does not always present with pain
chronic pancreatitis
- acute inflammation
- acute abdominal pain
- elevated pancreatic serum enzymes (<24 hrs from onset)
- self-limited
acute pancreatitis
- pancreatic serum enzymes not elevated
- fibrosis and ductal obstruction
- permanent loss of function
chronic pancreatitis
what is considered chronic alcohol use that would lead to chronic pancreatits?
1 bottle of wine or 6-pack per day
for a decade
30% of chronic pancreatitis is
cause
idiopathic
autoimmune pancreatitis is associated with
SLE
how does chronic alcohol use cause pancreatitis?
- ethanol disturbs the Ca+ homeostasis, causes oxidative stress
- activates trypsin prematurely
predominate in males
large or small duct disease
large
- calcium carbonate stones
- diffuse pancreatic calcifications
- dilation visible on diagnostic imaging
large or small duct disease
large
- normal imaging
- non-dilated main pancreatic duct
- no pancreatic calcification
large or small duct disease
small
predominate in females
large or small duct disease
small
fecal elastase will be […] in chronic pancreatitis
abnormally low
hypercalcemia
acute or chronic pancreatitis?
chronic
hypocalcemia
acute or chronic pancreatitis?
acute
monitored to evaluate efficacy of PERT
fecal fat
serum amylase/lipase rarely elevated
acute or chronic pancreatitis?
chronic
steatorrhea occurs when lipase production is less than […]% of normal levels
10
chronic pancreatitis patients should be assessed frequently for […] and […] due to fat soluble vitamin deficiency
clotting function
bone density
management of chronic pancreatitis
- eliminate precipitating factor
- mangement of pain
- PERT
effective at reducing symptoms in chronic pancreatitis patients with an autoimmune etiology
steroids
chronic pancreatitis is caused by […] in most cases
alcohol abuse
a a-cell tumor would secrete […] and cause […]
glucagon
hyperglycemia
a b-cell tumor would secrete […] and cause […]
insulin
hypoglycemia
a d-cell tumor would secrete […] and cause […]
somatostatin
diabetes, steatorrhea
a g-cell tumor would secrete […] and cause […]
gastrin
zollinger-ellison syndrome
an acinar cell tumor would secrete […] and cause […]
pancreatic enzymes
pancreatitis
a deficiency in vitamin A would cause
night blindness
a deficiency in vitamin K would cause
easy bruising
without exocrine function of the pancreas, […] and […] can not be digested/absorbed
dietary lipids
fat soluble vitamins
- stimulates pancreatic release of bicarbonate and water
- inhibits gastrin production by stomach
secretin
stimulates pancreatic enzyme release
CCK
most common causes of EPI
2
- chronic pancreatitis
- cystic fibrosis
how does CF cause EPI?
thick mucus in the pancreas blocks pancreatic enzymes from entering the small intestine
most specific test to evaluate chronic pancreatitis
fecal elastase
non-enterically coated PERT should be administered with a
PPI
prevents acid inactivation of enzyme
released from duodenum in response to amino acids and fatty acids
CCK