341 Pancreas Flashcards
What stimulates the secretion of water and electrolytes from the pancreas
Gastric acid stimulates the release of secretin from the duodenal mucosa which stimulates the release of water and electrolytes from the pancreas
What cells release CCK
Ito cells of the duodenal and jejunal mucosa
Exerts significant control over pancreatic secretions
Parasympathetic nervous system (via the vagus nerve)
Ion of primary physiologic importance within pancreatic secretion
Bicarbonate
Where is 93% of bicarbonate derived
ductal cells secrete bicarbonate predominantly derived from plasma (93%)
General types of enzyme secreted by the pancreas
amylolytic, lipolytic and proteolytic enzymes
Examples of amylolytic enzymes and what does it do
amylase; hydrolyzes startch to oligosaccharides and disaccharide to maltose
Examples of lipolytic enzymes
lipase, phospholipase A2, and cholesterol esterase
Examples of proteolytic enzymes and what does it do
endopeptidases, exopeptidases, elastase; act on internal peptide bonds of protein and polypeptides
Enzymes found in doudenal mucosa which cleaves trypsinogen to trypsin
enterokinase
Stimulatory neurotransmitters of the pancreas
acetylcholine and gastrin releasing peptide
extrinsic innervation of the pancreas
vagus nerve
How is autodigestion in the pancreas mantained
pancreatic proteases are in proenzyme form;intracellular calcium homeostasis, acid-base balance, synthesis of protective protease inhibitors
Accounts for 80-90% of acute pancreatitis cases in the US
gallstones and alcohol
Leading cause of pancreatitis in 30-60% of cases
gallstones
What size of the gallstone has a 4x greater risk of acute pancreatitis
one gallstone less than 5 mm
Causes pancreatitis in 1.3-3.8% of cases
hypertriglyceridemia
What is the level of triglycerides that will trigger acute pancreatitis
serum triglyceride level of more than 1000 mg/dl
what does apolipoprotein CII do
activates lipoprotein lipase which clears chylomicrons from the blood strea
currently accepted pathogenic theory for acute pancreatitis
autodigestion
What happens in autodigestions
pancreatic enzymes are activated in the pancreas acinar cell than than in the intestinal lumen
How many phases of pancreatitis
3 phases
Pathophysiology of acute pancreatitis. Characterized by intrahepatic digestive enzyme activation and acinar cell injury
Initial phase
Pathophysiology of pancreatitis. Activation, chemoattraction, and sequestration of leukocytes and macrophages in the pancreas
Second phase
Pathophysiology of pancreatitis. Effects of activated proteolytiz enzymea and cytokines released by inflamed pancreas to distant organs
Third phase
Major symptom of acute pancreatitis
abdominal pain
Mechanisms that lead to shock in patient with pancreatitis
hypovolemia from extravasaation of blood and plasma into the retroperitoneal space; increased formation and release of kinin peptides leading to increased vascular permeability; systemic effects of proteolytic and lipolytic enzymes released into the circulation
What leads to jaundice in pancreatitis? Is it common
Jaundice is uncommon. It is due to compression of the intrapancreatic portion of the CBD or passage of biliary stone or slude brought about by the edema of the head of the pancreas
What is Cullen sign
Bluish discoloration around the umbilicus as a result of hemoperitoneum
What is Turner sign
Blue red purple or green brown discoloration of the flanks
Perfect test for acute pancreatitis.
Lipase. It is more specific than amylase.
When does amylase return to normal
3-7 days even if patients still have clinical signs of pancreatitis
Until how many days does lipase remain elevated
lipase remains elevated for 7-14 days
True or false. Serum amylase can increase in cases of acidemia when blood pH is less than 7.32
True.
True or false. Patients with DKA can have elevated serum amylase even without evidence of pancreatitis
True
Harbinger of more severe disease in acute pancreatitis
hemoconcentration. Hct more than 44%
True or false. Hypoglycemia in common in acute pancreatitis
False. Hyperglycemia is common from decreased insulin release and increased glucagon release
Definition. Acute inflammation of the pancreatic parenchy and peripancreatic tissues but without recognizable tissue necrosis.
interstitial pancreatitis
Definition. Inflammation associated with pancreatic parenchymal necrosis and or peripancreatic necrosis
necrotizing pancreatitis
Definition. Encapsulated collection of fluid with a well defined inflammatory wall outside the pancreas with minimal or no necrosis.
pancreatic pseudocysts
When does pancreatic pseudocyts appear
more than 4 weeks after onset of interstitial pancreatitis
Definition. Peripancreatic fluid associated with interstitial edemaous pancreatitis with no associated peripancreatic necrosis
Acute pancreatic fluid collection
When does acute pancreatic fluid collection occur
within the 4 weeks after onset of intersitial pancreatitis
Definition. A collection containing cariable amounts of both fluid and necrosis associated with necrotizing pancreatitis
Acute pancreatic necrotic collection
When does walled off necrosis (WON) occur?
Occurs more than 4 weeks after onset of necrotizing pancreatitis
Definition. Mature encapsulated collection of pancreatic and or peripancreatic necrosis that has developed a well defined inflammatory wall
Walled-off necrosis (WON)
When does serum bilirubin levels result to normal in acute pancreatitis
normal in 4-7 days
True or false. Jaundice in acute pancreatitis is transient
True.
How is acute pancreatitis diagnosed
2 out of 3. typical abdominal pain in epigastrium which radiate to the back, 3x or greater elevation of serum lipase and or amylase, confirmatory findings of acute pancreatitis on abdominal imaging
True or false. It may be difficult to differentiate acute cholecystitis from acute pancreatitis as both can present with elevated amylase.
True.
Test to differentiate DKA from acute pancraetitis
Serum lipase is normal in DKA
Define organ failure and what systems must be assessed
Organ failure in 2 or more sytems: respiratory, cardiovascular, renal
Most important clinical finding in regard to severity of the acute pancreatitis
persistent organ failure of more than 48 hours
When is late phase in acute pancreatitis
Protracted course illness
Phases of acute pancreatitis
early less than 2 weeks hospital course and late more than 2 weeks
True or false. CT imaging is done as early as possible.
False. CT imaging not needed or recommended during the first 48 hours of acute pancreatitis. After the 48 hours, it is done to evaluate for local complications
Greatest importance during the late phase of acute pancreatitis
CT imaging
Severity classes of acute pancreatitis
Mild, moderate, severe
When is acute pancreatitis mild
Without local complications or organ failure. Disease is self limited and subsides spontaneously in 3-7 days
When is acute pancreatitis moderate
there is transient organ failure than resolves in less than 48 hours
when can oral intake be resumed in acute pancreatitis
when patient is hungry, has normal bowel function and no nausea and vomiting
When is acute pancreatitis severe
when organ failure persists for more than 48 hours
Types of pancreatitis based on imaging
intersitial and necrotizing
Imaging of interstitial pancreatitis
diffuse gland enlargement with homogenous contrast enhancement
Imaging of necrotizing pancreatitis
lack of pancreatic parenchymal enhancement by contrast and presence of peripancreatic necrosis
How is fluid resuscitation done in acute pancreatitis
15-20 ml/kg bolus then 2-3 ml/kg per hour to maintaine urine output more than 0.5 ml/kg per hour
Preferred IV fluid in acute pancreatitis and why
Lactated Ringers; shown to decrease inflmmation than normal saline
Recommended to ensure adequate fluid resuscitationn
Hematocrit and BUN every 8-12 hours
Strong evidence that sufficient fluids are being administered
Decrease in hematocrit and BUN during the first 12- 24 hours
How to respond to rise in hematocrit or BUN on serial measurement
repeat volume challenge of 2 Liters then followed by increasing fluid rate at 1.5 ml/kg/hr
If still despite repeat volume challenge, Hct and BUN continues to rise, what to do
for ICU for hemodynamic monitoring
What to do in patient with evidence of ascending cholangitis on top of gallstone pancreatitis
ERCP within 24-48 hours of admission
When should cholecystectomy be done in patient with gallstone pancreatitis
during admission or 4-6 weeks after discharge
Effective at decreasing pancreatitis after ERCP
pancreatic duct stenting and rectal indomethacin
When should feeding be considered in acute pancreatitis
enteral feeding considered 2-3 days after adminsion after abdominal pain has resolved
True or false. Patients with necrotizing pancreatitis should be given prophylactic antibiotics
False. No role. If patient appear septic, antibiotics may be given and discontinued when cultures turned negative
True or false. Acute pancreatitis may present with sterile necrosis and managed conservatively without antibiotics
True. No antibiotics if no growth on culture to avoid opportunistic and fungal infection
Presents with increasing abdominal pain or shortness of brath in setting of enlarging fluid collection on MRCP or ERCP
Pancreatic duct disruption
How is pancreatic duct disruption managed
Bridging pancreatic stent for at least 6 weeks
Most common etiologic factor for recurrent pancreatitis
alcohol and cholelithiasis
Why is there an increased incidence of pancreatitis in patients with AIDS
high incidence of infection involving the pancreas such as CMV, cryptosporidium and MAC; medication induced such as TMP SMX, pentamidine, protease inhibitors
True or false. In chronic pancreatitis, the damage is irreversible.
True.
Strongly linked to chronic pancreatitis and why
smoking increases susceptibility to pancreatic autodigestion and predispose to CFTR dysfunction
Most common cause of chronic pancreatitis in adults. In children?
Adult: alcoholism. Children: cystic fibrosis
Marker for autoimmune pancreatitis
Elevated serum levels of IgG4; ANA and RF may be positive
How is AIP diagnosed
Mayo Clinic HISORt criteria 1 or more of the following. Histology. Imaging: mass in head of pancreas. Serology: elevated IgG4; other organ inolvment; response to glucocorticoid therapy
How is AIP treated
Prednisone 40 mg/d for 4 weeks followed by taper dose of 5 mg/wk
Has been shown to be effective at inducing and maintaining remission in AIP
rituximab
True or false. Just like acute pancreatitis, amylase and lipase strikingly elevated in chronic pancreatitis
false.
Initial modality of choice in diagnosing chronic pancreatitis
Abdominal CT
Imaging findings in chronic pancreatitis
calcification, dilated ducts or an atrophic pancreas
Diagnostic test with best sensitivity and specificity in chronic pancreatitis
hormone stimulation using secretin. Abnormal results seen when 60% of pancretic exocrine function is lost
Cornerstone therapy of steatorrhea
enzyme therapy
How much of lipase should be taken during a meal
80,000-100,000 units
Can improve pain in chronic pancreatits
pregabalin
Ventral pancraetic anlage fails to migrate resulting to a ring of pancreatic tissue circling the duodenum
Annular pancreas
Radiographic findings of annular pancreas
symmetric dilation of the proximal duodenum with bulging of the recesses on either side of the annular band
Embyronic ventral and dorsal pancreatic anlagen fail to fuse so that pancreatic drainage is accomplished throuh the accessory papillar
pancreas divisum
Condition where amylase circulating the blood is in polymer form too large to be excreted by the kidney. There is elevated serum amylase and low urinary amylase.
Macroamylasemia
