Flashcards in 16. Pancreas: Acute, Chronic, and AI Pancreatitis Deck (86):
What is the annual incidence for acute pancreatitis?
4.9 to 35 per 100,000
What are the main causes of mortality from AP in the first two weeks?
SIRS: systemic inflammatory response syndrome
What is the definition of SIRS?
Two or more abnormalities in the temperature, HR, respiration, or WBC count NOT related to infection
What is the main cause of mortality from AP after the first two weeks?
Sepsis and its complications
What are the main causes of AP?
Intraductal papillary nucinous neoplasm and pancreatic cancer
What is the most common cause of AP in the world? (25-40% of all cases)
What % of people with gallstones develop pancreatitis?
What % of alcoholics develop pancreatitis? What % of cases in the US?
**usually after MANY years of alcohol abuse
What level of TGs is a RF for AP? What % of AP cases?
1-4% of AP cases
What is pancreas divisum?
Congenital condition where the dorsal and ventral drainage is separate and the major drainage is through the minor papilla
What % of people with pancreas divisum develop pancreatitis?
Less than 5% (not a major risk factor)
Why is risk for pancreatitis increased post-ERCP (Endoscopic retrograde cholangiopancreatography)
Pancreatic duct can be disrupted due to proximity to the bile duct
**pancreatitis in 3-5% of ERCPs w/o manometry
What are four mutations that can increase the risk for pancreatitis?
1. PRSS1 (Serine protease 1)
2. CFTR (cytic fibrosis transmembrane conductance regulator)
3. SPINK1 (serine protease inhibitor Kazal type 1)
4. CTRC (Chymotrypsin C)
How does alcohol act as an inciting event for AP?
1. Increased effect of CCK on activating TFs, NF-kB, and protein-1
2. Acetaldehyde and ox stress activate pancreatic stellate cells
3. Generation of acetalehyde and and fatty acid ethyl esters
4. Sensitization of acinar cells to premature activation of zymogens by CCK
How do gallstones act as an inciting event for AP
1. Reflux of bile into the pancreatic duct
2. Ampullary obstruction from stones or edema
How does hypertriglyceridemia act as an inciting event for AP?
Free fatty acid release by pancreatic lipase
How do genetics act as inciting events for AP?
Premature activation of pancreatic zymogens
- CTFR gene mutations, more concentrated and acidic pancreatic juice production -> ductal obstruction or altered acinar cell function
What are the main early acute changes in AP that all inciting events lead to?
1. Intraacinar activation of proteolytic enzymes
2. Microcirculatory injury
3. Leukocyte chemoattraction
4. Release of cytokines and oxidative stress
What does intraacinar activation of proteolytic enzymes involve?
1. Generation of large amounts of active trypsin within the pancreas
2. Vacuoles containing active trypsin rupture
3. Overwhelming of natural defense mechanisms
4. Pancreatic autodigestion from intrapancreatic release of active enzymes
What are the normal defense mechanisms that are overwhelmed in the setting of intraacinar activation of proteolytic enzymes?
1. Pancreatic secretory trypsin inhibitor
2. Autolysis of prematurely activated trypsin
3. Mesotrypsin and enzyme Y lysis of trypsin
4. Nonspecific antiproteases (A1AT, alpha2 macroglobulin)
What is involved in the microcirculatory injury seen in early acute changes in AP
1. Damage of vascular endothelium and pancreatic interstitium
2. Vasoconstriction, capillary stasis, ischemia, and decreased oxygen saturaiton
3. Increased vascular permeability and pancreatic gland swelling
4. Possible role of ischemia-reperfusion injury
What is involved in leukocyte chemoattraction seen as an early acute change in AP?
Complement activation and C5a release
What is involved in release of cytokines and oxidative stress as early acute changes in AP?
IL-1, 6, 8
Prostaglandins, PAF, leukotrienes
Proteolytic and lipolytic enzymes
Reactive oxygen metabolites
What are the components of the systemic response in AP?
2. Renal failure
3. Myocardial depression
4. Bacterial translocation from the gut
What are the clinical manifestations of AP?
Acute onset of persistent, severe epigastric abdominal pain
Pain radiating to back in 50% of cases
Nausea and vomiting in 90% of cases
No pain in 5-10% of cases
Ileus can be present (gut hypomotility)
What are the laboratory findings in AP?
1. Amylase elevated in 6-12 hours
2. Lipase elevated in 4-8 hours, peaks at 24
When does lipase return to normal after AP?
What are two inflammatory markers that will rise along with amylase and lipase in AP?
What is the best way to look for the MCC of AP?
Abdominal ultrasound: evaluate for gallstones in the gallbladder (cholelithiasis) and bile duct (choledocholithiasis)
**visualization can be obscured by bowel gas
What modality is good for detecting necrosis related to AP but NOT gallstones?
What has a higher sensitivity to early AP than CT, with a better visualization of the bile duct and pancreatic duct?
Diagnosis of AP required at least 2 of the following:
1. Constant epigastric or LUQ pain with radiation to the back or flanks
2. Serum amylase and/or lipase > 3 x the upper range of normal
3. Characteristic abdominal imaging findings
What % of people with AP have local or systemic complications?
What are the two main local complications or AP?
Acute peripancreatic fluid collection ( pseudocysts (>4wk)
Acute necrotic collection ( walled off necrosis (>4wk)
What are the main systemic complications of AP?
Organ failure--acute respiratory failure, shock, renal failure
What is the classification of AP?
Mild: absence of organ failure and local/systemic complications
Moderate: transient organ failure resolving in 48 hr and/or local or systemic complications w.o organ failure over 48 hr
Severe: Failure of one or more organs over 48 hr
What are the components of AP treatment?
1. Pain control
2. IV fluids
5. Cholecystectomy for gallstone AP
6. Endoscopic necrosectomy or surgery
7. Rectal indomethacin to prevent post-ERCP pancreatitis
8. Pancreatic stint
What is an acute peripancreatic fluid collection after 4 weeks?
What is aggressive IV hydration most beneficial in AP?
Early hydration in the first 12-24 hours
What is an acute necrotic collection called after 4 weeks?
What is preferred to normal saline for AP?
Walled off necrosis
Lactated Ringer's solution--less SIRS due to less bicarb
What type of nutrition is preferred in AP?
Enteral over parenteral
What should be preformed within 24 hr of admission for AP and acute cholangitis?
*not needed in most patients with gallstone pancreatitis with no evidence of ongoing biliary obstruction
What should be given after ERCP to prevent pancrreatitis?
What is the role of a pancreatic stint post-ERCP?
Allows the pancreas to drain and prevents inflammation from blocking the drainage
What are the etiologies for CP?
1. Constant alcohol abuse
2. Cigarette smoking
3. Ductal obstruction
4. Ampullary obstruction
What gene mutation causes hereditary acute pancreatitis, or recurrent AP in early childhood?
PRSS1 (serine protease 1)
What are the three gene variants assocaited with CP?
What gene variant is associated with hereditary chronic pancreatitis, with an autosomal dominant pattern of inheritance?
Hereditary pancreatitis from PRSS1 mutation causing CP has an increased risk for:
pancreatic cancer, beginning in the 50s
Where is tropical pancreatitis found? Who is affected?
**Cassava fruit implicated
What are two congenital causes of CP?
What is the pathogenesis of CP?
1. Progressive fibroinflammatory process resulting in permenant structural damage
2. Proteinaceous ductal plugs
5. Decreased antioxidants
What are the main differences between AP and CP?
AP painful, CP can be asymptomatic
Serum amylase and lipase tend to be normal in CP
CP is patchy, AP is more diffuse
What causes the proteinaceous ductal plugs that can cause CP? Result?
Increased pancreatic protein secretion
Plugs in ducts
Nidus for calcification
Stones in ducts
Duct scarring and obstruction
What is likely to perpetuate rater than initiate CP?
What are the main clinical manifestations of CP?
- Abdominal pain after eating, most continous later in course (no pain in 20-45% of patients)
- Pancreatic insufficiency
What are the two main components of pancreatic insufficiency seen with CP, starting with the one seen first?
1. Fat malabsorption: seen when over 90% of the pancreatic function is lost
2. Diabetes mellitus: late in disease
What is the presentation of fat malabsorption?
Steatorrhea: greasy, foul smelling stools
When is it more common to get diabetes mellitus as a consequence of CP?
Chronic, calcifying disease
Family hx of diabetes
What imaging modalities are used for CP?
Abdominal plain films--see pancreatic calcifications
Abdominal ultrasound, CT, MRI: calcifications, ductal dilation, enlargement of the pancreas, fluid collections
What imaging finding is pathopneumonic for CP?
Calcifications in the pancreas
What is DIRECT pancreatic function testing?
Stimulation of the pancreas with a meal (Lundh test) or horomones (secretin or CCK)
Duodenal fluid collected to quanitfy pancreatic secretory content (enzymes, bicarb)
What do indirect pancreatic function testing generally measure?
Consequences of pancreatic insufficiency
What is measured as INDIRECT pancreatic function tests?
1. Fecal elastase and chymotrypsin (both remain stabile in transit, but elastase more so) **
2. Serum trypsinogen: less sensitive and specific without ADVANCED exocrine insufficiency
3. Fecal fat
4. Secretin MRI
5. Pancreolauryl test
6. 13C breath test
How does the pancreolauryl test work (indirect pancreatic function test)?
Ingestion of fluorescein dilaurate with breakfast
Cleaved in proportion to amt of pancreatic cholesterol esterase
Measure the fluorescein excreted in the urin
How does the 13C breath test work (indirect pancreatic function test)?
Ingested 13C marked substances are hydrolyzed in proportion to the amt of pancreatic lipase-> released as 13CO2 by the lungs
Why is CP difficult to diagnose?
1. Laboratory studies and imaging are normal early
2. Pancreatic calcifications, steatorrhea, and diabetes mellitus are usually seen late in disease
3. Can be difficult to distinguish from pancreatic cancer
What is a ductal disruption that is usually asymptomatic, but can expand and become infected? (seen in 10% of CP patients)
What is the treatment of pseudocytes from CP?
What causes bile duct and/or duodenal obstruction in 5-10% of CP patients
Extrinsic comperssion from inflammation and fibrosis in the pancreatic head or pseudocyst
What is the treatment for bile duct and/or duodenal obstruction
Surgical or endoscopic psuedocyst drainage
How do you treat a pancreatic fistula that may result from CP?
ERCP for pancreatic stint placement
How do you treat splenic vein thrombosis that can result from CP?
What is the effect of a pseudoaneurysm (blood leakage from an artery into surrounding tissue) as a complication of CP?
Can affect blood vessels near the pancreas (splenic, hepatic, gastroduodenal)
What is the treatment for pseudoaneurysm?
Angiography with embolization
What are the effects of pancreatic enzyme supplimentation in the tx of CP?
1. May decrease pain by decreasing CCK release
2. Address steatorrhea by providing pancreatic lipase
What procedures can be done for the tx of CP?
1. Endoscopic or surgical decompression for patients with dilated pancreatic duct
2. Resection +/- islet cell transplant
AIP is the etiology of pancreatitis in less than __% of patients
In AIP, plasma cells are + for __ in tissue and there are elevated serum levels of ___ in some patients
What is the clinical presentation of AIP?
1. Pancreatic mass that mimic cancer
2. Mild abdominal pain +/- attacks of AP and CP
3. Pancreatic duct strictures (from IgG4 infiltration)
**usually presents with a mass and not pain
What is the criteria for type 1 AIP?
elevated Serologies (IgG4)
Response to glucocorticoid Therapy
What is characteristic of the histology seen in type I AIP?
Lymphoplasmacytic sclerosing pancreatitis
More than 10 IgG4 + cells with at least 2 of:
1. Periductal lymphoplasmacytic infiltrate
2. Obliterative phlebitis
3. Acinar fibrosis
What is seen on imaging with Type I AIP?
Diffusely enlarged pancreas with featureless borders
Delayed enhancement with or without capsule-like rim
What is elevated on serology with Type I AIP?
What is characteristic of Type 2 AIP?
Histologically confirmed idiopathic duct centric pancreatitis, often with granulocytic lesions without IgG4 + cells or systemic involvement
**unlikely to relapse
**likely to be assoicated with IBD