Module 2: GI: Pancreatic Lesions Flashcards
Moving onto the Pancreatic lesions, first lets start with the inflammatory lesions. What is the etiology for acute pancreatitis?
Gallstones and alcohol are the most common causes
What is the pathogenesis for acute pancreatitis?
Pancreatic Injury — release of tyrpsin then amylase and lipase — released FAs combine with Ca2+ —- saponification (chalky white deposits on surface of pancreas )
- –can lead to hypocalcemia and tetany
- -Liquefactive necrosis of the exocrine pancreas
What is the presentation for acute pancreatitis?
Excruciating and sudden onset epigastric pain
Fever
Nause
Vomiting
Explain the elevation in the enzymes with acute pancreatitis?
Amylase elevated initially
—first 24 hours is more sensitive
Lipase elevated 72-96 hours
–more specific
What is the definitive diagnosis of acute pancreatitis?
CT/MRI
- -fat in the peripancreatic space and liquefactive in the exocrine pancreas also called pancreatic acini necrosis
- -spares the islets of langerhans
what is the most important prognostic factor for acute pancreatitis?
Decreased calcium levels
–lower the worse the prognosis
What are complications of acute pancreatitis?
Septic Shock (recurrent bacterial infections)
Hypovolemic Shock
Acute tubular necrosis
Hypocalcemia
–cardiac arrhythmias and tetany
ARDS
–enzymes damage lung (diffuse alveolar damage due to damage to the type II pneumocytes)
DIC
–Enzymes activate both clotting pathways
In acute pancreatitis is the endocrine or exocrine pancreas destroyed?
Exocrine pancreas destroyed first
- -islets spread
- -liquefactive necrosis
- -fat necrosis
Next moving onto chronic pancreatitis, what is the etiology?
Chronic alcoholism most common cause
–recurrent acute pancreatitis
Cystic Fibrosis (due to mucus plugs)
Malabsorption: intraluminal hydrolysis of
-fat, fat soluble vitamins, and B12 is defective
In chronic pancreatitis is the endocrine or exocrine pancreas destroyed?
Starts in exocrine and affects islets
then progresses to endocrine
What investigations are done for chronic pancreatitis?
CT scan most accurate
–dystrophic calcification and fibrosis of the pancreas
What is the most important prognostic indicator for chronic pancreatitis?
Dystrophic Calcification with low Calcium
–causes malabsorption of Vit D
What are complications of chronic pancreatitis?
- Malabsorption
- DM type I (insulin for life)
- Pancreatic Adenocarcinoma
- Pancreatic pseudocysts (lined by fibrous scar/granulation tissue, due to atrophy of the epithelium) (susceptible to infection) (seen on histology)
Moving on to Autoimmune pancreatitis (lymphoplasmacytic sclerosing pancreatitis/ duct-destructive pancreatitis). There are two types, describe type I
Type 1: Lymphoplasmacytic infiltrate centered around large and medium sized interlobular duct
- -periductal and perivenular fibrosis
- -obliterative phlebitis (arteries are spared)
- -Increased IgG4 plasma cells
- -male predominance
Describe type 2 autoimmune pancreatitis
Type 2: Lymphoplasmacytic Infiltrate centered around ducts
- -granulocytic epithelial lesions with partial/complete duct obstruction/obliteration
- -Ig4 plasma cells are usually absent
- -affects genders equally