Pathology of Diseases of the Gall Bladder and Biliary Tract Flashcards
What is biliary atresia?
failure to form or early destruction of extrahepatic biliary tree (bile ducts outside of the liver) leading to biliary obstruction within the first 2 months of life.
*remember atresia= failure to form lumen of a tube.
How does biliary atresia present?
with jaundice (due to conjugated bilirubin leaking into blood) and progresses to cirrhosis (from bilirubin backing up into the liver causing damage) in babies.
What is cholelithiasis (gallstones)?
solid round stones in the gallbladder due to precipitation of cholesterol (cholesterol stones) or bilirubin (bilirubin stones) in bile.
What causes cholelithiasis (gallstones)?
supersaturation of cholesterol or bilirubin, decreased phospholipids (lecithin, which helps to solubilize cholesterol) or bile acids (normally increase solubility also), or stasis (will increase bacterial growth which deconjugate bilirubin).
*So if a patient is taking a bile acid lowering agent like cholestyramine for cholesterol, this can increase the risk of gallstones.
What are the common types of stones in the West?
cholesterol stones (yellow) and are radiolucent (can't see them on X-ray). *If they have enough calcium carbonate this will make them radioopaque.
What are the risk factors for CHOLESTEROL stones?
- age 40
- estrogen (female gender, obesity, oral contraceptives) which increases HMG Co-A reductase and thus increased cholesterol synthesis.
- clofibrate (increases HMG Co-A reductase)
- Native American ethnicity
- Crohn’s disease
- cirrhosis
Will bilirubin stones show up on x-ray?
YES because they are pigmented and radiopaque.
What are the risk factors for BILIRUBIN stones?
- extravascular hemolysis (increased unconjugated bilirubin in bile)
- biliary tract infection (E. coli, Ascaris lumbricoides, Clonorchis sinensis).
- look like black BBs (if sterile gallbladder) or brown BBs (in infected gallbladder).
Are gallstones (cholelithiasis) usually symptomatic?
NO but there are 5 complications that can result from them:
- biliary oclic
- acute and chronic cholecystitis
- ascending cholangitis
- gallstone ileus
- gallbladder cancer
* if symptomatic, look for CHARCOT’S TRIAD= RUQ pain, fever, and jaundice.
What is biliary colic?
waxing and waning right upper quadrant pain due to the gallbladder contracting against a stone lodged in the cystic duct.
*symptoms are relieved if the stone passes.
Remember, what can common bile duct obstruction cause?
acute pancreatitis or obstructive jaundice.
What is acute cholecystitis?
acute inflammation of the gallbladder wall due to an impacted stone in the cystic duct causing dilation of the gallbladder, which will place pressure on the surrounding vasculature and thus ischemia, bacterial overgrowth (E. coli), and inflammation.
- may see empyema (lumen of gallbladder filled with pus).
- May also have ACALCULOUS CHOLECYSTITIS (inflammation without a stone) due to biliary surgery, gas producing organisms like clostridium causing gas pockets in the gallbladder, trauma, burns, hyperalimentation, or postpartum state.
** How does acute cholecystitis present clinically?
with right upper quadrant pain, often RADIATING to the RIGHT SCAPULA, fever with increased WBC, nausea, vomiting, and increased serum alkaline phosphatase (from duct damage).
*risk of rupture if left untreated!
What is chronic cholecystitis?
chronic inflammation of the gallbladder due to chemical irritation from longstanding cholelithiasis, with or without superimposed bouts of acute cholecystitis.
** What is a hallmark of chronic cholecystitis?
- Rokitansky-Aschoff sinus= herniation (outpouchings) of gallbladder mucosal epithelium into the muscular wall.
- Porcelain gallbladder (looks like a light bulb on X-ray) is a late complication (increased risk of carcinoma)= shrunken, hard gallbladder due to chronic inflammation, fibrosis, and dystrophic calcification (remember this is calcification deposition with NORMAL CALCIUM levels in the blood). Contrast that with metastatic calcification which is calcium deposition with hypercalcemia.
