Gallbladder & Biliary Tree Pathophysiology Flashcards Preview

DEMS: Unit 1 > Gallbladder & Biliary Tree Pathophysiology > Flashcards

Flashcards in Gallbladder & Biliary Tree Pathophysiology Deck (26):
1

Characteristics of bile

  • yellow liquid
  • amphopathic properties
  • contributes to excretion of cholesterol, copper, meds & lipid digestion @ small bowel
  • contents:
    • water
    • bile acids
    • cholesterol
    • phospholipids
    • lecithin
    • electrolyes

2

Normal anatomy of biliary tract

  • Bile synthesized @ liver ==> cannaliculi ==> intrahepatic ducts ==> R & L hepatic ducts ==> common hepatic duct 
  • @ fasting: sphincter of Oddi closed & gallbladder/bile duct peristalsis imhibited ==> bile flows from liver to cystic ducto ==> gallbladder for storage
  • @ fed: increased CCK + vagal tone ==> peristalsis ==> transport of bile to duodenum

3

Causes of gallstones

  • bile composition = too much cholesterol, too little water or both
  • supersaturation of bile w/cholesterol ==> cholesterol crystals ==> choleliths
  • pathogenic factors:
    • gallblader/dile duct stasis
    • hereditary mutations @ cholesterol structure
    • inflammation @ gallblader

4

Types of choleliths

  • cholesterol
    • mainly cholesterol + bile acids, phospholipis, lecithin
    • white/yellow color + greasy/soft
  • pigment stones
    • mainly calcium bilirubinate salts + mucin nidus
    • occur when increased bilirubin in bile
      • e.g. hemolytic states (sickle cell)
    • black and hard

5

Risk factors for gallstones

  • cholesterol
    • mechanisms: cholesterol mutations, bile acid hypersecretion, gallblader stasis
    • risk factors:
      • obesity
      • rapid weight gain/loss
      • female
      • >30yo
      • Latin American/Native American 
      • estrogen/contraceptive use
  • Pigment
    • hemolytic state: e.g. sickle cell
    • Asian

6

Dx of gallstones

  • Dx: ultrasound
    • can detect gallstones or cholecystitis (>90%)
    • also sensitive to determine any ductal dilation
    • more difficulty detecting bile duct stones (50%)
  • CT may be considered if cause of pain is unclear/other orgas need to be evaluated

7

Tx of gallstones

  • Endoscopic retrograde cholangiopancreatography (ERCP)
    • can remove stones, place stents
    • small risk of pancreatitis

8

Characteristics of biliary colic

  • stones travel downstream and partially obstruct gallblader neck, cystic duct, or common bile duct
  • biliary colic = 
    • after meals (particularly fatty ones)
    • dull or crampy pain @ epigastrium/RUQ
    • occurs w/in hour of eating and last 3-5 hours and then resolve spontaneously

9

Mechanism/cause of cholecystitis

  • gallstone lodges @ cystic duct & becomes impacted
  • bacterial superinfection of gallbladder lumen ==> acute (calculous) cholecystitis = severe inflammation and/or ischemia of gallbladder

10

Presentation of acute cholecystitis

  • severe pain @ RUQ; radiating to right flank or shoulder
  • nauseau 
  • fever
  • TTP (deep) of RUQ
  • Murphy's sign: deep palpation on exhalation ==> pt. stops exhaling suddenly

11

Management of acute cholecystitis

–NPO (gallbladder rest)
–IV hydration
–IV antibiotics
–Surgical removal of the gallbladder (cholecystectomy)  when stable
–Percutaneous drainage of gallbadder in patients too ill for surgery
 

12

Mechanism & Management of acalculous cholecystitis

  • Usually caused by ischemia of gallbladder
    • Risk factors = sepsis, recent surgery, trauma/burns, hypotension
    • Vasculitis 
  • Symptoms, disease otherwise similar to ACC
  • Treatment: drainage of gallbladder or cholecystectomy
     

13

Mechanism/cause of choledocholithiasis

  • cause: stone obstructs the common bile duct
    • majority stones migrate from gallbladder
    • ~10% form de novo @ CND

14

Presentation of choledocholithiasis

•Jaundice, dark urine, and abdominal pain
•May also cause acute pancreatitis 
 

15

Diagnosis of choledocholithiasis

  • Liver chemistries/CBC
    • elevated conjugated bilirubin
    • elevated serum transaminases
    • elevated alkaline phosphatase
    • elevated cholesterol
    • if pancreatitis ==>
      • raised serum lipase/amylase
      • elevated INR (decreased vit K absorption)
  • –Ultrasound
  • –MRCP or ERCP
     

16

Mechanism/cause of ascending cholangitis

•Bacterial infection of bile duct
•Almost always a complication of choledocholithiasis
 

17

Presentation of ascending cholangitis

  • Symptoms = Charcot’s triad
    • Fever
    • RUQ pain
    • Jaundice
  • Sepsis or death may occur if untreated
     

18

Reynold's pentad

Charcot’s triad + hypotension + altered mental status

19

Management/Dx of ascending cholangitis

  • Initial management
    • Admit to hospital
    • NPO
    • Broad spectrum IV abx
    • IV fluids
  • Diagnosis:
    • History, labs, US are usually suggestive
  • Definitive diagnosis and management
    • Urgent ERCP!
       

20

Characteristics of biliary stricutres (general)

  • Fixed narrowing or blockage of bile duct
    • benign = caused by fibrosis/scarring secondary to chronic inflammation
    • malignant = caused by cancer
  • Intra- or extrahepatic
  • Intrinsic or extrinsic
  • Symptoms are more chronic and persistent than stones
     

21

Benign causes of biliary stricture

  • Iatrogenic - surgery, radiation
  • Primary sclerosing cholangitis (PSC)
  • Chronic pancreatitis
  • Chronic choledocholithiasis
  • Autoimmune pancreatitis
     

22

Malignant causes of biliary stricture

–Pancreatic cancer
–Cholangiocarcinoma
–Gallbladder cancer
–Ampullary cancer
 

23

Presentation of biliary stricture

  • •RUQ pain
  • •Cholestasis:
    • •Jaundice
    • •Dark urine (choluria)
    • •Acholic stools
    • •pruritus
  • •LFTs elevated in cholestatic pattern:
    • •Alk phos/GGT, bilirubin >> ALT/AST
       

24

Management of biliary stricture

–ERCP with dilation or stenting
–Biopsy to rule out malignancy, if applicable
–Surgery if refractory or malignant
 

25

Characteristics/presentation of sphincter of oddi dysfxn

  • •Motility disorder of Sphincter of Oddi
  • •Typically intermittent
  • •Symptoms, labs, imaging may mimic choledocholithiasis
  • •Presentation
    • –Recurrent RUQ pain
    • –Dynamically elevated ALT/AST/alk phos
    • –Dilated bile duct on US

26

Dx/Tx of sphincter of Oddi dysfxn

  • Diagnosis
    • ERCP with sphincter of Oddi manometry
  • Tx
    • biliary sphincterotomy