Biliary Tract Flashcards
List the components of the biliary tract.
Intrahepatic ducts combine to form the left and right hepatic ducts -> common hepatic duct
Gallbladder -> cystic duct
Cyst duct + hepatic duct -> common bile duct -> Ampulla of Vater
What is the name of the node in Calot’s triangle?
Calot’s node
What are the small ducts that drain bile directly into the gallbladder from the liver?
Ducts of Luschka
Which artery is susceptible to injury during cholecystectomy?
Right hepatic artery, because of its proximity to the cystic artery and Calot’s traingle
Where is the infundibulum of the gallbladder?
Near the cystic duct
Where is the fundus of the gallbladder?
At the end of the gallbladder
What are the boundaries of the triangle of Calot?
- Cystic duct (inferior)
- Common hepatic duct (medial)
- Cystic artery (superior)
What is the source of alkaline phosphatase?
Bile duct epithelium; expect elevation in bile duct obstruction
What is in bile?
Cholesterol
Lecitihin (phospholipid)
Bile acids
Bilirubin
What does bile do?
Emulsifies fats
What is the enterohepatic circulation?
Circulation of bile acids form liver to gut and back to th eliver
Where are most of the bile acids absorbed?
In the terminal ileum
What stimulates gallbladder emptying?
Cholecystokinin and vagal input
What is the source of cholecystokinin?
Duodenal mucosal cells
What are the actions of cholecystokinin?
Gallbladder emptying
Opening of ampulla of Vater
Slowing of gastric emptying
Pancreas acinar cell growth and release of exocrine products
At what level of serum total bilirubin does one start to get jaundiced?
2.5
Classically, what is thought to be the anatomic location where one first finds evidence of jaundice and why?
Under the tongue (UV light breaks down bilirubin at other sites)
What are the signs and symptoms of obstructive jaundice?
Jaundice Dark urine Clay-colored stools (acholic stools) Pruritis (itching) Loss of appetite Nausea
What causes the itching in obstructive jaundice?
Bile salts in the dermis (not bilirubin!)
Define cholelithiasis.
Gallstones in the gallbladder
Define choledocholithiasis.
Gallstone in common bile duct
Define cholecystitis
Inflammation of the gallbladder
Define cholangitis.
Infection of biliary tract
Define cholangiocarinoma.
Adenocarcinoma of bile ducts
Define Klatskin’s tumor.
Cholangiocarinoma of bile duct at the junction of the right and left hepatic ducts
Define biliary colic.
Pain from gallstones, usually from a stone at the cystic duct
Pain is located in the RUQ, epigastrium, or right subscapular region of the back
Usually lasts minutes to hours but eventually goes away; often postprandial, especially after fatty foods
Define biloma.
Intraperitoneal bile fluid collection
Define choledochojejunostomy
Anastomosis between the common bile duct and jejunum
Define hepaticojejunostomy
Anastomosis of hepatic ducts or common hepatic duct to jejunum
What is the initial diagnostic study of choice for evaluation fo the biliary tract/gallbladder/cholelithiasis?
U/S
Define ERCP.
Endoscopic Retrograde Cholangio-Pancreatography
Define PTC.
Percutaneous Transhepatic Cholangiogram
Define IOC.
IntraOperative Cholangiogram (done laparoscopically or open to rule out choledocholithiasis)
What is a HIDA/PRIDA scan?
Radioisotope study; isotope concentrated in liver and secreted into bile; will demonstrate cholecystitis, bile leak, or CBD obstruction
How does the HIDA scan reveal cholecystitis?
Non-opacification of the gallbladder from obstruction of the cystic duct
What is a cholecystectomy?
Removal of the gallbladder laparoscopically or through a standard Kocher incision
What is a sphincterotomy?
Cut through the sphincter of Oddi to allow passage of gallstones from the common bile duct; most often done at ERCP
How should post-operative biloma be treated after a lap chole?
Percutaneous drain bile collection
ERCP with placement of biliary stent past leak (usually cystic duct remnant leak)
What is the treatment of major CBD injury after a lap chole?
Choledochojejunostomy
What is obstructive jaundice?
Jaundice (hyperbilirubinemia >2.5) from obstruction of bile flow to the duodenum
DDx - proximal bile duct obstruction (11)
Cholanigiocarcinoma Lymphadenopathy Metastatic tumor Gallbladder carcinoma Sclerosing cholangitis Gallstones Tumor embolus Parasites Post-surgical stricture Hepatoma Benign bile duct tumor
DDx - distal bile duct obstruction (11)
Choledocholithiasis (gallstones) Pancreatic carcinoma Pancreatitis Ampullary carcinoma LAD Pseudocyst Post-surgical stricture Ampulla of Vater dysfunction/stricture Lymphoma Benign bile duct tumor Parasites
Initial study of choice for obstructive jaundice?
U/S
What lab results are associated with obstructive jaundice?
Elevated alk phos
Elevated bilirubin with or without elevated LFTs
Incidence of cholelithiasis?
~10% of the US population will develop gallstones
Classic 4 risk factors for cholelithiasis?
Female
Fat
Forty
Fertile (multiparity)
What are the types of gallstones?
- Cholesterol stones (75%)
2. Pigment stones (25%)
What are the types of pigmented stones?
- Black stones (contain calcium bilirubinate)
2. Brown stones (assc. with biliary tract infection)
What are the causes of black-pigmented stones?
Cirrhosis
Hemolysis
What is the pathogenesis of cholesterol stones?
Secretion of bile supersaturated with cholesterol (relatively decreased amounts of lecithin and bile salts); then, cholesterol precipitates out and forms solid crystals, then gallstones
Signs and symptoms of cholelithiasis?
Symptoms of biliary colic, cholangitis, choledocholithiasis, gallstone pancreatitis
Why is biliary colic a misnomer?
Symptoms usually last for hours
What percentage of patients with gallstones are asymptomatic?
80%
What is the thought to cause biliary colic?
Gallbladder contraction against a stone temporarily at the gallbladder/cystic duct junction; a stone in the cystic duct; or a stone passing through the cystic duct
What are the 5 major complications of gallstones?
Acute cholecystitis Choledocholithiasis Gallstone pancreatitis Gallstone ileus Cholangitis
How is cholelithiasis diagnosed?
H&P
U/S
How often does U/S detect choledocholithiasis?
~33% (not a very good study for choledocholithiasis)
How are symptomatic or complicated cases of cholelithiasis treated?
By cholecystectomy
What are the possible complications of a lap chole?
Common bile duct injury
Right hepatic duct/artery injury
Cystic duct leak
Biloma (collection of bile)
What are the indications for cholecystectomy in the asymptomatic patient?
Sickle-cell disease
Calcified gallbladder (porcelain gallbladder)
Patient is a child
Management of choledocholithiasis?
ERCP with papillotomy and basket/balloon retrieval of stones (pre- or post-operatively)
Laparoscopic transcystic duct or trans common bile duct retrieval
Open common bile duct exploration
What medication may dissolve a cholesterol gallstone?
Chenodeoxycholic acid
Ursodeoxycholic acid
But, if meds are stopped, gallstones often recur
What is the major feared complication of ERCP?
Pancreatitis
What is the pathogenesis of acute cholecystitis?
Obstruction of cystic duct leads to inflammation of the gallbladder
Causes of acute cholecystitis?
~95% result from calculi
~5% from acalculous obstruction
Risk factors for acute cholecystitis?
Gallstones
What are the signs and symptoms of acute cholecystitis?
Unrelenting RUQ pain or tenderness Fever N/V Painful palpable gallbladder in 33% Positive Murphy's sign Right subscapular pain (referred) Epigastric discomfort (referred)
What is Murphy’s sign?
Acute pain and inspiratory arrest elicited by palpation of the RUQ during inspiration
What are the complications of acute cholecystitis?
Abscess Perforation Choledocholithiasis Cholecysteneteric fistula formation Gallstone ileus
What lab results are associated with acute cholecystitis?
Increased WBC
May have slight elevation in alk phos, LFTs, amylase, total bilirubin
Dx test of choice for acute cholecystitis?
U/S
Signs of acute cholecystitis on U/S?
Thickened gallbladder wall (>3 mm) Pericholecystic fluid Distended gallbladder Gallstones present/cystic duct stone Sonographic Murphy's sign
What is the difference between acute cholecystitis and biliary colic?
Biliary colic has temporary pain
Acute cholecystitis has pain that does not resolve, usually with elevated WBCs, fever, and signs of acute inflammation on U/S
What is the treatment of acute cholecystitis?
IV fluid
ABX
Early cholecystectomy
What is acute acalculous cholecystitis?
Acute cholecystitis without evidence of stones
What is the pathogenesis of acute acalculous cholecystitis?
Believed to result from sludge and gallbladder disuse and biliary stasis, perhaps secondary to absence of cholecystokinin stimulation (decreased gallbladder contraction)
What are the risk factors for acute acalculous cholecystitis?
Prolonged fasting TPN Trauma Multiple transfusions Dehydration Prolonged post-op or ICU setting
What are the diagnostic tests of choice for acute acalculous cholecystitis?
U/S (sludge and inflammation usually present)
HIDA scan
What are the findings of acalculous cholecystitis on HIDA scan?
Non-filling of the gallbladde
What is the management of acute acalculous cholecystitis?
Cholecystectomy or cholecystectomy tube if unstable (placed percutaneously by radiology or open surgery)
What is cholangitis?
Bacterial infection of the biliary tract from obstruction (either partial or complete); potentially life-threatening
What are the common causes of cholangitis?
Choledocholithiasis
Stricture (usually post-operative)
Neoplasm (usually ampullary carcinoma)
Extrinsic compression (pancreatic pseudocyst/pancreatitis)
Instrumentation of the bile ducts (PTC/ERCP)
Biliary stent
What is the most common cause of cholangitis?
Choledocholithiasis
Signs and symptoms of cholangitis?
Fever/chills RUQ pain Jaundice (Charcot's triad) \+Mental status changes and shock = Reynold's pentad
Which organisms are most commonly isolated with cholangitis?
GN organisms (E. coli, Klebsiella, Pseudomonas, Enterobacter, Proteus, Serratia)
Dx test of choice for cholangitis?
U/S and contrast study (ERCP or IOC) after the patient has “cooled off” with IV ABX
What is suppurative cholangitis?
Severe infection with sepsis
Management of non-suppurative cholangitis?
IVF and ABX, with definitive treatment later (lap chole +/- ERCP)
Management of suppurative cholangitis?
IVF
ABX
Decompression (ERCP with papillotomy, PTC with cath drainage, lap with T-tube placement)
What is sclerosing cholangitis?
Multiple inflammatory fibrous thickenings of bile duct walls resulting in biliary strictures
What is the natural history of sclerosing cholangitis?
Progressive obstruction possibly leading to cirrhosis and liver failure; 10% will develop cholangiocarcinoma
Major risk factor for sclerosing cholangitis?
IBD (UC most common -> 66%)
What are the signs and symptoms of sclerosing cholangitis?
Same as those for obstructive jaundice (many are asymptomatic as well)
How is sclerosing cholangitis diagnosed?
Elevated alk phos
PTC or ERCP revealing “beads on a string” appearance on contrast study
What are the management options for sclerosing cholangitis?
Hepatoenteric anastomosis (if primarily extrahepatic ducts are involved) and resection of extrahepatic bile ducts because of the risk of cholangiocarcinoma
Transplant (if primarily intrahepatic disease or cirrhosis)
Endoscopic balloon dilations
What is gallstone ileus?
SBO from a large gallstone (>2.5 cm) that has eroded through the gallbladder and into the duodenum/small bowel
Classic site of obstruction in gallstone ileus?
Ileocecal valve (but may cause obstruction in the duodenum, sigmoid colon)
Classic findings of gallstone ileus on imaging?
Air in the hepatic bile ducts
SBO with air fluid levels
Gallstone in ileocecal valve
Who is at risk for gallstone ileus?
Most common in women >70 y/o
Signs and symptoms of gallstone ileus?
SBO symptoms (distention, vomiting, hypovolemia, RUQ pain)
Gallstone ileus causes what percentage of cases of SBO?
<1%
Dx test of choice for gallstone ileus?
Abdominal X-ray occasionally reveals radiopaque gallstone in the bowel; 40% of patients show air in the biliary tract, small bowel distention, and air fluid levels secondary to ileus
UGI: used if dx is in question, will show cholecystenteric fistula and the obstruction
Abdominal CT: air in biliary tract, SBO +/- gallstone in intestine
Management of gallstone ileus?
Enterotomy with removal of the stony +/- interval cholecystectomy (interval delayed)
What is carcinoma of the gallbladder?
Malignant neoplasm arising in the gallbladder, vast majority (90%) are adenocarcinoma
Risk factors for carcinoma of the gallbladder?
Gallstones
Porcelain gallbladder
Cholecystenteric fistula
What percentage of patients with a porcelain gallbladder will have gallbladder cancer?
~50% (20-60%)
Incidence of gallbladder carcinoma?
~1% of all gallbladder specimens
Symptoms of gallbladder cancer?
Biliary colic
Weight loss
Anorexia
Many asymptomatic until late
May present as acute cholecystitis
Signs of gallbladder cancer?
Jaundice (from invasion of the common duct or compression by involved pericholedochal lymph nodes), RUQ mass, palpable gallbladder (advanced gisease)
Dx tests of choice for gallbladder cancer?
U/S
Abdominal CT scan
ERCP
Route of spread of gallbladder cancer?
Contiguous spread to the liver is most common
Management of gallbladder cancer if confined to mucosa?
Cholecystectomy
Management of gallbladder cancer if confined to muscularis/serosa?
Radical cholecystectomy (chole + wedge resection of overlying liver, and LN dissection +/- chemo/XRT)
What is the main complication of a lap chole for gallbladder cancer?
Trocar site tumor implants (if known preoperatively, perform open chole)
Prognosis for gallbladder cancer?
Dismal overall: <5% 5-year, as most are unresectable at diagnosis
T1 with cholecystectomy: 95% 5-year
What is cholangiocarcinoma?
Malignancy of the extrahepatic or intrahepatic ducts (primary bile duct cancer)
What is the histology of cholangiocarinoma?
Almost all are adenocarcinoms
Average age at dx - cholangiocarcinoma?
~65 years (M=F)
Most common location of cholangiocarcinoma?
Proximal bile duct
Risk factors for cholangiocarcinoma?
Choledochal cysts UC Thorotrast contrast dye (used in 1950s) Sclerosing cholangitis Liver flukes (clonorchiasis) Toxin exposures (Agent orange, etc.)
Dx tests of choice for cholangiocarinoma?
U/S
CT
ERCP/PTC with biopsy/brushings for cytology
MRCP (MRI with visualization of pancreatic and bile ducts)
Management of proximal bile duct cholangiocarinoma?
Resection with Roux-en-Y hepaticojejunostomy (anastomose bile ducts to jejunum) +/- unilateral hepatic lobectomy
Management of distal common bile duct cholangiocarcinoma?
Whipple procedure
Cause of calcified gallbladder?
Chronic cholelithiasis/cholecystitis with calcified scar tissue in gallbladder wall
What is hydrops of the gallbladder?
Complete obstruction of the cystic duct by a gallstone, with filling of the gallbladder with fluid (not bile) form the gallbladder mucosa
What is Gilbert’s syndrome?
Inborn error in liver bilirubin uptake and glucuronyl transferase resulting in hyperbilirubinemia
What is Courvoisier’s gallbladder?
Palpable, non-tender gallbladder associated with cancer of the head of the pancreas; able to distend because it has not been “scarred down” by gallstones
What is Mirizzi’s syndrome?
Common hepatic duct obstruction as a result of extrinsic compression from a gallstone impacted in the cystic duct
