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Pathology 18 p882-888
The Biliary Tract
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95% of disease from cholelithiasis
Congenital Anomalies
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Congenitally absent, duplication, bilobed, aberrant locations (mostly in liver), folded fundus
(most common) creates phrygian cap, agenesis, hypoplasia
Disorders of the Gallbladder
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Cholelithiasis (gallstones) = >80% silent
o Cholesterol stones (>50% of cholesterol monohydrate) and pigement stones (bilirubin
calcium salts)
o Prevalence and Risk Factors:
 Cholesterol stones > in West
 75% in Native Americans
 Risk increases with age, women > men, metabolic syndrome, obesity
o Hypersecretion of biliary cholesterol
 Estrogen (contraceptives and pregnancy) and colifibrate -> high HMGcoA reductase activity
 Gallbladder stasis
 ABCG5 and ABG2 variant (D19H) increases risk
o Can lower with statins
 Pigment stones > non-West
 Bacterial and parasitic infections
 Gallbladder stasis
o Pathogenesis:
 Cholesterol stones -> supersaturation of cholesterol, hypomotility of gallbladder,
accelerated cholesterol nucleation, hypersecretion of mucus
 Pigment stones -> hemolytic syndromes , ileal dysfuction, bacterial
contamination (E. coli, Ascaris lumbricoides, O. sinesis)
o Morphology:
 Pure cholesterol stones -> pale yellow, round, hard surface, exclusively in
gallbladder
 Multiple stones often
 Stones composed largely of cholesterol are radiolucent; sufficient
calcium carbonate in 10-20% renders them radiopaque
 Pigment stones -> black are in gallbladder (many and crumble to touch), brown
in infected intra/extrahepatic ducts (soft, greasy with calcium soaps)
 50-75% of black stones are radiopaque; brown stons are radiolucent
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 Mucin glycoproteins in all stones
o Clinical:
 Asymptomatic but is symptoms = colicky biliary pain
 Cholecustitis, empyema, perforation, fistulas, cholangitis (inflammation of
biliary tree), cholestasis, pancreatitis
 Smaller more dangerous
 Gallstone ileus = Bouveret’s syndrome
 Increased risk for carcinoma
Cholecystitis = almost always with gallstones
o Acute Cholecystitis = acute inflammation precipitate 90% b obstruction of neck/cystic
duct, most common for emergency cholecystectomy
 Pathogenesis:
 Calculous cholecystitis -> chemical irritation (toxic lysolecithins and
prostaglandins) and inflammation of obstructed gallbladder (no
bacterial infection initially)
o Frequent in diabetic patients
 Acalculous cholecystitis -> ischemia of cystic artery; risk factors include
sepsis, immunosuppression, major trauma/burns, DM, and infections
o In hospitalized patients
 Morphology:
 Large gallbladder with fibrin layers
 Empyema of gallbladder (exudate is pure pus)
 Gangrenous cholecystitis (green-black necrotic organ)
 Clostridia and coliform invasion -> emphysematous cholecystitis
 Clinical:
 RUQ or epigastric pain, fever, anorexia, tachycardia, sweating, nausea
vomiting
 Acute calculous cholecystitis may appear suddenly (acute surgical
emergency) or mildly (subsides)
 Acute acalculous cholecystitis -> no symptoms referable to gallbladder
o Gangrene nd perforation higher
o Rarely from bacteria (Salmonella typhi and staphylococci)
o Chronic Cholecystitis = cholelithiasis in > 90%, supersaturation of bile (E. coli and
enterococci cultured in 1/3)
 Biliary colic or RUQ pain, epigastric distress
 Morphology:
 Adhesions from preexistent inflammation
 Inflammation variable along with fibrosis
 Outpouching of muscosal epithelium (Rokitansky-Aschoff sinuses)
 Porcelain gallbladder from dystrophic calcification (increased incidence
of cancer)
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Xanthogranulomatous cholecystitis from very thick wall, shrunken,
nodular, inflamed gallbladder
Hydrops of the gallbladder = atrophic obstructed gallbladder with only
clear secretions
Clinical:
 Recurrent attacks (steady or colicky pain)
 Nausea, vomiting, intolerance for fatty foods
 Perforation, cholangitis, rupture, fistula, or cancer are complications
Disorders of the Extrahepatic Bile Ducts
o Choledocholithiasis and Ascending Cholangitis = presence of stones withinthe bile ducts
of biliary tree (higher in Asia; pigmented) and bacterial infection of bile ducts
(obstruction)
 Bacteria enter through sphincter of Oddi
 Ascending cholangitis – infection of intrahepatic biliary radicles
 Enteric gram-negative aerobes (E. coli, klebsiella, interococcus,
Enterobacter)
 Fever, chills, abdominal pain, jaundice
 Suppurative cholangitis (severe) -> sepsis
o Biliary atresia = complete/partial obstruction of lumen of extrahepatic biliary tree within
first 3 months
 Most frequent cause of death from liver disease in early childhood
 Pathogenesis:
 Fetal form – 20%, with anomalies (malrotation of ab viscera, interrupted
IVC, polysplenia, CHD)
 Perinatal form – normal tree destroyed after birth, viral
infection/autoimmunity (reovirus, rotavirus, CMV)
 Morphology:
 Inflammation and fibrosing duct
 Liver cirrhosis within 3-6 months
 Limited to common duct (type 1) or hepatic bile duct (type II) may be
correctable (Kasai procedure)
 Type III -> obstruction at or above porta hepatis (noncorrectable)
 Clinical:
 Neonatal cholestasis, acholic stools
 Liver transplantation with bile ducts otherwise death within 2 years
o Choledochal cysts = congenital dilations of common bile duct
 Children <10, jaundice, recurrent ab pain (colic)
 With cystic dilation of intrabepatic biliary tree = Caroli disease
 Female > male
 Predispose to stone formation, stenosis/stricture, pancreatitis, obstruction
 Bile duct carcinoma risk high in older