Gallbladder & Biliary
Pathology

• Definition — solid concretions in the gallbladder, often asymptomatic
• Epidemiology
  • Prevalence ↑ with age, female sex, obesity, pregnancy
  • Native American Pima/Navajo have higher cholesterol stone risk
• Clinical presentation
  • Biliary colic: intermittent RUQ pain, often postprandial
  • Asymptomatic in majority (~80%)
• Diagnosis
  • Ultrasound (U/S): first-line, sensitivity >95%
  • Most stones are radiolucent (not seen on plain X-ray)
• Complications
  • Acute cholecystitis
  • Choledocholithiasis (stones in common bile duct)
  • Pancreatitis, cholangitis, biliary obstruction

Two main stone types

Acute Cholecystitis

• Cause — cystic duct obstruction (usually by gallstone) → inflammation
• Presentation
  • Biliary colic + persistent RUQ pain, tenderness
  • Nausea, vomiting, low-grade fever, leukocytosis
  • Murphy's sign: inspiratory arrest with RUQ palpation
• Complications
  • Gangrene, perforation → peritonitis
  • Fistula formation → gallstone ileus (large stone obstructs small bowel)
• Acalculous cholecystitis — occurs without stones; associated with surgery, trauma, sepsis, critical illness

Chronic Cholecystitis

• Pathology — chronic inflammation from recurrent stone-related irritation
• Histology
  • Wall thickening, fibrosis
  • Lymphocytic & plasmacytic infiltrates in stroma and mural layers
  • Macrophages, granulomas may be present
• Clinical — often subtle; may be discovered incidentally or as recurrent RUQ pain

• Definition — bacterial infection of the biliary tree, often due to obstruction (stones, stricture)
• Classic triad (Charcot)
  • RUQ pain
  • Jaundice
  • Fever with chills (often high-grade)
• Organisms — gram-negative enteric bacteria (E. coli, Klebsiella, Enterobacter)
• Pathophysiology
  Obstruction → Stasis → Bacterial overgrowth → Ascending infection
• Diagnosis — clinical + U/S/CT showing dilated ducts; blood cultures; ERCP for therapeutic drainage
• Complications — sepsis, liver abscess, multi-organ failure

Cholesterolosis

• Pathology — accumulation of cholesterol-laden macrophages in the gallbladder mucosa
• Gross — yellow speckling on red-tan mucosa (“strawberry gallbladder”)
• Micro — lipid-laden macrophages in lamina propria
• Clinical — usually asymptomatic; no specific treatment

Hydrops (Mucocele)

• Mechanism — chronic cystic duct obstruction → resorption of bile; distension with clear fluid (hydrops) or mucous (mucocele)
• Palpable — may present as an enlarged, tender gallbladder
• Risk — can lead to perforation or infection if untreated

Gallbladder Carcinoma

• Presentation — often asymptomatic until advanced; may mimic cholecystitis, palpable mass, or obstructive jaundice (late)
• Imaging — “porcelain gallbladder” (calcified wall) on plain X-ray; however, causal link with cancer is debated
• Histology — adenocarcinoma (most common)
• Prognosis — poor; 5-year survival ~12%

Bile Duct Cancers

• Extrahepatic bile duct carcinoma — usually adenocarcinoma; presents with obstructive jaundice
• Cholangiocarcinoma — intrahepatic bile duct carcinoma; risk factors: primary sclerosing cholangitis, Clonorchis sinensis (liver fluke) in Asia
• Klatskin tumor — carcinoma at the bifurcation of right and left hepatic ducts (perihilar)
• Prognosis — generally poor; resection offers only modest survival

Ampulla of Vater Adenocarcinoma

• Location — duodenal, biliary, or pancreatic epithelium at the ampulla
• Presentation — painless jaundice (classic)
• Courvoisier's law — palpable gallbladder in jaundice is more likely due to malignancy (not stones)
• Prognosis — 5-year survival <50% even after resection