Biliary Disease
Gallstones and their complications — from asymptomatic stones through cholecystitis, ductal obstruction, cholangitis, and biliary malignancy.
High-Yield Points
- Cholesterol stones (most common in the US) form from stasis + decreased bile salts/lecithin; pigment stones are most common worldwide — black stones from hemolysis/cirrhosis/TPN (in the gallbladder), brown stones from biliary stasis/infection (primary CBD stones, often E. coli β-glucuronidase).
- Biliary colic = transient cystic-duct obstruction, pain <4–6 h, normal labs/US inflammation → elective laparoscopic cholecystectomy.
- Acute cholecystitis = cystic-duct obstruction + inflammation: fever, positive Murphy sign, wall ≥4 mm/pericholecystic fluid on US. RUQ ultrasound is the best initial test; HIDA (non-visualization of the gallbladder) when US is equivocal. Treat with IV fluids + antibiotics + early (same-admission) lap chole.
- Acalculous cholecystitis — critically ill/TPN/burns/trauma, no stones → percutaneous cholecystostomy if unstable. Emphysematous (gas in wall, diabetic men) → Clostridium perfringens → emergent cholecystectomy.
- Choledocholithiasis: jaundice + dilated CBD (>6–8 mm) + ↑alk phos/bilirubin. High probability/visualized stone → ERCP; intermediate probability → MRCP/EUS/IOC first.
- Ascending cholangitis = obstructed, infected biliary tree. Antibiotics + IV fluids FIRST, then ERCP decompression (PTC if ERCP fails). E. coli is the #1 organism.
- Gallstone ileus — large stone erodes a cholecystoduodenal fistula, lodges at the terminal ileum; Rigler triad (SBO + pneumobilia + ectopic stone) → enterolithotomy, leave the fistula.
- Biliary dyskinesia — biliary pain, no stones, CCK-HIDA ejection fraction <35–40% → laparoscopic cholecystectomy.
- Gallbladder adenocarcinoma (most common biliary-tract cancer) — risk = gallstones, large (>3 cm) stones, porcelain GB; Tis/T1 → simple cholecystectomy; T2–T4 → radical cholecystectomy (segments IVb/V + portal nodes). Porcelain gallbladder → cholecystectomy.
- Cholangiocarcinoma — painless jaundice, weight loss, ↑bili/alk phos; risk = PSC/UC, choledochal cysts, liver flukes. MRCP to map, ERCP brushings for tissue, CA 19-9. Klatskin (hilar) = most common, worst prognosis.
- Post-cholecystectomy bile leak = usually cystic-duct stump → US → drain biloma → ERCP sphincterotomy ± stent. Complete CBD transection (Strasberg E) → Roux-en-Y hepaticojejunostomy (primary repair strictures due to 3- and 9-o'clock blood supply).
Key Tables / Differentials
| Syndrome | Pain | Fever/WBC | LFTs | US/Key | First step |
|---|---|---|---|---|---|
| Biliary colic | <4–6 h, resolves | No | Normal | Stones, no wall change | Elective lap chole |
| Acute cholecystitis | Constant >6 h, Murphy+ | Yes | Mild ↑ | Wall ≥4 mm, fluid | US → abx + early lap chole |
| Choledocholithiasis | RUQ, jaundice | No | ↑↑ alk phos/bili | Dilated CBD ± stone | ERCP (or MRCP if intermediate) |
| Cholangitis | Charcot triad | Yes | ↑↑ | Dilated CBD | Abx + fluids → ERCP |
Board Pearls
- Charcot triad (RUQ pain + fever + jaundice) → cholangitis; + shock + AMS = Reynolds pentad → emergent ERCP decompression.
- Air in the biliary tree (pneumobilia) → most commonly prior ERCP/sphincterotomy; with SBO → gallstone ileus.
- Highest PPV for biliary obstruction = alkaline phosphatase.
- Calot's (hepatocystic) triangle = cystic duct / common hepatic duct / liver edge; cystic artery = branch of the right hepatic artery; confirm the critical view of safety (only 2 structures) before clipping.
- Mirizzi syndrome — stone in the GB neck/cystic duct compressing the common hepatic duct.
Classic Vignette Triggers
- "Gas in the gallbladder wall in a diabetic" → emphysematous cholecystitis (Clostridium).
- "ICU patient on TPN, RUQ pain, no stones" → acalculous cholecystitis → cholecystostomy.
- "Elderly woman, SBO, pneumobilia, ectopic stone" → gallstone ileus → enterolithotomy.
- "Painless jaundice + ulcerative colitis + hilar stricture" → cholangiocarcinoma (Klatskin).
- "POD#3 after lap chole, bilious drain/biloma" → cystic-duct stump leak → ERCP + stent.