Biliary Tract Disease

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What this chapter covers

• Section 27.1: Cholelithiasis stone biology and risk factors

  Three stone phenotypes derive from three distinct biochemical environments.

• Section 27.2: Symptomatic cholelithiasis and indications for cholecystectomy

  Roughly 10 percent of US adults harbor stones and 75 percent are asymptomatic.

• Section 27.3: Acute cholecystitis Tokyo grading and treatment

  Persistent cystic duct obstruction by an impacted stone converts simple colic into acute cholecystitis: bile becomes increasingly concentrated, mucosal phospholipase liberates lysolecithin, and bacterial superinfection follows, with right-upper-quadrant pain, fever, leukocytosis, and a positive Murphy sign.

• Section 27.4: Acalculous cholecystitis and emphysematous variants

  Acalculous cholecystitis accounts for approximately 5 to 10 percent of acute cholecystitis but carries higher mortality (commonly cited at 30 to 50 percent in critically ill patients) for two mechanistic reasons: it occurs in fasting, often intubated trauma, surgical, burn, or septic patients where the diagnosis is delayed by sedation, paralysis, and competing diagnoses, and the pathogenesis (gallbladder ischemia from low-flow states with prolonged TPN, sepsis, or vasopressor exposure, plus cystic duct functional obstruction from inspissated bile) leads more rapidly to gangrenous wall progression than calculous disease.

• Section 27.5: Mirizzi syndrome and porcelain gallbladder

  Mirizzi syndrome (less than 1 percent of cholelithiasis complications) is extrinsic compression of the common hepatic duct by a stone impacted in the cystic duct or Hartmann's pouch at Calot's triangle, with chronic local inflammation that may progress to a cholecystocholedochal fistula.

• Section 27.6: Gallstone ileus and Bouveret syndrome

  A long-standing impacted gallstone with chronic inflammation can erode through the gallbladder wall into an adjacent hollow viscus, creating a cholecystenteric fistula (most often cholecystoduodenal, sometimes cholecystocolonic, gastric, or jejunal).

• Section 27.7: Gallbladder polyps and adenocarcinoma

  Gallbladder polyps are seen on approximately 5 percent of ultrasounds; 95 percent are benign.

• Section 27.8: Functional gallbladder disorder

  Rome IV criteria define functional gallbladder pain as biliary-type pain (epigastric or RUQ, at least 30 minutes long, severe enough to interrupt activities, not relieved by bowel movement, antacids, or postural change) in the absence of stones, sludge, microlithiasis, or other structural disease, with normal liver chemistries and normal lipase or amylase.

• Section 27.9: Choledocholithiasis and ASGE 2019 risk stratification

  Bile duct stones present with biliary colic plus more pronounced liver enzyme elevation, jaundice when obstruction is complete or prolonged, cholangitis when bacterial infection supervenes, and gallstone pancreatitis when the stone impacts at the ampulla.

• Section 27.10: Acute cholangitis and Tokyo Guidelines

  Cholangitis is ascending bacterial infection of an obstructed biliary tree, most commonly from choledocholithiasis but also from malignancy, anastomotic stricture, or stent occlusion.

• Section 27.11: Choledochal cysts and Caroli disease

  Todani classifies cystic dilations of the bile duct into five types that reflect anatomic location and dictate surgical strategy.

• Section 27.12: Bile leak and post-cholecystectomy stricture

  Bile leaks typically present within 10 days of cholecystectomy with abdominal pain or bile peritonitis, fever, leukocytosis, and elevated liver enzymes; persistent bilious drain output or biliary ascites confirms the diagnosis on imaging.

• Section 27.13: Sphincter of Oddi dysfunction (Rome IV)

  Sphincter of Oddi dysfunction is a non-calculous obstructive disorder at the level of the sphincter of Oddi caused by either passive obstruction from fibrosis or inflammation or active sphincter spasm; the two mechanisms are not mutually exclusive.

Podcast episodes

1. 01

   Biliary Tract Disease: Stones and Cholecystitis

   Gallstones cause one clear symptom, biliary colic, and almost every decision in this episode follows from whether stones are causing trouble or are likely to. A woman with colic shows how to separate her dyspepsia from what stones cause, why her gallbladder should come out, and how her stones trace to cholesterol, black pigment, or brown pigment mechanisms. Asymptomatic stones are then observed unless cancer risk or the surgical setting justifies removal. Acute cholecystitis follows: diagnosis by the Tokyo criteria, ultrasound first and HIDA second, liver tests that point to a duct stone, grading, and timing of surgery. The episode ends with drainage for a patient too sick to operate.

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2. 02

   Biliary Tract Disease: Gallbladder Complications

   Gallbladder disease goes well beyond simple cholecystitis, and each complication has a recognizable setting and its own treatment rule. The episode begins with the two dangerous acute variants, acalculous cholecystitis in the fasting, sedated ICU patient and emphysematous cholecystitis in the diabetic patient, both needing rapid decompression and broad antibiotics. It then turns to what a stone left for years can do: Mirizzi syndrome, porcelain gallbladder, gallstone ileus, and Bouveret syndrome. Next it covers the four types of gallbladder polyp and the size and risk factor thresholds that separate surgery from rescanning. It ends with gallbladder cancer, which presents late and is usually unresectable.

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3. 03

   Biliary Tract Disease: Stones and Cholangitis

   Duct stones and the infection they cause are managed by probability and by the clock. The episode begins with the ASGE 2019 system, which sorts suspected choledocholithiasis into high, intermediate, and low probability and so decides who goes straight to ERCP, who needs EUS or MRCP first, and who goes to cholecystectomy. It then covers stones of one centimeter or more and the frail patient whose gallbladder stays in. It turns to acute cholangitis, an obstructed, infected duct that antibiotics cannot sterilize, graded by Tokyo 2018 to set drainage within 24 or 48 hours, followed by antibiotic choice and rescue drainage when ERCP cannot reach the papilla.

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4. 04

   Biliary Tract Disease: Functional Pain and Ducts

   This episode separates biliary problems that look structural from those that are functional, and then covers the bile duct defects a patient is born with or given at surgery. It starts with Rome four functional gallbladder pain, the weak meaning of a low ejection fraction, and why sphincter of Oddi dysfunction now justifies ERCP only when enzymes or duct size are abnormal, with full pancreatitis prophylaxis. It then turns to choledochal cysts, where the Todani type sets the operation, and to Caroli disease. It ends with bile leaks and strictures after cholecystectomy, classified by Strasberg type, treated with a stent, hepaticojejunostomy, or serial dilation.

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Key topics

• ·Biliary colic recognition
• ·Dyspepsia and gallstones
• ·Indications for cholecystectomy
• ·Cholesterol and pigment stone formation
• ·Asymptomatic gallstones
• ·Prophylactic cholecystectomy indications
• ·Diagnosis of acute cholecystitis
• ·Tokyo grading and timing of surgery
• ·Gallbladder drainage in poor surgical candidates
• ·Acalculous cholecystitis in the ICU
• ·Morphine-augmented HIDA scan
• ·Percutaneous cholecystostomy
• ·Emphysematous cholecystitis
• ·Mirizzi syndrome and Csendes classification
• ·Porcelain gallbladder
• ·Gallstone ileus and Bouveret syndrome
• ·Gallbladder polyp types and size thresholds
• ·Polyps in primary sclerosing cholangitis
• ·Gallbladder cancer risk factors
• ·Presentation of duct stones
• ·ASGE 2019 probability levels
• ·EUS versus MRCP for small stones
• ·When ERCP is the wrong move
• ·Stones of one centimeter or more
• ·Gallbladder after duct clearance in frail patients
• ·Acute cholangitis and the Charcot triad and Reynolds pentad
• ·Tokyo 2018 severity grades and drainage timing
• ·Empiric antibiotic choice
• ·Rescue drainage after altered anatomy
• ·Rome four functional gallbladder pain