Cholangitis

Definition: Acute bacterial infection of the bile ducts resulting from common bile duct obstruction. Also called ascending cholangitis. Mortality rate 5-10%

Hepatobiliary Tract Anatomy

Pathophysiology

• Bile duct develops an obstruction
  • Obstruction may be incomplete (more common) or complete
  • Causes: Gallstones (most common), malignancy, benign stricture, iatrogenic (i.e. ERCP), biliary parasites, primary sclerosing cholangitis (PSC)
• Elevated intraluminal pressure in the gallbladder leads to translocation of bacteria
  • Bacteria may gain access via lymphatics, portal venous blood or retrograde from the duodenum
  • Common pathogens: E. coli, Klebsiella,  Streptococcus, Enterobacter, Pseudomonas   Other causes: HIV/AIDS cholangiopathy, parasitic infections (Ascaris lumbricoides)

Presentation

• Charcot’s Triad: Fever, RUQ pain and jaundice (neither sensitive nor specific)
• Symptoms
  • Fever/chills
  • Nausea/vomiting
  • Abdominal pain
• Physical Exam
  • RUQ tenderness to palpation
  • Peritoneal signs are variable
  • Jaundice
  • Frank sepsis (fever, tachycardia, hypotension, tachypnea) is a common presentation
  • Reynold’s Pentad: Charcot’s triad + sepsis and AMS

Acute Cholangitis Infographic (mediconet.blogspot.com)

Diagnostics

• Cholangitis is a clinical diagnosis. There are no diagnostic tests that absolutely clinches or rules out the diagnosis.
• Laboratory Tests
  • Lab tests are generally neither sensitive nor specific for ruling in or ruling out cholangitis. Below are common findings
  • WBCs – usually elevated but may be depressed in severe infection
  • Hepatic panel
    • Elevated aminotransferases (i.e ALT/AST)
    • Elevated alkaline phosphatase
    • Hyperbilirubinemia
  • Lipase – useful to evaluate for concomitant pancreatitis
  • Blood gas may be useful in patients who appear septic to record lactate level
  • Blood cultures
• Imaging
  • Imaging is helpful in supporting the diagnosis and aids in identifying the cause. Many patients will have concomitant acute cholecystitis that will be identified on imaging
  • Ultrasound (US)
    

    Ultrasound with Dilated Common Bile Duct (CBD)

    • Common findings
      • Intrahepatic biliary ductal dilation (see video below)
      • Thickening of the bile duct walls
      • Obstructing gallstones
    • Concomitant cholecystitis findings
      • 4 sonographic signs of cholecystitis: Gallstones, gallbladder wall thickening >3mm, pericholecystic fluid, sonographic murphy’s
      • Gallstones + sonographic murphy’s
      • Highly sensitive (87-95%) and specific (82%) when examining the gallbladder and biliary ducts (Carmody 2011, Summers 2010)
    • Not highly sensitive for diagnosing choledocholithiasis: can miss distal CBD stones
    • Useful to distinguish between intrahepatic and extrahepatic obstruction
  • CT Scan
  • Classic finding: non-homogenous liver enhancement during arterial phase
  • Can identify dilated intra- and extrahepatic ducts
  • Gallstones are poorly visualized
  • Findings non-specific
  • Can identify other pathologies or complications of cholangitis (perforation, abscess)
  • Other Diagnostic Imaging
    • Nuclear scintigraphy: may be more sensitive than US in identifying early obstruction
      • Useful when ultrasound results are equivocal and the diagnosis is suspected
      • Cannot visualize the biliary tree with complete obstruction
    • Endoscopic Retrograde Cholangiopancreatography (ERCP)
      • Procedure is both diagnostic + potentially therapeutic
      • Allows removal of obstructing stone, biopsy of mass, culture of bile and decompression or stent placement
    • Magnetic resonance cholangiopancreatography (MRCP)
      • Most sensitive noninvasive method
      • Requires patient to be stable to obtain study

Immediate Management:

Basics:

• ABCs, IV, Cardiac Monitor
• Unstable patients due to sepsis or septic shock should be aggressively resuscitated per general sepsis/septic shock algorithms (IV fluids, airway management as necessary, vasoactive substances etc.)

Directed Management

• Broad spectrum antibiotics
  • Antibiotics should cover gram positive, anaerobic  gram negative aerobic andenteric organisms (see above)
  • Common regimens
    • Piperacillin/tazobactam (Zosyn®)
    • Imipenem/Meropenem
    • Ampicillin/sulbactam (Unasyn®) + metronidazole
• Correct electrolyte abnormalities and coagulopathies if present
• Biliary tract decompression
  • Percutaneous drainage via interventional radiology
  • ERCP via gastroenterology
    • Should be performed emergently if the patient fails to improve with aggressive resuscitation
    • In resuscitation responders, should be performed within 24 hours
  • Surgical drainage

Disposition:

• All patients with cholangitis will require admission and many will require a high-resource setting (ICU or step down unit)

Take Home Points

1. Cholangitis is a potentially life-threatening (mortality 5-10%), acute bacterial infection of the bile ducts
2. Diagnosis is based on clinical findings and while imaging can be supportive, it is frequently non-diagnostic
3. A normal ultrasound does not rule out acute cholangitis
4. Treatment focuses on supportive care, broad spectrum antibiotics and consultation with a provider that can provide biliary tract decompression (IR, gastroenterology or general surgery)

Read More

Radiopaedia: Acute cholangitis

References

Oyama LC: Disorders of the liver and biliary tract, in Marx JA, Hockberger RS, Walls RM, et al (eds): Rosen’s Emergency Medicine: Concepts and Clinical Practice, ed 8. St. Louis, Mosby, Inc., 2010, (Ch) 90: p 1186-1205.

Summers S et al. A Prospective Evaluation of Emergency Department Bedside Ultrasonography for the Detection of Acute Cholecystitis. Ann Emerg Med. 2010;56(2): 114-122. PMID: 20138397

Carmody KA, Moore CL, Feller-Kopman D, (eds). Handbook of Critical Care & Emergency Ultrasound. New York, NY: McGraw Hill, 2011, pp.123-144.

Richter J et al. Ultrasound in Tropical and Parasitic Diseases. Lancet 2003; 362:900-902. PMID: 13678978