Cholangitis / Cholecystitis

Last updated: April 8, 2026, 3:12 PM Pacific Time (PDT)
Shared disease framework for acute biliary infection and inflammation. Use it to separate cholangitis from cholecystitis, identify obstruction or sepsis, and match antibiotics with source control.
All Clinical risk factors Diagnostics Confirmation criteria Management Back to Main Page

Disease Pathway

risk factors -> diagnostics -> differential / confirmation -> syndrome-based management
Clinical Risk Factors

Who should trigger biliary infection reasoning?

  • RUQ or epigastric pain, fever, jaundice, nausea/vomiting, or sepsis without clear source
  • Known gallstones, prior biliary colic, choledocholithiasis, biliary stent, ERCP history, or recent biliary instrumentation
  • Cholestatic labs, hyperbilirubinemia, or dilated ducts on prior imaging
  • Older age, immunocompromise, malignancy, or obstruction from stone/tumor make cholangitis more dangerous
  • Shock, confusion, hypotension, or rising lactate should push toward urgent source control thinking
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Diagnostics

Order studies that define infection, obstruction, and need for intervention

Core labs
  • CBC
  • CMP
  • Direct bilirubin
  • Alkaline phosphatase
  • Lactate
  • Blood cultures
Additional labs
  • Lipase
  • PT / INR
  • Creatinine trend
Imaging / diagnostics
  • RUQ ultrasound
  • CT abdomen / pelvis
  • MRCP
  • HIDA scan
Procedures
  • ERCP
  • Percutaneous cholecystostomy
  • Cholecystectomy
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Differential Diagnosis

Keep alternate hepatobiliary and abdominal diagnoses in play

Key mimics
  • Biliary colic without infection
  • Gallstone pancreatitis
  • Hepatitis / cholestatic liver injury
  • Hepatic abscess
  • Peptic ulcer disease / perforation
  • Pyelonephritis or other intra-abdominal sepsis
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Confirm Diagnosis

Separate duct infection from gallbladder inflammation

  • Acute cholangitis: systemic inflammation plus cholestasis plus imaging or clinical evidence of biliary obstruction.
  • Acute cholecystitis: RUQ pain/tenderness plus inflammatory markers plus supportive imaging, often gallbladder wall thickening, stones, or sonographic Murphy sign.
  • Choledocholithiasis without cholangitis: obstructive pattern or duct stone without systemic infection syndrome.
  • Severe disease: hypotension, altered mental status, rising lactate, organ dysfunction, or inability to control source promptly.
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Management

Select the working biliary syndrome

Current picture

Resident Pearls

Bedside Use

  • Think cholangitis when fever or sepsis is paired with cholestatic labs or ductal obstruction.
  • RUQ ultrasound is the usual first imaging test, but it does not rule out ductal stone or cholangitis by itself.
  • Antibiotics help, but cholangitis often turns on whether you can decompress the duct.
  • For cholecystitis, source control is usually surgery or percutaneous drainage rather than ERCP unless a ductal process is also present.
  • If the patient is unstable, call GI, surgery, and ICU early rather than waiting for perfect imaging.

Sources