Definition of Cholangitis
Cholangitis is an infectious disease characterized by acute inflammation and infection of the bile ducts resulting from a combination of biliary obstruction and bacterial growth in bile. 1
Core Pathophysiology
Cholangitis develops when bacteria colonize an obstructed biliary system. Bacteria reach the biliary tract either by:
- Ascending from the intestine
- Through the portal venous system 2
Once the biliary system is colonized, biliary stasis allows bacterial multiplication, and increased biliary pressures enable bacteria to penetrate cellular barriers and enter the bloodstream 2. The most common cause is choledocholithiasis (common bile duct stones), though neoplasia and strictures are also important etiologies 1, 3.
Diagnostic Criteria
The diagnosis of acute cholangitis requires three components 4, 5:
- Clinical signs: Jaundice, fever, chills, and right upper quadrant abdominal pain
- Laboratory findings: Indicators of inflammation (elevated WBC, CRP) and biliary stasis (elevated alkaline phosphatase, bilirubin)
- Imaging findings: Biliary dilatation or evidence of an etiology (stricture, stone, obstructing mass)
Classic Presentations
- Charcot's triad (fever, jaundice, right upper quadrant pain) - though this has insufficient sensitivity 3
- Reynolds pentad (Charcot's triad plus hypotension and altered mental status) - indicates severe disease 6
Special Context: Cholangitis in Primary Sclerosing Cholangitis (PSC)
The definition and diagnosis of acute cholangitis in PSC is particularly challenging, as symptoms may be atypical and standard definitions (Tokyo guidelines) may not be universally applicable 7.
Recently proposed PSC-specific criteria require either:
- Single criterion: Suppurative cholangitis on ERCP, OR
- At least 1 major criterion (temperature >38°C, leukocyte count >12/nl, or CRP >75 mg/L) PLUS at least 2 minor criteria (positive bile culture, increase in ALP or total bilirubin above 2x ULN, no other focus of infection) 7
Important Caveats in PSC
- Signs can be mild and nonspecific
- Patients may present without significant change in baseline liver biochemistry
- Infections can be limited to smaller bile ducts
- In milder cases, only the response to antibiotics confirms the clinically suspected diagnosis 7
Clinical Significance
Cholangitis represents a life-threatening emergency that historically carried nearly 100% mortality if untreated 6. Even with modern management including early antibiotics and biliary decompression, mortality remains approximately 5% 3. The infection is typically polymicrobial, predominantly involving gram-negative rods, particularly Escherichia coli and Klebsiella species 3.