What is cholangitis?

What is Cholangitis

Cholangitis is a bacterial infection of the bile ducts that results from the combination of biliary obstruction and bacterial colonization, representing a potentially life-threatening condition that requires prompt recognition and treatment. 1, 2

Pathophysiology

Cholangitis develops through a specific pathogenic mechanism requiring two essential components:

• Biliary obstruction is the most critical predisposing factor—without obstruction, cholangitis does not develop 3, 2
• Bacterial colonization of the biliary system occurs either by ascent from the intestine or through the portal venous system 1, 2
• Once bacteria colonize an obstructed biliary system, biliary stasis allows bacterial multiplication, and increased biliary pressures enable bacteria to penetrate cellular barriers and enter the bloodstream 2

Common Causes

The etiology of cholangitis has evolved over time:

• Choledocholithiasis (bile duct stones) remains the most common cause overall 1, 4
• Biliary strictures (benign or malignant) are increasingly common, particularly at tertiary referral centers 1
• Previous biliary instrumentation (ERCP with or without stenting) significantly increases risk, with positive bile culture rates reaching 98% when stents are left in situ 1
• Primary sclerosing cholangitis (PSC) represents a specific high-risk population where cholangitis is a common complication, occurring in 13% of patients over 2 years 1

Clinical Presentation

The classic presentation has become less uniform in modern practice:

• Charcot's triad (fever/chills, jaundice, and right upper quadrant pain) was historically considered classic but is now seen less frequently, particularly in patients with indwelling biliary tubes 3, 4
• Fever and elevated inflammatory markers are the most consistent findings 3
• Laboratory abnormalities typically include leukocytosis, elevated bilirubin, and elevated alkaline phosphatase 3, 4
• Atypical presentations are common—patients may present without significant jaundice if they have indwelling tubes, and infections can be limited to small liver segments without significant changes in baseline liver biochemistry 1

Microbiology

The bacterial spectrum is predictable but varies by clinical context:

• Polymicrobial infections are common 1
• Most frequent organisms include Escherichia coli, Klebsiella, Enterococcus, Clostridium, Streptococcus, Pseudomonas, and Bacteroides species 1
• Patients with indwelling tubes or previous antibiotic exposure increasingly harbor Enterobacter, Pseudomonas, and even Candida species (isolated in 12% of PSC patients undergoing ERCP) 1, 4
• Antibiotic resistance is an emerging concern, particularly in patients with recurrent episodes 5

Severity and Prognosis

Cholangitis exists on a spectrum from mild to life-threatening:

• Severe/toxic cholangitis (presenting with hypotension and altered mental status) occurs in 5-10% of patients and requires emergency biliary decompression 4
• Mortality rates range from 5% in uncomplicated cases to 15% overall, with higher rates in patients with malignant obstruction or delayed treatment 1, 5
• The nature of biliary obstruction is the most important determinant of outcome—patients with end-stage malignant obstruction account for most deaths, while approximately 95% of patients with benign causes survive 4

Critical Management Principles

Understanding cholangitis requires recognizing that successful treatment depends on two pillars:

• Antibiotic therapy to manage septic complications 1, 6
• Biliary decompression to restore biliary drainage and relieve obstruction 1, 3

Delayed intervention is associated with elevated morbidity and mortality rates, increased ICU admission likelihood, and prolonged hospitalization 1, 3