What is the recommended endoscopic treatment for Primary Sclerosing Cholangitis (PSC)?

Endoscopic Treatment of Primary Sclerosing Cholangitis

Balloon dilation alone is the preferred first-line endoscopic treatment for dominant strictures in PSC, with stenting reserved only for strictures that fail to respond to balloon dilation. 1, 2

When to Perform ERCP

ERCP should not be performed until after expert multidisciplinary assessment and confirmation of a therapeutic indication. 1 Magnetic resonance cholangiography (MRCP) must be performed first as the primary diagnostic modality, not ERCP. 1, 3

Specific Indications for Therapeutic ERCP:

• Symptomatic deterioration: New or worsening jaundice, cholangitis (fever/chills), or progressive pruritus 1
• Biochemical progression: Rapid increase in serum bilirubin or cholestatic enzymes (alkaline phosphatase, GGT) 1
• Imaging findings: New dominant stricture or progression of existing dominant strictures on MRCP with appropriate clinical context 1

Important caveat: Do not use CA19-9 elevation alone to trigger ERCP—it has poor sensitivity (14%) and positive predictive value (67%) for cholangiocarcinoma. 1

Pre-Procedure Requirements

Mandatory Steps Before ERCP:

• Prophylactic antibiotics must be administered routinely before every ERCP in PSC patients 1, 2, 3
• MRCP imaging should be performed before therapeutic ERCP to identify target strictures 1
• Multidisciplinary review to confirm appropriateness of intervention 1

Endoscopic Treatment Algorithm

First-Line: Balloon Dilation Alone

Balloon dilation without stenting is the preferred initial approach for all dominant strictures. 1, 2 This recommendation is based on a randomized controlled trial (DILSTENT) that was prematurely stopped due to significantly higher serious adverse events with stenting (45%) compared to balloon dilation alone (7%). 1, 2

Technical Specifications:

• Balloon size: 6-8 mm for hepatic ducts; up to 8 mm for common bile duct 2
• Success criteria: Complete balloon inflation with no waist visible fluoroscopically, followed by unobstructed contrast passage 2
• Repeat sessions: Typically requires 2-3 sessions at 1-4 week intervals, with 80-90% technical success rate 2, 4

Advantages of Balloon Dilation:

• Lower complication rates (15% vs 54% with stenting) 2
• Bile duct perforation rate only 0.2% 1, 2
• Lower cholangitis risk compared to stenting 1, 5

Second-Line: Short-Term Stenting

Stenting should only be used when strictures fail to respond adequately to balloon dilation alone. 1, 2 If stenting is necessary, use short-term stenting rather than long-term stenting to minimize complications. 1, 2

Long-term stenting is associated with higher rates of stent clogging and cholangitis and should be avoided. 2

Biliary Sphincterotomy Decision

Do not perform routine biliary sphincterotomy—assess benefits versus risks on a case-by-case basis. 1, 3

When to Consider Sphincterotomy:

• After difficult cannulation 1, 3
• In patients likely to require multiple repeat ERCPs 2

Rationale: While sphincterotomy increases short-term adverse events in PSC, it may be protective for subsequent procedures. 2

Mandatory Tissue Sampling

Ductal sampling with brush cytology and endobiliary biopsies is mandatory during ERCP for any suspicious stricture. 1, 3 This is critical because cholangiocarcinoma develops in 10-20% of PSC patients. 6

Red Flags for Cholangiocarcinoma:

• Worsening cholestasis with weight loss 1, 3
• New or progressive dominant stricture 1, 3
• Raised CA19-9 (though not specific) 1, 3
• Associated enhancing mass lesion on imaging 1, 3

Procedural Technique to Minimize Complications

Aspirate bile before contrast injection during ERCP. 5 A prospective study demonstrated that bile aspiration prior to contrast injection, combined with balloon dilation without stenting, was associated with zero adverse events (0% vs 18.6% with traditional approach). 5

On multivariate analysis, biliary stent placement was the only factor independently associated with increased risk of adverse events (OR 4.10) and cholangitis (OR 5.43). 5

Follow-Up Strategy

Multiple dilations are typically required over months to years to maintain stricture patency. 1 In a large prospective study of 96 patients undergoing regular balloon dilations over 7 years, complication rates were low: 2.2% pancreatitis, 1.4% cholangitis, 0.2% perforation. 1

Common Pitfalls to Avoid

• Do not perform ERCP as initial diagnostic test—always obtain MRCP first 1, 3
• Do not place stents routinely—balloon dilation alone is safer and equally effective 1, 2
• Do not skip tissue sampling—cholangiocarcinoma risk is substantial and unpredictable 1, 7, 3
• Do not forget prophylactic antibiotics—cholangitis risk is significant in PSC 1, 2, 3
• Do not inject contrast before aspirating bile—this increases adverse event risk 5