Biliary Diversion for PFIC
Partial external biliary diversion (PEBD) or ileal exclusion (IE) should be performed early in children with FIC1 (PFIC1) and BSEP deficiency (PFIC2) who have refractory pruritus and cholestasis, but only before the development of cirrhosis, as the procedure is ineffective once severe fibrosis is established. 1
Indications for Biliary Diversion
Timing is Critical
The effectiveness of biliary diversion depends entirely on performing the procedure before cirrhosis develops. Once severe fibrosis or cirrhosis is established, biliary diversion fails to improve biochemical parameters or symptoms 2, 3.
Specific Indications by PFIC Type
FIC1 Disease (PFIC1):
- Severe, refractory pruritus despite ursodeoxycholic acid (UDCA) trial
- Progressive cholestasis with elevated bile acids
- Mild to moderate fibrosis on biopsy (not severe fibrosis/cirrhosis)
- PEBD or IE can significantly slow disease progression with improvements in cholestasis, pruritus, and growth 1
BSEP Deficiency (PFIC2):
- Similar indications as PFIC1
- However, PFIC2 responds less favorably to biliary diversion compared to PFIC1 4
- Higher risk of hepatocellular carcinoma makes liver transplantation often more appropriate 3
- Individual bile acid response post-diversion predicts transplant need 4
MDR3 Deficiency (PFIC3):
- Biliary diversion is NOT typically indicated 1
- UDCA improves biochemical tests in approximately 50% of PFIC3 patients 3
- Liver transplantation is indicated for those who fail UDCA therapy 1
Preferred Surgical Options
Partial Internal Biliary Diversion (PIBD)
This is the preferred approach based on recent evidence:
- Lower complication rate than PEBD (21.8% vs 38%, p=0.02) 5
- Lower liver transplantation requirement (10.7% vs 32%) 5
- Higher pruritus resolution rate (72% vs 57%) 5
- No external stoma, avoiding associated morbidity 6
- Technique: cholecystojejunocolic anastomosis using jejunal conduit
Partial External Biliary Diversion (PEBD)
- Historically more common but has higher complications 5
- Creates permanent external stoma with associated quality of life issues
- Effective in 57% for pruritus relief 5
- Long-term complications include stoma-related problems and fat-soluble vitamin deficiencies 7
Ileal Exclusion (IE)
- Alternative to PEBD/PIBD
- Similar efficacy to PEBD (48% pruritus resolution) 5
- Avoids external stoma
Critical Predictors of Success
Post-operative bile acid levels are the strongest predictor of outcome:
- Absolute decrease in bile acids (AUROC 0.72) discriminates responders from non-responders 5
- Post-operative bile acid level (AUROC 0.9) determines need for liver transplantation 5
- In PFIC1, bile acids, cholesterol, and triglycerides significantly decrease post-diversion; in PFIC2, they often do not 4
Important Caveats
FIC1 Disease-Specific Warning
Liver transplantation in FIC1 should only be considered if PEBD or IE failed or could not be performed 1. This is because ATP8B1 is expressed in extrahepatic organs (intestine, pancreas), and post-transplant complications include:
- Worsening diarrhea
- Short stature
- Pancreatic dysfunction
- These extrahepatic manifestations may worsen quality of life despite resolving liver disease 1
When Biliary Diversion Fails
Proceed to liver transplantation when:
- Cirrhosis already established at diagnosis
- No biochemical response (bile acids remain elevated) post-diversion
- Progressive liver dysfunction despite diversion
- Development of hepatocellular carcinoma (particularly PFIC2) 3
Monitoring Requirements Post-Diversion
- Intensive fat-soluble vitamin supplementation required, especially vitamin K 8
- Regular monitoring of vitamins A, D, E, K levels
- Growth parameters
- Bile acid levels to assess response
- Liver function tests and bilirubin
Emerging Alternative
Recent evidence suggests ileal bile acid transport inhibitors (IBATi) may serve as medical alternatives to surgical biliary diversion, potentially even allowing reversal of prior surgical interventions 9, 10. However, these are newer therapies requiring further long-term data.