Liver Transplantation
Definitive therapy for end-stage liver disease, acute liver failure, unresectable hepatic tumors, and liver-based metabolic defects. Provides survival exceeding 90% in developed nations, transforming previously fatal conditions into manageable chronic states.
Indications for Liver Transplantation
| Category | Specific Conditions |
|---|---|
| Obstructive Biliary Disease | Biliary atresia (most common, 40-50% of pediatric cases), sclerosing cholangitis, Alagille syndrome, progressive familial intrahepatic cholestasis (PFIC). |
| Metabolic (Parenchymal) | Alpha-1-antitrypsin deficiency, Wilson disease, tyrosinemia type I, cystic fibrosis, glycogen storage diseases. |
| Metabolic (Non-Parenchymal) | Crigler-Najjar type I, urea cycle defects, primary hyperoxaluria, familial hypercholesterolemia. |
| Acute Liver Failure (ALF) | Acetaminophen toxicity, viral hepatitis, indeterminate etiology fulfilling King's College criteria. |
| Hepatic Tumors | Unresectable hepatoblastoma, hepatocellular carcinoma, hemangioendothelioma. |
| Chronic Liver Disease | Decompensated cirrhosis featuring ascites, hepatic encephalopathy, spontaneous bacterial peritonitis, hepatorenal syndrome, or hepatopulmonary syndrome. |
Contraindications
| Classification | Conditions |
|---|---|
| Absolute | Extrahepatic malignancy, irreversible severe neurological injury, multisystem organ failure, active uncontrolled sepsis. |
| Absolute | Uncorrectable life-limiting defects in critical organs (kidney, heart, lungs). |
| Relative/Controversial | Mitochondrial hepatopathy, metastatic liver tumors, severe respiratory failure. |
Pre-Transplant Evaluation and Organ Allocation
Allocation systems prioritize medical urgency to reduce waitlist mortality.
- Pediatric End-Stage Liver Disease (PELD) Score: Applied to children <12 years.
- Calculated utilizing age, growth failure extent, serum bilirubin, international normalized ratio (INR), and serum albumin.
- Model for End-Stage Liver Disease (MELD) Score: Applied to children >12 years and adults.
- Calculated utilizing serum bilirubin, serum creatinine, and INR.
Graft Types and Surgical Techniques
Overcomes pediatric donor shortage utilizing anatomical segmental divisions.
- Whole Liver Transplantation: Orthotopic replacement replacing native liver with size-matched deceased donor organ.
- Split/Reduced-Size Grafts: Deceased adult liver divided. Left lateral segment (segments 2, 3) typically utilized for infants.
- Living Donor Liver Transplantation (LDLT): Healthy relative donates hepatic segment (left lateral segment commonly). Offers elective scheduling, excellent quality graft, minimal cold ischemia.
- Auxiliary Liver Transplantation: Native liver retained, partial donor graft implanted orthotopically or heterotopically.
- Functions as temporary bridge in ALF, facilitating native liver regeneration and subsequent immunosuppression withdrawal.
- Provides deficient enzymes in non-cirrhotic metabolic defects (e.g., Crigler-Najjar syndrome).
Post-Transplant Complications and Management
Surgical Complications
- Hepatic Artery Thrombosis (HAT): Most frequent early vascular complication (5-10%). Triggers acute necrosis, gangrene, biliary leaks, and biliary strictures. Constitutes surgical emergency often necessitating retransplantation.
- Portal Vein Thrombosis: Presents with gastrointestinal bleeding, rising INR, worsening ascites. Risk factors include size discrepancy and prior porto-systemic collaterals.
- Biliary Complications: Strictures (anastomotic or ischemic non-anastomotic) and leaks. Most frequent overall surgical complication (10-30%). Managed via endoscopic/percutaneous dilation or surgical revision.
Immunological Complications
- Acute Rejection: Occurs predominantly within first 3 months (30-60% incidence).
- Histology demonstrates interface hepatitis, portal triaditis, central venulitis, and endotheliitis.
- Managed via high-dose corticosteroids and augmented baseline immunosuppression.
- Chronic Rejection: Progressive ductopenia (loss of bile ductules) and cholestasis.
Immunosuppression Side Effects
| Medication | Key Adverse Effects |
|---|---|
| Corticosteroids | Hypertension, diabetes, osteoporosis, growth delay, cataracts. |
| Calcineurin Inhibitors (Cyclosporine) | Nephrotoxicity, hypertension, hypercholesterolemia. |
| Calcineurin Inhibitors (Tacrolimus) | Nephrotoxicity, diabetes, neurotoxicity. |
| Sirolimus | Bone marrow suppression, hyperlipidemia. |
| Mycophenolate Mofetil | Bone marrow suppression, colitis, gastrointestinal discomfort. |
Medical and Infectious Complications
- Infections: Bacterial sepsis (common first week), Cytomegalovirus (CMV), Epstein-Barr virus (EBV), opportunistic fungal pathogens (Pneumocystis jiroveci).
- Long-Term Morbidity: Post-transplant lymphoproliferative disease (PTLD) linked to EBV, renal dysfunction secondary to calcineurin inhibitors, de novo autoimmune hepatitis, and transplant-acquired food allergy (TAFA).
Outcomes
- 1-year patient survival rates approximate 83-95% depending on etiology.
- 5-year patient survival rates approximate 75-78%.
- Long-term catch-up growth typically observed within 2 years post-transplant, though final height may remain below genetic potential.