Liver Transplantation¶
Chapter 356 | Part 10: Disorders of the Gastrointestinal System
KEY CLINICAL POINTS¶
- Liver transplantation is the replacement of a diseased liver with a healthy donor organ, now a standard treatment for end-stage liver disease.
- Indications include biliary atresia in children, metabolic disorders, and cirrhosis from various causes (e.g., alcohol, hepatitis B/C, NAFLD).
- Contraindications include active infections, severe comorbidities, and advanced age (>70 years) as a relative contraindication.
- Immunosuppressive drugs like tacrolimus and mycophenolate are critical to prevent rejection, with cyclosporine being less commonly used due to nephrotoxicity.
- Post-transplant complications include rejection, infection, vascular issues, and long-term risks like diabetes and cardiovascular disease.
1. DEFINITION & OVERVIEW¶
Liver transplantation involves replacing a diseased liver with a healthy donor organ. It has evolved from an experimental procedure to a standard treatment for end-stage liver disease. Orthotopic transplantation, where the donor liver is placed in the recipient's anatomical position, is the preferred method. Success rates have improved significantly due to advances in surgical techniques, immunosuppression, and donor organ preservation.
Table 356-1 Indications for Liver Transplantation¶
| CHILDREN | ADULTS |
|---|---|
| Biliary atresia | Primary biliary cholangitis |
| Neonatal hepatitis | Primary sclerosing cholangitis |
| Congenital hepatic fibrosis | Caroli’s disease |
| Alagille’s syndrome | Secondary biliary cirrhosis |
| Byler’s disease | Autoimmune hepatitis |
| Inherited disorders of metabolism | Hemochromatosis-associated cirrhosis |
| Wilson’s disease | a Antitrypsin deficiency |
| Tyrosinemia | Metabolic dysfunction–associated steatohepatitis (MASH) |
| Glycogen storage diseases | Alcohol-associated cirrhosis |
| Lysosomal storage diseases | Severe alcohol-associated hepatitis |
| Protoporphyria | Cryptogenic cirrhosis |
| CHILDREN | ADULTS |
|---|---|
| Crigler-Najjar disease type I | Chronic viral hepatitis with cirrhosis |
| Familial hypercholesterolemia | Hepatic venous outflow obstruction |
| Primary hyperoxaluria type I | Acute liver failure (ALF) |
| Hemophilia | Hepatocellular carcinoma |
| Hepatocellular carcinoma | Select cases for the following indications: Hepatic adenomas, Familial amyloidosis, Hepatic epithelioid hemangioendothelioma (HEHE), Erythropoietic protoporphyria (EPP), Metastatic neuroendocrine tumors, Polycystic liver disease |
Table 356-2 Contraindications to Liver Transplantation¶
| ABSOLUTE | RELATIVE |
|---|---|
| Uncontrolled extrahepatobiliary infection | Advanced agea |
| Active, untreated sepsis | Prior extensive hepatobiliary surgery |
| Life-limiting congenital anomalies | Extensive portal vein thrombosis |
| Cholangiocarcinoma (except those tumors that fit into protocols) | Renal failure not attributable to liver disease |
| Advanced cardiopulmonary disease | Extrahepatobiliary malignancy |
| Severe obesity | Severe malnutrition/wasting |
| Medical noncompliance | Severe hypoxemia secondary to right-to-left intrapulmonary shunts (PO <50 mmHg) |
| AIDS HIV seropositivity with failure to control HIV viremia or CD4 <100/mL | Severe pulmonary hypertension (mean pulmonary artery pressure >35 mmHg) |
| Active substance use disorder | Uncontrolled psychiatric disorder |
Table 356-3 United Network for Organ Sharing (UNOS) Liver Transplantation Waiting List Criteria¶
| STATUS | CRITERIA |
|---|---|
| Status 1 | Acute liver failure (including primary graft nonfunction and hepatic artery thrombosis) |
| Status 2 | Chronic liver failure with complications (e.g., hepatic encephalopathy, ascites, variceal bleeding) |
| Status 3 | Chronic liver failure without complications |
| Status 4 | Chronic liver failure with minimal complications |
1.1 Indications¶
Indications include end-stage liver disease from various causes (e.g., cirrhosis, metabolic disorders, biliary atresia). Specific conditions like primary biliary cholangitis, autoimmune hepatitis, and hepatocellular carcinoma are also considered. Children may require transplantation for biliary atresia or metabolic disorders.
1.2 Contraindications¶
Absolute contraindications include active infections, uncontrolled systemic diseases, and metastatic malignancy. Relative contraindications include advanced age (>70 years), severe comorbidities, and certain vascular abnormalities.
2. EPIDEMIOLOGY¶
Liver transplantation is a critical intervention for end-stage liver disease. In the U.S., over 9,500 transplants were performed in 2022, with demand exceeding supply. The MELD score is used to prioritize recipients, with higher scores indicating greater urgency. The most common indications include steatotic liver disease (MASLD/NAFLD), alcohol-associated cirrhosis, and viral hepatitis (HCV, HBV).
2.1 Demographics¶
The majority of recipients are adults, with a growing number of pediatric cases. The median age for adult recipients is around 50–60 years. The waiting list includes patients with various etiologies, including metabolic disorders, autoimmune diseases, and malignancies.
2.2 Risk Factors¶
Risk factors include chronic alcohol use, viral hepatitis (HCV, HBV), metabolic syndrome, and genetic disorders. Patients with advanced cirrhosis or complications like hepatic encephalopathy are at higher risk for poor outcomes.
3. ETIOLOGY & PATHOPHYSIOLOGY¶
Liver failure leading to transplantation arises from various etiologies, including viral hepatitis, alcohol abuse, metabolic disorders, and autoimmune conditions. The pathophysiology involves progressive liver damage, fibrosis, and eventual cirrhosis. Infections, immune-mediated injury, and metabolic derangements contribute to disease progression.
3.1 Viral Hepatitis¶
Chronic hepatitis B and C are major causes of end-stage liver disease. HCV leads to progressive fibrosis and cirrhosis, while HBV can cause fulminant hepatitis or chronic infection. Antiviral therapy (e.g., DAA) has improved outcomes post-transplant.
3.2 Metabolic and Genetic Disorders¶
Inherited disorders like Wilson’s disease, α 1-antitrypsin deficiency, and Crigler-Najjar syndrome require transplantation to prevent irreversible liver damage. These conditions often present with unique clinical features and require specialized management.
4. CLINICAL FEATURES¶
Clinical manifestations vary by underlying disease. Common features include jaundice, ascites, hepatic encephalopathy, and coagulopathy. Acute liver failure (ALF) presents with rapid deterioration, while chronic conditions like cirrhosis may present with complications such as variceal bleeding or spontaneous bacterial peritonitis.
4.1 Acute vs. Chronic Presentation¶
Acute liver failure (ALF) is characterized by rapid onset of jaundice, coagulopathy, and encephalopathy. Chronic liver disease presents with progressive symptoms like fatigue, ascites, and portal hypertension.
4.2 Complications¶
Complications include hepatic encephalopathy, ascites, spontaneous bacterial peritonitis, and variceal bleeding. Post-transplant complications include rejection, infection, and vascular issues.
5. DIFFERENTIAL DIAGNOSIS¶
Differential diagnoses include other liver diseases (e.g., viral hepatitis, autoimmune hepatitis), metabolic disorders, and malignancies. Conditions like Wilson’s disease or hemochromatosis may mimic cirrhosis but require specific testing for confirmation.
5.1 Non-Transplant-Related Conditions¶
Conditions like alcoholic liver disease, non-alcoholic steatohepatitis (NASH), and viral hepatitis must be differentiated from transplant indications. Autoimmune diseases (e.g., primary sclerosing cholangitis) may also mimic transplant-related pathology.
5.2 Malignancies¶
Hepatocellular carcinoma (HCC) and cholangiocarcinoma must be ruled out in patients with liver disease. Imaging and biopsy are critical for differentiation.
6. INVESTIGATIONS & DIAGNOSIS¶
Diagnosis involves clinical evaluation, imaging (ultrasound, CT, MRI), and laboratory tests. The MELD score is used to prioritize recipients. Liver biopsy may be required for certain conditions, while non-invasive tests like FibroScan or APRI score assess fibrosis.
6.1 Laboratory Tests¶
Key tests include liver function tests (ALT, AST, bilirubin, INR), viral hepatitis panels, and coagulation studies. HBIg and HBV DNA levels are monitored in post-transplant patients.
6.2 Imaging¶
Imaging modalities like ultrasound, CT, and MRI help assess liver morphology, portal hypertension, and complications like varices or tumors.
7. MANAGEMENT & TREATMENT¶
Management includes immunosuppression, antiviral therapy, and post-transplant care. Immunosuppressive drugs like tacrolimus, mycophenolate, and corticosteroids are used to prevent rejection. Antiviral therapy (e.g., DAA) is critical for HCV and HBV to prevent recurrence.
7.1 Immunosuppressive Therapy¶
Standard regimens include tacrolimus, mycophenolate mofetil, and corticosteroids. Cyclosporine is less commonly used due to nephrotoxicity. Sirolimus and everolimus are alternatives for certain patients.
7.2 Antiviral Therapy¶
DAA therapy is used for HCV to prevent recurrence. Prophylactic HBIg and antiviral drugs (e.g., entecavir, tenofovir) are used for HBV. Post-transplant monitoring is essential to prevent viral reactivation.
8. PROGNOSIS & COMPLICATIONS¶
Post-transplant survival rates have improved significantly, with 5-year survival exceeding 60%. Complications include rejection, infection, vascular issues, and long-term risks like diabetes and cardiovascular disease. Recurrence of primary disease (e.g., HCV, HBV) is a major concern.
8.1 Survival Rates¶
One-year survival rates are ~85–90%, with 5-year survival exceeding 60%. High MELD scores (>25) correlate with poorer outcomes. Age >65 and comorbidities increase mortality risk.
8.2 Long-Term Complications¶
Long-term complications include diabetes, hypertension, osteoporosis, and cardiovascular disease. Chronic rejection and recurrent viral hepatitis are leading causes of late mortality.
9. SPECIAL CONSIDERATIONS¶
Special considerations include pediatric transplantation, HIV/HCV co-infection, and management of metabolic disorders. Pregnancy is possible post-transplant, but requires careful monitoring. Patients with HIV can undergo transplantation with effective antiretroviral therapy.
9.1 Pediatric Considerations¶
Pediatric transplantation is indicated for biliary atresia, metabolic disorders, and certain malignancies. Living-donor transplants (e.g., left lobe) are common. Growth and development must be closely monitored.
9.2 HIV and HCV Management¶
HIV-positive patients with controlled viremia can undergo transplantation. DAA therapy for HCV post-transplant reduces recurrence. Antiretroviral therapy is essential to prevent viral reactivation.
10. KEY POINTS & CLINICAL PEARLS¶
Key points include the use of MELD/PELD scores for prioritization, the role of immunosuppressive drugs, and the importance of antiviral therapy. Clinical pearls include monitoring for rejection, managing complications, and ensuring adherence to immunosuppression. Early detection of recurrence and prompt intervention are critical for long-term success.