Living Donor Liver Transplantation: Impact on Access to Care
Summary of CME Lecture by Daniel Maluf, MD
1. Main Clinical Topics Discussed
- Current state of liver transplantation in the United States, with emphasis on the organ supply-demand gap
- The role of living donor liver transplantation (LDLT) in expanding access to care
- Challenges threatening the deceased donor organ supply (aging, obesity, NASH, alcohol-related liver disease)
- Institutional and regulatory factors influencing LDLT program development
- Comparative analysis of LDLT utilization in Western versus Eastern countries
2. Key Learning Points, Guidelines, and Recommendations
Organ Supply Challenges:
- Aging donor population, rising obesity, NASH, and alcohol-related liver disease are progressively degrading deceased donor organ quality
- Approximately 20% of potential donors have fatty liver disease; steatosis >60% typically precludes organ utilization
- Increasing use of alcohol post-COVID has compounded donor organ quality concerns
- Predictive modeling suggests a potential 48% decline in viable donor organs if trends in obesity and aging continue unchecked
Living Donor Liver Transplantation:
- LDLT remains underutilized in Western countries despite excellent outcomes comparable to Eastern programs
- Both right and left lobe donations have demonstrated strong outcomes; lobe selection is typically center-specific
- LDLT is particularly valuable for patients with MELD scores below 25–27 who are unlikely to receive a deceased donor organ in a timely manner
- LDLT programs are resource-intensive and require institutional commitment, experienced surgeons, hepatologists, and dedicated ICU support
Expanding the Donor Pool (Marginal/Extended Criteria Donors):
- Centers are increasingly accepting hepatitis B core-positive, hepatitis C-positive, older-age, fatty liver, and DCD (donation after cardiac death) organs
- Normothermic machine perfusion is an emerging but costly tool to improve utilization of marginal grafts
Regulatory Considerations:
- Recent UNOS/SRTR regulatory changes now evaluate transplant programs on four parameters: outcomes at 3 months, outcomes at 1 year, and waitlist mortality — potentially incentivizing LDLT program development
3. Specific Clinical Data and Statistics Cited
- 2021 U.S. waitlist: Approximately 11,000 patients listed for liver transplantation (down from >15,000 in 2013)
- Total liver transplants performed (2021): 9,236 — representing ~3.7% growth from 2020; projected ~4% growth annually
- Waitlist mortality:
- University of Maryland: ~10.5%
- National average: 12.5–14%
- Transplant within 1 year of listing:
- University of Maryland: ~51%
- National average: ~50%
- Living donor transplants:
- Declined sharply after the first donor death in 2001
- Reached a nadir around 2009
- 2021 volume: ~569 living donor liver transplants (~6% of all liver transplants)
- 2022 projected: ~600 LDLT cases — approaching but not yet surpassing the 2001 peak
- LDLT as proportion of total transplants in the U.S.: Grew from 3.3% (2008) to 5% (2018)
- LDLT decline noted in both the UK and Canada during the same 2008–2018 period
- NASH prevalence in the U.S.: 10–30% of liver biopsies; ~20% of donors have fatty liver disease
- Median MELD at transplant at University of Maryland: approximately 27–30
4. Practical Takeaways for Clinicians
- Identify LDLT candidates early: Patients with MELD <25–27, symptomatic complications (ascites, encephalopathy), or conditions limiting access to deceased donor organs (e.g., hepatocellular carcinoma within or beyond Milan criteria) should be evaluated for LDLT proactively
- LDLT program development is institution-specific: The decision to build or expand a LDLT program must account for local waitlist volume, waitlist mortality, transplant oncology caseload