Researchers investigate reasons behind significant improvements in pediatric liver transplantation

A new Johns Hopkins University study of patient and graft survival trends for pediatric liver transplant recipients found that outcomes have improved significantly for alternatives to whole liver transplantation (WLT), such as splitting a liver for two recipients or using part of a liver from a living donor.

The findings were published in TheJournal of Pediatrics, and highlight opportunities for an increased organ supply, better use of those organs, and a chance to save more lives.

“Our study indicates that while there were initially worse outcomes when a whole liver from a deceased donor was given to two recipients—known as a ’split liver transplant’—outcomes are now similar to the classic liver transplant, when a whole liver is given to one recipient,” said Douglas B. Mogul, MD, MPH, assistant professor of pediatrics at the Johns Hopkins University School of Medicine, Baltimore, MD, and the study’s lead author. “Additionally, outcomes when a living donor gives a portion of his or her liver may actually be superior to a whole liver transplant.”

Currently, donor livers from deceased people are allocated to patients based on the Pediatric End-stage Liver Disease (PELD) or Model for End-stage Liver Disease (MELD) system, which provides a score for potential recipients based on how urgently they need a liver transplant within the next 3 months. Persons with high PELD/MELD scores can be subject to long-term physical and mental impairments, hospitalizations, and increased costs until they are sick enough to qualify for a transplant.

Alternatives to WLT can potentially increase organ supply, shorten wait-list times, and reduce pretransplant complications and deaths, according to Dr. Mogul. The alternatives include split liver transplantation (SLT), in which a liver is divided and transplanted into two recipients, and living donor liver transplantation (LDLT), in which a portion of a liver from a live donor is used. The liver of such a donor can regenerate its own tissue.

While there has been an emerging consensus that adult recipients of SLT do just as well as recipients of WLT for several years, outcomes among children have been less clear, Dr. Mogul explained.

To better understand recent outcomes for pediatric liver transplants by transplant type, Dr. Mogul and the research team looked at data for liver-only pediatric transplant recipients from the Scientific Registry of Transplant Recipients, a data system that includes information on all donors, wait-listed candidates, and transplant recipients in the United States.

The research team identified 5,715 pediatric liver-only transplant recipients who received an organ between March 1, 2002, (after implementation of the PELD/MELD system) and December 31, 2015. Of the recipients, 3,428 patients (60%) received a WLT, 1,626 (28.5%) received an SLT, and 661 (11.6%) received an LDLT.

From 2002 to 2009 and 2010 to 2015, 30-day survival for SLT improved (94% to 98%), and 1-year survival increased from 89% to 95%. One-year survival also improved for LDLT, from 93% in 2002 to 2009 to 98% in 2010 to 2015.

The researchers found no change in survival rates for WLT at either 30 days or 1 year. The risk for early death with SLT was 2.14 times higher from 2002 to 2009 compared to WLT, but this risk disappeared in 2010 to 2015. From 2002 to 2009 and 2010 to 2015, the frequency of transplants was similar for WLT (60% for both periods), SLT (29% and 28%) and LDLT (11% and 12%). 

Both SLT and LDLT recipients were more likely to be less than 2 years of age and weigh less than 22 pounds. African-Americans were less likely than Caucasians to receive LDLT and more likely to receive WLT. Donor age for all patients receiving an LDLT was 18-50 years, whereas WLT recipients were more likely to have donors aged 0-17 years. Those undergoing LDLT were more likely to have private insurance, and those with SLT were more likely to have public insurance.

“A recent report tells us that nearly half of all children that died while on the wait list didn’t receive a single offer for an organ,” said Dr. Mogul, who also practices at Johns Hopkins Children’s Center. “Our findings, which show that overall patient and graft survivals have improved, and that outcomes for alternatives to WLT are comparable, will hopefully influence policy for organ allocation, such as greater use of split-liver transplantation.”

One in 10 children on the wait list die each year, and the cost for a pediatric liver transplant is estimated to be between $150,000 and $250,000, he added.

Funding for this study was provided by the Agency for Healthcare Research and Quality and the National Institute of Diabetes and Digestive and Kidney Diseases.

To read more about this study, click here.