Someone who needs a liver transplant is referred to a transplant center to be evaluated by a team of specialists from a variety of fields. Once the person completes all required testing, the transplant committee reviews the information. If the committee determines the person is a suitable candidate to receive a transplant, his or her name is placed on the national transplant waiting list. This list is managed by the United Network for Organ Sharing (UNOS), which administers the Organ Procurement and Transplantation Network (OPTN), responsible for transplant organ distribution in the U.S. The organ allocation system ensures that organs from deceased donors go to the sickest people first.
When people are put on the waiting list they’re assigned a priority score indicating how urgently they need a transplant. The score is calculated by their healthcare provider based on a specific formula. The two scoring systems are the MELD (Model for End-stage Liver Disease) used for adults, and the PELD (Pediatric End-stage Liver Disease), used for children less than 12 years of age.
MELD scores range from 6 to 40 and are based on whether the person is on dialysis or not and the results of the following four blood tests:
- INR (internal normalized ration), an indicator of the liver making the proteins necessary for a person’s blood to clot
- Creatinine, an indicator of kidney function
- Bilirubin, an indicator of liver health
- Sodium, an indicator of the body’s ability to regulate fluid balance
PELD scores range from negative numbers to 99 and are based on the:
- Child’s age
- Child’s degree of growth failure
- Results of the following blood tests: INR, bilirubin, and albumin – a protein made by the liver which is usually below normal levels in people with liver disease
A higher MELD or PELD score indicates a more urgent need for a liver transplant. For example, people with (liver?) cancer receive additional MELD points. While someone is on the waiting list, their score may go up if their condition worsens or down if it improves.
A small group of people who are critically ill with acute liver failure and likely to die within a week have the highest priority on the waiting list. More information about these scoring systems is available from UNOS.