Could you explain how the patient transplant list works?
Burton: A patient is carefully evaluated for transplant to look for contraindications or conditions that would make the procedure risky. Each program in the United States does its own evaluation If the patient is a candidate, they get added to the national transplant list. For adult liver transplant patients, their place on the list is based on their blood type, MELD score (Model For End-Stage Liver Disease), and proximity to the donor hospital. The MELD scoring system goes from 6–8 being normal and 40 being the highest. It predicts one's three-month mortality risk without a liver transplant. For example, a patient with a MELD score of 40 has about a 90% risk of death in three months, while a patient with a score of 26 has about a 20% risk. When an organ becomes available, it's offered to the person on the list with the highest MELD score first. Waiting time doesn’t really affect liver transplantation unless two people happen to have the same MELD score simultaneously. For kidney transplantation, on the other hand, it's entirely based on waiting time.
Adams: The pediatric list is similar, but there are some differences. The MELD score is only for candidates 12 and older, whereas kids under 12 have a PELD score (Pediatric End-Stage Liver Disease). From there, the ways organs are allocated depends on your blood type, your proximity to the donor hospital, and your MELD score or PELD score.
What are the different types of donors and donations?
Burton: Most liver donations are performed after brain death, and the organs are procured while the heart is still beating. Donation after circulatory death occurs after the heart has stopped beating and the patient has already passed away. In those cases, the organs have to be procured quickly.
Then there’s living donation. Directed donation is when someone has decided to donate to someone they know, like a family member or friend. When someone's dealing with a family member, it's a little bit like running into a burning building. You'll do anything you can to help that person, but there are definitely risks. That’s why the living donor transplant team evaluates every donor carefully. We have an obligation to ensure that they're making an appropriate decision for themselves and that they understand the risks. And that’s the same for someone who comes forward who has no contact with a patient and is doing it for altruistic reasons. In the past three years, we've had several people come forward who want to be donors but who don't know anyone on the transplant list. These are what we call non-directed donors — altruistic people who really want to help someone. But again, we need to make sure that it's very safe for them.
Adams: We are very fortunate at Children's Hospital Colorado to have the largest altruistic live donor liver transplant program in the country. And Children's benefits from that immensely, in that most of our kids don't have to wait on the list very long. Because if they don't have access to their own living donor, there's often an altruistic or non-directed donor across the street from the UCHealth University of Colorado Hospital (UCH).
Why do you think CU has so many non-directed living donors?
Adams: I think people in Colorado are just uniquely nice and also generally very healthy. One thing that our program does that's a little bit different is we allow altruistic donors who have already donated a kidney to donate a small portion of their liver as well, so they actually become double donors. We usually use those grafts in children so that we’re able to take less liver from the donor, making it a safer operation.
Burton: Even when it comes to driver's license organ donors, Colorado has one of the highest donor rates. Why is that? I don’t know — I think it just has a lot to do with who we are.
We have one of the largest transplant communities for Hispanics. But there's also been a lot of research recently about barriers to transplant for underserved communities. Is that something you've seen in your practice?
Burton: I think that's particularly true in kidney transplantation, and it probably has a lot to do with the Hispanic population having a higher rate of obesity, high blood pressure, and diabetes. This puts those patients at higher risk for developing end-stage renal disease and needing a kidney transplant. For liver transplantation, we’re starting to see more need for liver transplants in patients with non-alcoholic fatty liver disease, and some of the same risk factors that go into end-stage renal disease, like obesity and diabetes, can also be risk factors for non-alcoholic fatty liver disease. So, the need for donors can definitely be greater there. In terms of the donor list, access to organs isn't impacted by race, but these patients may not have as many options for living donor transplants if their family members also have the same medical problems, which is sometimes the case.
Adams: One of my research and clinical interests is increasing organ availability to pediatric patients across the board and better examining socio-economic and racial disparities in terms of who has access to organs. We recently received a grant that will allow us to conduct a series of mini interviews with caregivers or parents of kids who have gotten a transplant to find out what family characteristics either allowed or didn't allow them to be potential donors. Were they ruled out because their anatomy wasn't suitable to be a donor? Or were they ruled out because maybe they’re a family with one breadwinner, and if that breadwinner became a donor and their work wouldn't compensate them to be out for that time, they could no longer provide for the family? Understanding the social background of each different ethnic group will help us care for those patients better and figure out what we can do to help these families so that their kids can get transplanted faster and move on to a normal life.
Another change that’s really helped is making sure we have someone who speaks the language. A couple of years ago we hired a nephrologist who is originally from Puerto Rico and is a very fluent Spanish speaker. She runs a Hispanic kidney clinic, which consists of pre-transplant care and post-transplant care. Now we're hoping to do the same on the liver side.
Is there anything that you're working on specifically or that's happening in the field of transplants in general that you’re particularly excited about?
Burton: One exciting thing that’s happening with non-directed liver donors is that we initially started donating a lot of these organs to kids on the pediatric waitlist, realizing that children are underserved in terms of access to organs. When an adult donates a liver to a child, the surgeon only takes the left lobe of the liver, which is a much safer operation. We actually started running out of kids, because we directed all these organs to the pediatric program. Now it's almost to the point where if a child is going to be listed on the transplant list at Children's Hospital Colorado, we'd likely have someone who's already been evaluated to be a donor. We’ve essentially eliminated the waiting list for children.
We are also working on the opportunity of splitting livers in deceased donors. In the past, if someone wanted to split a liver, the rules said that the split organ that wasn't utilized had to go back to be reallocated again. No program really wanted it after that delay. So there have been some changes that any adult program that's affiliated with a pediatric program can keep the other part of a split liver. For examples, if the left lobe of the liver is going to go to a child over at Children’s Hospital, we have the option to keep the rest of that liver and put the right side of the liver into an adult at UCH. And vice versa. It gives us the ability to help two people with one organ.
Adams: There's a lot of basic science research going on, especially here on campus, about trying to induce what we call tolerance. So, getting the recipient to tolerate a new organ without immunosuppression. That would be amazing to have the recipient accept that organ and merge those cell lines so they can go live a normal life without immunosuppression. That's the holy grail of transplant.
I'm also launching a new social media page for the Division of Transplant to show off what we're doing here and try and encourage families of patients in need of transplants to double list here where we have such short wait times and altruistic donors.
Finally, what’s your main message to someone who might be considering organ donation?
Burton: One of my colleagues used to have a bumper sticker that said, “Don't take your organs to Heaven...Heaven knows we need them here!” There's a huge organ shortage, and every year, many thousands of people die waiting for transplants. A donor can donate a heart, two lungs, two kidneys, and a liver — that means one person can save many lives. And if it’s something you're really interested in, don't just put it on your driver's license. You need to talk to your family as well.
Adams: I think people should understand how easy it is to sign up to be an organ donor. These days you don’t have to go to the DMV, you can just go to the Donate Life website and sign up. It's super simple, and it only takes about five minutes.
If you’re interested in becoming a non-directed, altruistic donor, you can go to the Living Organ Donation page on the UCH website. From there, you can learn more about the process and click on either Liver or Kidney to fill out a short form. After that, you’ll chat with a coordinator either in-person or on the phone to decide if you’d like to proceed with getting lab work and medical and psychological evaluations. The important thing to know if that you're in no way committed. In fact, for each donor there's what's called a donor advocate. This person is there solely to advocate for the donor. If you go through the whole process and you decide donation isn’t for you, there's absolutely no pressure. But if you want to learn more about it, we would be more than happy to sit down talk about it.