 Liver Transplantation
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A liver transplant is an operation performed to replace a diseased liver with a healthy one from another person. An entire liver may be transplanted, or just a section. The liver may come from an organ donor who has died, or from a family member who is willing to donate a part of his/her liver and is a suitable candidate to donate.
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A liver transplant is recommended for children who have serious liver dysfunction and will not be able to live without having the liver replaced. The most common liver disease in children for which transplants are done is biliary atresia. Other diseases may include Alagille's Syndrome, alpha-1-antitrypsin deficiency, Wilson's disease, hepatitis, and hemochromatosis.
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According to the latest statistics from The United Network for Organ Sharing (UNOS), 705 children were waiting for a liver transplant in the United States on June 1, 2007 including:
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- 71 in the under 1 year age group
- 232 in the 1 to 5 years age group
- 165 in the 6 to 10 years age group
- 237 in the 11 to 17 years age group
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Nationally, children account for 4 percent of the 16,857 people who are on the liver transplant waiting list. Approximately 570 children receive liver transplants each year.
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The majority of livers that are transplanted come from organ donors who have died. These organ donors are adults or children who have become critically ill (often due to an accidental injury) and have died as a result of their illness. If the donor is an adult, he/she may have agreed to be an organ donor before becoming ill. Parents or spouses can also agree to donate a relative's organs. Donors can come from any part of the United States. This type of transplant is called a cadaveric transplant.
A child receiving a transplant may get either, or a segment of one. If an adult liver is available and is an appropriate match for two children on the waiting list, the donor liver can be divided into two segments and each part is transplanted.
Living family members may also be able to donate a section of their liver. This type of transplant is called a living-related transplant. Children receiving a partial liver seem to do as well as those receiving a whole liver. Relatives who donate a portion of their liver can live healthy lives with the segment that remains, especially since the residual liver will regenerate to the approximate size of the original liver.
According to the United Network for Organ Sharing, in the first four months of 2006, 576 children (a few months to 17 years of age) received a liver from a cadaveric donor, while 50 children received a liver from a living-related donor.
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The United Network for Organ Sharing is responsible for transplant organ distribution in the United States. UNOS oversees the allocation of many different types of transplants, including liver, kidney, pancreas, heart, lung, and cornea.
UNOS receives data from hospitals and medical centers throughout the country regarding adults and children who need organ transplants. The medical team that currently follows your child is responsible for sending the data to UNOS, and updating them as your child's condition changes. Criteria have been developed to ensure that all people on the waiting list are judged fairly as to the severity of their illness and the urgency of receiving a transplant. Once UNOS receives the data from local hospitals, people waiting for a transplant are placed on a waiting list and given a "status" code and a PELD (if <12 years of age) or MELD (if the child is 12 years of age or >) score. The people in most urgent need of a transplant are placed highest on the status list and are given first priority when a donor liver becomes available.
A PELD (The Pediatric Model for End-stage Liver Disease) score is a continuous disease severity scale that is highly predictive of the risk of dying from liver disease within 3 months for pediatric patients waiting on the transplant list. The PELD score incorporates bilirubin, albumin, INR, sodium and growth failure in an equation. A MELD (The Model for End-stage Liver Disease for older children and adults) score is the same scale as the PELD however it incorporated bilirubin, INR and creatinine only. To find more information about PELD and MELD simply check the UNOS website at www.unos.org or request a brochure about it by calling 1-888-894-6361.
When a donor organ becomes available, a computer searches all the people on the waiting list for a liver and sets aside those who are not good matches for the available liver. A new list is made from the remaining candidates. The person at the top of the specialized list is considered for the transplant. If he/she is not a good candidate, for whatever reason, the next person is considered, and so forth. Some reasons that people lower on the list might be considered before a person at the top include the size of the donor organ and the distance between the donor and the recipient.
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Extensive testing must be done before your child can be placed on the transplant list. Testing includes:
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- blood tests
- diagnostic tests
- psychological and social evaluation of the child (if old enough) and the family
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Blood tests are done to gather information that will help determine how urgent it is that your child is placed on the transplant list, as well as ensure the child receives a donor organ that is a good match. Some of the tests you may already be familiar with, since they evaluate the health of your child's liver and other organs. These tests may include:
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- Liver enzymes - Elevated levels of liver enzymes can alert physicians to liver damage or injury, since the enzymes leak from the liver into the bloodstream under these circumstances.
- Bilirubin - Bilirubin is produced by the liver and is excreted in the bile. Elevated levels of bilirubin often indicate an obstruction of bile flow or a defect in the processing of bile by the liver.
- Albumin, total protein, and globulin - Below-normal levels of proteins made by the liver are associated with many chronic liver disorders.
- Clotting studies, such as prothrombin time (PT) and partial thromboplastin time (PTT) - Tests that measure the time it takes for blood to clot are often used prior to assess liver function. Blood clotting requires vitamin K and proteins made by the liver. Liver cell damage and bile obstruction can both interfere with proper blood clotting.
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Other blood tests will help improve the chances that the donor organ will not be rejected. They may include:
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- Your child's blood type - Each person has a specific blood type: type A+, A -, B+, B -, AB+. AB -, O+, or O -. When receiving a transfusion, the blood received must be a compatible type with your child's type of blood, or an allergic reaction will occur. The same allergic reaction will occur if the blood contained within a donor organ enters your child's body during a transplant. Allergic reactions can be avoided by matching the blood types of your child and the donor, though at times, a liver transplant may be done between donors and recipients of differing blood types.
- Viral studies - These tests determine if your child has viruses that may increase the likelihood of infecting the donor organ, such as cytomegalovirus (CMV).
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Diagnostic tests may include any of the tests that have been done to evaluate the extent of the disease, including:
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- abdominal ultrasound (Also called sonography.) - a diagnostic imaging technique which uses high-frequency sound waves and a computer to create images of blood vessels, tissues, and organs. Ultrasounds are used to view internal organs as they function and assess blood flow through various vessels.
- liver biopsy - a sample of liver tissue is obtained with a special biopsy needle and examined under a microscope.
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Your family will be evaluated by a social worker to determine how well you and your child might cope with a transplant, and to predict how compliant you will be in caring for your child appropriately after the transplant. Although you most likely have been dealing with stressful situations while your child has been ill with liver disease, life can continue to be stressful after your child receives a transplant. Your child will still need to take many medications on a daily basis. Your child will need to be seen by the transplant team on a regular basis. You will also need to teach your child to begin to be responsible for his/her own health when he/she is old enough to understand. All of these things are vital to the success of the transplant.
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There is no definite answer to this question. Sometimes, children wait only a few days or weeks before receiving a donor organ. If no living-related donor is available, it may take months or years on the waiting list before a suitable donor organ is available. Unfortunately, some people die before an acceptable donor organ can be found.
According to UNOS, in 2004, 27 percent of all patients (adults and children) on the waiting list received a cadaveric transplant. Between 1 and 2 percent of all patients received a living donor transplant. Approximately 8 percent of all the people on the waiting list died before a transplant could be found. About 6 percent were taken off the list for various reasons.
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Each transplant team has their own specific guidelines regarding waiting on the transplant list and being notified when a donor organ is available. In most instances, you will notified by phone or pager that an organ is available. You will be told to come to the hospital immediately so your child can be prepared for the transplant.
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Rejection is a normal reaction of the body to a foreign object. When a new liver is placed in a person's body, the body sees the transplanted organ as a threat and tries to attack it. The immune system makes antibodies to try to kill the new organ, not realizing that the transplanted liver is beneficial. To allow the organ to successfully live in a new body, medications must be given to trick the immune system into accepting the transplant and not thinking it is a foreign object.
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Medications must be given for the rest of the child's life to fight rejection. Each child is individual, and each transplant team has preferences for different medications. The anti-rejection medications most commonly used include:
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- Cyclosporine
- Tacrolimus
- Prednisone
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The doses of these medications may change frequently, depending upon your child's response. Because anti-rejection medications affect the immune system, children who receive a transplant will be at higher risk for infections. A balance must be maintained between preventing rejection and making your child very susceptible to infection. Blood tests to measure the amount of medication in the body are done periodically to make sure your child does not get too much or too little of the medications. White blood cells are also an important indicator of how much medication your child needs.
This risk of infection is especially great in the first few months because higher doses of anti-rejection medications are given during this time. Your child will most likely need to take medications to prevent other infections from occurring. Some of the infections your child will be especially susceptible to include oral yeast infection (thrush), herpes, and respiratory viruses.
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The following is a list of symptoms that may indicate rejection:
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- fever greater than 1000 F
- jaundice (yellow skin or eyes)
- dark urine
- itching
- abdominal swelling or tenderness
- fatigue
- irritability
- headache
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Each child may experience symptoms differently. Contact your child's transplant team with any concerns you have.
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Living with a transplant is a life-long process. Medications must be given that trick the immune system so it will not attack the transplanted organ. Other medications must be given to prevent side effects of the anti-rejection medications, such as infection. Frequent visits to and contact with the transplant team are essential. When the child becomes old enough, he/she will need to learn about anti-rejection medications, what they do, the signs of rejection, and everything else the parents have learned so he/she can eventually care for himself/herself independently.
There is no good answer about how long a child can be expected to live after a liver transplant. Every child is different and every transplant is different. Results improve continually as physicians and scientists learn more about how the body deals with transplanted organs and search for ways to improve the success of transplantation. However, many physicians feel that the first year after a transplant is the most difficult, and that the likelihood of living into adulthood is good after getting through the first year. Current national statistics confirm that about 85 percent of children who have had liver transplants survive the first year.
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