Liver transplants in children

Liver transplants in children

A little more than one per 10.000 children born, develop a disease that is best treated or is only treatable by a liver transplant. That means that in Denmark, there will be almost 10 children every year, who will need liver transplants.

The liver diseases that are treated with transplants show up in different ways. Most of them cause cirrhosis, which means an increased amount of connective tissue and scarring in the liver. This means that the liver’s functionality will decrease and that it’ll be more difficult for blood to pass through the liver.

The most common reason for this type of liver disease in children is biliary atresia. Children with this disease have no biliary tracts outside the liver. This means that bile can’t run from the liver to the intestine the way it should. These children will turn yellow like many other children right after they are born; but unlike normal jaundice in newborn babies, it won’t disappear in these children. Jaundice that last for more than a few weeks should therefore lead to an examination of the newborns for biliary atresia. A simple blood test will reveal if it might be biliary atresia.

Bilirubin, which is what causes the yellow colour, exists in 2 varieties; conjugated bilirubin and unconjugated. If most of the bilirubin is conjugated, the reason might be biliary atresia and the baby will need to be examined to verify the suspicion. You treat the disease with surgery, where you move a piece of intestine to the liver to replace the missing biliary tracts. It’s important to make the diagnosis as early as possible. If you perform surgery within the first two months of the birth, there’s a fair chance of the surgery succeeding and for the child to develop normally. If the surgery is carried out more than 3 months after the birth, it almost never succeeds. For somewhere between 30% and 50% the operation is partially successful, meaning that bile will reach the intestine and the children will develop normally. However, because of repeated inflammation in the biliary tracts, cirrhosis eventually develops and these children can only be treated with a transplant.

A number of other more rare diseases also cause cirrhosis. Cirrhosis also causes poor liver function and poor development that means the children will stop growing how they’re supposed to. Scar tissue also means blood will have an increasingly harder time passing through the liver. There will be an increased pressure in the blood vessels that carry blood from the other organs to the liver. The most important consequences are the development of oesophageal varices and fluid in the abdomen (ascites). Especially developing oesophageal varices is a serious condition since these may cause considerable bleeding.

Even though you don’t perform a liver transplant without the liver being sick, there are actually a few diseases of the liver that don’t cause damage to the liver itself, but instead to other organs. In these cases, it’s because of an enzyme in the liver that doesn’t work the way it’s supposed to. This might mean that there’s an increased amount of toxins that will hurt other organs rather than the liver itself. For example, the disease primary hyperoxaluria type 1 means a large number of oxalate crystals are formed in the body. The crystals especially damage the kidneys and bones. In hypercholesterolemia, the cholesterol you eat isn’t dealt with properly. This causes arterial plaque and blood clots in the heart at a very young age. It’s important to transplant these children before they become seriously ill from their enzyme defects. That means while they essentially still feel healthy.

Most children receive a liver from an adult. The liver can be divided in various ways so the size can be reduced to 1/8 of its original size and still be usable for transplanting. Even very small children are therefore eligible for transplants using part of an adult liver. The option of using only part of a liver for transplanting also makes it possible to use part of a living adult’s liver for transplants for children. It’s been done several times at Rigshospitalet, with very good results and all parents to children who need transplants, are now informed about the option that one of them could be a donor.

The results of liver transplants on children are good. Approximately 90% of transplants give children the opportunity to live a normal life. It’s important to mention that there aren’t any restrictions for transplant receivers. Children can participate in the same activities as their friends, it’s no more or less dangerous for them to play ball games or go riding because they’ve had a transplant. The children of course need to take their medicine to prevent transplant rejection, but they take this medicine to not get sick rather than because they are sick, it’s an important distinction.

Since we started performing liver transplants in Denmark in 1990, a total of 41 transplants have been done on children, so around 4-5 transplants per year. Much like other places in the world, the most common cause is biliary atresia. In addition to this, a number of transplants have been performed because of cirrhosis for various reasons. Something special for Denmark is that unusually many transplants have been performed because of oxalate crystals in the body. These crystals destroy the kidneys and damage the bones and heart. Almost all patients in the world who have had transplants because of this disease have had kidney failure and have therefore had both liver- and kidney transplants. Something quite unique for Denmark in an international context is that we try to perform liver transplants before the kidneys are destroyed.

The result of liver transplants on children are good and the intention is that the children should be able to live a normal life.

Liver transplants in children” by Allan Rasmussen, RH