Elevated Liver Enzymes
Elevated (too high) levels of liver enzymes are a warning sign that something might be harming the liver.
What Are Elevated Liver Enzymes in Children?
Enzymes are substances that help speed up chemical reactions. Thousands of enzymes are found in the human body. Every day, these enzymes carry out many jobs that are vital to life.
Two of these enzymes are alanine aminotransferase (ALT) and aspartate aminotransferase (AST). These are also called transaminases. It is normal for children to have small amounts of ALT and AST in the blood. ALT is mostly found in the liver. AST is found in many organs, including the liver, pancreas, muscles, heart and brain. This is important because it means that although we call ALT and AST “liver enzymes”, they usually, but not always come from the liver.
There are other liver enzymes that your doctor may test in the blood, such as alkaline phosphatase (AP) or gamma-glutamyltransferase (GGT), but as tests for liver disease in children, ALT and AST are used most commonly.
Elevated (too high) levels of liver enzymes are a warning sign that something might be harming the liver. This may happen for a variety of reasons. Further tests may be needed to find the exact cause.
What Causes Elevated Liver Enzymes in Children?
Most of the time, elevated liver enzymes are due to conditions that are not dangerous, are easily treatable, or go away on their own. Some common causes include:
- Non-alcoholic fatty liver disease (NAFLD). This is probably the main reason for elevated liver enzymes in children in the U.S. today. Mild forms of this disease are very common; the more serious form that over many years can lead to cirrhosis (scarring) and liver failure is called non-alcoholic steatohepatitis (NASH).
- Certain medicines. Drug-induced liver injury (DILI) is another possibility. Medications that can affect the liver include those for attention-deficit/hyperactivity disorder, such as atomoxetine; antibiotics, such as erythromycin or minocycline; anticonvulsants, such as valproic acid; or products containing acetaminophen. Drug-induced liver injury is often mild, but sometimes it can be severe.
- Viral infections. Many viruses can temporarily increase liver enzyme levels. These include rhinovirus (common cold) or Epstein-Barr virus (EBV), the virus that causes mononucleosis (“Mono”).
Rarely are elevated liver enzymes due to a serious or even life-threatening condition. Some of these less common causes include:
- Autoimmune hepatitis (AIH)
- Hepatitis B and C
- Diseases of the bile ducts, such as biliary atresia, choledochal cyst, or bile duct blockage from a gallstone or from pancreatitis
- Diseases of other organs, such as celiac disease, a disorder of the intestine (gut)
- Genetic (inherited) conditions, such as alpha-1 antitrypsin (AAT) deficiency (where a protein gets produced incorrectly and “gets stuck” in the liver), hemochromatosis (too much iron) or Wilson disease (too much copper)
What Are the Symptoms of Elevated Liver Enzymes in a Child?
Many times, childhood liver diseases do not cause obvious symptoms, especially in the early stages. Elevated liver enzymes are often the first sign of liver trouble in children. When symptoms do appear, they may include:
How Are Elevated Liver Enzymes Diagnosed in a Child?
High liver enzymes may show up on a routine blood test during a child’s yearly checkup. A health care provider may also test for elevated liver enzymes when a child is feeling unwell. This is especially true if a child has abdominal pain, vomiting, diarrhea, or jaundice (yellowish color of the eyes or skin).
What Does a Diagnosis of Elevated Liver Enzymes in a Child Mean?
Liver enzyme levels alone are not enough to tell exactly what is wrong with the liver. This is why it is very important to follow up with a child’s health care provider. If high levels of liver enzymes are found, more tests can help determine the cause.
The reason for elevated liver enzymes sometimes appears to be fairly clear. For example, your child’s health care provider may decide that the elevated liver enzymes are probably due to a virus. In these cases, your child’s health care provider may want to wait and see what happens. As the illness clears up, elevated liver enzymes should return to normal levels.
Seeing a Specialist
It is rare for a primary health care provider to not be able to explain why liver enzymes are elevated. However, occasionally your child’s health care provider may suspect something more serious. If so, a doctor who specializes in liver diseases (hepatologist) can help.
Specialized care starts with taking a careful history, and then a physical exam to check for outward signs of liver disease. Such signs may include jaundice or an enlarged liver or spleen.
If liver trouble seems likely, additional tests may include:
- Other liver tests to compare levels of ALT and AST with alkaline phosphatase (AP), gamma-glutamyl transpeptidase (GGT), bilirubin, albumin, prothrombin time etc.
- Specialized lab tests to look for specific diseases, such as celiac disease, autoimmune hepatitis, alpha-1 antitrypsin deficiency, Wilson disease, and viruses such as hepatitis B, hepatitis C, EBV or cytomegalovirus (CMV)
- Imaging tests, such as ultrasound, computerized tomography (CT) or magnetic resonance imaging (MRI), to examine the liver, blood vessels, and nearby organs – especially the spleen.
- Liver biopsy (under anesthesia) to remove a tiny piece of the liver that will be examined under a microscope
Once complete, all of these tests help paint a more complete picture of a child’s liver. This can point the way to the correct diagnosis.
How Are Elevated Liver Enzymes Treated in a Child?
Treatment for elevated liver enzymes depends on the cause. Often, elevated liver enzymes will get better without treatment. For example, if a child has a viral infection, liver enzyme levels may go up for a week or two. When the virus goes away, enzyme levels typically return to normal.
In other cases, simple treatments can help. For instance, NAFLD is a common cause of elevated liver enzymes. Weight loss is the main treatment. As the child loses weight, liver enzyme levels and other symptoms of NAFLD improve.
If elevated liver enzymes are due to something more serious, treatment may include medicines, surgery or other medical procedures.
What Are the Complications of Elevated Liver Enzymes in a Child?
Possible complications of elevated liver enzymes depend on the cause. Most children with elevated liver enzymes do not develop complications. Rarely, children with a serious liver disease may have complications including:
- Cirrhosis (scar tissue in the liver)
- Fluid buildup and swelling in the belly (ascites)
- Severe jaundice
- Liver failure
Should I Call My Child’s Health Care Provider?
Elevated liver enzymes in children must not be ignored. Liver disease in childhood can be very serious or even life-threatening if not properly treated. Call your child’s health care provider right away if your child’s symptoms get worse or new symptoms show up.
Key Points about Elevated Liver Enzymes in Children
- ALT and AST (liver enzymes or transaminases) are normally present in the body and in the blood.
- Elevated liver enzymes in children are often found during a routine blood test.
- Elevated liver enzymes are a warning sign of possible liver damage, irritation or inflammation.
- Elevated liver enzymes are usually due to common conditions that are easily treated or resolve on their own.
- Rarely, they may be due to a serious or even life-threatening disease.
- Liver enzyme levels alone are not enough to tell exactly what is wrong with the liver.
- More tests may be needed to find the reason for elevated liver enzymes.
- Sometimes, no cause for the elevated liver enzymes is found at all; in those cases, the liver enzymes may return to normal on their own.
- Treatment options vary depending on the cause.
Next Steps
If you have been told your child has elevated liver enzymes, your best source of information is your child’s health care provider. He or she will work with you to give your child the best chance of recovery. Some things you can do to help include:
- Learn all you can about recommended treatments. Ask about the benefits and the downsides.
- Keep all follow-up appointments with your child’s health care provider.
- Ask if your child should see a liver disease specialist.
- Ask your child’s health care provider before trying any home remedies or over-the counter medications.
- If there is any concern about liver disease, we do not recommend any supplements or herbal drugs to “help the liver.” No such thing exists, and some products sold for that purpose can be dangerous and may actually harm the liver.
