What is Nonalcoholic Fatty Liver Disease?
When someone is overweight or obese, too much fat can be stored in the liver. This can lead to a disease called nonalcoholic fatty liver disease, or NAFLD.
In some children and adults, the extra fat in the liver becomes a more severe problem, causing swelling and scar tissue. When this happens, it is called nonalcoholic steatohepatitis, (stee-at-oh-hep-a-titus), or NASH. Over time, NASH can lead to severe scarring, called cirrhosis (sir-oh-sis). Cirrhosis can lead to liver failure and loss of liver function.
Causes of Fatty Liver Disease
The exact causes of fatty liver disease are not known, but risk factors include:
- Being overweight or obese, especially around the waist
- Diabetes and insulin resistance
- High levels of triglycerides in the blood (fat in the blood)
- Race and ethnicity (Caucasians, Hispanic and Native Americans are at greater risk)
Signs and Symptoms of Fatty Liver Disease
- Pain in the right upper part of the belly
- Feeling tired
- Increased levels of liver enzymes in the blood
Because children who have fatty liver disease (NAFLD and/or NASH) may not have any symptoms, your child's doctor will check his/her liver enzyme levels by taking a sample of blood. Normal liver enzyme levels vary with a child's age.
Causes of High Liver Enzymes
- Fatty liver or NASH
- Viral infections
- Certain medicines
- Physical activity
- Muscle injury
- Gall stones
Your child's liver doctor may recommend further testing if your child's liver enzymes are very high.
Diagnosis of NASH
The only way to determine if your child has NASH is to perform a liver biopsy. There is a special MRI that provides some sense of how severe the NASH is and, if necessary, a liver biopsy can be done. A liver biopsy is a special test that places a needle through the skin to get a small piece of tissue from the liver. Your child's doctor will look at this tissue to see if there is any scarring.
One out of four children with NASH may eventually develop severe liver disease and scarring. Early diagnosis is very important. Once we know for sure with a biopsy that the liver disease is from NAFLD / NASH then we can use a special MRI scan to understand how stiff the liver is and how it is changing over time.
Treatment for NAFLD and NASH
Right now, the only way to treat NAFLD and NASH is to have the child lose weight through healthy eating and increased physical activity. Usually the liver disease is reversible if it is in the early stages and no scarring is found. Some medicines, such as vitamin E, have been shown in studies to improve severe fatty liver disease or NASH in some adults and children. It is not yet clear why these medicines don’t work for everyone, but genes and other risk factors may play a role. These medicines should be used only for children under the care of a liver doctor, where the response to the medicine can be closely followed.
- Encourage your child to follow a healthy portion-controlled diet, with low amounts of saturated fats and refined sugars.
- Avoid large portion sizes and sweetened drinks, like soda. Limit the amount of meals eaten at fast food restaurants, since this food is usually high in fat.
- We encourage you to visit with the dietitian to learn about healthy diet choices for your child and family.
- Increasing physical activity and outdoor play is a great way to help children achieve and keep a healthy weight.
A child with NAFLD or NASH should have hepatitis B and A vaccinations to avoid potential injury to the liver caused by these viral infections.
Call Your Child's Doctor If:
- Becomes jaundiced (skin and/or eyes turn yellow or green in color)
- Complains of increased belly pain or swelling of the belly or legs
- Becomes more short of breath with exercise