Non-Alcoholic Fatty Liver Disease (NAFLD)

Fatty liver disease occurs when too much fat builds up in the liver. Excess fat in the liver and elsewhere in the body makes it harder for the liver to work well.

What Is Non-Alcoholic Fatty Liver Disease in Children?

Fatty liver disease occurs when too much fat builds up in the liver. Excess fat in the liver and elsewhere in the body makes it harder for the liver to work well. Over time, fatty liver disease can cause other serious health issues. It can even cause the liver to become severely damaged, scarred and eventually to fail.

Fatty liver disease used to be seen mainly in adults who drink too much alcohol. However, in non-alcoholic fatty liver disease (NAFLD), not alcohol, but obesity or faulty nutrition are usually the cause.

In recent years, NAFLD has started to develop more and more often in children. Today, NAFLD is the most common chronic (long-lasting) liver disease of childhood in the United States.

There are two main types of NAFLD in children:

  • Non-alcoholic fatty liver (NAFL – “simple” or “bland” NAFLD): At this stage, excess fat has started to build up in the liver. There is no liver inflammation or damage, although these may develop later.
  • Non-alcoholic steatohepatitis (NASH): This is a more severe form of NAFLD. It causes the liver to become inflamed and injured. Scar tissue (fibrosis) starts to form. Over time, the scarring can build up to a point that the normal structure of the liver is destroyed. This is called cirrhosis; it makes it harder for the liver to function and can lead to serious problems in other organs as well.

What Causes Non-Alcoholic Fatty Liver Disease in Children?

Although NAFLD mainly occurs in children who are overweight or obese, its exact cause is not known. Experts do know that NAFLD is seen more often in some ethnic groups than others, so genetic factors do play a role. NAFLD may also be caused by drugs (medications), toxins, infectious, or by certain inherited health problems. 

What Children Are at Risk for Non-Alcoholic Fatty Liver Disease?

For reasons that are not completely understood, children with certain health problems are more likely to develop NAFLD. The main risk factor is obesity or being overweight; other important risk factors are: 

The combination of obesity, high blood sugar, high blood fat and high blood pressure is called “metabolic syndrome.” NAFLD is often seen in patients with the metabolic syndrome. 

Other conditions with a higher risk for NAFLD include:

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Dr. Alexander Weymann leads a team of highly skilled specialists dedicated to caring for children suffering from a wide range of liver diseases. Named to the Best Doctors in America list, Dr. Weymann understands that liver problems can be life-threatening and life-changing. Quick evaluation, correct diagnosis and early treatment can impact long-term health.

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What Are the Symptoms of Non-Alcoholic Fatty Liver Disease in a Child?

Children with NAFLD often do not have any obvious symptoms. As NAFLD gets worse, symptoms may include: 

  • Fatigue (feeling tired all the time) 
  • Pain or discomfort in the upper belly, especially on the right side 
  • Nausea 

Jaundice (yellowish skin and eyes), bleeding, bruising, fever, swollen legs or a painful, swollen abdomen are usually late signs of advanced liver disease and are rarely seen in NAFLD in children. 

How Is Non-Alcoholic Fatty Liver Disease Diagnosed in a Child?

First, your child’s health care provider will ask about past illnesses and surgeries, their current health, acute or chronic complaints, and any medications your child may have taken. He or she will also discuss eating and exercise habits. A physical exam will be done and will include measuring height and weight, as well as looking for outward signs of liver disease such as an enlarged liver or spleen.

If needed, your child’s health care provider will do other tests to look for NAFLD and other liver diseases. These tests may include:

  • Blood tests: These tests allow the provider to measure levels of proteins (such as albumin and certain enzymes), sugar, fats, salts, and other substances such as bilirubin in the blood. Blood tests are also used to count the number of the different types of blood cells and measure the time it takes the blood to clot.
  • Imaging tests: Frequently used types of scans to help diagnose NAFLD include ultrasound and magnetic resonance elastography (MRE). 
  • Endoscopy: A physician uses a special device to look at the inside of the esophagus (food pipe), stomach and intestines (bowel). This is not usually part of the early testing; it is mostly done in advanced, late stages of NAFLD where cirrhosis has already developed. However, it may also be done if other symptoms are present, such as abdominal pain, vomiting, diarrhea or blood loss. 
  • Liver biopsy: Under general anesthesia (with the child completely asleep), a radiologist or surgeon removes a tiny piece of the liver with a needle. The piece is then examined under a microscope. This is the most accurate test to tell for certain if a child has NAFLD. It can also show how much liver damage (inflammation and scarring) is present. However, most children with NAFLD do not need a liver biopsy because usually the history, physical exam and other tests are enough to make the diagnosis. 

How Is Non-Alcoholic Fatty Liver Disease Treated in a Child?

Right now, there are no medicines to treat NAFL (the simple, uncomplicated form of NAFLD) in children. Weight loss is the main treatment. With proper diet and exercise, it is often possible to reverse NAFL. Even for the severe form of NAFLD, called NASH, the main treatment is weight loss through diet and exercise. Because losing weight is hard and involves changing many different things in your life, your child’s provider may refer him or her to a team of specialists, including a dietician, a psychologist, a physical therapist, a social worker, and possibly a specialized physician. 

Medications are rarely used; many drugs have been studied for the treatment of NASH, but so far none have been shown to work well most of the time for most children. If your child is very obese and none of the other treatments have helped, weight loss surgery may sometimes be the best option. Patients who have liver failure due to NASH may need a liver transplant. This is extremely rare in children, even in teenagers. However, for adults in the United States, NASH is now the second most common cause for liver transplantation.

What Are the Complications of Non-Alcoholic Fatty Liver Disease in a Child?

Most children with simple NAFLD do not develop serious complications. Possible complications of advanced NAFLD (NASH) include:

  • Fibrosis and cirrhosis (scar tissue in the liver)
  • Fluid buildup and swelling in the belly (ascites)
  • Jaundice
  • Bruising or bleeding easily
  • Liver failure

When Should I Call My Child’s Health Care Provider?

NAFLD in children needs careful monitoring. Call your child’s health care provider right away if symptoms get worse or new symptoms show up. At the office visit, you should discuss reasons to call your child’s provider and ask about any warning signs to watch out for. 

Key Points About Non-Alcoholic Fatty Liver Disease in Children

  • NAFLD is the most common chronic (long-lasting) liver disease in children in the United States. 
  • The two main types of NAFLD in children are simple nonalcoholic fatty liver (NAFL) and non-alcoholic steatohepatitis (NASH).
  • Most cases of NAFLD are due to obesity or being overweight.
  • Children with NAFLD often have no obvious symptoms.
  • Advanced NAFLD (NASH) can cause serious complications.
  • Weight loss is the main treatment for NAFLD. 
  • Rarely, NASH may need treatment with medicines or surgery. 
  • Patients with liver failure due to NASH may need a liver transplant.

Next Steps

If your child’s NAFLD is due to obesity or being overweight, there are many ways you can help at home. Both healthy eating and regular physical exercise are necessary to treat obesity, but a lifelong balanced diet is the more important part. To improve your child’s eating and exercise habits, a provider may ask you to:

  • Plan healthy family meals: Children may be more likely to eat well when adults set the example. The website is a good place to start for diet advice that the whole family can follow. 
  • Avoid “junk” food, fast food and sugary snacks or drinks: These foods have lots of calories but little nutrition. Many of them have been shown to lead to obesity and to make weight loss very difficult.
  • Encourage exercise: Your child needs to find a physical activity he or she enjoys doing regularly. 45-60 minutes of vigorous exercise three to four times a week should be the goal at first. Swimming, running and team sports are all great ways to get into a routine. Ask your child to join you on a walk, hike or bike ride.
  • Start slowly: It is best to increase physical activity gradually. Your child may get frustrated when asked to do too much in the beginning; any exercise is better than no exercise! Find out if there are any activities your child should not do.
  • Create a good sleep routine: Most children need at least 9-10 hours of sleep each night. Lack of sleep can cause weight gain and obesity. Sleep “hygiene” includes having no TV in the bedroom and switching off all electronic devices 30 minutes before bedtime. 
  • Be careful with home remedies: Ask your child’s health care provider before trying any herbal or other supplements. Some herbal drugs or dietary supplements can be harmful to the liver.