Non-Alcoholic Fatty Liver Disease (NAFLD)
What is a non-alcoholic fatty liver disease (NAFLD)?
Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease in the United States. Sometimes referred to as "fatty liver disease," it is actually a range of diseases that all begin when excess fat gets deposited in the liver.
As the disease becomes more severe, inflammation or irritation of the liver occurs and then scar tissue (fibrosis) develops. The disease is then referred to as NASH (non-alcoholic steatohepatitis).
If the scar tissue is extensive, cirrhosis develops and the liver may function poorly.
The exact cause(s) of NAFLD is currently unknown. It is likely a combination of several factors, including a genetic background that puts children at higher risk of the disease combined with environmental triggers that can cause insulin resistance and pre-diabetes and the accumulation of specific fats in the liver.
Once the process begins, activation of the immune system and oxidative likely cause ongoing damage.
Who gets non-alcoholic fatty liver disease?
NAFLD affects approximately 30 million people, 8.6 million of whom have the more severe form of the disease, NASH. NAFLD affects almost 10% of all children in the United States.
Approximately 1% of 2 to 4 year olds and 17% of 15 to 19 year olds have NAFLD. In addition, 38% of obese children have NAFLD. Among adults, NAFLD has become a leading cause for liver transplant. Children, who will live the longest time with the disease, are at particular risk of complications and poor prognosis, including the need for liver transplant in adulthood.
Most children with NAFLD are in their early adolescent years. NAFLD, however, is being increasingly observed in young children. Males are affected twice as often as females and Hispanics are more likely to develop NAFLD than non-Hispanics, whites or Blacks. Obese children are at the greatest risk for developing NAFLD. In addition, having type 2 diabetes or pre-diabetes, the metabolic syndrome, or high blood lipids increases the risk of developing NAFLD.
What are the signs and symptoms of non-alcoholic fatty liver disease?
Most commonly, children with NAFLD don't show any symptoms. In these cases, a doctor may notice abnormal blood tests during a routine well-child check up. Some children experience right sided abdominal pain, fatigue or constipation.
During the exam, doctors may find obesity, especially a large waist area, an enlarged liver, signs of insulin resistance called acanthosis nigricans, a dark discoloration on the back of the neck and armpits, or the exam may be completely normal.
What tests are used to diagnose non-alcoholic fatty liver disease?
The diagnosis of NAFLD is made through a combination of a physical exam with a doctor, blood test results, special X-rays of a child's abdomen and, often, a liver biopsy done by a doctor when a child is under anesthesia. During this procedure a small amount of tissue is taken from the liver so it can be examined under a microscope to look for fatty deposits and scarring.
How do doctors at Children's Hospital Colorado make a diagnosis?
In order to diagnose NAFLD, your doctor will start with blood tests to look for abnormally high levels of liver enzymes. They may also run blood tests for pre-diabetes and high blood lipids and try to exclude other causes of liver disease, such as viral hepatitis, autoimmune hepatitis and Wilson's disease. They may check an abdominal ultrasound to look for fat deposits in the liver. The only way to be certain that your child has NAFLD, however, is a liver biopsy. This test allows your child's doctor to determine if your child has NAFLD and the severity of the disease.
How is non-alcoholic fatty liver disease treated?
Currently, there is no specific medication to treat NAFLD. However, there are many research trials studying NAFLD that ultimately may lead to effective medications in the future.
Right now, NAFLD is treated with gradual weight loss of about one pound per week. Research shows that for many children, losing just 10% of their body weight can help their liver disease. This should occur through a combination of both exercise and changes to the child's diet. A reasonable goal is to exercise 3 to 5 times per week for at least 30 minutes.
Exercise not only helps to burn stored calories, but also increases the body's metabolism. Nutrition should be balanced and include a regular breakfast. Sugar sweetened beverages should be limited and lean meats, poultry and fish, along with fresh fruits and vegetables and whole grains emphasized.
Why choose Children's Colorado for your child's NAFLD?
Children's Colorado provides comprehensive, child-specific state of the art care for children with non alcoholic fatty liver disease. Children with this condition are cared for by a team of specialists, including hepatologists (liver doctors), nurses and nutritionists who are NAFLD experts. In addition, Children's Colorado hosts an innovative research program focused on non alcoholic fatty liver disease that aims to further understand this condition to improve the lives of current and future children who are affected. Learn more about our Pediatric Liver Center.
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