INTRODUCTION — Nonalcoholic fatty liver disease (NAFLD) is a medical condition that is characterized by the buildup of fat (called fatty infiltration) in the liver. There are two types of fatty infiltration of the liver:
Nonalcoholic fatty liver (NAFL) is a generally benign condition in which the fatty infiltration is simple and there is no inflammation
Nonalcoholic steatohepatitis (NASH) in which there is fatty infiltration along with liver inflammation (steatohepatitis)
To be diagnosed with either form, a person cannot have a history of heavy alcohol use or another problem that might be causing the liver condition (such as an infection with the hepatitis C virus).
NONALCOHOLIC FATTY LIVER — Nonalcoholic fatty liver (NAFL) is a generally benign condition that has become increasingly common in the United States and Western Europe as weight gain and obesity have become more common. It is now the most common cause of liver disorder in the United States. Liver blood tests are either normal, or there may be slight increases in two of the enzymes made by the liver, the serum ALT and/or the serum AST. The diagnosis may be confirmed with an ultrasound examination.
NONALCOHOLIC STEATOHEPATITIS — Nonalcoholic steatohepatitis (NASH) is a condition that causes inflammation and accumulation of fat and fibrous (scar) tissue in the liver. Liver enzyme levels in the blood may be more elevated than the mild elevations seen with nonalcoholic fatty liver (NAFL). The exact cause of NASH is unknown. However, it is seen more frequently in people with certain medical conditions such as diabetes, obesity, and insulin resistance. This combination of disorders if often called the metabolic syndrome.
It is not clear how many people have NASH because it causes no symptoms. Most people are between the ages of 40 and 60 years. NASH is seen more often in women than in men.
The cause of NASH is not clear, although research is ongoing to find effective treatments.
Conditions associated with nonalcoholic steatohepatitis — NASH is most frequently seen in people with one of more of the following conditions.
Obesity – More than 70 percent of people with NASH are obese.
Diabetes – Up to 75 percent of people with NASH have type 2 diabetes.
Hyperlipidemia – About 20 to 80 percent of people with NASH have hyperlipidemia (high blood triglyceride levels and/or high blood cholesterol levels).
Insulin resistance – Insulin resistance refers to a state in which the body does not respond adequately to insulin. Insulin resistance often occurs in people with hyperlipidemia who are obese; this group of symptoms is known as the metabolic syndrome and is frequently seen in people with NASH.
Drugs and toxins – Several drugs have been linked to NASH, including amiodarone, tamoxifen, steroids (e.g., prednisone, hydrocortisone), and synthetic estrogens.
Nonalcoholic steatohepatitis symptoms — Most people with NASH have no symptoms.
NASH is most often discovered during routine laboratory testing. Imaging tests (such as ultrasound, CT scan, or magnetic resonance imaging [MRI]) may reveal fat accumulation in the liver but cannot differentiate NASH from other causes of liver disease that have a similar appearance.
Liver biopsy and fibroscan — Although other tests may suggest a diagnosis of NASH, sometimes a liver biopsy is required to confirm it.
A Fibroscan is a noninvasive test that uses ultrasound to determine how "stiff" the liver is. This stiffness can then be used to estimate how much scarring there is in the liver and to determine if cirrhosis has developed.
Nonalcoholic steatohepatitis treatment — There is no cure for NASH. Treatment aims to control the conditions that are associated with NASH such as obesity, diabetes, and hyperlipidemia.
Weight loss — Weight reduction can help to reduce levels of liver enzymes and insulin.
Treatment of insulin resistance — Several drugs are available for people with insulin resistance, and they are being studied in patients with NASH.
Vitamin E — For people with severe forms of NASH who do not also have diabetes or heart disease, healthcare providers sometimes recommend supplements of vitamin E.
Miscellaneous drugs — Several new drugs are being tested in patients with NASH and are currently being studied in clinical trials.
For further information contact your Gastroenterologist or Family physician.
Dr. Gary F. Ciambotti is a senior partner at Digestive Health Care in Hillsborough, NJ. He has over 25 years’ experience in healthcare and is board certified by the American Board of Internal Medicine in Gastroenterology.