Fatty liver refers to the infiltration of triglycerides and other fats into the liver cells, causing abnormal liver tests, inflammation and possibly permanent liver damage when left untreated. Because of improved imaging tests and frequent blood testing, fatty liver is now being diagnosed more frequently and non-alcoholic steatohepatitis (NASH), a form of fatty liver, has become the third most common liver disease in U.S. adults who are evaluated for increased liver enzymes.

While patients don't usually experience symptoms from fatty liver, it can be detected through an ultrasound or CT scan and by elevation in liver chemistries. Occasionally, patients may experience a dull pain in the right upper abdomen or fatigue. To make an absolute diagnosis, a liver biopsy is performed.


What are the types of fatty liver?
There are three types of fatty liver. If a biopsy shows liver inflammation and scar tissue, or if fibrosis has occurred, steatohepatitis is diagnosed. Steatohepatitis may be associated with alcohol use, but if the liver damage is unrelated to alcohol, the condition is called non-alcoholic steatohepatitis (NASH). Fatty liver without inflammation is referred to as steatosis.

What causes fatty liver?
Fatty liver is most commonly associated with obesity and in some people, even a small amount of excess body fat can increase the amount of fat stored in the liver. Under normal conditions, fat from the diet is metabolized by the liver and other tissues. If the amount of fat exceeds the body's requirement, abnormal fat accumulations may develop in the liver, causing an increase in liver enzymes and inflammation. This inflammation can cause scarring and hardening of the liver (cirrhosis) and results in decreased liver function.

While obesity is a major contributor to fatty liver, other causes include Hepatitis C virus, Wilson's disease, medications, chemical compounds, poor nutrition, hyperlipidemia or endocrine disorders. Specific medications and substances that can cause fatty liver include alcohol, amiodarone, methotrexate, high doses of vitamin A, tetracycline, cortisone, phosphorus, prednisone and carbon tetrachloride. Of these substances, alcohol is by far the most common cause of fatty liver and even as little as one glass of wine or beer a week may contribute to this condition.

Can fatty liver be easily identified?
Fat in the liver does not produce symptoms in some patients because it is deposited slowly and few side effects are felt. When the fat content increases rapidly, the liver expands and the membrane stretches, resulting in abdominal pain.

How does fat enter the liver?
Fat enters the liver through diet, the blood stream and from fat stored in fatty tissue. Under normal conditions, fat from the diet is usually metabolized by the liver and other tissues. If the amount of fat exceeds the body's requirement, it is stored in the fatty tissue. Eating fatty foods produces a fatty liver indirectly by increasing circulating fats in the blood stream and enhancing obesity.

Can fatty liver cause other liver diseases?
Fatty liver can be present in patients with alcoholic hepatitis and cirrhosis or may be an isolated finding. Current findings show that while fatty liver is usually present during excessive alcohol intake, it probably does not lead to the development of alcoholic hepatitis or cirrhosis. In fact, most individuals with alcoholic fatty liver do not develop the more serious forms of liver diseases. Continued alcohol ingestion, however, has been known to cause alcoholic hepatitis and cirrhosis. Fatty liver has now been produced in primates after four years of alcohol ingestion. It may take even longer liver humans.

How is fatty liver treated?
Treatment of fatty liver is determined based on the cause of the disease. Typically, fat is decreased by removing the chemical compound or drug that is causing fatty liver. Nutritional causes are treated by altering the availability of fat that enters the liver. This is accomplished by providing available carbohydrates or by adding protein to overcome complete or large deficiencies. Proteins are used to make lipoproteins to carry cholesterol and fats. L-carnitine dose of 340 mg twice a day, lecithin and choline are also choices.

How can I avoid fatty liver?
To avoid fatty liver, patients should follow these general guidelines:

• Follow a low-fat and low-cholesterol diet
• Exercise regularly to maintain an ideal weight
• Do not drink alcohol to excess
• Review medications to ensure that they aren't hepatotoxic (toxic to your liver)
• Have blood sugar, cholesterol and triglyceride levels checked regularly

Should I undergo a liver biopsy?
Patients with fatty liver have a small chance of developing cirrhosis. If there is inflammation with the fat, there is a 7% to 20% chance of developing cirrhosis. A liver biopsy is the best way to determine the presence of inflammation. If inflammation exists, patients should first try weight loss and then undergo a liver biopsy if excess pounds can't be shed or the liver tests do not improve.

Are there other tests that can help with the diagnosis of fatty liver?
An ultrasound or CT scan can suggest fatty liver but the only way to make an absolute diagnosis is a liver biopsy. A trial of weight loss and a low fat diet also aid in the diagnosis of fatty liver since almost all patients will show improvement in lowering liver enzymes with weight loss and diet control.

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