Non-Alcoholic Fatty Liver Disease (NAFLD) and Nonalcoholic Steatohepatitis (NASH)
One of the most common causes of chronic hepatitis is accumulation of excess fat in the liver of people who do not drink excessive amounts of alcohol. The condition develops gradually, typically over several years, with the intake of too many calories. Sometimes, the first sign is abnormal results on routine blood tests. A liver biopsy may be ordered in cases where the liver is enlarged and viral or other causes of hepatitis have been ruled out. If the biopsy reveals that liver tissue is excessively fatty, inflamed, and showing signs of damage, the condition is called Nonalcoholic Steatohepatitis (NASH). If a fatty liver is otherwise healthy and showing no signs of inflammation or scarring, the condition is called Non-Alcoholic Fatty Liver Disease (NAFLD). NASH can be severe and can lead to cirrhosis in the liver. NAFLD typically causes no harm.
These conditions are most commonly seen in people with metabolic syndrome, a combination of health problems such as obesity (especially too much fat in the belly), hypertension, high triglyceride levels, low HDL cholesterol, and insulin resistance or type 2 diabetes. Currently, there is no specific treatment for either condition; however, those affected are typically encouraged to reduce their weight by increasing physical activity and following a healthy diet.
Signs and Symptoms
Usually, there are no apparent signs or symptoms of hepatitis caused by non-alcoholic fatty liver disease. When present, they are generally mild but may also correspond to those of hepatitis in general. See the section on Signs and Symptoms for detailed information.
A fatty liver may first be detected when routine tests such as a comprehensive metabolic panel (CMP) or a liver panel are performed for other reasons. Abnormal results on these may be the first indication that there is a problem with the liver. Imaging tests such as a CT scan or MRI may detect some fat in the liver. Often, several laboratory tests are done to rule out other causes, such as alcohol or hepatitis C. However, there are no laboratory tests that can make the diagnosis of NAFLD or NASH other than a liver biopsy.
There is no specific treatment for non-alcoholic fatty liver disease. There are some things that can be done that often lead to improvement in the condition of the liver: