Could a Fatty Liver Cause Elevated Liver Enzymes?
Mar 28, 2011 | By
Suzanne Robin started writing professionally for the Wiley "Dummies" series in 2001. She has co-authored seven books for the series and acted as developmental editor for several more. She has also worked as a registered nurse in oncology, labor/delivery, neonatal intensive care, infertility and ophthalmology. Robin received her registered nursing degree from Western Oklahoma State College.
Fatty liver, which is an accumulation of triglycerides--a type of fat--inside the liver, occurs in a number of disease processes. Fatty liver disease that causes liver damage is divided into two types: alcoholic fatty liver, which occurs in people who abuse alcohol and non-alcoholic steatohepatitis, also called NASH.
Sometimes NASH is called non-alcoholic fatty liver disease. Between 2 to 5 percent of Americans have NASH, and another 10 to 20 percent have fatty liver. The main cause of NASH and fatty liver is obesity. Elevated liver enzymes often reveal liver disease in people who feel well.
Types
The blood tests normally done to assess liver function include two enzymes, alanine aminotransferase, also called ALT, and aspartate aminotransferase, or AST. Both ALT and AST are found in cells outside the liver, but ALT is found mostly in the liver and kidney while AST is also found in the heart and skeletal muscle, brain and pancreas.
Cause
Damage to the liver causes ALT and AST to leak into the blood in larger than normal quantities, but damage to other tissues can also cause elevated levels, particularly of AST, in the blood. But strenuous exercise can also raise AST levels three-fold and ALT by 20 percent. Liver enzymes also average 40 to 50 percent higher than normal in obese patients.
Classifications
Medical practitioners generally consider levels up to five times higher than normal to be a mild increase in liver enzymes. While NASH is the most common cause of mild elevations in liver enzymes, medications, viral hepatitis, autoimmune hepatitis and other disorders can also cause the rise. Liver enzymes 15 times higher than normal, over 1,000 International Units per liter normally occur in acute hepatitis, poisoning with acetaminophen or other toxic medications or decreased blood flow to the liver, also called ischemic liver or shock liver. Elevations 100 times higher than normal levels occur from medication overdose or ischemic liver injury.
Treatment
Treatment of fatty liver depends on the cause. Alcoholics must stop drinking to stop liver damage, while losing weight may help if you're overweight or obese. High cholesterol and triglyceride levels normally respond to medications such as statins, niacin or fibrates.
Considerations
If alcoholics stop drinking, fatty liver may reverse itself in as little as six weeks. Losing as little as 10 percent of your weight can help decrease fatty liver. While up to 40 percent of people who have hepatitis C have normal ALT levels they may still have ongoing infection and could benefit from treatment
References
- The Merck Manuals Online Medical Library: Fatty Liver
- MayoClinic.com: Non-Alcoholic Fatty Liver Disease
- Jackson-Siegelbaum Gastroenterology: Fatty Liver
- University of Pennsylvania: The Asymptomatic Patient with Abnormal Liver Function Tests
- University of Illinois Medical Center: Non-Alcoholic Fatty Liver Disease
- National Institute of Diabetes and Digestive and Kidney Disorders: Chronic Hepatitis C
