Medical professionals commonly rely on blood tests to screen for liver disease. Liver function tests measure the levels of enzymes and other blood chemicals. The results of these tests help doctors assess the overall health of the liver. Many liver diseases and conditions can cause elevated liver function tests. Determining the underlying cause of elevated liver function tests serves as the initial step in developing a treatment strategy.
Alcoholic Liver Disease
Protracted, heavy alcohol consumption can cause liver disease and elevations in the liver function tests. Alcohol detoxification occurs primarily in the liver. Regular, heavy drinking can cause changes in liver chemistry that lead to an accumulation of fat in the liver cells and inflammation. This condition, known as alcoholic hepatitis, develops in approximately 20 percent of heavy drinkers, reports the Cleveland Clinic. Continued drinking in a patient with alcoholic hepatitis frequently leads to cirrhosis. The Centers for Disease Control and Prevention reports that approximately 14,400 Americans died of alcoholic liver disease in 2007.
Nonalcoholic Fatty Liver Disease
Nonalcoholic fatty liver disease describes a group of liver conditions characterized by an abnormal accumulation of fat in the liver among patients who drink little or no alcohol. Elevated liver enzyme levels may occur with these conditions. Nonalcoholic fatty liver disease typically occurs in overweight or obese patients with elevated blood fats and diabetes or prediabetes. Up to 20 percent of adults and 5 percent of children in the United States have nonalcoholic fatty liver disease, estimates the American College of Gastroenterology. In some patients, fat in the liver cells progresses to inflammation, or nonalcoholic steatohepatitis. This condition may lead to cirrhosis and liver failure.
Viral Hepatitis
The hepatitis A, B and C viruses remain the most common causes of viral hepatitis among American children and adults. Each of these viruses can cause acute liver inflammation, often associated with elevated liver enzymes levels. Infection with the hepatitis B and C viruses may lead to persistent liver inflammation, or chronic hepatitis. Patients with chronic viral hepatitis may develop extensive liver scarring, cirrhosis and liver failure. The Centers for Disease Control and Prevention estimates that 1.2 million Americans are living with chronic hepatitis B, and 3.2 million have chronic hepatitis C.
Medications, Supplements and Herbs
Several medications, nutritional supplements and herbs can cause elevated liver enzyme levels. In a March 2005 article published in "American Family Physician," Dr. Paul Giboney notes that medicinal substances commonly associated with elevated liver function tests include sulfonamide antibiotics, nitrofurantoin, amoxicillin-clavulanic acid, protease inhibitors, labetolol, amiodarone, ibuprofen, acetaminophen, glyburide, phenytoin, carbamazepine, ephedra, shark cartilage, chaparral leaf, kava, gentian, scutellaria and excessive vitamin A.
Discontinuing nonessential medicinal substances typically leads to correction of the elevated liver function tests. For patients who require ongoing therapy, changing to a less liver-toxic drug often corrects the liver enzyme elevation.
References
- Cleveland Clinic: Alcoholic Liver Disease
- Centers for Disease Control and Prevention: FastStats, Alcohol Use
- American College of Gastroenterology: Fatty Liver Disease
- Centers for Disease Control and Prevention: The ABCs of Hepatitis
- "American Family Physician"; Mildly Elevated Liver Transaminase Levels in the Asymptomatic Patient; Paul T. Giboney, M.D.; March 2005
