Because nonalcoholic fatty liver disease causes no symptoms in most cases, it frequently comes to medical attention when tests done for other reasons point to a liver problem. This can happen if your liver looks unusual on ultrasound or if you have an abnormal liver enzyme test.

Tests done to pinpoint the diagnosis and determine disease severity include:

Blood tests

  • Complete blood count
  • Liver enzyme and liver function tests
  • Tests for chronic viral hepatitis (hepatitis A, hepatitis C and others)
  • Celiac disease screening test
  • Fasting blood sugar
  • Hemoglobin A1C, which shows how stable your blood sugar is
  • Lipid profile, which measures blood fats, such as cholesterol and triglycerides

Imaging procedures

Imaging procedures used to diagnose nonalcoholic fatty liver disease include:

  • Plain ultrasound, which is often the initial test when liver disease is suspected.
  • Computerized tomography (CT) scanning or magnetic resonance imaging (MRI) of the abdomen. These techniques lack the ability to distinguish nonalcoholic steatohepatitis from nonalcoholic fatty liver disease, but still may be used.
  • Transient elastography, an enhanced form of ultrasound that measures the stiffness of your liver. Liver stiffness indicates fibrosis or scarring.
  • Magnetic resonance elastography, which combines magnetic resonance imaging with patterns formed by sound waves bouncing off the liver to create a visual map showing gradients of stiffness throughout the liver reflecting fibrosis or scarring.

Liver tissue examination

If other tests are inconclusive, your doctor may recommend a procedure to remove a sample of tissue from your liver (liver biopsy). The tissue sample is examined in a laboratory to look for signs of inflammation and scarring. A liver biopsy may be painful in some patients, and it does have small risks that your doctor will review with you in detail. This procedure is performed by a needle insertion through the abdominal wall and into the liver.

Photograph of doctor viewing a magnetic resonance elastogram

A Mayo Clinic radiologist views an image obtained via magnetic resonance elastography (MRE) of the liver, showing areas of scarring (fibrosis) in red.

Aug. 23, 2016
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