Understanding Your MASH Test Results

If you’ve been diagnosed with metabolic dysfunction-associated steatohepatitis (MASH) (originally called non-alcohol-related steatohepatitis, or NASH), your doctor may have used a variety of tests to determine your diagnosis.

But what do MASH test results mean for your liver health?

Gastroenterologist and transplant hepatologist Sobia Laique, MD, explains what tests you may undergo to help detect MASH and what they may show.

Testing for MASH

MASH is a condition where excessive fat accumulates in your liver cells, causing inflammation, cell injury and cell death. Unlike how colonoscopies help screen for colon cancer and lipid panels are used to measure high cholesterol, there isn’t one universal, stand-alone test for MASH.

“Over the past few years, we’ve determined the optimal way to screen people for MASH is a two-step strategy,” explains Dr. Laique.

Fibrosis-4 index

The first step is calculating your fibrosis-4 index (or FIB-4), which determines your risk of having liver fibrosis from MASH. Your healthcare provider can use routine bloodwork, typically done during your annual exam. Your FIB-4 index is calculated using your:

• Platelet count
• Alanine transaminase (ALT) levels
• Aspartate transferase (AST) levels 
• Age

High levels of ALT and AST, which are both liver enzymes, may be a sign of liver inflammation and damage.

A FIB-4 index can range from:

• Less than 1.3: Low risk

To:

• 1.3 or higher: Intermediate to high risk

“If your FIB-4 index is 1.3 or higher, your healthcare provider will then order a test called vibration-controlled transient elastography (FibroScan®),” says Dr. Laique.

Vibration-controlled transient elastography

This specialized test helps assess the degree of fat buildup (mild, moderate or severe) and the degree of liver stiffness, which corresponds to the amount of scarring (fibrosis) in your liver. It’s a quick and painless test performed in a medical office.

“Liver stiffness is used to determine if MASH has caused any scarring (fibrosis) in the liver,” explains Dr. Laique. “This strategy of the FIB-4 index, followed by an elastography, allows us to narrow down and identify the most high-risk people who need treatment.”

It’s important to note that a Fibroscan isn’t exact, but it gives your doctors a ballpark assessment.

“Your healthcare provider may order further testing like an MRE/PDFF or in certain cases a liver biopsy to help guide your treatment plans,” she adds.

The level of scarring can range from mild to advanced:

• F0 to F1: None or mild scarring
• F2: Moderate scarring
• F3: Severe scarring
• F4: Advanced scarring, synonymous with the development of liver cirrhosis

Other tests used to determine MASH stage

Your doctor may also suggest additional tests to further clarify or determine the level of liver scarring. They may include:

• Magnetic resonance elastography and proton density fat fraction (MRE-PDFF): This specialized MRI calculates liver fibrosis and fat.
• Liver biopsy: A small sample of your liver is removed to be studied under a microscope. It accurately determines the cause of the liver disease in case of any diagnostic uncertainty and the degree of scarring — and helps your doctor formulate an appropriate treatment plan.

“The most common liver diseases in the U.S. are alcohol-related liver disease, metabolic dysfunction-associated steatotic liver disease (MASLD), followed by chronic hepatitis B and C,” points out Dr. Laique. “It’s not uncommon that you may have one of these along with MASH.”

Key takeaways

As we continue to learn more about MASH and how best to screen for it, don’t hesitate to talk to your doctor if you’re concerned about your liver health. Potential comorbidities like obesity, Type 2 diabetes or a family history of liver disease may increase your risk.

“There’s increasing recognition of MASH. Most primary care providers, endocrinologists and obesity specialists are proactively screening for it,” says Dr. Laique. “But you can be your best advocate by talking to your doctor about any concerns.”