Fatty Liver: please check ALT

Fatty liver is just accumulation of excess fat in the liver. It can be primary or secondary.

Primary (cause unknown)

• NAFLD (Non-Alcoholic Fatty Liver Disease)

Secondary (cause known)

• Alcohol
• Hepatitis B
• Hepatitis C
• Drugs-induced
• Wilson's disease
• Autoimmune hepatitis

    Fat cells (white) in the liver

NAFLD is a spectrum of diseases ranging from

• Simple fatty liver (steatosis)
• Fatty Liver with inflammation & fibrosis (NASH – Non-Alcoholic Steato-Hepatitis)
• Severe liver scarring/fibrosis (cirrhosis)

    Note the changes in liver size

The cause of NAFLD is not clearly known. However it is believed to be associated with insulin resistant, a condition that causes metabolic syndrome and type 2 diabetes mellitus. So, you probably have NAFLD if you have the following:

• Obesity/overweight
• Diabetes mellitus (type 2)
• High LDL-cholesterol
• Low HDL-cholesterol
• High triglycerides

Fatty liver has no specific symptoms in early stages. It is usually first suspected when people do blood test for whatever reason and find that their ALT (alanine transaminase) is raised. There are a few causes of raised ALT, which represent liver inflammation/injury. Doctors will rule out those causes such as drug-induced (esp cholesterol medicine) and viral hepatitis etc. If nothing can be found, ultrasound of the liver should be done to look for fatty liver. Ultrasound is a cheap, simple and accurate (though not 100%) method to diagnose fatty liver.

    Fatty liver on ultrasound, "more white" compare to the kidney

When fatty liver is confirmed via ultrasound, the next step is to find the cause of fatty liver. As mentioned earlier, the secondary causes such as alcohol, viral hepatitis etc need to be ruled out. If a cause of fatty liver is identified, we can treat that condition accordingly. But if no cause can be found, then we can call it NAFLD.

• NAFLD with normal ALT = simple fatty liver = harmless
• NAFLD with raised ALT = NASH = slight risk of progression to liver cirrhosis & subsequently liver cancer

The risk of liver cirrhosis in NASH is not well established, should be around 10%. However, it takes many years (>20 years) to progress from NASH to cirrhosis. Compared to NASH, cirrhosis usually occurs earlier in fatty liver caused by alcohol and hepatitis.

If your fatty liver is due to alcohol, you have to reduce or stop drinking. If it is due to viral hepatitis, you may need anti-viral treatment. Though there is no specific treatment for NAFLD, one can benefit from losing weight, lowering blood cholesterol/triglycerides/sugar through diet, exercise and sometimes medication. Control it before it is too late, as the liver damage will become irreversible (incurable) if it reaches cirrhosis stage.