Weight Loss Improves Liver Function in Steatohepatitis

Q:  I am a 53-year-old female who has had elevated liver enzyme levels for several years. After a recent liver biopsy, my doctor indicated a diagnosis of "steatohepatitis," which he described as "a mild fatty infiltration of the liver."

Can you tell me in layperson's terms what this means? Should I be concerned?

A:  Your doctor gave you a rough translation of the Latin steatohepatitis, meaning fat (steato) deposition and an inflammation of the liver (hepatitis).

A liver can become inflamed (that is, injured and irritated) for a number of reasons, commonly from alcohol, viruses (such as hepatitis A), and, in your case, an abnormal metabolism of sugar and cholesterol.

Nonalcoholic steatohepatitis or NASH is a common, often "silent" liver disease. It resembles alcoholic liver disease, but occurs in people who drink little or no alcohol. The major feature in NASH is fat in the liver, along with inflammation and damage. Most people with NASH feel well and are not aware that they have a liver problem. Nevertheless, NASH can be severe and can lead to cirrhosis, in which the liver is permanently damaged and scarred and no longer able to work properly.

NASH affects 2% to 5% of Americans. An additional 10% to 20% of Americans have fat in their liver, but no inflammation or liver damage, a condition called "fatty liver." Although having fat in the liver is not normal, by itself it probably causes little harm or permanent damage.

NASH is usually first suspected in a person who is found to have elevations in liver tests that are included in routine blood test panels, such as alanine aminotransferase (ALT) or aspartate aminotransferase (AST). When further evaluation shows no apparent reason for liver disease (such as medications, viral hepatitis, or excessive use of alcohol) and when x-rays or imaging studies of the liver show fat, NASH is suspected. The only means of proving a diagnosis of NASH and separating it from simple fatty liver is a liver biopsy.

While the exact cause of steatohepatitis is not clear, obesity and diabetes can be instigators.

Physician Walter Hogan, MD, a Professor of Medicine (Gastroenterology and Hepatology) at the Medical College of Wisconsin, tells me that steatohepatitis is one of the most rapidly growing liver problems in the country.

Yet, he said, most people with steatohepatitis do not develop frank liver failure and, in particular, the results of your liver biopsy are reassuring because you did not describe structural abnormalities of the liver, only the inflammation. Still, steatohepatitis progresses to cirrhosis in quite a few people (about 10% to 20% over the course of seven years).

The treatment for steatohepatitis consists of gradual weight loss to normal weight, physical activity, and control of diabetes (if present) and high cholesterol. Weight loss does improve liver function and reduce further liver injury.

Julie L. Mitchell, MD, MS, is an Assistant Professor of Medicine at the Medical College of Wisconsin. She practices internal medicine at the Froedtert & Medical College General Internal Medicine Clinic - East. Her column appears in the Milwaukee Journal-Sentinel.