Nonalcoholic fatty liver disease (NAFLD) affects over 1/4th of the world’s population. It has become the leading cause of cirrhosis in developed western countries. NAFLD and NASH exist along a spectrum.
NAFLD: Patients are usually asymptomatic and the condition is found incidentally. It is defined as: >5% of hepatic steatosis in patients who do not consume excessive alcohol. They will not have hepatocellular injury (∼80% of patients have normal-range ALT levels).
Approximately 10–30% will progress to non-alcoholic steatohepatitis (NASH). Which is differentiated by inflammation and hepatocellular injury (elevated ALT>AST). Its the active form of NAFLD, with hepatic necro-inflammation and faster fibrosis progression.
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