Fatty Liver Disease (Steatosis)

Key points

• • Fatty liver (steatosis) is the abnormal build-up of fat droplets inside liver cells, and it is the commonest liver abnormality.
• • The two big causes are drinking too much alcohol (alcoholic fatty liver) and the metabolic problems of obesity and diabetes (non-alcoholic fatty liver disease, now often called metabolic dysfunction-associated steatotic liver disease, or MASLD).
• • Fat alone is often reversible, but in some people it progresses to inflammation (steatohepatitis); Mallory-Denk bodies may be seen but are not specific to it.
• • Ongoing inflammation lays down scar tissue (fibrosis), which over years can progress to cirrhosis and its complications.
• • Non-alcoholic fatty liver disease is now very common and is closely tied to the same problems as heart disease: obesity, diabetes and abnormal blood fats.
• • The liver is enlarged and pale, and the diagnosis is supported by imaging and, when needed, a liver biopsy.