Nonalcoholic fatty liver disease
- Descriptions
- NAFLD: non-alcohol related accumulation of fat in the liver cells
- NASH: NAFLD with chronic inflammation and damage of liver cells
- Epidemiology: very widespread
- Etiology
- Obesity and/or type 2 diabetes (metabolic syndrome)
- Due to excess supply of nutrients in the liver
- Obesity and/or type 2 diabetes (metabolic syndrome)
- Pathophysiology: ↑ Insulin resistance
- ↑ Hepatic uptake of fatty acids
- Essentially, insulin resistance creates a situation where fat storage in the designated areas (fat cells) is impaired, causing the liver to take on an excess burden of processing these fatty acids.
- ↑ Triglyceride synthesis
- ↑ Peripheral lipolysis
- ↑ Hepatic uptake of fatty acids
- Clinical features
- Often asymptomatic
- Hepatomegaly
- May progress to cirrhosis
- Diagnostics
- ↑ Transaminases (AST/ALT ratio < 1): The reversal of the AST/ALT ratio to values > 1 may indicate progression to cirrhosis.
- Rule out other causes of chronic hepatitis (e.g., heavy alcohol use, hepatitis B, hepatitis C, Wilson disease, autoimmune hepatitis, hemochromatosis, α1-antitrypsin deficiency)
Mnemonic
There is more ALT than AST (AST/ALT < 1) if the Liver is infiltrated with Lipids.
- Pathology
- Hepatocellular lipid accumulation, mostly macrovesicular