1. What is the definition of non-alcohol fatty liver disease?
1.5 What are the 3 types of NAFLD?
2. How is it diagnosed? (4)
3. What are the causes and complications? 10
1. NAFLD = spectrum of disorders that range from simple steatosis w/o inflammation to non-alcohol steatohepatitis (NASH) with fibrosis
1.5 Macrovescular fat in >5% hepatocytes in absence
of (1) significant ethanol, drug, toxin ingestion (2) viral hepatitis (3) inborn metabolic errors (4) cystic fibrosis/wilson's disease
fat without inflammation - steatosis (non-alcoholic) accumulation of fat in the liver, IC fat deposition.
- fat with inflammation --> fat deposits, inflammation, fibrosis with necrosis.
- 2. Diagnosis:
- - Mostly asymptomatic, primary problem is insulin resistance --> increased lipolysis, TG synthesis, hepatic uptake of FFA, increased hepatic TG
(1) Physical findings - liver function test elevation, fatigue, malaise, incidental finding/imaging
(2) Lab findings - ALT/AST 2-5x upper limit of normal, AST/ALT <1, ETOH>2, elevated ferritin, autoimmune markers
(3) Radiographic findings - cannot diff NAFL from NASH - sonogram, CT scan, MRIs, MR spectroscopy, ultrasound
(4) Biopsy - hepatocyte injury, ballooning, dead cells, inflammatory cell infiltration, fibrosis.
- 3. CAUSES: metabolic syndrome (central obesity, hypertension, dyslipidemia, insulin resistance/diabetes, accelerated atherosclerotic heart disease)
- TG accumulation, insulin resistance, hepatocellular injury, antioxidant depletion, increased hepatic iron, decreased production of leptin --> obesity, adiponectin (enhances plasma lipid clearance), resistin (overexpression leads to insulin resistance), intestinal microbes