112b liver injury patterns Flashcards
Fatty liver disease - causes
1) NAFLD - non-accoholic –> silent and progressive; fat people, DM
2) AFLD - alcoholic (>20g/day)
FLD - sequence of disease
1) hepatic steatosis (fatty liver)
2) steatohepatitis - inflammation and mallory bodies
3) fibrosis/cirrhosis
4) liver cancer
liver role in energy storage
adipocytes are overwhlemed so liver stores fat leading to steatosis
hepatic steatosis
short-term, reversible change
macrovesicular fatty change (micro = reye’s)
alcoholic hepatitis
-Sustained, long-term consumption.
-Swollen and necrotic hepatocytes with
neutrophilic infiltration (lipogranulomas); excess long-chain FFA –> apoptosis
-Mallory bodies (intracytoplasmic eosinophilic inclusions) are present.
alcoholic cirrhosis
-Final and irreversible form.
-Micronodular, irregularly shrunken liver with “hobnail” appearance.
-Sclerosis around central vein(zone III).
-Has manifestations of chronic liver
disease (e.g., jaundice, hypoalbuminemia).
defective PPARa sensing
leads to fatty liver (fat sensor in the liver)
PPAR gama function
adipogenesis and energy conservation (makes you fat)
what part of alcohol causes damage?
acetaldehyde (metabolite) - also causre vasodilation, flushing, low blood pressure, sweating, palpitations
what causes liver damage (type of drinking)
chronic, slow and steady - not binge drinking
metabolism of alcohol
oxidative process
ethanol –> acetaldehyde –> acetate via
1) ADH/ALDH2 system (ALDH2 fast in asians, some can’t metabolize acetald so protective)
2) CYP2E1 (ROS generation leading to damage in liver)
3) peroxisomal catalase
stellate cells
proliferate and causes fibrosis in liver with AFLD from ROS and acetaldehyde
types of hepatic fibrosis
Perivenular Fibrosis: Surrounding central veins
Pericellular Fibrosis: Circling single or groups of liver cells
Perisinusoidal Fibrosis: Within the sinusoids and space of Disse
