Chapter 18- The Liver Flashcards
What are the functions of the liver?
Glycogen storage
Toxin removal
Nutrient processing
Nutrient storage (Vit A and iron)
Cholesterol, albumin and clotting factor production
Alcohol and drug metabolism
Bile production
What is the function of bile?
Major excretory route for exogenous lipophilic substances and endogenous substrates not readily excreted by the kidney
Cholesterol elimination
Excretion of IgA, cytokines, stimulates innate immune system
Hormone and pheromone excretion
Bile salts emulsify dietary fats
What reversible changes can occur in the liver?
- Steatosis (fat accumulation)
2. Cholestasis (bilirubin build up)
How do liver scars form and regress?
Stellate cells are activated and converted to fibrogenic myofibroblasts (cytokines)
Conversion reversed if insult stops
Metalloproteinases from hepatocytes break down scar
What is associated with acute liver failure?
Encephalopathy
What is fulminant hepatic failure?
Encephalopathy within two weeks of jaundice
What are the characteristics of acute liver failure?
Massive hepatic necrosis
Small and shrunken liver
Nausea, vomiting and jaundice
Reduced clotting factors
Portal hypertension
What is responsible for about 50% of acute liver failure?
Acetaminophen
What is hepatorenal failure?
Form of renal failure in patients with liver failure
What are causes of chronic liver failure?
Alcohol abuse
Viral hepatitis
Nonalcoholic steatohepatitis
What is the morphology of cirrhosis?
Regenerative nodules surrounded by fibrous bands and degrees of vascular shunting
What are the characteristics of chronic liver failure?
Jaundice
Encephalopathy
Coagulopathy
Intense pruritis
Spider angiomas
Hyperestrogenemia
What causes death in chronic liver failure?
Hepatic encephalopathy
Bleeding from esophageal varices
Bacterial infections
Hepatocellular carcinoma
What is portal hypertension?
Increased flow and/or resistance to portal blood flow
What are the three types of portal hypertension and what can cause them?
- Prehepatic- obstructive thrombosis, portal vein narrowing and massive splenomegaly with increased splenic vein flow
- Intrahepatic- cirrhosis, schistomiasis, massive fatty change, granulomatous disease, nodular regenerative hyperplasia
- Posthepatic- RSHF, constrictive pericarditis or hepatic vein obstruction
What is acute on chronic liver failure?
Acute liver failure that has developed in patients with stable but advanced chronic liver disease
What are the different kinds of hepatitis and their characteristics?
Hep A- damage due to CD8 cells, fecal-oral
Hep B- acute and nonprogressive chronic hepatitis, acute hepatic failure, damage due to CD8 cells, vertical and horizontal transmission
Hep C- often progresses to chronic disease, horizontal transmission
Hep D- dependent on HBV infection (superinfection), progression to cirrhosis
Hep E- enterically transmitted, self limiting, fatal in pregnant women
What forms of hepatitis can increase hepatocellular carcinoma?
Hep B
Sometimes Hep D
What types of hepatitis have vaccines available?
Hep A and B
How can extrahepatic infections affect the liver?
Can induce hepatic inflammation
What is the morphology of parasitic infections in the liver?
Hepatic abscesses
What type of autoimmune hepatitis is autoimmune hepatitis?
Chronic and progressive
What is the most common hepatotoxic causing chronic liver disease?
Alcohol
What are the forms of alcohol induced liver injury and their characteristics?
- Hepatocellular steatosis or fatty change- accumulation of lipid droplets, greasy liver
- Alcoholic (steato-) hepatitis- foci of cells that undergo swelling and necrosis, clusters of inflammatory cells, Mallory-Denk bodies, neutrophilic reactions
- Steatofibrosis- activation of stellate cells and portal fibroblasts, perisinusoidal scar accumulated and spreads outwards, cirrhosis in late stages
What are Mallory-Denk bodies?
Clumped eosinophilic material in the liver
What is Laennec/micronodular cirrhosis?
End stage alcoholic liver disease
Where does fibrosis begin in steatofibrosis?
Central vein sclerosis
What are the different types of metabolic liver disease?
Nonalcoholic fatty liver disease (NAFLD)
Hemochromatosis
Wilson disease
Alpha-1-antitrypsin deficiency
What is NAFLD?
Hepatic steatosis in the absence of heavy alcohol consumption
What is NAFLD associated with?
Metabolic syndrome
NAFLD increases the risk of what?
HCC
What do the hepatocytes in NAFLD look like?
Filled with fat vacuoles
What is the major cause of mortality?
CVD
What is hemochromatosis?
Excessive iron accumulation in the parenchymal cells of various organs
What are the forms of hemochromatosis?
- Hereditary
2. Hemosiderosis
What can cause hemosiderosis?
Repetitive transfusions
Ineffective erythropoiesis
Increased iron intake
Chronic liver disease
How is hemochromatosis treated?
Regular phlebotomy
How is hemochromatosis visualized?
Prussian blue stain
What is Wilson disease?
Impaired copper excretion
How does Wilson disease affect the liver?
Minor to severe damage
Fatty change, acute and chronic hepatitis