Liver Disease B&B Flashcards
where in the cell do AST vs ALT function, and what is the clinical significance of this?
AST = aspartate aminotransferase, located in mitochondria… AST>ALT in alcoholic hepatitis bc alcohol is mitochondrial toxin
ALT = alanine aminotransferase, located in cytosol… ALT>AST in most types of hepatitis
what is the clinical use of measuring levels of gamma-glutamyl transpeptidase (GGT)?
GGT is similar to alkaline phosphatase (Alk Phos), but is NOT elevated in bone disease (while Alk Phos may be) —> used to determine source of Alk Phos elevation
elevated GGT + Alk Phos = hepatobiliary cause of elevated Alk Phos
GGT is also elevated after heavy alcohol consumption
which liver pathology affects Zone I more than Zone III?
portal triad (hepatic artery + bile duct + portal vein) —> Zone I (periportal) —> Zone II (midzone) —> Zone III (centrilobular) —> hepatic vein
most liver diseases affect Zone III the most (alcoholic liver disease, cirrhosis, etc), except viral hepatitis which affects Zone I (more because this is the first area it encounters)
how can liver function tests be used to distinguish alcoholic fatty liver disease from non-alcoholic fatty liver disease (NAFLD)?
alcoholic hepatotoxicity: AST>ALT because ALT functions in mitochondria, and alcohol is mitochondrial toxin
NAFLD: ALT>AST, as with most liver disease
alcoholic hepatitis presents with fever, jaundice, and RUQ pain following binge drinking (on top of chronic alcohol use) due to toxic effects from ______
alcoholic hepatitis presents with fever, jaundice, and RUQ pain following binge drinking (on top of chronic alcohol use) due to toxic effects from ACETALDEHYDE
what does biopsy show in alcoholic hepatotoxicity?
Mallory bodies: cytoplasmic inclusions of intermediate filaments
looks like a eosinophilic (pink) twisty structure in periphery
of what are Mallory bodies a sign?
Mallory bodies: cytoplasmic inclusions of intermediate filaments that occur in alcoholic liver disease
looks like a eosinophilic (pink) twisty structure in periphery
Budd Chiari Syndrome
thrombosis of hepatic vein causes congestion/necrosis/hemorrhage of Zone 3 (near hepatic vein)
—> abdominal pain, ascites, hepatomegaly, mottled (“nutmeg”) liver
causes: myeloproliferative disorders, hepatocellular carcinoma, OCP/pregnancy, hypercoagulable states
what is the gross appearance of “cardiac cirrhosis” (liver failure caused by right heart failure)?
nutmeg liver - mottled
with which 2 infections is Reye’s syndrome most closely associated?
Reye’s syndrome: rare liver failure + encephalopathy in children with viral infections taking aspirin
classically infections with varicella zoster (chicken pox) or influenza B
what is the one case in which aspirin administration in children is appropriate?
avoid due to Reye’s Syndrome: liver failure + encephalopathy in children taking aspirin (inhibits beta oxidation)
however, still used in children with Kawasaki’s vasculitis because it was found to be really effective
what is the genetic pattern of alpha1 anti-trypsin deficiency inheritance?
autosomal co-dominant - decreased or dysfunctional alpha1 anti-trypsin (balances out natural proteases in lung)
how does alpha1 anti-trypsin deficiency affect the liver?
buildup of abnormal polymerized alpha1 anti-trypsin in the endoplasmic reticulum of hepatocytes causes cirrhosis
what histological stain can be used to diagnose alpha1 anti-trypsin deficiency?
AAT polymers can be visualized in lung or hepatocytes with PAS staining
name a classic cause of liver abscess in each category:
a. bacterial via cholangitis (ascending from intestines)
b. protozoa
c. helminth
a. bacterial via cholangitis - Klebsiella
b. protozoa - Entameba histolytica (cysts in contaminated water, ascends biliary tree)
c. helminth - Echinococcus (fecal-oral egg ingestion, HUGE abscesses)
