2. Cell Injury Flashcards
What is the number 1 drug cause of fulminant hepatitis?
Acetaminophen - from free radical damage
Where in the liver does acetaminophen toxicity manifest?
Right around the central vein
What is the treatment for acetaminophen toxicity?
N-acetylcysteine
What is the neutralizer for superoxide?
Superoxide dismutase (SOD)
Where does glutathione come from?
HMP shunt (also generates NADPH)
What is glutathione’s main function?
Neutralize free radicals - especially anything that comes from peroxide
What does N-acetylcysteine do?
N-acetylcysteine is the substrate for glutathione –> body makes more glutathione –> can neutralize the free radicals from acetaminophen
How does leucovorin rescue work with methotrexate?
Leucovorin is a substrate for DNA so that body can overcome the block of dihydrofolate reductase?
How does acetaminophen affect the kidney?
Destroys the medulla (over years)
What are the enzymes involved in signaling of apoptosis?
Caspases
What organs would you expect to be pale with infarction?
Organs with good consistency - heart, kidney, liver, spleen
What organs would you expect to be hemorrhagic with infarction?
Organs with meshy consistency - lungs, testes, bowel
Where do most emboli in systemic circulation arise?
Left side of the heart
The arrythmia most associated with embolization in the systemic circulation is?
Atrial fibrillation (stasis of blood in the atria, clot, and then embolus)
Dry gangrene foot - problem where?
Diabetes in popliteal artery (atherosclerosis)
How do infarcts usually arise?
Lumen narrowing from atherosclerotic plaque (ischemia) then a thrombus
What is the most common cause of intestinal infarct?
Adhesions from previous surgery
What is the second most common cause of intestinal infarct?
Piece of bowel trapped in indirect inguinal hernia
What is the exception to coagulation necrosis underlying the infarction?
Brain - instead see liquefactive necrosis (cystic spaces)
What is analogous to the fibroblast in the brain?
Astrocyte
What cells mediate liquefactive necrosis?
Neutrophils (acute inflammation/infection) with the one exception being infarct in the brain
Why does staph tend to produce an abscess?
Coagulase - tends to localize the infection and neutrophils can’t get out
What is the most common cause of bronchopneumonia?
Strep pneumo
Where do we see infarction in the lung?
Periphery, wedge-shaped
What does caseating granulomas mean?
Mycobacteria or systemic fungal (the lipid in the cell wall gives it the cheese-like consistency)
Where does pancreatic inflammation radiate pain to?
Back
Where does peptic ulcer disease radiate pain to?
Epigastric
What kind of necrosis occurs in pancreatitis?
Fat enzymatic necrosis - unique to the pancreas
What does enzymatic necrosis look like?
Saponification - chalky white calcified areas (appear on X ray)
What color does calcium appear as?
Blue
Which one is more specific for the pancreas - amylase or lipase?
Lipase
What tends to be the underlying cause of enzymatic necrosis?
Alcoholism
What is fibrinoid necrosis?
Immunologic disease with necrosis that looks fibrin-like
What is palpable purpura?
Type III hypersensitivity, small vessel disease
How do you get damage in type III hypersensitivity?
Deposition of immune complexes –> activates complement –> C5a –> recruit neutrophils which are really what mediate the damage
When do we see nutmeg liver?
Right sided heart failure - congested liver
What happens to the liver if you block the portal vein?
Nothing - portal vein is before liver
What happens to the liver if you block the hepatic vein?
Congested liver
What part of the liver does yellow fever like to hit?
Zone 2
What part of the liver is most susceptible to injury?
Zone 3 - right around the central vein because it gets the least amount of oxygen (zone 1 gets the most oxygen from the sinusoids, then zone 2, and finally zone 3)
What’s the most common cause of fatty change in liver?
Alcohol (NADH and acetyl coA)
What acid base change do we tend to see in alcoholics?
Fasting hypoglycemia with lactic acidosis (pyruvate shunted to lactate) and ketoacidosis (lots of acetyl coA)
What’s the main ketone body?
Beta hydroxybutyrate
