Hepatobiliary Flashcards
Brown pigment stones typically arise secondary to what?
Infection of the biliary tract
What enzyme is typically involved in the formation of brown pigment stones?
Injured hepatocytes and bacteria release beta-glucuronidase which contributes to the hydrolysis of bilirubin glucuronides - increasing the amount of unconjugated bilirubin in bile
What class of HIV drugs have a side effect of hyperglycemia?
Protease inhibitors (e.g. idinavir)
What does gallbladder hypomotility often lead to?
Bile precipitation and the formation of biliary sludge
Normal blood sugar levels, severe cardiomegaly, glycogen accumulation in lysosomes, normal glycogen structure - disease and enzyme deficiency?
Type II: Pompe’s disease - deficiency of lysosomal acid alpha-glucosidase
Muscle glycogen phosphorylase deficiency, weakness and fatigue with exercise, little or no rise in blood lactate levels after exercise, high level of glycogen in muscles - disease and enzyme deficiency?
Type V: McArdle’s disease - deficiency of glycogen phosphorylase
Hepatomegaly, fasting hypoglycemia, lactic acidosis, hyperuricemia, hyperlipidemia, increased glycogen storage but normal structure - disease and enzyme deficiency?
Type I: von Gierke’s disease - deficiency of glucose 6 phosphatase
How is rectal drug administration different from oral drug administration in terms of bioavailability?
Rectal drug administration partially bypasses first pass metabolism - drained by superior, middle, and inferior rectal veins. While the superior goes to the liver, middle and inferior go straight to systemic circulation.
High intracellular NADH in the setting of hypoglycemia is suggestive of what?
Since NADH is a carrier of energy, it suggests that a fuel other than glucose is being metabolized (e.g. alcohol)
What blotting technique uses a double stranded DNA probe?
Southwestern - used for proteins that bind DNA
What are some examples of DNA binding proteins (i.e. what you would use a southwestern blot for)?
Transcription factors (e.g. c-Jun and c-Fos), nucleases, histones
Toxicity of what drug is treated by donation of sulfhydryl groups?
Acetaminophen - treated with N acetylcysteine
How does acute hepatitis A typically present?
Fever, dark urine, malaise, nausea, vomiting, mild abdominal pain with hepatomegaly and jaundice
What is the function of acyl CoA dehydrogenase?
First enzyme in the series of reactions that breaks down acyl CoA to ketone bodies (beta oxidation) once it is brought into the mitochondria by the carnitine shuttle
Why are pregnant women at increased risk of gallstones?
Estrogen-induced cholesterol hypersecretion and progesterone-induced gallbladder hypomotility
Which class of viruses obtain their envelope by budding through the host cell nuclear membrane rather than the plasma membrane?
Herpesviruses
Why does Hepatitis D need to coinfect with Hepatitis B?
Needs viral coat (from Hepatitis B) before it can infect hepatocytes and multiply
Why is Hepatitis C genetically unstable?
Lacks proofreading 3’ to 5’ exonuclease activity
Acute inflammation of the gallbladder is initiated 90% of the time by?
Gallbladder outflow obstruction
Cardiac arrhythmia, hepatomegaly, dark skin (hyperpigmentation) - diagnosis?
Hemochromatosis
What are the 3 ketone bodies?
Acetone, acetoacetic acid, beta-hydroxybutyric acid
What causes spider angiomata?
Hyperestrinism
How does Hepatitis B replicate?
Double stranded DNA –> Template + RNA –> Progeny double-stranded DNA
What is the significance of prokaryotic 16S rRNA sequence?
Found in the 30s ribosomal subunit and contains a sequence complementary to the Shine Dalgarno sequence on mRNA - by allowing mRNA to bind to the ribosome, it initiates protein translation for prokaryotes
The most common form of galactosemia results from deficiency of what enzyme?
Galactose-1-phosphate uridyl transferase
Why is effective immunity against infection often not conferred for Hepatitis C?
Remarkable variety in the antigen structure of the envelope protein
What is a major gallbladder complication in the hospitalized/severely ill?
Acute acalculous cholecystitis - inflammed and enlarged gallbladder without gallstones
What is the most common malignant hepatic lesion?
Metastasis from another primary
What nutritional deficiencies do we worry about with prolonged cholestasis?
Fat soluble vitamins (A, D, E, K)
Why would someone with cholestasis get osteomalacia?
Vitamin D deficiency (Vitamin D is a fat soluble vitamin)
What does an acidophilic body signify in a hepatocyte?
Apoptosis from viral hepatitis - also called Councilman bodies and apoptotic bodies
What is the inheritance pattern of classic galactosemia?
Autosomal recessive
Presentation: 3 week old infant with persistent jaundice, dark urine, acholic stools, conjugated hyperbilirubinemia - diagnosis?
Biliary atresia
Neurologic symptoms with hepatic damage (elevated liver enzyme) should make you suspicious of what?
Wilson disease
What is one of the fastest/easiest diagnostic tools for Wilson disease?
Look for Kayser-Fleischer rings with slit lamp examination
What happens to BUN in liver disease?
Typically decreased because less ammonia is converted to urea
A moderately elevated alkaline phosphatase of unknown etiology should be followed up with by what test to check for liver disease?
Gamma-glutamyl transpeptidase - more specific for hepatocytes and biliary epithelia
Describe the series of reactions by which the liver is able to use the breakdown products of triglycerides.
- Triglycerides broken down into glycerol and fatty acids (fatty acids go on to beta oxidation)
- Glycerol goes to the liver where it is converted to glycerol 3-phosphate by glycerol kinase
- Glycerol is converted to DHAP which can be broken down into energy (via glycolysis) or glucose (gluconeogenesis)