Chronic liver disease, alcohol liver disease Flashcards
Alkaline phosphatase (ALP)
Enzyme mainly found in liver and bone- smaller amounts in kidneys and digestive system.
Used as a biomarker for hepatic obstruction.
When raised: could indicated liver or bone disease.
- To excluded bone, Gamma glutamyltransferase (GGT) test is used.
Gamma glutamyltransferase (GGT)
Enzyme used as a biomarker for liver function.
When elevated with ALP- indicates biliary obstruction
Alanine transaminase (ALT)
Enzyme most commonly found in the liver.
Ratio with AST used as an indicator for liver function.
Elevated ALT is a hallmarker for hepatitis
Alcohol dehydrogenase polymorphism
Alcohol dehydrogenase have several isoforms which vary in activity- genetic
This causes differences in metabolism of ethanol.
- B2 ADH isoform in Asian is 20x faster
Methanol metabolism
Methanol —-> Formaldehyde
- Using alcohol dehydrogenase
Formaldehyde —-> Formic acid
- Using aldehyde dehydrogenase
Formic acid—> carbon dioxide and water
- Using folate
- Build up of formic acid can cause blindness
Antifreeze poisoning
Caused by ingesting ethylene glycol
Ethylene glycol is eventually broken down to oxalic acid and glycolic acid= toxic
Oxidant stress caused by alcohol
Alcohol increases lipid peroxidation = acute tissue damage and fibrosis
- Generation of free radicals—> mutates DNA
Ethanol legal limit for driving
= 80mg/dL
less than/ = 2-3 units in females, 3-4 units in males
Alcoholic ketoacidosis
Anion gap metabolic acidosis.
Increased lipolysis and ketosis causes acidosis due to increases NADH/NAD ratio
- Gluconeogenesis is inhibited and insulin is suppressed.
Endocrine effects of alcohol
Decreased testosterone
Pseudo Cushings
Dsylipidaemia
Metabolic syndrome
AST
Aspartate transferase
Enzyme used as a biomarker for liver function
- Ratio compared with ALT
Elevated levels= liver damage
Globulin
Proteins that are found elevated in serum in liver cirrhosis.
INR
International normalised ratio.
Used as an indicator of clotting factors for liver function.
INR is increased in liver failure
Albumin
Protein synthesised by the liver.
Binds to many substances in the blood including water, cations, drugs, fatty acids.
When levels are low, indicates chronic liver disease like cirrhosis
Alcohol and thiamine deficiency
Causes deficiency in B1 due to:
- Interference with GI absorption
- Causing hepatic dysfunction which hinders storage and activation of B1.
- Malnourishment due to lack of food intake.
