Biochemistry Flashcards
How can you tell if someone is a chronic drinker from a blood test?
Raised GGT - LFT test
Increased mean cell volume
Raised triglycerides
More immature retinoblasts
Why is GGT raised by chronic alcohol use
Ethanol induces the P450 oxygenase enzyme to break it down and this will raise GGT
Why are triglycerides raised in chronic alcoholism
Increased synthesis of triglycerides in the level
What Is the normal level of triglycerides and what will it go up to in alcoholics
Should be between 2 and 3
In alcoholics it can rise to very high numbers, even 3 figures
Describe the effect of alcohol on major organs - liver, pancreas, muscles etc
Damages the liver
Effects how you metabolise glucose and can even lead to hypoglycaemia and coma
Damages pancreas - chronic alcoholics may present with acute or chronic pancreatitis
Toxic to muscles
May lead to alcoholic cardiomyopathy and heart failure
How do you determine how severe the unconscious state is
Use the Glasgow coma scale
How do you work out if a coma is caused by alcohol
Measure their serum osmolarity
An alcohol patient would have a large osmalol gap as the alcohol is affecting the levels
How do you calculate serum osmolarity
Measure the concentration of electrolytes in the serum
Na is always highest
Double the level of sodium and add 10
What is an osmalol gap
When there is a difference between the measured serum osmolarity and the one calculated from electrolyte levels
Seen in alcohol patients as electrolytes normal but osmolarity high
How can ABG’s be used to determine what alcohol has been consumed
If it is methanol or ethylene glycol then the bicarb will be very low
This is because both get metabolised to incredibly acidic compounds and create a huge acid load which messes up the balance
What type of patients will have methanol or ethylene glycol poisoning
Severe alcoholics
Suicidal people - drinking de-icer
Children - accidental
Describe ALT
Alanine aminotransferase
Found especially in the liver - in hepatocytes
Tells you about liver damage
What causes jaundice
Raised bilirubin
This can be caused by anything that increases haemolysis or a block in bile drainage
What is the difference between unconjugated and conjugated jaundice
Unconjugated - bilirubin hasn’t gone through the liver (prehepatic)
Conjugated - post-hepatic so caused by issue after the liver like blocked duct or tumour
Liver disease can cause both types
Describe ALP
Alkaline phosphate
Found in both the liver and bone
Also is proximal tubules of kidneys and small intestine
How do you determine whether raised ALP is from the liver or bone
Measure GGT at the same time
If it is also raised it is more likely to be liver
Describe albumin
Made in the liver
Marker of liver function
Can be affected by lots of thing so not as accurate
How can you determine of abdominal pain is caused by alcohol
Do LFT’s to check liver and gall bladder
Do amylase to see if it’s a pancreatitis caused by alcohol
What tests should you do if an alcoholic patient is vomiting
Measure U and E – creatinine will rise as they will lose fluid through vomit
LFT’s - check for liver damage
Amylase - check for pancreatitis
ABG - vomiting causes loss of H+ so end up with a metabolic alkalosis
Potassium will be low in severe vomitors
What is a potential consequence of repeated vomiting
Mallory-Weiss tear
Alcohol can cause repeated vomiting that leads to oesophageal rupture
What tests should you do for haematemesis
U&E - urea raised in upper GI bleed
Lactate - tells you how perfused the patient is
LFT
PTR - prothrombin time ratio
What are some potential causes of haematemesis due to alcoholism
Gastritis, Mallory wises tear, peptic ulcer, oesophageal varices
