Biochemistry of Alcohol Flashcards
name 6 things that alcohol can affect in the body
liver pancreas heart muscle osmoregularity and coagulation glucose metabolism
which effect of alcohol can cause a coma?
disturbance of glucose metabolism
how can you determine if there is any damage to heart and muscle?
heart = measure troponin (specific to heart muscle) muscle = measure creatinine kinase
how do troponin levels rise/fall over time?
cant be detected for around 6 hours after onset of pain
peak around 24-48 hrs after and then return to normal over 5-14 days
what tests are used to determine whether the patient is a chronic drinker?
GGT (increased)
Mean cell volume of red cells (increased)
triglycerides (increased)
what does a raised GGT with normal LFTs suggest and why?
chronic drinker
ethanol induces enzymes including P450 and GGT
what test is used to determine if a coma is due to alcohol or other factors?
serum osmolality
what other factors can cause a comatose state other than alcohol?
anti-convulsive medication (i.e epilepsy) as they also induce same emzymes
what is serum osmolality?
calculated concentration of electrolytes/dissolved solutes in aqueous phase of serum (Na, Ca, K, urea etc)
how is serum osmolality calculated generally?
2X [Na] as Na is always by far the most prevalent electrolyte
(usually around 275-295)
what is the osmolal gap?
difference between calculated serum osmolality and measured serum osmolality (shouldn’t be much)
patient comes into A&E in a comatose state, all electrolytes are normal but a large osmolal gap is present, what does this mean?
something else is in blood contributing to osmolality which is not measured (i.e ethanol or methanol etc)
why are methanol and ethylene glycol so dangerous?
metabolised to very acidic metabolites
what tests are used to determine if alcohol is the cause of abdominal pain?
amylase (checks pancreas)
LFTs (checks gall bladder etc)
ascetic fluid analysis
what is ALT (alanine aminotransferase) a marker of?
liver damage
released from hepatocytes when damaged
where is alkaline phosphatase (ALP) found in the body?
bone liver small intestine kidneys placenta
what is ALP a marker of?
liver damage (found in bile canaliculi) excessive bone formation (in osteoblasts)
what does high GGT indicate?
liver damage/disease
pancreatitis
prostate/kidney disease
what is albumin and how can it be used in testing?
plasma protein formed by the liver
can indicate problem in liver function if low
why is albumin not a great marker of liver function?
it also falls during the inflammatory response as it is redistributed
half life of 3 weeks
what is a good indicator of current liver function and why?
prothrombin time as clotting factors are synthesised in the liver and it has a shorter half life of 3-4 days
what can cause prehepatic jaundice/unconjugated bilirubin overload?
haemolytic anaemia
what can cause conjugated bilirubin overload?
obstruction (e.g bile duct etc)
possible diagnosis of abdo pain in alcoholic?
acute pancreatitis
alcoholic hepatitis
peptic ulcer +/- perforation
ascites +/- fluid analysis
