liver disease Flashcards
what are some liver issues
- viral liver disease = hepatitis
- jaundice
cirrhosis - liver failure
where does the liver sit
- under the ribs adjacent to the lungs
- it is separated from the lungs by the diaphragm
how can you feel your liver
- if you take a deep breath in
- if it is not healthy, and is inflamed the you can feel your liver without taking a deep breath
how many lobes does the liver have
3
- each lobe can function separately so you can transplant just one lobe to someone
how does the liver cope with its function
- it can regenerate and expand
what is the gall bladder
- collects bile from the liver
- sits up against the diaphragm
- the duct that takes bile from the gall bladder is the common bile duct which goes down to the pancreas
what is jaundice
- an accumulation of bilirubin in the skin
what is bilirubin
it the normal metabolic product of haem = breakdown haem and it is absorbed and excreted
- bilirubin in the blood should be low and undetectable
what can jaundice cause
- if it is high then it will spread from the blood stream and into the skin to cause pigmentation
- can cause an itch = bilirubin in the skin can upset the nerve endings and cause an itch
what is the other term for jaundice
- icteric
what colour is bilirubin
- yellowy/orange which then makes the skin that colour
what are the scleral effects of jaundice
- easier to see jaundice around the eyes
- it is the first place you will begin to see it
what is the pathway for bilirubin
- haem –> biliverdin –> bilirubin
- get bilirubin from haem metabolism = most haem is recycled but small amount is lost in each cycle
- liver takes bilirubin and conjugates it to be removed from the body = not conjugated means it is not water soluble so can’t be removed from the body in the urine
what does the colour of stool depend on
- depends on the conjugation of bilirubin
how much bilirubin is there in jaundice
- excess in circulation
what are the 3 ways to describe jaundice
- pre-hepatic
- hepatic
- post-hepatic
what is pre-hepatic
- increased haem load
- autoimmune, spleen, abnormal RBC’s
- increased bilirubin production beyond the liver’s capacity to conjugate it
what is hepatic
- liver cell failure
- cirrhosis, hepatitis
what is post-hepatic
- biliary, gall bladder and pancreatic disease
what is the normal bilirubin metabolism
- blood has a small amount of unconjugated bilirubin
- some passes through the cells through the endoplasmic reticulum and others remain in the blood
- the bilirubin that goes through the cells then enters the canaliculus in the liver and becomes conjugated and it then excreted out of the body
- most of the bilirubin goes through the cells - only a very small amount is left in the blood
what causes pre-hepatic jaundice
- jaundice due to factors before the liver metabolism
- usually excessive quantities of red blood cells breakdown products
what happens in pre-heptic jaundice
- too much bilirubin so stops the liver ability to conjugates so the amount of non-conjugated bilirubin in the blood is higher than it should be
- could be due to
= haemolytic anemia - bed blood cells broken down faster than they should be (60 days instead of 120)
= post tranfusion - from a bad match so there is more red blood cells for liver to deal with
= neonatal - at birth when maternal red blood cells mix with baby blood during delivery so overload baby’s liver function
how much bilirubin is there in pre hepatic
- there is more than normal amounts of both conjugated and non-conjugated bilirubin
what is a disease from pre-hepatic
Gilbert’s disease
what is Gilbert’s disease
- decreased bilirubin uptake by liver cells
what causes hepatic jaundice
- due to liver failure = cirrhosis of drug induced liver dysfunction
- number of hepatocytes are reduced so reduced ability of the liver to process the bilirubin, so the amount of unconjugated bilirubin accumulates
what happens in hepatic jaundice
- prevents metabolism of red blood cells breakdown products
- imparted bilirubin conjugation
- too few cells to do the job = so bilirubin passes through the liver but then goes straight back out into the blood instead of passing right through, returns to the blood unchanged
what happens in secretion failure of hepatic jaundice
- defective secretion of conjugation bilirubin from liver cells
- liver cell membrane is impermeable so bilirubin can’t get through to be excreted
- means that non-conjugated bilirubin that passed through the cells and became conjugated returns to the blood conjugated as it can get through to be excreted
- means there is a mixture of both conjugated and unconjugated bilirubin in the blood
what happens in post-hepatic jaundice
- bile tree is blocked so bile can’t escape into the intestine so backs up and goes into the blood
- there is an obstruction to bile outflow
- intra-hepatic biliary system = primary biliary sclerosis, the bile system doesn’t work
- extra-hepatic biliary system = gall bladder or common bile duct
- there is an obstruction somewhere in the biliary network
what bilirubin is in the blood due to post-hepatic jaundice
- both unconjugated and conjugated
how can the gall bladder be blocked in post-hepatic jaundice
- gall stones
- these are the most common forms of bile duct blockage
- if you have a bile duct blockage you want it to be gall stones as these are easiest treated
how can the common bile duct be blocked in post hepatic jaundice
- pancreatic carcinoma = tumour of the head of the pancreas, as it extends it will squash the bile duct and block it
- cholangiocarcinoma = tumour of the bile duct itself
- poor outcome for patients with either of these = 1-2 years at most
what are the clinical features of jaundice
- conjugated bilirubin is excreted in the urine and faeces = colour changes with cause of jaundice
what is the colour of stool in post hepatic jaundice
- pale stool and dark urine
- conjugated bilirubin causes jaundice
- if block the bowel tree then conjugated bilirubin can’t get to the small intestine so stool will be pale
- obstructive jaundice = yellow eyes, dark urine and pale stool
what makes stool dark
- if get bilirubin through, excess bilirubin
what colour of stool is in pre hepatic
- everything is normal as normal function of bilirubin still happening
- will get dark urine and stool