Liver Flashcards
RECAP- functions of the liver?
Produces bile
Produces clotting factors
Role in absorption of fats, proteins and carbs
Glycogen storage
Albumin store
Excretion of toxic products
RECAP- which blood tests are included in LFTs?
Bilirubin- can be split into conjugated and unconjugated
ALT/AST
ALP
GGT
In which types of liver disease can ALT/AST be elevated?
Hepatocellular damage e.g. hepatitis
In which types of liver disease can ALP and GGT be elevated?
Biliary disease
LFTs are a better indication of how badly damaged the liver is.
Which tests are better tests to assess the function?
Coagulation- PT, APTT
Albumin
Bilirubin
Jaundice is the commonest presentation of liver disease in children. What is jaundice?
Yellow discolouration of the skin and tissues due to accumulation of bilirubin
Where is jaundice usually the most noticable?
Sclera of eyes
At what levels of bilirubin does jaundice then become more visibly noticed?
When total bilirubin >40-50umol/l
Looking for yellowing of the sclera is the best way to differentiate true jaundice and which condition?
Beta-carotene anaemia
->this is what Mr Page had when he ate too many carrots
Which cells are broken down to produce bilirubin?
RBCs
What is unconjugated bilirubin bound to?
Albumin
->this then gets transported to the liver
Which type of bilirubin is water soluble?
Conjugated bilirubin
->this is why unconjugated bilirubin is bound to albumin
Summarise the bilirubin metabolism pathway
RBCs -> unconjugated bilirubin (bound to albumin) -> liver to become conjugated
Then this goes into bile
So… if there is a pre-hepatic jaundice, where does the porblem occur?
Anywhere in the pathway before the liver, so involves unconjugated bilirubin
In intra-hepatic jaundice, where is the issue?
Liver
->both conjugated and unconjugated bilirubin as liver has issues with both
What issue is usually the cause of post-hepatic jaundice?
Obstructive cause preventing conjugated bilirubin getting out of the liver
Early onset jaundice occurs within 24hrs of birth and is ALWAYS pathological.
What are some of the causes?
Haemolysis, sepsis
Intermediate jaundice can occur between 24hrs-2wks after birth.
What are some of the causes?
Physiological
Breast milk
Haemolysis
Sepsis
Prolonged jaundice can occur in babies >2wks after birth.
What are some of the causes?
Extrahepatic obstruction
Neonatal hepatitis
Hypothyroidism
Breast milk
What type of jaundice is breast milk jaundice?
Unconjugated jaundice
Although neonatal jaundice is very common, and often doesn’t require treatment, there is one condition associated with jaundice which is severe.
What is it?
Kernicterus
Which type of bilirubin is there in kernicterus?
Unconjugated
Why is Kernicterus a potentially severe condition?
The unconjugated bilirubin is fat-soluble, and water insoluble, and can cross the blood-brain barrier.
It is neurotoxic and can deposit in the brain
What are the early signs of knericterus?
Encephalopathy
Poor feeding
Lethargy
Seizures
What are some of the late consequences of Kernicterus if it’s not treated?
Severe choreathetoid cerebral palsy
Learning difficulties
Sensorineural deafness
What treatment is done for unconjugated jaundice to avoid Kernicterus developing?
Phototherapy
How common and severe is Gilbert’s syndrome?
Common, mild severity
How common and severe is Crigler-Najjar syndrome?
V rare, severe
Which tests are done to confirm diagnosis of neonatal sepsis?
Urine, blood cultures, TORCH screen
Which tests are done to confirm diagnosis of Gilbert’s/Crigler-Najjar syndrome?
Genotype/phenotype testing
What is prolonged infant jaundice?
Jaundice persisting beyond 2wks of life
->beyond 3wks in preterm infants
What are some of the causes of prolonged infant jaundice?
Biliary obstruction
Neonatal hepatitis
Hypothyroidism
->could be breast-milk or physiological jaundice but more unlikely if more than 2wks
Causes of prolonged infant jaundice can be either conjugated or unconjugated.
What are the conjugated causes?
Biliary obstruction
Neonatal hepatitis
->makes sense as both occur within or after liver
Causes of prolonged infant jaundice can be either conjugated or unconjugated.
What are the unconjugated causes?
Hypothyroidism
Breast-milk jaundice
What does conjugated jaundice in infants always require?
Further investigation as always abnormal.
The most important test in prolonged jaundice is a ‘split’ bilirubin to determine the type
What are some of the things that can cause biliary obstruction and lead to prolonged jaundice?
Biliary atresia
Choledochal cyst
Alagille syndrome
Symptoms of biliary atresia and choledochal cysts?
Conjugated jaundice
Pale stools
->stools are pale because bilirubin is not getting excreted due to the blockage
Therefore, if you have a child with prolonged jaundice, what do you always want to check, as well as the type of bilirubin conjugation?
Stool colour
What happens in biliary atresia?
Congenital fibro-inflammatory disease of the bile ducts
If biliary atresia is not treated, what can it progress to?
Liver failure
->biliary atresia is the most common indication for liver transplant in children
Treatment for biliary atresia?
Kasai portoenterostomy
->success rate diminishes rapidly with age, best results if performed before 60 days
Which imaging modality is best for assessing the liver for biliary atresia/choledochal cysts?
Ultrasound
