Paediatric jaundice Flashcards
When dealing with paediatric jaundice - you must appreciate the age of the baby as this can indicate what the cause of jaundice might be - and also how serious it is
What are causes of early infant jaundice - in a baby less than a day old?
Jaundice in baby < day is always pathological
Can be due to:
Haemolysis
Sepsis
When dealing with paediatric jaundice - you must appreciate the age of the baby as this can indicate what the cause of jaundice might be - and also how serious it is
What are the causes of intermediate infant jaundice - in a baby 1 day - 2 weeks old?
Can be physiological jaundice (ie not pathological)
Can be due to:
- Breast milk jaundice
- Haemolysis
- Sepsis
When dealing with paediatric jaundice - you must appreciate the age of the baby as this can indicate what the cause of jaundice might be - and also how serious it is
What are the main causes of prolonged infant jaundice - in a baby > 2 weeks old?
Extrahepatic obstruction
Neonatal hepatitis
Hypothyroidism
Breast milk jaundice
What is meant by physiological jaundice?
Jaundice that most babies get to some degree - due to a number of things:
- Short RBC lifespan (due to HbF)
- Relative polycythaemia
- Immature liver function (doesnt conjugate v well yet)
This leads to unconjugated jaundice - that is fairly normal but doesnt happen until after 1 day of life
Compare breatsfeeding & formula feeding in the context of jaundice
Breastfeeding typically causes more jaundice and prolongation of jaundice in babies
What are the clinical aspects of breastmilk jaundice?
Failry normal - nobody really knows what causes it
Unconjugated jaundice
Can persist up to 12 weeks
If jaundice is normal in babies and most often due to harmless physiological causes - then why do we assess babies with jaundice?
Kernicterus - a complication of neonatal jaundice (even physiological i think)
What is kernicterus?
Kernicterus = bilirubin-induced brain dysfunction
This happens due to high levels of unconjugated bilirubin crossing the blood brain barrier
Bilirubin is neurotoxic and deposits in the brain - especially in the basal ganglia
Why is it only unconjugated bilirubin that causes kernicterus?
Unconjugated bilirubin is water insoluble - and thus fat soluble
This means it can cross the blood-brain barrier
What are the clinical features of kernicterus?
What are the potential consequences of it?
Encephalopathy:
- poor feeding
- lethargy
- then seizures
Consequences:
- severe choreoathetoid cerebral palsy
- learning difficulties
- sensorineural deafness
What treatment options are available for treatment of unconjugated jaundice of a neonate?
What are the indications for each?
Photo-therapy
Visible light (450nm) causes photoisomerisation of unconjugated bilirubin into a water soluble isomer
This is used when rising unconjugated bilirubin levels are detected - to prevent them getting to a level where kernicterus is a risk
Exchange transfusion
This is the treatment for already very high levels of unconjugated bilirubin - ie just before or at the level causing kernicterus
What are the other causes of early/intermediate unconjugated jaundice in newborns?
Sepsis
Haemolysis:
- ABO or Rhesus incompatible
- Bruising / cephalhaematoma
- Red cell membrane defects - eg Spherocytosis
- Red cell enzyme defects - eg G6PD deficiency
Abnormal conjugation:
- Gilbert’s disease - common but mild
- Crigler-Najar syndrome - rare and severe
How would you investigate the following causes of unconjugated jaundice…
a) Sepsis?
Hameolysis caused by:
- b) ABO or Rhesus incompatibility?
- c) Bruising / cephalhaematoma?
- d) Red cell membrane defects - eg spherocytosis?
- e) “ enzyme defects - eg G6PD deficiency?
a) Sepsis - urine & blood cultures, TORCH screen
Haemolysis caused by:
b) ABO / Rhesus - blood group, Direct Coombs Test (DCT)
c) Bruising / cephalhaematoma - examination
d) Spherocytosis etc - blood film
e) G6PD deficiency etc - G6PD assay or similar
Define prolonged infant jaundice
Any jaundice of the infant lasting beyond 2 weeks of life
(or 3 weeks for preterm)
What are the main causes of prolonged infant jaundice?
What type of jaundice is seen in each
Anatomical (biliary jaundice) - conjugated
Neonatal hepatitis - conjugated
Hypothyroidism - unconjugated
Breast milk jaundice - unconjugated
What is biliary atresia?
What are its mean clinical features?
Congenital fibro-inflammatory disease of bile ducts leading to destruction of extra-hepatic bile ducts
Prolonged, conjugated infant jaundice
Really pale stools & dark urine
Progression to liver failure - if not treated
Mc cause of liver transplant in infants
What is the treatment for biliary atresia?
Kasai portoenterostomy
Must be done < 60 days
(if progressed to bad liver failure - then transplant i assume)
