neonatal jaundice Flashcards
what is jaundice
yellow discolouration of the skin or sclera
where does jaundice start in babies?
face first (cephalo-caudal progression)
which type of bilirubin can pass through the blood brain barrier?
free in plasma
which bilirubin is water insoluble?
unconjugated
where is conjugated bilirubin excreted to?
the gut
how does liver metabolism and bilirubin interact?
Liver metabolism relies on bilirubin uptake via ligandin and then conjugation by uridine diphosphoglucuronyltransferase (UDPGT)
why are newborns inefficient at managing bilirubin?
because ligandin and UDPGT are low
why is jaundice worrying?
Bilirubin crosses the BBB and causes encephalopthay which can lead to Kernicterus
Small risk of Cerebral Palsy with high levels of Bilirubin
why does physiological jaundice occur?
increased production
decreased uptake and binding by liver cells
decreased conjugation
decreased excretion
increased enterohepatic circulation of bilirubin
when does pathological jaundice occur?
<24hrs of age
what can cause pathological jaundice?
usually due to haemolysis with excessive production of bilirubin
babies can be born with jaundice in
-severe haemolysis
-hepatitis
what are the investigations for pathological jaundice?
total bilirubin concentration (SBR)
maternal blood group and antibody titres (if Rh negative)
FBC
CRP
what are the causes of too long jaundice (pathological)
Breast milk jaundice (diagnosis of exclusion, cessation of breast feeding is not advised)
Poor milk intake
Haemolysis
Infection (especially urinary tract infection)
Hypothyroidism
is conjugated hyperbilirubinaemia normal?
no
ALWAYS ABNORMAL
what causes persistant conjugated hyperbilirubinemia?
hepatitis
biliary atresia
