Neonatal Jaundice

Question 1

Broad aetiologies of neonatal jaundices

Answer 1

Increased production

Decreased clearance

Question 2

Causes of increased production of bilirubin

Answer 2

Haemolytic disease of the newborn

ABO incompatibility

Haemorrhage

Intraventricular haemorrhage

Cephalo-haematoma

Polycythaemia

Sepsis and DIC

G6PD deficiency

Question 3

Causes of decreased clearance of bilirubin

Answer 3

Prematurity

Breast milk jaundice

Neonatal cholestasis

Extrahepatic biliary atresia

Endocrine disorders

Gilbert syndrome

Question 4

Physiological jaundice

Answer 4

High conc. of RBCs in foetus & neonate

Less developed liver function

Foetal RBCs break down more rapidly than normal RBCs, releasing lots of bilirubin

Normally excess bilirubin is excreted by placenta -> at birth foetus no longer has access to placenta

So normal bilirubin rise after birth (2-7 days)

Question 5

Jaundice in premature neonates

Answer 5

Exaggerated due to immature liver

Increased risk of complications e.g. kernicterus

Question 6

Breastmilk jaundice

Answer 6

Components of breastmilk inhibit ability of liver to process bilirubin

More likely to become dehydrated if not feeding adequately

Inadequate feeding may slow passage of stools, increasing absorption of bilirubin in intestines

Question 7

Haemolytic disease of the newborn

Answer 7

Incompatibility between rhesus antigens on surface of RBCs of mother and foetus

Usually causes problems in second/subsequent pregnancies

Question 8

Prolonged jaundice

Answer 8

More than 14 days in full term babies

More than 21 days in premature babies

Should prompt further investigation to look for underlying cause

Question 9

Investigations in neonatal jaundice

Answer 9

FBC and blood film for polycythaemia or anaemia

Conjugated bilirubin: elevated in HPB cause

Blood type testing for mother and baby for ABO or rhesus incompatibility

Direct Coombs test (direct antiglobulin test) for haemolysis

TFTs (hypothyroid)

Blood and urine cultures if infection suspected

G6PD levels for G6PD deficiency

Question 10

Management of neonatal jaundice

Answer 10

Monitor and plot bilirubin levels on threshold chart

If total bilirubin reaches threshold, commence treatment

Phototherapy usually adequate to correct neonatal jaundice

Exchange transfusion may be used if severe

Question 11

Complications of neonatal jaundice - kernicterus

Answer 11

Brain damage caused by excessive bilirubin levels

Bilirubin can cross BBB and cause permanent damage to CNS

Presents with less responsive, floppy baby with poor feeding

Causes cerebral palsy, learning disability and deafness