FFinalistSouthampton · 2027
Child health
AKT · Child health/Neonatal & surgical

Neonatal jaundice

Unconjugated (usually) — bilirubin handling

Overview

Jaundice in ~60% of term and ~80% of preterm babies. Timing is everything: 14 days (prolonged) needs a split bilirubin to exclude biliary atresia.

Recognise

  • <24h: pathological — haemolysis (rhesus/ABO, G6PD, spherocytosis) or sepsis
  • Day 2–14: physiological or breast-milk jaundice (unconjugated)
  • >14 days (>21 if preterm) = prolonged → split bilirubin
  • Conjugated (>25 µmol/L or >20%): pale stools, dark urine → biliary atresia until proven otherwise

Red flags

  • Jaundice <24h of age; conjugated (pale stool/dark urine); bilirubin above treatment threshold; encephalopathy (kernicterus)

Differentials & how to tell them apart

Physiological jaundiceunconjugated, day 2–14, well baby, normal stool/urine
Biliary atresiaCONJUGATED jaundice, pale stools, dark urine — surgical emergency (Kasai <60 days)
Haemolytic disease<24h onset, positive DAT, anaemia
Breast-milk jaundiceprolonged but unconjugated, thriving breastfed baby, self-limiting

Investigations

Total AND conjugated (split) bilirubin plotted on age-specific (hours) treatment threshold graphs. <24h or prolonged: FBC, blood film, blood group + DAT (Coombs), G6PD, TFTs, septic screen, conjugated fraction; LFTs/USS if conjugated.

Management

Phototherapy guided by age-specific bilirubin threshold charts

  1. 1Plot bilirubin against the hour-specific threshold chart. Phototherapy if above the line.Gate: Jaundice <24h of age is ALWAYS pathological → urgent investigation, do not wait
  2. 2Above the exchange line, or bilirubin encephalopathy: exchange transfusion ± IVIG.
  3. 3Prolonged (>14d) with CONJUGATED fraction → urgent investigation for biliary atresia.
Phototherapy — converts bilirubin to water-soluble isomers; threshold-guided
Exchange transfusion — for very high/rapidly rising bilirubin or encephalopathy
IVIG — in isoimmune haemolytic disease

Key points

Kernicterus = unconjugated bilirubin crossing the blood–brain barrier → athetoid cerebral palsy, deafness. Prevent by threshold-guided treatment.

Monitor & prognosis

Serial bilirubin; neuro exam; ensure feeding/hydration.

Excellent if treated to threshold; kernicterus is preventable and devastating.

Source: NICE CG98 (neonatal jaundice)