Paediatrics for NEET-PG
Neonatal Jaundice for NEET-PG
Neonatal jaundice is yellow discolouration of the skin and sclera from raised bilirubin, seen in most newborns because of physiological immaturity of bilirubin handling. For NEET-PG, the crucial skill is separating benign physiological jaundice from pathological jaundice that threatens the brain. Physiological jaundice appears after 24 hours, peaks around day 3 to 5 in term babies, stays below defined thresholds, and resolves within about two weeks. Pathological jaundice is flagged by onset within the first 24 hours, a rapid rise, high total bilirubin, conjugated hyperbilirubinaemia, or persistence beyond two weeks. Jaundice within 24 hours is haemolytic until proven otherwise, most often from Rh or ABO incompatibility or G6PD deficiency. Unconjugated bilirubin is fat soluble and can cross the blood-brain barrier to cause kernicterus, a devastating deposition in the basal ganglia producing choreoathetoid cerebral palsy, hearing loss, and upward gaze palsy. Breastfeeding jaundice occurs early from inadequate intake, while breast milk jaundice appears later and is prolonged but benign. Conjugated hyperbilirubinaemia always needs evaluation for biliary atresia and neonatal hepatitis. Management uses phototherapy, which isomerises bilirubin into water-soluble forms, and exchange transfusion for dangerously high levels. Interpreting bilirubin charts, recognising kernicterus, and knowing the phototherapy mechanism are consistent exam anchors.
MedNext Academy | 3 min read
Neonatal Jaundice for NEET-PG
Neonatal jaundice is yellow discolouration of the skin and sclera from raised bilirubin, seen in most newborns because of physiological immaturity of bilirubin handling. For NEET-PG, the crucial skill is separating benign physiological jaundice from pathological jaundice that threatens the brain. Physiological jaundice appears after 24 hours, peaks around day 3 to 5 in term babies, stays below defined thresholds, and resolves within about two weeks. Pathological jaundice is flagged by onset within the first 24 hours, a rapid rise, high total bilirubin, conjugated hyperbilirubinaemia, or persistence beyond two weeks. Jaundice within 24 hours is haemolytic until proven otherwise, most often from Rh or ABO incompatibility or G6PD deficiency. Unconjugated bilirubin is fat soluble and can cross the blood-brain barrier to cause kernicterus, a devastating deposition in the basal ganglia producing choreoathetoid cerebral palsy, hearing loss, and upward gaze palsy. Breastfeeding jaundice occurs early from inadequate intake, while breast milk jaundice appears later and is prolonged but benign. Conjugated hyperbilirubinaemia always needs evaluation for biliary atresia and neonatal hepatitis. Management uses phototherapy, which isomerises bilirubin into water-soluble forms, and exchange transfusion for dangerously high levels. Interpreting bilirubin charts, recognising kernicterus, and knowing the phototherapy mechanism are consistent exam anchors.
Neonatal jaundice is yellow discolouration of the skin and sclera from raised bilirubin, seen in most newborns because of physiological immaturity of bilirubin handling. For NEET-PG, the crucial skill is separating benign physiological jaundice from pathological jaundice that threatens the brain. Physiological jaundice appears after 24 hours, peaks around day 3 to 5 in term babies, stays below defined thresholds, and resolves within about two weeks. Pathological jaundice is flagged by onset within the first 24 hours, a rapid rise, high total bilirubin, conjugated hyperbilirubinaemia, or persistence beyond two weeks. Jaundice within 24 hours is haemolytic until proven otherwise, most often from Rh or ABO incompatibility or G6PD deficiency. Unconjugated bilirubin is fat soluble and can cross the blood-brain barrier to cause kernicterus, a devastating deposition in the basal ganglia producing choreoathetoid cerebral palsy, hearing loss, and upward gaze palsy. Breastfeeding jaundice occurs early from inadequate intake, while breast milk jaundice appears later and is prolonged but benign. Conjugated hyperbilirubinaemia always needs evaluation for biliary atresia and neonatal hepatitis. Management uses phototherapy, which isomerises bilirubin into water-soluble forms, and exchange transfusion for dangerously high levels. Interpreting bilirubin charts, recognising kernicterus, and knowing the phototherapy mechanism are consistent exam anchors.
Key points
- **Physiological jaundice:** Appears after 24 hours, peaks day 3 to 5 in term babies, stays within thresholds, and resolves by about two weeks.
- **Pathological flags:** Onset within 24 hours, rapid rise, high total bilirubin, conjugated fraction raised, or persistence beyond two weeks needs workup.
- **Day-one jaundice:** Jaundice within the first 24 hours is haemolytic until proven otherwise, commonly Rh, ABO incompatibility, or G6PD deficiency.
- **Unconjugated risk:** Unconjugated bilirubin is fat soluble, crosses the blood-brain barrier, and causes kernicterus by depositing in basal ganglia.
- **Kernicterus features:** Choreoathetoid cerebral palsy, sensorineural hearing loss, upward gaze palsy, and dental enamel dysplasia are classic sequelae.
- **Breastfeeding jaundice:** Early jaundice from inadequate feeding and dehydration in the first week. Managed by improving feeding frequency.
- **Breast milk jaundice:** Later onset, prolonged, benign, unconjugated jaundice thought to involve substances in milk. It resolves without stopping breastfeeding.
- **Conjugated jaundice:** Always pathological. Evaluate urgently for biliary atresia and neonatal hepatitis, since biliary atresia needs early Kasai surgery.
- **Phototherapy mechanism:** Blue light converts unconjugated bilirubin into water-soluble isomers and lumirubin that are excreted without conjugation.
- **Exchange transfusion:** Used for dangerously high bilirubin or signs of encephalopathy to physically remove bilirubin and antibody-coated red cells.
- **Coombs test:** A positive direct Coombs test confirms immune haemolysis such as Rh or ABO incompatibility as the cause of jaundice.
Frequently Asked Questions
How is physiological jaundice distinguished from pathological?
Physiological jaundice appears after 24 hours and stays within thresholds, while pathological jaundice appears within 24 hours, rises rapidly, or is conjugated or prolonged.
Why is unconjugated bilirubin dangerous?
Unconjugated bilirubin is fat soluble and can cross the blood-brain barrier, depositing in the basal ganglia to cause kernicterus.
How does phototherapy work?
Phototherapy uses blue light to convert unconjugated bilirubin into water-soluble isomers and lumirubin, which the body excretes without hepatic conjugation.
What causes jaundice on the first day of life?
Jaundice within 24 hours is haemolytic until proven otherwise, most often due to Rh or ABO incompatibility or G6PD deficiency.
Why is conjugated hyperbilirubinaemia always investigated?
Conjugated jaundice is never physiological and may indicate biliary atresia, which needs early Kasai surgery, or neonatal hepatitis.
Continue reading
NEET-PGComplete NEET-PG guide
Review the exam pattern, preparation and resources.
Practise Paediatrics for NEET-PG
Explore clinician-written learning resources, structured revision and practice across the MedNext platform.
See plans