Jaundice in the newborn
Exam Tips
- In OSCEs, explicitly state that visual inspection cannot quantify bilirubin severity; confirm with serum bilirubin and age-specific treatment thresholds.
- Jaundice in first 24 hours is pathological until proven otherwise and needs urgent paediatric/neonatal assessment.
- Ask directly about stool and urine colour: pale stools + dark urine strongly suggest conjugated jaundice/cholestasis.
- Remember prevalence figures: around 60% of term and 80% of preterm babies are jaundiced in week 1.
- Use red-flag neuro signs (poor suck, high-pitched cry, abnormal tone/opisthotonus, seizures) to identify possible acute bilirubin encephalopathy quickly.
- For viva illustration of cephalocaudal spread and stool-colour warning signs, refer to standard neonatal examination diagrams and stool-colour charts used in UK newborn care materials.
Definition
Neonatal jaundice is yellow discoloration of a newborn’s skin and sclera caused by hyperbilirubinaemia from bilirubin accumulation. It is very common in the first week of life and is usually physiological, but early-onset (<24 hours), rapidly rising, prolonged, or conjugated jaundice can indicate serious disease and risk bilirubin neurotoxicity.
Pathophysiology
Neonates produce more bilirubin than adults because they have a higher red cell mass and shorter red cell lifespan. Haem breakdown generates unconjugated bilirubin, which is albumin-bound in plasma; immature hepatic uptake/conjugation (UGT activity) and increased enterohepatic circulation make early neonatal unconjugated hyperbilirubinaemia common. If unconjugated bilirubin rises markedly, unbound bilirubin can cross the blood-brain barrier (especially with prematurity, sepsis, hypoxia, acidosis, or low albumin) and cause acute bilirubin encephalopathy/kernicterus. Conjugated hyperbilirubinaemia suggests hepatobiliary pathology (for example biliary atresia, neonatal hepatitis, metabolic disease) rather than physiological jaundice.
Risk Factors
- Prematurity (lower gestational age)
- Low birth weight
- Jaundice appearing in first 24 hours
- Previous sibling/parental history of neonatal jaundice needing treatment
- Exclusive breastfeeding with suboptimal intake
- Dehydration or excessive postnatal weight loss
- Bruising/cephalhaematoma or birth trauma
- Maternal age >25 years
- East Asian or Mediterranean ethnicity
- Infant of diabetic mother (especially macrosomic infant)
- Family history of haemolytic disorders including G6PD deficiency
- Down syndrome
Clinical Features
Symptoms
- Parental concern about yellow skin or yellow eyes
- Poor feeding or reduced effective milk transfer
- Reduced wet/dirty nappies suggesting poor intake
- Dark urine and/or pale, chalky stools (red flag for cholestasis)
- Lethargy, irritability, fever, vomiting, or apnoeic episodes in unwell infant
Signs
- Cephalocaudal progression of jaundice (head then trunk/limbs with increasing severity)
- Visible jaundice in sclerae, gums, and blanched skin (harder to detect in darker skin)
- Fever or other signs of sepsis
- Dehydration and significant weight loss
- Bruising/cephalhaematoma
- Neurological signs of acute bilirubin encephalopathy: poor suck, altered tone, opisthotonus, high-pitched cry, seizures, coma
Investigations
Management
Lifestyle Modifications
- Urgent same-day assessment for jaundice in first 24 hours, rapidly worsening jaundice, or any unwell infant
- Support effective feeding (breastfeeding/formula support), monitor weight and hydration, and track nappies
- Provide parents with safety-net advice: seek urgent care for poor feeding, lethargy, fever, arching/high-pitched cry, dark urine, or pale stools
- Do not use sunlight exposure as treatment because of unreliable efficacy and safety concerns
- Document jaundice assessment at each neonatal contact, especially first 72 hours
Pharmacological Treatment
Immunoglobulin for immune haemolysis
- Human normal immunoglobulin (IVIG) 500 mg/kg IV over 4 hours; may repeat once after 12 hours in specialist neonatal care
Used when isoimmune haemolytic disease is driving severe/rising unconjugated bilirubin despite intensive phototherapy. Monitor for infusion reactions, haemolysis, thrombosis, renal impairment, and fluid overload; use neonatal specialist protocol.
Surgical / Interventional
- Exchange transfusion for severe hyperbilirubinaemia at/above treatment thresholds or with signs of acute bilirubin encephalopathy despite intensive phototherapy
- Cause-specific procedures when indicated, for example Kasai portoenterostomy for biliary atresia
Complications
- Acute bilirubin encephalopathy
- Kernicterus (clinical-pathological syndrome of bilirubin neurotoxicity)
- Chronic bilirubin encephalopathy with choreoathetoid cerebral palsy
- Sensorineural hearing impairment
- Developmental delay, learning and visual problems
- Seizures and permanent neurological disability
Prognosis
Most neonatal jaundice is physiological and resolves spontaneously (typically by about 2 weeks in term infants; longer in preterm infants). Prolonged unconjugated jaundice in a well baby is often benign and self-limiting, but outcomes depend on rapid recognition of severe hyperbilirubinaemia and underlying causes; timely phototherapy/escalation prevents most bilirubin toxicity.
Sources & References
✅NICE Guidelines(1)
- Jaundice in the newborn[overview]
📖Textbook References(2)
- [Oxford Medical Handbooks] Ian Wilkinson, Tim Raine, Kate Wiles, Anna Goodhart, Catriona Ha - Oxford Handbook of Clinical Medicine (2017, Oxford University Press) - libgen.li.pdf(pp. 287)[context]
- [Oxford Medical Handbooks] Ian Wilkinson, Tim Raine, Kate Wiles, Anna Goodhart, Catriona Ha - Oxford Handbook of Clinical Medicine (2017, Oxford University Press) - libgen.li.pdf(pp. 286, 287)[context]