Red flags: When to be concerned about jaundice

Any infant who has persistent jaundice after 2 weeks should have a split bilirubin test to distinguish between unconjugated and conjugated jaundice
Conjugated hyperbilirubinaemia indicates liver disease requiring referral to a liver specialist centre for urgent investigation.

Important features from history

Family history of jaundice, neonatal deaths or miscarriages
Low or normal birth weight, failure to thrive or weight loss
Poor feeding and irritability
Hypoglycaemic episodes
Vitamin K deficiency with bleeding

Examination

Babies with significant liver disease may have a normal birth weight and normal physical examination
Dysmorphic features, arthrogryposis, cutaneous haemangioma
Cardiac murmur
Enlarged spleen: always an abnormal sign
Ascites

Investigations (Algorithm 17.1 and Algorithm 17.2)

The differential diagnosis and investigations for causes of unconjugated jaundice are shown in Table 17.1 and causes of conjugated jaundice are shown in Table 17.2.

Algorithm 17.1 Investigating a 2-week-old infant with jaundice

Algorithm 17.2 Investigating conjugated hyperbilirubinaemia at 2 weeks of age

Table 17.1 Differential diagnosis of unconjugated hyperbilirubinaemia and recommended investigations

Differential diagnosis	Investigation	Results
Physiological jaundice	Split bilirubin	Mildly raised unconjugated bilirubin
Breast milk jaundice	Split bilirubin	Mildly raised unconjugated bilirubin
Sepsis	Blood, urine, CSF culture, chest X-ray	Positive culture or changes on X-ray
Haemolysis	Full blood count LDH Reticulocyte count Haptoglobins	Anaemia with fragmented red cells Raised LDH High reticulocyte count Low haptoglobins
Hypothyroidism	TFTs	High TSH Low T4
Pyloric stenosis	Ultrasound scan	Thickening of the gastric pylorus muscle. Excessive gastric peristalsis
Gilbert’s syndrome	Split bilirubin	Mild unconjugated hyperbilirubinaemia
Crigler–Najjar I and II	Split bilirubin	Significantly raised unconjugated hyperbilirubinaemia requiring treatment (see Algorithm 17.1)