Causes of unconjugated hyperbilirubinaemia
1. Breast milk jaundice
2. Inadequate feeding
3. Haemolysis (G6PD, spherocytosis, ABO/Rh incompatibility etc)
4. Conjugations defects (Gilbert, CN syndrome)
5. Hypothyroidism, galactosaemia
Breastmilk jaundice is a benign form of unconjugated hyperbilirubinaemia associated with breastfeeding, possibly due to enhanced bilirubin uptake. At 4 weeks 10% of breast-fed infants are jaundiced, but only 1 in 1,000 of formula-fed infants. It may persist as long as 12 weeks with spontaneous resolution, but more often before 4 weeks. Breastfeeding interruption is not usually indicated as a diagnostic or therapeutic intervention.
Ask the following questions to distinguished from other causes, including breastfeeding failure, sepsis, and cholestatic jaundice.
1. Breastfeeding well?
2. Gaining weight?
3. Adequate urine and stool output?
4. Stools yellow?
5. Well or ill on examination?
1. Split bilirubin (TSB and direct) (to measure the serum bilirubin level and to distinguish un/conjugated jaundice)
2. CBC, reticulocyte count, G6PD, Coombs (evidence of haemolysis and underlying cause)
3. TFT (to exclude hypothyroidism)
If infant with jaundice is afebrile and well, testing for UTI is not indicated.
TSB less than 200 micromol/l
Consistent with breast milk jaundice
No further workup indicated
Anticipate resolution by 12 weeks
TSB = 200 - 350 micromol/l
Evidence of haemolysis?
Consider repeating TSB
TSB more than 350 micromol/l
Admit to hospital for phototherapy
Workup for underlying pathology
Consider BF interruption and trial of formula
If conjugated (direct) bilirubin >35 mmol/l or >20% of total bilirubin, admit for investigations for cholestatic jaundice.