Neonatal jaundice: unconjugated hyperbilirubinaemia: SAQ

This infant is a late-preterm (36 weeks) exclusively breastfed male with early visible jaundice and a bilirubin of 280 micromol per litre at 30 hours. The unconjugated fraction predominates (conjugated only 12 micromol per litre). The key concerns are the low gestational age, early onset relative to age, suboptimal feeding with 9 per cent weight loss, and maternal blood group O placing the infant at risk for ABO incompatibility. [1]

Question 1 (10 marks)

Outline your assessment and investigation plan for this infant. [1]

Begin with a structured clinical assessment. Confirm the timing of jaundice onset, the gestational age, feeding pattern, stool and urine colour, and family history. Examine the infant for pallor suggesting haemolysis, cephalohaematoma or bruising, hepatosplenomegaly, and general wellness. Plot the total serum bilirubin of 280 micromol per litre on the hour-specific nomogram for a 36-week infant. At 30 hours this bilirubin falls in the high-risk zone, warranting investigation and likely phototherapy. [2]

The investigation plan focuses on excluding haemolysis and identifying risk factors. Perform a direct antiglobulin test (DAT) to detect antibody-coated red cells. Check maternal and infant blood groups and Rh status to assess for ABO or Rh incompatibility. Obtain a full blood count with reticulocyte count to identify anaemia and compensatory erythropoiesis, and a peripheral blood film for spherocytes (suggestive of ABO incompatibility or hereditary spherocytosis). Consider G6PD assay if the family heritage is at risk, noting that false-negative results can occur during acute haemolysis. The conjugated fraction of 12 micromol per litre is reassuring, excluding conjugated hyperbilirubinaemia and biliary atresia. [3]

Question 2 (10 marks)

Describe your management plan, including phototherapy decisions, feeding advice, and follow-up arrangements. [1]

The total serum bilirubin of 280 micromol per litre at 30 hours in a 36-week infant with risk factors places this infant above the phototherapy threshold for a higher-risk infant. Initiate intensive phototherapy immediately using high-intensity blue LED light at 430 to 490 nm with an irradiance of at least 30 microwatts per square centimetre per nanometre. Expose the maximal skin surface area (80 to 90 per cent), protect the eyes with opaque patches, and monitor temperature. [1]

Feeding management is critical. Continue breastfeeding and ensure adequate intake, as this infant has lost 9 per cent of birth weight, contributing to increased enterohepatic circulation of bilirubin. Supplement with expressed breast milk or formula if intake is inadequate. Do not stop breastfeeding. Monitor urine output, weight, and feeding effectiveness. [1]

Repeat the total serum bilirubin at 4 to 6 hours after starting phototherapy to confirm a response, defined as a decline of 17 to 34 micromol per litre within the first 4 to 6 hours. If the bilirubin continues to rise despite intensive phototherapy and the haemolytic workup confirms immune-mediated haemolysis with a positive DAT, administer intravenous immunoglobulin at 0.5 to 1 g per kg over 2 hours. Prepare for exchange transfusion if the bilirubin approaches the exchange threshold or if there are any signs of acute bilirubin encephalopathy. Once phototherapy is discontinued (bilirubin below the gestational-age-specific discontinuation threshold), arrange a rebound bilirubin check 12 to 24 hours later. Ensure a documented follow-up plan before discharge with a bilirubin check within 24 to 72 hours. [3]