You ask the paediatrician about the baby’s history and discover:
- she has never had a blood tranfusion
- mum does not have an allogenic antibody
- there is no known family history of haemolysis
- there are signs of jaundice
Further tests show
Reticulocyte count 436 (reference range for age 50-100)
Direct antibody test is negative
What is the most likely differential diagnosis and what further tests could be done to make the diagnosis?