Glucose-6-phosphate dehydrogenase deficiency: a potential source of severe neonatal hyperbilirubinaemia and kernicterus.

Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is a commonly occurring enzyme defect that can lead to severe neonatal hyperbilirubinaemia and kernicterus. Both increased haemolysis, sometimes due to an identifiable chemical trigger or to infection, and diminished bilirubin conjugation, the result of an interaction between G-6-PD deficiency and Gilbert's syndrome, contribute to the pathogenesis of the jaundice. Phototherapy is the mainstay of treatment, with exchange transfusion held in reserve for those neonates who do not respond to phototherapy. Pharmacological agents such as Sn-mesoporphyrins, which prevent bilirubin production by inhibiting the enzyme heme oxygenase, can limit hyperbilirubinaemia and possibly prevent the need for exchange transfusion. Predischarge serum total bilirubin screening is useful in predicting which neonates are at high risk for developing hyperbilirubinaemia. Migration patterns make G-6-PD deficiency a condition which may nowadays be encountered in virtually any corner of the globe and a high degree of physician awareness is essential.