Severe or recurrent neonatal jaundice warrants evaluation for underlying genetic disorders of bilirubin metabolism, particularly after excluding hemolysis and infection. We report the case of a term newborn with marked unconjugated hyperbilirubinemia requiring repeated hospitalizations and multiple courses of phototherapy. Molecular genetic testing revealed the coexistence of Crigler-Najjar syndrome and Gilbert syndrome, providing a genetic explanation for the severity and persistence of jaundice. This case highlights difficulties of its management and the importance of comprehensive genetic analysis in neonates with unexplained hyperbilirubinemia, especially in consanguineous families.

Keywords: Crigler-Najjar syndrome; Gilbert syndrome; Neonatal hyperbilirubinemia; Combined mutation; Case report