Crigler-Najjar Syndrome in a Neonate With Prolonged Jaundice

Mridula Arabu Manjunath, Pradeep Gejjigenahalli Channabasappa Maralusiddappa, Sharanabasavesh Mangalgi, Krithika Manne Veerabhadraiah

Abstract

Crigler-Najjar syndrome is an autosomal recessive disorder characterized by the absence or decreased activity of uridine 5ʹ-diphosphate (UDP) glucuronosyltransferase.

We report a case of a 25-day-old female neonate diagnosed with Crigler-Najjar syndrome type 2. She is the second born of a nonconsanguineously married couple with no family history of jaundice. The neonate presented with prolonged jaundice, and her total serum bilirubin level was 29.75 mg/dL, with direct bilirubin of 2.05 mg/dL. Although the serum bilirubin level reduced with phototherapy, it increased again after phototherapy was stopped. All other causes of prolonged jaundice were ruled out.

In view of persistent hyperbilirubinemia, Crigler-Najjar syndrome was suspected, and genetic workup was done. Genetic workup confirmed Crigler-Najjar syndrome type 2 with heterozygous mutations in exon 1 and exon 3 of the UDP glucuronosyltransferase (UGT1A1) gene. The neonate was prescribed oral phenobarbitone treatment, and her serum bilirubin level reduced at follow-up after 2 weeks.

Crigler-Najjar syndrome type 1, Crigler-Najjar syndrome type 2, and Gilbert syndrome are caused due to mutations in the bilirubin UGT1A1 gene on chromosome 2q37. These syndromes should be considered as a possible cause of prolonged jaundice or persistent hyperbilirubinemia, and genetic workup should be ordered, though the incidence is rare.