Preterm infants managed for hyperbilirubinemia according to Morioka's criteria

This study aimed to determine the clinical characteristics in preterm infants managed according to Morioka's criteria for jaundice treatment and predictors of prolonged hyperbilirubinemia.

A total of 117 preterm infants who were born at less than 30 weeks of gestation, admitted to the neonatal intensive care unit between 2019 and 2023, managed according to Morioka's jaundice treatment criteria, and discharged alive were analyzed. Phototherapy (either standard or intensive) was administered in accordance with the criteria. Prolonged hyperbilirubinemia was defined as the continued need for phototherapy beyond 14 days of age. Infants were classified into two groups based on the presence or absence of prolonged hyperbilirubinemia. Associations with various clinical factors, including heterozygous or homozygous variants of the UDP glucuronosyltransferase family 1A1 (UGT1A1) gene (UGT1A1*6 and UGT1A1*28), were analyzed. Prognostic evaluation included the assessment for bilirubin encephalopathy.

Of the 117 infants, 115 (98%) received phototherapy. The median duration of phototherapy was 4 days. Prolonged hyperbilirubinemia developed in 20 infants (17%); its occurrence was significantly associated with the use of intensive phototherapy before 14 days of age and the presence of the UGT1A1*6 variant (p = 0.004 and 0.001, respectively). None of the infants developed bilirubin encephalopathy.

The median duration of phototherapy in preterm infants born at less than 30 weeks' gestation managed according to Morioka's criteria was 4 days. Approximately 20% of the preterm infants develop prolonged hyperbilirubinemia. An increased risk is associated with the need for intensive phototherapy and the presence of the UGT1A1*6 variant.