# Neonatal Screening for Glucose-6-Phosphate Dehydrogenase (G6PD) Gene Variants and Their Association With Hyperbilirubinemia and Phototherapy Needs

## TL;DR

This study examines how common G6PD gene variants are in neonates and their link to jaundice and phototherapy needs.

## Contribution

The study identifies independent predictors of phototherapy in G6PD-deficient neonates, despite no variant-specific associations.

## Key findings

- G6PD deficiency was found in 10.6% of neonates, with the c.563C>T variant being most common.
- Female sex reduced phototherapy risk, while a positive Coombs test and two mutant gene copies increased it.
- Specific G6PD variants were not linked to hyperbilirubinemia severity.

## Abstract

Background and objectives: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is highly prevalent in the Middle East and is a recognized risk factor for neonatal hyperbilirubinemia. However, the clinical impact of specific G6PD gene variants on hyperbilirubinemia severity remains unclear. This study aimed to determine the prevalence of G6PD gene variants among neonates at Johns Hopkins Aramco Healthcare and to evaluate their association with hyperbilirubinemia severity and phototherapy requirements.

Methods: We conducted a retrospective cohort study of neonates diagnosed with G6PD deficiency between January 2021 and December 2023. Demographic, clinical, laboratory, and genetic data were collected from electronic medical records. G6PD variants were identified using newborn DNA screening. Associations with phototherapy requirement were assessed using chi-square and Mann-Whitney U tests. Univariate and multivariate logistic regression analyses were performed to identify independent predictors of phototherapy.

Results: Among 5,375 neonatal admissions, 572 (10.6%) neonates were diagnosed with G6PD deficiency, with a male predominance (66.6%). The c.563C>T (Mediterranean) variant was the most prevalent (93.5%). Phototherapy was required in 193 neonates (33.7%). In multivariate analysis, female sex was independently protective against phototherapy (adjusted odds ratio (AOR) = 0.239; p = 0.003), while a positive Coombs test (AOR = 8.668; p < 0.001) and the presence of two mutant G6PD gene copies (AOR = 3.890; p = 0.007) were significant independent predictors of phototherapy requirement. No significant association was observed between specific G6PD variants and the need for phototherapy.

Conclusion: G6PD deficiency was common in this cohort and was mainly associated with the c.563C>T mutation. A positive Coombs test and multiple gene copies were independent predictors of phototherapy, whereas specific G6PD variants were not associated with hyperbilirubinemia severity. These findings support the importance of early G6PD screening and vigilant monitoring to prevent severe neonatal hyperbilirubinemia.