Etiology analysis for term newborns with severe hyperbilirubinemia in eastern Guangdong of China

Molecular biology of glucose-6-phosphate dehydrogenase and UDP-glucuronosyltransferase 1A1 in the development of neonatal unconjugated hyperbilirubinemia

Glucose-6-phosphate dehydrogenase (G6PD) deficiency and variants of the UDP-glucuronosyltransferase 1A1 (UGT1A1) gene are the most common genetic causes of neonatal unconjugated hyperbilirubinemia (NUH). In this review, we searched PubMed for articles on the genetic causes of NUH published before December 31, 2022, and analyzed the data. On the basis of the results, we reached eight conclusions: (1) 37 mutations of the G6PD gene are associated with NUH; (2) the clinical manifestation of G6PD deficiency depends not only on ethnicity but also on the molecular mechanisms underlying the deficiency (and thus its severity); (3) of mutations in the UGT1A1 gene, homozygous c.-53A(TA)6TAA > A(TA)7TAA is the main cause of NUH in Caucasians and Africans, whereas homozygous c.211G > A is the main genetic cause of NUH in East Asians; (4) in Indonesian neonates, homozygous c.-3279T > G is the most common cause of NUH development, and neither c.-53 A(TA)6TAA > A(TA)7TAA nor c.211G > A causes it; (5) in breast-fed East Asian neonates, the TA7 repeat variant of the UGT1A1 gene protects against the development of NUH; (6) G6PD deficiency combined with homozygous c.211G > A variation of the UGT1A1 gene increases the risk of severe NUH; (7) in Pakistani and Caucasian patients with Crigler-Najjar syndrome type 2 (CN-2), point mutations of the UGT1A1 gene are widely distributed and frequently occur with variation at nucleotide -53, whereas in Asian patients with CN-2, compound homozygous variations in the coding region are frequently observed; and (8) records of G6PD deficiency and UGT1A1 variation status for a neonate offer useful pharmacogenomic information that can aid long-term care. These results indicate that timely diagnosis of NUH through molecular tests is crucial and that early initiation of treatment for the neonates and educational programs for their parents improves outcomes.

The Diagnostic Potential of the L Score for ABO Hemolytic Disease of the Newborn: Insights from a Cross-Sectional Study

Purpose

This study aimed to evaluate the diagnostic efficacy of the L score, a novel scoring system, in distinguishing between ABO hemolytic disease of the newborn (ABO-HDN) and non-hemolytic disease of newborn hyperbilirubinemia (NHDNH).

Methods

A cross-sectional prospective study was conducted to assess the effectiveness of the L score in distinguishing between ABO-HDN (n = 118) and NHDNH (n = 213). Blood routine examination results were collected, and relevant statistical analyses were performed to identify clinically significant parameters. Binary logistic regression analysis was employed to assess the relationship between the L score and the development of these conditions, considering relevant variables.

Results

Our study identified the red blood cell count, mean corpuscular volume, red blood cell distribution width-coefficient of variation, and red blood cell distribution width-standard deviation as independent risk factors for distinguishing ABO-HDN from other high bilirubinemia conditions (P < 0.001). The L score demonstrated superior predictive performance for ABO-HDN, exhibiting an area under the curve (AUC) of 0.746, with an optimal cutoff value of - 3.0816. The RBC-L score exhibited superior predictive performance (z: 5.596, P < 0.0001) compared to the single-factor RBC indicator, indicating its efficacy in accurately identifying the desired outcome.

Conclusion

The L score represents a valuable tool for predicting neonatal hyperbilirubinemia and hemolytic disease, facilitating differentiation, and guiding early intervention for improved outcomes. Further research is warranted to validate and expand the applicability of the L score in clinical practice.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12288-023-01723-5.

Prevalence and association of early onset severe hyperbilirubinemia in newborn in the East China region: Retrospective medical record analyses

Research on the prevalence and association of hyperbilirubinemia is controversial because of different cultures, demographics, and clinical conditions. The etiology of hyperbilirubinemia is affected by the environment and other factors in the newborn. The World Health Organization recommended a 1-day hospital stay after uncomplicated delivery, jaundice assessment before discharge, and screening on 3rd and 7th days after birth for hyperbilirubinemia. However, the implementation of these recommendations is difficult in China. The objective of this study was to evaluate the prevalence and association of early onset severe hyperbilirubinemia in newborns in East China. Retrospective medical record analyses for 250 cesarean sections or vaginal deliveries, ≥2 kg body weight, and negative for Hepatitis B surface antigen by birth newborns were performed. A biochemical analyzer, quantitative assay, and quantitative polymerase chain reaction were used to evaluate total serum bilirubin, glucose-6-phosphate dehydrogenase (G6PD) deficiency, and gene variant phenotyping, respectively. A total in 33 (13%) newborns were reported with early onset severe hyperbilirubinemia (according to the American Academy of Pediatrics, total serum bilirubin ≥ 342 μmol/L within 6 hours of birth). All newborns with severe hyperbilirubinemia were hospitalized and underwent phototherapy. The mothers of all newborns had a gestational age ≥ 35 weeks. Hospitalization included artificial feeding, and breastfeeding was rare (P < .0001). ABO incompatibility ("O" blood type for mother and either "A" or "AB" or "B" blood type for newborn, P = .0411), G6PD deficiency (G6PD/6-phosphogluconate dehydrogenase ≤ 1.0 in quantitative assay, P = .0422), Rh incompatibility (the mother's blood type was Rh negative and newborn blood type was Rh positive, P = .0416), fewer genotype rs4149056 frequencies (P = .0452), higher genotype rs2306283 frequencies (P = .0461), and higher genotype rs1805173 frequencies (P = .0471) were independent parameter for early onset severe hyperbilirubinemia of newborns. The prevalence of early onset severe hyperbilirubinemia in Chinese newborns is 13% in the East China region. Blood incompatibility, G6PD deficiency, fewer genotype rs4149056 frequencies, higher genotype rs2306283 frequencies, and higher genotype rs1805173 frequencies were independent predictors of early onset severe hyperbilirubinemia among newborns in the East China region (Level of Evidence: IV; Technical Efficacy: Stage 5).