Glucose-6-Phosphate Dehydrogenase Deficiency and Neonatal Hyperbilirubinemia: Insights on Pathophysiology, Diagnosis, and Gene Variants in Disease Heterogeneity

Integrated Phenotypic and Genotypic Approaches for Accurate Diagnosis of G6PD Deficiency: Implications for Drug Safety in Thailand

Glucose-6-phosphate dehydrogenase (G6PD) deficiency holds critical health concerns, particularly due to its association with drug-induced hemolysis triggered by medications such as antimalarials. This condition poses significant risks in malaria-endemic regions where the prevalence and genetic diversity of G6PD deficiency further complicate management. Providing accurate and reliable G6PD status is vital to ensuring safe treatment, reducing complications, and improving healthcare outcomes in these populations. This study evaluated the integration of phenotypic and genotypic diagnostic methods for identifying G6PD deficiency in 2953 participants in Thailand. Using the water-soluble tetrazolium salts enzymatic assay and multiplex high-resolution melting analysis, the study revealed an overall prevalence of 3.93%, with 7.19% in males and 1.83% in females. A total of 38 distinct G6PD genotypes were identified, and zygosity was determined, highlighting significant genetic diversity, including previously unreported mutations as identified by sequencing. Hemizygous males, homozygous females, and approximately 50% of heterozygous females with missense mutations exhibited deficient or intermediate phenotypes. However, 40% of females carrying G6PD missense mutations showed a normal phenotype in quantitative phenotypic testing. The findings highlight the need for accurate G6PD diagnosis to improve drug safety and efficacy, particularly for vulnerable individuals such as heterozygous females, who are at risk of hemolysis. The cost-effective, high-throughput methods demonstrated here are suitable for large-scale screening, making them especially valuable in resource-limited settings. To maximize their impact, integrating both phenotypic and genotypic approaches into national healthcare policies and malaria programs is essential. By ensuring equitable access to reliable G6PD testing, these findings support malaria elimination efforts and address broader healthcare challenges, ultimately reducing preventable morbidity and mortality associated with G6PD deficiency.

Improved genetic screening with zygosity detection through multiplex high-resolution melting curve analysis and biochemical characterisation for G6PD deficiency

Accurate diagnosis of glucose-6-phosphate dehydrogenase (G6PD) deficiency is crucial for relapse malaria treatment using 8-aminoquinolines (primaquine and tafenoquine), which can trigger haemolytic anaemia in G6PD-deficient individuals. This is particularly important in regions where the prevalence of G6PD deficiency exceeds 3%-5%, including Southeast Asia and Thailand. While quantitative phenotypic tests can identify women with intermediate activity who may be at risk, they cannot unambiguously identify heterozygous females who require appropriate counselling. This study aimed to develop a genetic test for G6PD deficiency using high-resolution melting curve analysis, which enables zygosity identification of 15 G6PD alleles. In 557 samples collected from four locations in Thailand, the prevalence of G6PD deficiency based on indirect enzyme assay was 6.10%, with 8.08% exhibiting intermediate deficiency. The developed high-resolution melting assays demonstrated excellent performance, achieving 100% sensitivity and specificity in detecting G6PD alleles compared with Sanger sequencing. Genotypic variations were observed across four geographic locations, with the combination of c.1311C>T and c.1365-13T>C being the most common genotype. Compound mutations, notably G6PD Viangchan (c.871G>A, c.1311C>T and c.1365-13T>C), accounted for 15.26% of detected mutations. The high-resolution melting assays also identified the double mutation G6PD Chinese-4 + Canton and G6PD Radlowo, a variant found for the first time in Thailand. Biochemical and structural characterisation revealed that these variants significantly reduced catalytic activity by destabilising protein structure, particularly in the case of the Radlowo mutation. The refinement of these high-resolution melting assays presents a highly accurate and high-throughput platform that can improve patient care by enabling precise diagnosis, supporting genetic counselling and guiding public health efforts to manage G6PD deficiency-especially crucial in malaria-endemic regions where 8-aminoquinoline therapies pose a risk to deficient individuals.

Epidemiology of glucose-6-phosphate dehydrogenase deficiency in 10 malaria-endemic countries in sub-Saharan Africa: a systematic review

Introduction

it is now clear that several antimalarials, such as primaquine, can cause severe hemolytic anemia in people with G6PD deficiency. Prescriptions for antimalarials should consider G6PD status, especially in malaria-endemic areas. The frequency of G6PD is quite high in some countries in sub-Saharan Africa.

Methods

a systematic review was conducted to summarize the findings on the G6PD deficiency epidemiology in the ten African nations most impacted by malaria. We conducted a systematic electronic literature search based on eligibility requirements using databases, PubMed, Google Scholar, and ScienceDirect. The chosen studies are original or primary studies published in English or French and evaluate the prevalence of G6PD deficiency or its incidence, in a peer-reviewed scientific journal during the interval of time 2000-2023 were included in this review. The systematic review was carried out by using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses).

Results

after being screened, 19 complete texts were deemed appropriate for extracting data. The prevalence of G6PD deficiency varied among these ten African countries, ranging from <1% to 23.9%, with a considerable dominance when it comes to men in comparison with women.

Conclusion

to avoid morbidity and mortality among the population in the affected areas, several regions in African countries must review their diagnostic and screening protocols to detect deficiency in G6PD to make proper interventions in time.

Determination of the Phytochemical Components, Nutritional Content, Biological Activities, and Cytotoxicity of Ripening Karanda (Carissa carandas) Fruit Extract for Functional Food Development

Ripening karanda fruits are a natural source of phytochemicals, which exhibit various biological properties. The present study aimed to determine the types of phytochemicals, biological properties, and cytotoxic and hemolytic effects of ripening karanda fruits. Two mechanical tools were used to collect the phytochemicals under low temperatures during the extraction process. The extracts were investigated for antioxidants using a 2,2-diphenyl-1-picrylhydrazyl assay. The total phenolic contents were studied using the Folin-Ciocalteu method. The phytochemicals of the total extract were analyzed by gas column chromatography-mass spectrometry. The saccharide types, including the total sugar content, were determined using thin-layer chromatography and the Lane-Eynon method. The total ascorbic acid was analyzed in accordance with the AOAC 967.21 method. The cytotoxic and hemolytic effects of phytochemicals were investigated using human peripheral blood mononuclear cells (hPBMCs) and human red blood cells (hRBCs). The results showed that the appropriation for repeated ultrasonic extraction is four times. The fresh ripening karanda fruit (Fresh-RKF) and freeze-dried powder of ripening karanda fruit extracts exhibited antioxidant activity in vitro and exerted a noncytotoxic effect on hPBMCs at a concentration of ≤2.5 mg/mL and a hemolytic effect on hRBCs at a concentration of >5.0 mg/mL. The Fresh-RKF extract comprised 0.27% of total sugar and 0.01% of ascorbic acid. These data could support the development of supplemental foods using ripening karanda fruits as the primary ingredient.

Revealing the secrets of Blue Zones

Aging is influenced by cellular senescence mechanisms that are associated with oxidative stress. Oxidative stress is the imbalance between antioxidants and free radicals. This imbalance affects enzyme activities and causes mitochondrial dysfunction. It also slows down cellular energy production and disrupts cellular homeostasis. Additionally, oxidative stress stimulates inflammation, increases the number of point mutations, and alters intercellular communication. It can lead to epigenetic alterations, genomic instability, telomere attrition, and loss of proteostasis. Ultimately, these factors contribute to aging and the development of chronic diseases. Glucose-6-phosphate dehydrogenase (G6PD) is an antioxidant enzyme that protects cells from oxidative and nitrosative damage. It helps restore redox balance, preserve macromolecule function, and rescue cells from cellular senescence, autophagy, and stress-induced apoptosis. G6PD is considered an anti-senescence enzyme. The World Health Organization classifies G6PD variants into five groups based on the enzyme's residual activity. The first four classes are categorized according to the degree of G6PD deficiency, while the fifth class includes variants with enzyme activities greater than normal. Increased G6PD activity does not exhibit clinical manifestations. Consequently, the full spectrum of mutations and the prevalence of increased G6PD activity in the population remain unknown. The world's oldest and healthiest people live in Blue Zones. These comprise isolated populations, and there may be a geographic prevalence of high-activity G6PD variants that protect against oxidative stress-induced senescence. To uncover the secret of centenarians' longevity, additional research is needed to determine whether the hidden factor is the increased activity of the G6PD enzyme.

Genetic variation features of neonatal hyperbilirubinemia caused by inherited diseases

BACKGROUND

Genetic factors play an important role in neonatal hyperbilirubinemia (NH) caused by genetic diseases.

AIM

To explore the characteristics of genetic mutations associated with NH and analyze the correlation with genetic diseases.

METHODS

This was a retrospective cohort study. One hundred and five newborn patients diagnosed with NH caused by genetic diseases were enrolled in this study between September 2020 and June 2023 at the Second Affiliated Hospital of Xiamen Medical College. A 24-gene panel was used for gene sequencing to analyze gene mutations in patients. The data were analyzed via Statistical Package for the Social Sciences 20.0 software.

RESULTS

Seventeen frequently mutated genes were found in the 105 patients. Uridine 5'-diphospho-glucuronosyltransferase 1A1 (UGT1A1) variants were identified among the 68 cases of neonatal Gilbert syndrome. In patients with sodium taurocholate cotransporting polypeptide deficiency, the primary mutation identified was Na+/taurocholate cotransporting polypeptide Ntcp (SLC10A1). Adenosine triphosphatase 7B (ATP7B) mutations primarily occur in patients with hepatolenticular degeneration (Wilson's disease). In addition, we found that UGT1A1 and glucose-6-phosphate dehydrogenase mutations were more common in the high-risk group than in the low-risk group, whereas mutations in SLC10A1, ATP7B, and heterozygous 851del4 mutation were more common in the low-risk group.

CONCLUSION

Genetic mutations are associated with NH and significantly increase the risk of disease in affected newborns.

NFE2L2 and ferroptosis resistance in cancer therapy

NFE2-like basic leucine zipper transcription factor 2 (NFE2L2, also known as NRF2), is a key transcription factor in the cellular defense against oxidative stress, playing a crucial role in cancer cell survival and resistance to therapies. This review outlines the current knowledge on the link between NFE2L2 and ferroptosis - a form of regulated cell death characterized by iron-dependent lipid peroxidation - within cancer cells. While NFE2L2 activation can protect normal cells from oxidative damage, its overexpression in cancer cells contributes to drug resistance by upregulating antioxidant defenses and inhibiting ferroptosis. We delve into the molecular pathways of ferroptosis, highlighting the involvement of NFE2L2 and its target genes, such as NQO1, HMOX1, FTH1, FTL, HERC2, SLC40A1, ABCB6, FECH, PIR, MT1G, SLC7A11, GCL, GSS, GSR, GPX4, AIFM2, MGST1, ALDH1A1, ALDH3A1, and G6PD, in ferroptosis resistance. Understanding the delicate balance between NFE2L2's protective and deleterious roles could pave the way for novel therapeutic strategies targeting NFE2L2 to enhance the efficacy of ferroptosis inducers in cancer therapy.

Molecular epidemiological characteristics, variant spectrum and genotype-phenotype correlation of glucose-6-phosphate dehydrogenase deficiency in China: A population-based multicenter study using newborn screening

BACKGROUND AND AIMS

Newborn screening (NBS) for glucose-6-phosphate dehydrogenase (G6PD) deficiency by biochemical tests is being used worldwide, however, the outcomes arising from combined genetic and biochemical tests have not been evaluated. This research aimed to evaluate the outcomes of application of combined genetic and biochemical NBS for G6PD deficiency and to investigate the molecular epidemiological characteristics, variant spectrum, and genotype-phenotype correlation of G6PD deficiency in China.

METHODS

A population-based cohort of 29,601 newborns were prospectively recruited from eight NBS centers in China between February 21 and December 30, 2021. Biochemical and genetic NBS was conducted simultaneously.

RESULTS

The overall prevalence of G6PD deficiency was 1.12% (1.86% for male, and 0.33% for female; 1.94% for South China and 0.08% for North China). Genetic NBS identified 10 male patients undetected by biochemical NBS. The overall positive predictive values (PPVs) of biochemical and genetic NBS were 79.95% and 47.57%, respectively. A total of 15 variants were identified, with the six most common variants being c.1388G > A, c.1376G > T, c.95A > G, c.871G > A, c.1024C > T and c.392G > T (94.2%). The activity of G6PD was correlated with the type and WHO classification of variants.

CONCLUSION

This study highlighted that combined screening could enhance the efficiency of current NBS for diagnosing G6PD deficiency. The prevalence, variant spectrum and allele frequency of G6PD deficiency vary across different regions. Our data provide valuable references for clinical practice and optimization of future screening strategies for G6PD deficiency.

Rate of glucose-6-phosphate dehydrogenase deficiency in neonatal indirect hyperbilirubinemia at a private tertiary centre

OBJECTIVES

To investigate the rate of hospitalized neonates with glucose-6-phosphate dehydrogenase (G6PD) deficiency presented with indirect hyperbilirubinemia at a private tertiary center in Al-Ahsa, Saudi Arabia, over 4 years and to compare the characteristics of G6PD-deficient and normal neonates admitted for indirect hyperbilirubinemia.

METHODS

The retrospective case control study was carried out at Almoosa Specialist Hospital, Al-Ahsa, Saudi Arabia. Data were collected from Yassasi Medical System from 2018-2021 and finalized in 2024. The study included 2 groups: G6PD-normal and G6PD-deficient neonates with indirect hyperbilirubinemia not having recognizable triggers of hemolysis. The analysis focused on serum bilirubin levels, direct bilirubin levels, hematocrit levels, hemoglobin levels, reticulocyte percentage, G6PD levels, duration of phototherapy, and the need for exchange transfusion.

RESULTS

The study enrolled 3200 neonates with hyperbilirubinemia, of whom 274 met inclusion criteria. A total of 103 (37.6%) neonates were G6PD-deficient, with 77 (74.8%) being male and 26 (25.2%) female. Glucose-6-phosphate dehydrogenase-deficient neonates exhibited significantly higher initial total bilirubin levels and earlier sampling times. There was no significant correlation between G6PD deficiency and hematocrit or hemoglobin levels in hyperbilirubinemic neonates, but 4 neonates required exchange transfusion, demonstrating statistical significance (p=0.009).

CONCLUSION

High rate of G6PD deficiency in neonates with indirect hyperbilirubinemia, requiring close monitoring to prevent exchange transfusions, with no significant differences in hematocrit or hemoglobin levels.

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.

Implementation of Universal Screening for G6PD Deficiency in Newborns

We describe the implementation of universal glucose-6-phosphate dehydrogenase (G6PD) screening during the first year of New York State mandated testing, as well as operational challenges and clinical knowledge gained. All infants born at or transferred to our center between June 21, 2022 and June 30, 2023, underwent testing for G6PD enzyme deficiency and were included in the study cohort. Infant blood samples were collected and sent to a reference laboratory for quantitative assay. After initiation of universal screening, a quality improvement initiative was launched to: monitor and improve the suitability of blood sample collection to ensure timely return of results;improve the reliability and validity of the reference laboratory enzyme assay; andestablish accurate reference ranges for G6PD deficiency in newborns.A total of 5601 newborns were included. Within the first year of implementation, the percentage of samples yielding any test result increased from 76% to 85%, and most patients had a G6PD result available within 1 day of discharge. We established a more accurate threshold for G6PD deficiency in newborns of <4.9 U/g Hb and G6PD intermediate of <10.0 U/g Hb. Using the updated reference ranges, 224 patients in our cohort were identified as G6PD deficient or intermediate (4.0%). Through a quality-sensitive process, we identified the importance of a standardized approach, improved sample collection processes, decreased sample turnaround time, and established more accurate reference ranges. We hope our experiences will help others seeking to improve processes and implement similar programs at other institutions.

Glucose-6-phosphate dehydrogenase deficiency and neonatal indirect hyperbilirubinemia: a retrospective cohort study among 40,305 consecutively born babies

BACKGROUND AND OBJECTIVE

Glucose-6-phosphate dehydrogenase deficiency (G6PDD) being highly prevalent in the Middle East, the primary objective was to estimate the incidence of neonatal jaundice among G6PD-deficient neonates and to explore its association with various risk factors.

METHODS

This retrospective cohort study includes 7 years data of neonates diagnosed with G6PDD between 1st January 2015, and 30 September 2022, from Al Wakra Hospital, HMC Qatar.

RESULTS

Among the 40,305 total births, 1013 had G6PDD with an incidence of 2.51%. Of all the G6PDD babies, 24.6% (249/1013) received phototherapy and three babies required exchange transfusion. Statistically significant associations were noted between the need for phototherapy and gestational age, gestational age groups, birth weight, and birth weight groups, but logistic regression analysis showed significant association for phototherapy only with the gestational age group.

CONCLUSION

Universal screening and proper follow-up is essential for G6PDD as it plays crucial role in neonatal jaundice.

Glucose-6-phosphate dehydrogenase deficiency as a cause for nonimmune hydrops fetalis and severe fetal anemia: A systematic review

BACKGROUND

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked recessive disorder that predisposes individuals to hemolysis due to an inborn error of metabolism. We performed a systematic literature review to evaluate G6PD deficiency as a possible etiology of nonimmune hydrops fetalis (NIHF) and severe fetal anemia.

METHODS

PubMed, OVID Medline, Scopus, and clinicaltrials.gov were queried from inception until 31 April 2023 for all published cases of NIHF and severe fetal anemia caused by G6PD deficiency. Keywords included "fetal edema," "hydrops fetalis," "glucose 6 phosphate dehydrogenase deficiency," and "fetal anemia." Cases with workup presuming G6PD deficiency as an etiology for NIHF and severe fetal anemia were included. PRISMA guidelines were followed.

RESULTS

Five cases of G6PD-related NIHF and one case of severe fetal anemia were identified. Four fetuses (4/6, 66.7%) were male and two fetuses (2/6, 33.3%) were female. Mean gestational age at diagnosis of NIHF/anemia and delivery was 32.2 ± 4.9 and 35.7 ± 2.4 weeks, respectively. Four cases (66.7%) required a cordocentesis for fetal transfusion, and two cases (33.3%) received blood transfusions immediately following delivery. Among the four multigravida cases, two (50%) noted previous pregnancies complicated by neonatal anemia. When reported, the maternal cases included two G6PD deficiency carrier patients and two G6PD-deficient patients. Exposures to substances known to cause G6PD deficiency-related hemolysis occurred in 3/6 (50%) cases.

CONCLUSION

Six cases of NIHF/severe fetal anemia were associated with G6PD deficiency. While G6PD deficiency is an X-linked recessive condition, female fetuses can be affected. Fetal G6PD deficiency testing can be considered if parental history indicates, particularly if the standard workup for NIHF is negative.

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 of Glucose-6-Phosphate Dehydrogenase Deficiency in Male Newborn Infants and Its Relationship with Neonatal Jaundice in Thailand

OBJECTIVE

The study aimed to explore the prevalence of glucose-6-phosphate dehydrogenase (G-6-PD) deficiency among male newborn infants in northeastern Thailand and its relationship with neonatal jaundice (NJ).

STUDY DESIGN

This prospective cohort study included male newborn infants with gestational age (GA) ≥35 weeks born between July 1, 2019, and March 1, 2021. Cord blood was sent for G-6-PD fluorescent spot test (FST) and results were reported as normal, partial, or complete deficiency. Infants with NJ would have blood tested for total serum bilirubin (TSB) level and other possible causes of NJ. Duration of phototherapy, length of hospital stays, and complications were documented.

RESULTS

There were 922 male infants included in this study with 854 (93.1%) term and 63 (6.9%) preterm infants. FST showed 132 infants (14.4%) had G-6-PD deficiency. Incidence of NJ was significantly higher among infants with G-6-PD deficiency compared with infants with normal G-6-PD level (47.7 vs. 25.8%; relative risk [RR]: 2.62, 95% confidence interval [CI]: 1.79-3.82; p < 0.001). Regardless of G-6-PD level, preterm infants had significantly higher incidence of NJ than term infants (52.4 vs. 27.3%; RR: 2.93, 95% CI: 1.75-4.92; p < 0.001). Duration of phototherapy was significantly longer in infants with G-6-PD deficiency with NJ but hospital stays were similar. Infants with combined G-6-PD deficiency and other causes of hemolysis did not have higher TSB level than infants with isolated G-6-PD deficiency. Risk factors associated with NJ were G-6-PD deficiency and preterm infants, whereas more advance GA was associated with reduced risk for NJ.

CONCLUSION

G-6-PD deficiency and preterm infants were important risk factors for NJ. Routine G-6-PD screening, close monitoring for signs of NJ in infant with risks, and appropriate parental counseling should be implemented.

KEY POINTS

· G-6-PD deficiency increases risk of neonatal jaundice.. · Preterm infants have higher risk for neonatal jaundice.. · G-6-PD deficiency does not link with severe jaundice..

Exploring the Protective Role of G6PD Deficiency in Aluminum Phosphide Poisoning: A Case Report and Review of the Literature

Aluminum phosphide (ALP) poisoning poses a significant public health concern worldwide, with a high mortality rate and no established definitive treatment. This case report highlights a 30-year-old male with G6PD deficiency who ingested ALP tablets, presenting with jaundice and anemia. Despite the severity of ALP poisoning, the concurrent G6PD deficiency appeared to confer a protective effect, potentially mitigating complications. Laboratory investigations revealed characteristic findings, including unconjugated hyperbilirubinemia and normocytic hypochromic anemia. Treatment involved supportive measures and transfusion, leading to clinical improvement and discharge. The discussion focuses on the pathophysiology of G6PD deficiency and its protective role against ALP poisoning, supported by a literature review and experimental evidence. Moreover, potential therapeutic interventions targeting oxidative stress are discussed. This case underscores the importance of considering G6PD deficiency in ALP poisoning management and highlights avenues for further research into protective mechanisms and treatment strategies.

[The effect of glucose-6-phosphate dehydrogenase deficiency on allogeneic hematopoietic stem cell transplantation in patients with hematological disorders]

Objectives: To determine the effect of glucose-6-phosphate-dehydrogenase (G6PD) deficiency on patients' complications and prognosis following allogeneic stem cell hematopoietic transplantation (allo-HSCT) . Methods: 7 patients with G6PD deficiency (study group) who underwent allo-HSCT at Peking University People's Hospital from March 2015 to January 2021 were selected as the study group, and thirty-five patients who underwent allo-HSCT during the same period but did not have G6PD deficiency were randomly selected as the control group in a 1∶5 ratio. Gender, age, underlying diseases, and donors were balanced between the two groups. Collect clinical data from two patient groups and perform a retrospective nested case-control study. Results: The study group consisted of six male patients and one female patient, with a median age of 37 (range, 2-45) years old. The underlying hematologic diseases included acute myeloid leukemia (n=3), acute lymphocytic leukemia (n=2), and severe aplastic anemia (n=2). All 7 G6PD deficiency patients achieved engraftment of neutrophils within 28 days of allo-HSCT, while the engraftment rate of neutrophils was 94.5% in the control group. The median days of platelet engraftment were 21 (6-64) d and 14 (7-70) d (P=0.113). The incidence rates of secondary poor graft function in the study group and control group were 42.9% (3/7) and 8.6% (3/35), respectively (P=0.036). The CMV infection rates were 71.4% (5/7) and 31.4% (11/35), respectively (P=0.049). The incidence rates of hemorrhagic cystitis were 57.1% (4/7) and 8.6% (3/35), respectively (P=0.005), while the bacterial infection rates were 100% (7/7) and 77.1% (27/35), respectively (P=0.070). The infection rates of EBV were 14.3% (1/7) and 14.3% (5/35), respectively (P=1.000), while the incidence of fungal infection was 14.3% (1/7) and 25.7% (9/35), respectively (P=0.497). The rates of post-transplant lymphoproliferative disease (PTLD) were 0% and 5.7%, respectively (P=0.387) . Conclusions: The findings of this study indicate that blood disease patients with G6PD deficiency can tolerate conventional allo-HSCT pretreatment regimens, and granulocytes and platelets can be implanted successfully. However, after transplantation, patients should exercise caution to avoid viral infection, complications of hemorrhagic cystitis, and secondary poor graft function.

Propensity score matched analysis and risk stratification of donors with G6PD deficiency in living donor liver transplantation

INTRODUCTION

Glucose 6 phosphate dehydrogenase (G6PD) deficiency (G6PDd) can trigger hemolysis following surgical stress. Differentiating G6PDd-related post-operative hemolytic episodes (PHE) and post-hepatectomy liver failure may be challenging especially in living donors where donor safety is paramount. We analysed outcomes of our cohort of G6PDd liver donors.

METHODS

G6PDd individuals with no evidence of hemolysis were considered as living donors if there was no alternative family donor. Outcomes of G6PDd donors undergoing left lateral/left lobe donation (Group LL) and right lobe donation (Group RL) were compared with non-G6PDd donors matched in a 1:3 ratio using propensity score matching.

RESULTS

59 G6PDd donors (5.8% of 1011) underwent living donor hepatectomy (LiDH) during the study period. LL-G6PDd donors (22.37%) had higher post-operative peak bilirubin level compared to matched controls, but no difference in morbidity or need for post-operative blood transfusion.RL-G6PDd donors (37.63%) had higher peak bilirubin level, morbidity (16.2% vs. 3.6%, p = 0.017) and more post-operative blood transfusion (21.6% vs. 6.4%, p = 0.023) as compared to matched non-G6PDd cohort. Four RL-G6PDd donors (10.8%) developed PHE. Low G6PD activity (15% vs. 40%, p = 0.034) and lower future liver remnant (FLR) (34.3% vs. 37.8%, p = 0.05) were identified as risk factors for PHE.

CONCLUSION

We report the largest to-date series of G6PDd individuals undergoing LiDH and confirm the safety of LL donation in G6PDd. Our analysis identifies specific risk factors for PHE and suggests that right lobe LiDH be avoided in individuals with less than 25% G6PD activity when the FLR is less than 36%.

Newborn screening for G6PD deficiency in HeFei, FuYang and AnQing, China: Prevalence, cut-off value, variant spectrum

Background

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked recessive Mendelian genetic disorder characterized by neonatal jaundice and hemolytic anemia, affecting more than 400 million people worldwide. The purpose of this research was to investigate prevalence rates of G6PD deficiency and to evaluate and establish specific cut-off values in early prediction of G6PD deficiency by regions (HeFei, FuYang, AnQing) on different seasons, as well as to investigate the frequencies of G6PD gene mutations among three regions mentioned above.

Methods

A total of 31,482 neonates (21,402, 7680, and 2340 for HeFei, FuYang, and AnQing cities, respectively) were recruited. Positive subjects were recalled to attend genetic tests for diagnosis. G6PD activity on the Genetic screening processor (GSP analyzer, 2021-0010) was measured following the manufactureržs protocol. The cut-off value was first set to 35 U/dL. The receiver operating characteristics (ROC) curve was employed to assess and compare the efficiency in predicting G6PD deficiency among HeFei, FuYang, and AnQing cities in different seasons.

Molecular epidemiological investigation of G6PD deficiency in Yangjiang region, western Guangdong province

Objectives: The prevalence of G6PD deficiency has not been reported in Yangjiang, a western city in Guangdong province. This study aims to investigate the molecular characteristics of G6PD deficiency in this region. Methods: Blood samples were collected from adults at a local hospital to screen for G6PD deficiency. The deficient samples were subjected to further analysis using PCR and reverse dot blot to determine the specific G6PD variants. Results: Among the 3314 male subjects, 250 cases of G6PD deficiency were found using the G6PD enzyme quantitative assay, resulting in a prevalence of 7.54% (250/3314) in the Yangjiang region. The prevalence of G6PD deficiency in females was 3.42% (176/5145). Out of the 268 cases of G6PD deficiency tested for G6PD mutations, reverse dot blot identified 20 different G6PD variants. The most common G6PD variant was c.1388G>A (81/268), followed by c.1376G>T (48/268), c.95A>G (32/268), c.1024C>T (9/268), c.392G>T (7/268), and c.871G>A/c.1311C>T (6/268). It was observed that c.871G>A was always linked to the polymorphism of c.1311C>T in this population. Conclusion: This investigation into G6PD deficiency in this area is expected to significantly improve our understanding of the prevalence and molecular characterization of this condition.

The correlation between serum total bile acid and alanine aminotransferase of pregnant women and the disorders of neonatal hyperbilirubinemia-related amino acid metabolism

BACKGROUND

To explore the association between liver metabolism-related indicators in maternal serum and neonatal hyperbilirubinemia (NHB), and further investigate the predictive value of these indicators in NHB-related amino acid metabolism disorders.

METHODS

51 NHB and 182 No-NHB newborns and their mothers who treated in the Fourth Hospital of Shijiazhuang from 2018 to 2022 were participated in the study. The differences in clinical data were compared by the Mann-Whitney U test and Chi-square test. Multivariate logistic regression was used to analyze the relationship between maternal serum indicators and the occurrence of NHB. The correlation analysis and risk factor assessment of maternal serum indicators with NHB-related amino acid metabolic disorders were performed using Spearman correlation analysis and multivariate logistic regression.

RESULTS

Compared to the non NHB group, the NHB group had higher maternal serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), ALT/AST, and total bile acid (TBA), while lower levels of serum albumin (ALB), total cholesterol (TC) and high-density lipoprotein (HDL). The levels of alanine (ALA), valine (VAL), ornithine (ORN), and proline (PRO) in the newborns were reduced in NHB group, while arginine (ARG) showed a tendency to be elevated. Multiple logistic regression analysis showed that maternal ALT, AST, ALT/AST, and TBA levels were all at higher risk with the development of NHB, whereas ALB, TC, and HDL levels were negatively associated with NHB development. Increasing maternal TBA level was associated with lower ALA (r=-0.167, p = 0.011), VAL (r=-0.214, p = 0.001), ORN (r=-0.196, p = 0.003), and PRO in the newborns (r=-0.131, p = 0.045). Maternal ALT level was negatively associated with ALA (r=-0.135, p = 0.039), VAL (r=-0.177, p = 0.007), ORN (r=-0.257, p < 0.001), while ALT/AST was positively correlated with ARG (r = 0.133, p = 0.013). After adjustment for confounding factors, maternal serum TBA and ALT were the independent risk factor for neonatal ORN metabolic disorders [(adjusted odds ratio (AOR) = 0.379, 95%CI = 0.188-0.762, p = 0.006), (AOR = 0.441, 95%CI = 0.211-0.922, p = 0.030)]. Maternal ALT level was an independent risk factor for neonatal VAL metabolic disorders (AOR = 0.454, 95%CI = 0.218-0.949, p = 0.036).

CONCLUSIONS

The levels of high TBA, ALT, AST, and low HDL, TC of maternal were associated with the risk of NHB. Maternal TBA and ALT levels were independent risk factors for NHB-related amino acid disturbances which have value as predictive makers.

Screening results and mutation frequency analysis of G6PD deficiency in 1,291,274 newborns in Huizhou, China: a twenty-year experience

OBJECTIVES

This study aimed to investigate the incidence rate and spectrum of gene mutations of Glucose-6-phosphate dehydrogenase (G6PD) deficiency in the Huizhou city of southern China to provide a scientific basis for disease prevention and control in the area.

METHODS

From March 2003 to December 2022, newborn screening for G6PD enzyme activity was carried out in Huizhou city using the fluorescence quantitative method. Infants who tested positive during the initial screening were diagnosed using the nitroblue tetrazolium ratio method, while a subset of infants received further gene mutation analysis using the multicolor probe melting curve analysis method.

RESULTS

A total of 1,291,274 newborns were screened and the screening rate has increased from 20.39% to almost 100%. In the 20-year period, 57,217 (4.43%) infants testing positive during the initial screening. Out of these infants, 49,779 (87%) were recalled for confirmatory testing. G6PD deficiency was confirmed in 39,261 of the recalled infants, indicating a positive predictive value of 78.87%. The estimated incidence rate of G6PD deficiency in the region was 3.49%, which was significantly higher than the average incidence rate of 2.1% in southern China. On the other hand, seven pathogenic G6PD variants were identified in the analysis of the 99 diagnosed infants with the most common being c.1388 G > A (48.5%), followed by c.95 A > G (19.2%), c.1376 G > T (15.2%), c.871 G > A (9.1%), c.1360 C > T (3.0%), c.392 G > T (3.0%), and c.487 G > A (1.0%).

CONCLUSION

The incidence of G6PD deficiency in newborns in the Huizhou city was higher than the southern China average level, while the types and frequencies of gene mutations were found to vary slightly from other regions. Our findings suggested that free government screening and nearby diagnosis strategies could reduce the incidence of G6PD deficiency in the area.

G6PD gene detection in neonatal hyperbilirubinemia and analysis of related risk factors

BACKGROUND

Hyperbilirubinemia is a common disorder in neonates, with premature infants at higher risk of developing the disorder.

OBJECTIVE

Glucose-6-phosphate dehydrogenase (G6PD) gene detection was used to determine the incidence of G6PD deficiency and analyze the etiologies of G6PD deficiency in neonates with hyperbilirubinemia in the Zunyi region with the aim of providing scientific evidence for the clinical diagnosis and treatment.

METHODS

For the gene detection, 64 neonates with hyperbilirubinemia were selected as the observation group and 30 normal neonates were selected as the control group, and the risk factors for hyperbilirubinemia were investigated by using multivariate logistic regression analysis.

RESULTS

Among the neonates in the observation group, 59 cases had the G1388A mutation (92.19%) and 5 cases had the G1376T mutation (7.81%). No mutation was detected in the control group. In the observation group, the proportion of neonates who were born prematurely, with artificial feeding, with the age of starting feeding of more than 24 h, the time of first bowel movement of more than 24 h, premature rupture of membranes, infection, scalp hematoma, and perinatal asphyxia was higher than that in the control group, and the difference was statistically significant (p< 0.05). Multivariate logistic regression analysis showed that prematurity, infection, scalp hematoma, perinatal asphyxia, the age of starting feeding of more than 24 h, and the time of first bowel movement over 24 h were risk factors for the development of neonatal hyperbilirubinemia (p< 0.05).

CONCLUSION

The G1338A and G1376T mutations were important features of the genetics of neonatal hyperbilirubinemia, and genetic detection together with the prevention of prematurity, infection, scalp hematoma, perinatal asphyxia, the age of starting feeding, and the time of first bowel movement would help reduce the incidence of this disease.

Prevalence and molecular heterogeneity of glucose-6-phosphate dehydrogenase (G6PD) deficiency in the Senoi Malaysian Orang Asli population

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked genetic disorder characterized by reduced G6PD enzyme levels in the blood. This condition is common in populations exposed to malaria; an acute febrile disease caused by Plasmodium parasites. G6PD-deficient individuals may suffer from acute hemolysis following the prescription of Primaquine, an antimalarial treatment. The population at risk for such a condition includes the Senoi group of Orang Asli, a remote indigenous community in Malaysia. This study aimed to elucidate the G6PD molecular heterogeneity in this subethnic group which is important for malaria elimination. A total of 662 blood samples (369 males and 293 females) from the Senoi subethnic group were screened for G6PD deficiency using a quantitative G6PD assay, OSMMR2000-D kit with Hb normalization. After excluding the family members, the overall prevalence of G6PD deficiency in the studied population was 15.2% (95% CI: 11-19%; 56 of 369), with males (30 of 172; 17.4%) outnumbering females (26 of 197; 13.2%). The adjusted male median (AMM), defined as 100% G6PD activity, was 11.8 IU/gHb. A total of 36 participants (9.6%; 26 male and 10 female) were deficient (<30% of AMM) and 20 participants (5.4%; 4 male and 16 female) were G6PD-intermediate (30-70% of AMM). A total of 87 samples were genotyped, of which 18 showed no mutation. Seven mutations were found among 69 genotyped samples; IVS11 T93C (47.1%; n = 41), rs1050757 (3'UTR +357A>G)(39.1%; n = 34), G6PD Viangchan (c.871G>A)(25.3%; n = 22), G6PD Union (c.1360C>T)(21.8%; n = 19), c.1311C>T(20.7%; n = 18), G6PD Kaiping (c.1388G>A)(8.0%; n = 7), and G6PD Coimbra (c.592C>T)(2.3%; n = 2). Our analysis revealed 27 hemizygote males, 18 heterozygote females, 7 homozygote females, and 2 compound heterozygote females. This study confirms the high prevalence of G6PD deficiency among the Senoi Malaysian Orang Asli, with a significant degree of molecular heterogeneity. More emphasis should be placed on screening for G6PD status and proper and safe use of Primaquine in the elimination of malaria among this indigenous population.

Early-Term Neonates Demonstrate a Higher Likelihood of Requiring Phototherapy Compared to Those Born Full-Term

Early-term neonates (with a gestational age (GA) of 37 and 0/7 weeks to 38 and 6/7 weeks) face higher morbidities, including respiratory and neurodevelopmental issues, than full-term (39 and 0/7 weeks to 40 and 6/7 weeks) infants. This study explores whether hyperbilirubinemia necessitating phototherapy also differs between these groups. A retrospective study was conducted on neonates born from January 2021-June 2022, excluding those with specific conditions. Evaluated factors included GA, birth weight, bilirubin levels, glucose-6-phosphate dehydrogenase (G6PD) deficiency, and feeding type, with phototherapy given as per AAP guidelines. Of 1085 neonates, 356 met the criteria. When stratifying the neonates based on the need for phototherapy, a higher proportion of early-term neonates required phototherapy compared to full-term (p < 0.05). After factoring in various risks (GA; birth weight; gender; feeding type; G6PD deficiency; transcutaneous bilirubin levels at 24 h and 24-48 h postpartum; maternal diabetes; and the presence of caput succedaneum or cephalohematoma), early-term neonates were more likely to need phototherapy than full-term babies (OR: 2.15, 95% CI: 1.21 to 3.80). The optimal cut-off for transcutaneous bilirubin levels 24-48 h postpartum that were used to predict phototherapy need was 9.85 mg/dl. In conclusion, early-term neonates are at a greater risk for developing jaundice and requiring phototherapy than full-term neonates. Monitoring bilirubin 24-48 h postpartum enhances early prediction and intervention.

Epidemiology of Glucose-6-Phosphate Dehydrogenase Deficiency in Arab Countries: Insights from a Systematic Review

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common metabolic disorder affecting more than 400 million individuals worldwide. Being an X-linked disorder, the disease is more common among males than females. Various Arab countries estimated the prevalence of G6PD deficiency; however, findings from different countries have not been synthesized collectively. Hence, a systematic review was undertaken to synthesize the findings on the epidemiology of G6PD deficiency in all Arab countries. We performed an electronic systematic literature search based on the eligibility criteria using databases, including MEDLINE, Embase, and CINHAL. The studies included in the review were primary and original research studies assessing the prevalence or incidence, risk factors, or determinants of G6PD deficiency, and published in the English language in a peer-reviewed scientific journal between 2000 and 2022. The systematic review was carried out with the help of an updated PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) checklist. After the screening, 23 full texts were finalized for data extraction. The prevalence of G6PD deficiency ranged from 2 to 31% with a greater burden among high-risk populations like neonates with sickle cell anemia. The determinants included males, family history, consanguineous marriages, and geographic regions, which were all risk factors, except for body weight, which was a protective factor. The prevalence of G6PD deficiency varies across Arab countries, with a higher prevalence in males than females. Different regions of Arab countries need to revisit their screening and diagnostic guidelines to detect G6PD deficiency promptly and prevent unnecessary morbidity and mortality among their communities.

Etiology analysis and G6PD deficiency for term infants with jaundice in Yangjiang of western Guangdong

OBJECTIVE

Glucose 6-phosphate dehydrogenase (G6PD) deficiency increases the risk of neonatal hyperbilirubinemia. The aim of this study is to evaluate the risk factors associated with hyperbilirubinemia in infants from the western part of Guangdong Province, and to assess the contribution of G6PD deficiency to neonatal jaundice.

METHODS

The term infants with neonatal hyperbilirubinemia in People's Hospital of Yangjiang from June 2018 to July 2022 were recruited for the retrospective analysis. All the infants underwent quantitative detection of the G6PD enzyme. The etiology was determined through laboratory tests and clinical manifestations.

RESULTS

Out of 1,119 term infants, 435 cases presented with jaundice. For the etiology analysis, infection was responsible for 16.09% (70/435), G6PD deficiency accounted for 9.66% (42/435), of which 3 were complicated with acute bilirubin encephalopathy), bleeding accounted for 8.05% (35/435), hemolytic diseases accounted for 3.45% (15/435), and breast milk jaundice accounted for 2.53% (11/435). One case (0.23%) was attributed to congenital hypothyroidism, multiple etiologies accounted for 22.3% (97/435), and 35.63% (155/435) were of unknown etiology. Of the jaundiced infants, 19.54% (85/435) had G6PD deficiency, while only 10.23% (70/684) of non-jaundiced infants had G6PD deficiency; this difference was found to be statistically significant (P < 0.001). Furthermore, the hemoglobin levels in the jaundiced infants with G6PD deficiency (146.85 ± 24.88 g/L) were lower than those without G6PD deficiency (156.30 ± 22.07 g/L) (P = 0.001). 65 jaundiced infants with G6PD deficiency underwent G6PD mutation testing, and six different genotypes were identified, including c.95A > G, c.392G > T, c.1024C > T, c.1311C > T, c.1376G > T, c.1388G > A, c.871G > A/c.1311C > T, c.392G > T/c.1388G > A, and c.1376G > T/c.1311C > T.65iciency.

CONCLUSION

In newborns in Yangjiang, G6PD deficiency, infection, and neonatal hemolytic disease were identified as the main causes of hyperbilirubinemia and acute bilirubin encephalopathy. Specifically, Hemolytic factors in infants with G6PD deficiency may lead to reduced hemoglobin and increased bilirubin levels in jaundiced infants.

Population screening for glucose-6-phosphate dehydrogenase deficiency using quantitative point-of-care tests: a systematic review

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked hereditary disorder and a global public health concern that is most prevalent in malaria-endemic regions including Asia, Africa, and the Mediterranean. G6PD-deficient individuals are at high risk of developing acute hemolytic anemia following treatment with antimalarial drugs including Primaquine and Tafenoquine. However, the currently available tests for G6PD screening are complex and often have been misclassifying cases, particularly for females with intermediate G6PD activity. The latest innovation of quantitative point-of-care (POC) tests for G6PD deficiency provides an opportunity to improve population screening and prevent hemolytic disorders when treating malaria. Aim(s): To assess the evidence on the type and performance of quantitative point-of-care (POC) tests for effective G6PD screening and hence, radical elimination of Plasmodium malaria infections. Methods: Relevant studies published in English language confined from two databases, Scopus and ScienceDirect were searched from November 2016 onwards. The search was conducted using keywords including "glucosephosphate dehydrogenase" or "G6PD", "point-of-care", "screening" or "prevalence", "biosensor" and "quantitative". The review was reported following the PRISMA guidelines. Results: Initial search results yielded 120 publications. After thorough screening and examination, a total of 7 studies met the inclusion criteria, and data were extracted in this review. Two types of quantitative POC tests were evaluated, namely, the CareStart^TM Biosensor kit and the STANDARD G6PD kit. Both tests showed promising performance with high sensitivity and specificity ranging mostly from 72% to 100% and 92%-100%, respectively. The positive and negative predictive values (PPV and NPV) ranged from 35% to 72% and 89%-100%, with accuracy ranging from 86% to 98%. Conclusion: In areas with a high prevalence of G6PD deficiency that overlap with malaria endemicity, availability and validation of the diagnostic performance of quantitative POC tests are of absolute importance. Carestart™ biosensor and STANDARD G6PD kits showed high reliability and performed well in comparison to the spectrophotometric reference standard.

Severe G6PD deficiency leads to recurrent infections and defects in ROS production: Case report and literature review

Purpose: Severe glucose-6-phosphate dehydrogenase (G6PD) deficiency can lead to reduced nicotinamide adenine dinucleotide phosphate oxidase activity in phagocytes, resulting in immunodeficiency, with a limited number of reported cases. Here, we aimed to report a child with severe G6PD deficiency in China and investigate the mechanism of his recurrent infections.

Methods: The clinical manifestations and immunological phenotypes of this patient were retrospectively collected. Gene mutation was detected by whole-exome sequencing and confirmed by Sanger sequencing. Dihydrorhodamine (DHR) analysis was performed to measure the respiratory burst of neutrophils. Messenger ribonucleic acid and protein levels were detected in the patient under lipopolysaccharide stimulation by real-time quantitative reverse transcription polymerase chain reaction and Western blot. A review of the literature was performed.

Results: A male child with G6PD deficiency presented with recurrent respiratory infections, Epstein‒Barr virus infection and tonsillitis from 8 months of age. Gene testing revealed that the proband had one hemizygous mutation in the G6PD gene (c.496 C>T, p. R166C), inherited from his mother. This mutation might affect hydrophobic binding, and the G6PD enzyme activity of the patient was 0. The stimulation indexes of the neutrophils in the patient and mother were 22 and 37, respectively. Compared with healthy controls, decreased reactive oxygen species (ROS) production was observed in the patient. Activation of nuclear factor kappa-B (NF-κB) signaling was found to be influenced, and the synthesis of tumor necrosis factor alpha (TNF-α) was downregulated in the patient-derived cells. In neutrophils of his mother, 74.71% of the X chromosome carrying the mutated gene was inactivated. By performing a systematic literature review, an additional 15 patients with severe G6PD deficiency and recurrent infections were identified. Four other G6PD gene mutations have been reported, including c.1157T>A, c.180_182del, c.514C>T, and c.953_976del.

Conclusion: Severe G6PD deficiency, not only class I but also class II, can contribute to a chronic granulomatous disease-like phenotype. Decreased reactive oxygen species synthesis led to decreased activation of the NF-κB pathway in G6PD-deficient patients. Children with severe G6PD deficiency should be aware of immunodeficiency disease, and the DHR assay is recommended to evaluate neutrophil function for early identification.

Molecular heterogeneity of glucose-6-phosphate dehydrogenase deficiency in neonates in Wuhan: Description of four novel variants

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is one of the most common X-linked enzymopathies caused by G6PD gene variant. The aim of this study was to investigate the molecular epidemiological characteristic of the G6PD deficiency among newborn screening population in Wuhan region. A total of 430,806 healthy neonates in Wuhan area of China were screened for G6PD deficiency from November 2016 to December 2021. The positive samples were further detected with gene analysis. Among the 957 neonates with abnormal G6PD enzyme activity, the prevalence of G6PD deficiency in Wuhan was calculated as 0.22%. 38 genotypes were found and the top 5 frequencies of G6PD gene variants were c.1388G &gt; A, c.1376G &gt; T, c.95A &gt; G, c.1024C &gt; T and c.871G &gt; A. Seven rare single variants (c.25C &gt; T, c.152C &gt; T, c.406C &gt; T, c.497G &gt; A, c.679C &gt; T, c.854G &gt; A and c.1057C &gt; T) and two rare multiple variants (IVS-5 637/638T del/c.1311C &gt; T/1365-13T &gt; C and c.406C &gt; T/c.1311C &gt; T/1365-13T &gt; C) were discovered in this study. In addition, four novel variants (c.49C &gt; T, c.691G &gt; A, c.857A &gt; T and c.982G &gt; A) were detected out in our cohort, which have never been reported before. The result indicated that a rich diversity of G6PD genetic variants in Wuhan region, also had its own regional characteristic. Our data provided the basic knowledge for future prevention and research of G6PD deficiency and the findings will be useful for genetic counseling and prenatal diagnosis of G6PD deficiency in the Wuhan region.

Functional characterization of the p.(Gln195His) or Tainan and novel p.(Ser184Cys) or Toluca glucose-6-phosphate dehydrogenase (G6PD) gene natural variants identified through Mexican newborn screening for glucose-6-phosphate dehydrogenase deficiency

BACKGROUND

Newborn screening for glucose-6-phosphate dehydrogenase deficiency (G6PDd) was implemented in Mexico beginning in 2017. In a Mexican population, genotyping analysis of G6PD as a second-tier method identified a previously unreported missense variant, p.(Ser184Cys), which we propose to call "Toluca", and the extremely rare p.(Gln195His) or "Tainan" variant, which was previously described in the Taiwanese population as a Class II allele through in silico evaluations. Here, we sought to perform in vitro biochemical characterizations of the Toluca and Tainan G6PD natural variants and describe their associated phenotypes.

METHODS

The "Toluca" and "Tainan" variants were identified in three unrelated G6PDd newborn males, two of whom lacked evidence of acute hemolytic anemia (AHA) or neonatal hyperbilirubinemia (NHB). We constructed wild-type (WT), Tainan, and Toluca G6PD recombinant enzymes and performed in vitro assessments.

RESULTS

Both variants had diminished G6PD expression, decreased affinities for glucose-6-phosphate and NADP⁺ substrates, significant decreases in catalytic efficiency (∼97 % with respect to WT-G6PD), and diminished thermostabilities that were partially rescued by NADP⁺. In silico protein modeling predicted that the variants would have destabilizing effects on the protein tertiary structure, potentially reducing the enzyme half-lives and/or catalytic efficiencies.

CONCLUSION

Our data suggest that G6PD "Tainan" and "Toluca" are potential Class II natural variants, which agrees with the absence of chronic nonspherocytic hemolytic anemia (CNSHA) in our patients. It remains to be determined whether these variants represent high-risk genetic factors for developing CNSHA, AHA, and/or NHB.

Simultaneous detection of G6PD mutations using SNPscan in a multiethnic minority area of Southwestern China

Objectives: Baise, a multiethnic inhabited area of southwestern China, is a historical malaria-endemic area with a high prevalence of G6PD deficiency. However, few studies of G6PD deficiency have been conducted in this region. Therefore, we performed a genetic analysis of G6PD deficiency in the Baise population from January 2020 to June 2021. Methods: A SNPscan assay was developed to simultaneously detect 33 common Chinese G6PD mutations. 30 G6PD-deficient samples were used for the method's validation. Then, a total of 709 suspected G6PD-deficient samples collated from the Baise population were evaluated for G6PD status, type of mutation and effect of mutations. Results: The SNPscan test had a sensitivity of 100% [95% confidence interval (CI): 94.87%-100%] and a specificity of 100% (95% CI: 87.66%-100%) for identifying G6PD mutations. A total of fifteen mutations were identified from 76.72% (544/709) of the samples. The most common mutation was discovered to be G6PD Kaiping (24.12%), followed by G6PD Canton (17.91%), and G6PD Gaohe (11.28%). We compared the G6PD mutation spectrum among Zhuang, Han and other Southeast Asian populations, and the Zhuang population's mutation distribution was quite similar to that in the Han population. Conclusion: This study provided a detailed G6PD mutation spectrum in Baise of southwestern China and will be valuable for the diagnosis and research of G6PD deficiency in this area. Furthermore, the SNPscan assay could be used to quickly diagnose these G6PD mutations accurately.