遗传因素在广西新生儿高胆红素血症中的作用

目的探讨UGT1A1 G71R突变、OATP2A388G突变和G-6-PD缺乏对在广西新生儿高胆红素血症发病的作用。方法用四氮唑蓝定量法（NBT法）测定G-6-PD酶活性。聚合酶链反应-等位基因特异性寡核苷酸探针点杂交（PCR-ASO）法确定G71R基因型。限制性片段长度多态性分析（RFLP）检测A388G基因型。测定109例新生儿脐血的G-6-PD活性及G71R基因型,其中101例同时检测了A388G基因型。据G-6-PD活性及G71R或A388G基因型分组,分析UGT1A1G71R突变、OATP2A388G突变和G-6-PD缺乏与足月新生儿高胆红素血症之间关系。结果G71R等位基因频率在G-6-PD缺乏组为22．03％,在G-6-PD正常组为28．00％。G-6-PD缺乏共存有G71R突变纯合子或杂合子的新生儿高胆红素血症发生率（95．50％）高于G-6-PD正常且G71R为野生型的新生儿（53．90％）,x^2=10．45,P=0．0012,前者发生高胆红素血症的机会比（95％可信区间）[OR（95％CI）]为18．00（2．12,152．9）。A388G等位基因频率在G-6-PD缺乏组为20．O％,在G-6-PD正常组为18．5％。G-6-PD缺乏共存有A388G突变新生儿的高胆红素血症发生率（90．0％）高于G-6-PD正常且A388G为野生型的新生）L（44．80％）,X2=10．39,P=0．0013,前者发生高胆红素血症的伽（95％CT）为11．08（2．15,56．48）。结论G71R突变与G-6-PD缺乏共存或A388G突变与G-6-PD缺乏共存对广西足月新生儿高胆红素血症的发生有协同作用。     

Neonatal hyperbilirubinemia in African American males: the importance of glucose-6-phosphate dehydrogenase deficiency

OBJECTIVE: To perform risk factor analysis for the prediction of hyperbilirubinemia in an African American male neonatal cohort. STUDY DESIGN: A database of 500 previously published term and near-term African American male neonates was further analyzed to determine the role of risk factors for hyperbilirubinemia. Factors studied included birth weight >/=4.0 kg, gestational age /=75(th) percentile. Hyperbilirubinemia was defined as any bilirubin value >/=95(th) percentile on the hour-of-life-specific bilirubin nomogram. RESULTS: Forty-three (8.6%) neonates developed hyperbilirubinemia. At 48 +/- 12 hours, median transcutaneous bilirubin was 8.3 mg/dL, 75(th) percentile 10.0 mg/dL, and 95(th) percentile 12.6 mg/dL. Of the risk factors, only exclusive breast-feeding, G-6-PD deficiency and predischarge bilirubin >/=75(th) percentile were significant (Adjusted Odds Ratios [95% Confidence Intervals; CI] 3.15 [1.39-7.14], P = .006; 4.96 [2.28-10.80], P = .001; and 7.47 [3.50-15.94], P < .0001, respectively). G-6-PD-deficient neonates who were also premature and breast-feeding had the highest incidence of hyperbilirubinemia (60%). CONCLUSIONS: African American male neonates may be at higher risk for hyperbilirubinemia than previously thought. Screening for G-6-PD deficiency and predischarge bilirubin determination may be useful adjuncts in hyperbilirubinemia prediction in these newborns.     

(TA)n UDP-glucuronosyltransferase 1A1 promoter polymorphism in Nigerian neonates

Nigerian neonates have a high incidence of bilirubin encephalopathy. Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is prevalent in this population. (TA)7 promoter polymorphism in the gene encoding the bilirubin conjugating enzyme UDP-glucuronosyltransferase 1A1 (UGT1A1) potentiates hyperbilirubinemia in G-6-PD deficient neonates. We studied (TA)n allele frequency to determine, at least in part, its contribution to the frequency and severity of hyperbilirubinemia. DNA was extracted from umbilical cord blood of sequentially born Nigerian neonates and the (TA)n UGT1A1 promoter sequence determined. The (TA)n allele distribution was compared with reported adults of varying African ancestry and Sephardic Jewish neonates. Among 88 Nigerian neonates, (TA)6 and (TA)7 alleles were almost equally distributed (0.46 and 0.43, respectively). Some individuals with (TA)5 and (TA)8 sequences were encountered. Allele distribution was similar to that of the African ancestry population but differed from the Sephardic Jewish newborns, in whom the (TA)6/(TA)7 distribution was 0.65/0.35. Whereas 45% of Nigerian alleles and 50% of African ancestry alleles, respectively, included a (TA)7 or (TA)8 sequence, only 35% of Jewish alleles were (TA)7 (p < 0.001), and no (TA)8 alleles were encountered. The high frequency of (TA)n promoter polymorphism, coupled with G-6-PD deficiency, may contribute to the pathogenesis of extreme neonatal hyperbilirubinemia in Nigeria.     

Glucose-6-phosphate dehydrogenase deficiency and kernicterus of South-East anatolia

OBJECTIVE: We aimed to investigate the rate of kernicterus, and physical and laboratory examination findings in hyperbilirubinemic infants with glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. MATERIALS AND METHODS: This study was carried out in the Dicle University Hospital Neonatal Intensive Care Unit between June 2005 and June 2006. Out of 56 male neonates who needed an exchange transfusion due to hyperbilirubinemia, 10 with G-6-PD deficiency were included in the study. Maternal age, gestational age, route of delivery, birth weight, age at the time of admission, and treatment and outcome were recorded. Laboratory investigations included determination of direct and indirect serum bilirubin concentrations, blood group typing, direct Coomb test, complete blood count, blood smear, thyroid-stimulating hormone, T4, C-reactive protein, urine analysis, and G-6-PD level. RESULTS: Out of 56 male neonates requiring exchange transfusion, 10 had G-6-PD deficiency (18%). In G-6-PD deficient neonates, other factors known to cause hyperbilirubinemia were excluded. The mean gestational age and the mean maternal age was 38.2+/-1.0 weeks and 31.3+/-5.9 years, respectively. The mean bilirubin level was 42.1+/-13.7 mg/dL. Four patients required a second exchange transfusions, and only 1 transfusion was sufficient for the remaining patients. Five patients (55%) developed kernicterus. CONCLUSIONS: Early detection of G-6-PD deficiency in the affected newborns may be important for reducing the risk of severe hyperbilirubinemia, kernicterus, and the need for exchange transfusion.     

Glucose-6-phosphate dehydrogenase deficiency in neonates

Objective: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an inherited deficiency that may be the cause of neonatal hyperbilirubinemia, as has been found in several countries and among widely different ethnic groups, especially in Mediterranean region. Our aim was to study the prevalence of G6PD deficiency in relation to neonatal jaundice.Methods : From March 1998 to April 2001 we studied 705 clinically icteric neonates who were admitted to Al-Zahra and Beheshti hospitals, two teaching hospitals in Isfahan, Iran. Laboratory investigations included determination of direct and indirect serum bilirubin concentrations, blood group typing, direct coomb’s test, hemoglobin, blood smear, reticulocyte count and G6PD level.Results: In only 53(7.5%) of cases G6PD deficiency was diagnosed. In all G6PD deficient neonates no evidence of other factors known to cause hyperbilirubinemia were detected. The sex distribution was 13(24.5%)females and 40(75.5%)males in the G6PD deficient group. The mean bilirubin level in G6PD deficient and G6PD normal groups were 22.26 +/-8.36 and 18.14 +/-3.85 mg/dl, respectively (p=0.001). Phototherapy was required in G6PD deficient and other icteric neonates with duration of 3.76 +/-1.93 and 3.13 +/-2.14 days, respectively (p=0.045). Twenty-seven of the 53(50.9%) G6PD deficient infants required exchange transfusion. None of them developed kernicterus.Conclusions: Since the prevalence of severe hyperbilirubinemia among our neonates was relatively high and about half of them required exchange transfusion, early detection of this enzymopathy regardless of sex and close surveillance of the affected newborns may be important in reducing the risk of severe hyperbilirubinemia and exchange transfusion.     

Cord plasma alpha-fetoprotein values and neonatal jaundice

Umbilical cord plasma alpha-fetoprotein (AFP) values were determined in 127 infants with hyperbilirubinemia (56 glucose-6-phosphate dehydrogenase (G-6-PD) deficient and 71 G-6-PD normal) and 136 control subjects (73 G-6-PD deficient and 63 G-6-PD normal). The mean alpha-fetoprotein value of 173 +/- 35.2 (SD) mg/L for the group of infants with hyperbilirubinemia was significantly greater than that (122 +/- 21.7 mg/L) for the control infants (P less than .001). G-6-PD status and sex did not significantly affect the alpha-fetoprotein values. Using an alpha-fetoprotein level of 130 mg/L as a "cut-off" value, the incidence of false-positive results was 25.5% and the incidence of false-negative results was 11.8%. This test can be used as a screening procedure to detect infants at high risk for hyperbilirubinemia.     

Neonatal hyperbilirubinemia associated with glucose-6-phosphate dehydrogenase deficiency in Sephardic-Jewish neonates: incidence, severity, and the effect of phototherapy.

Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is frequently associated with neonatal hyperbilirubinemia, and sometimes kernicterus, often in the absence of any identifiable trigger or hematological evidence of hemolysis. The aim of this study was to compare the incidence and severity of, and the effect of phototherapy on, jaundice in G 6-PD-deficient vs G-6-PD-normal neonates in the Sephardic-Jewish community. Healthy term newborns, born to mothers of families stemming from geographic areas known to be "at risk" for G-6-PD deficiency, were screened for the condition and surveyed for hyperbilirubinemia. Seventy-five G-6-PD-deficient neonates formed the study group, while 266 neonates with normal levels of the enzyme formed the control group. Neonates with any other identifiable cause for jaundice were excluded. Phototherapy was commenced when the serum bilirubin levels reached 16 mg/dL (274 mumol/L) or more, and it was discontinued at 12 mg/dL (205 mumol/L) or less. Hyperbilirubinemia developed in 27 (36%) of the deficient neonates (serum total bilirubin greater than 13.9 mg/dL [238 mumol/L]), compared with 50 (18.8%) of control neonates (P = .002), while 20 (26.7%) of the study group required phototherapy, compared with 31 (11.7%) of control neonates (P = .002). Two neonates in the study group required exchange transfusion (serum bilirubin greater than 20 mg/dL [342 mumol/L]), vs 0 in the control group (not significant).(ABSTRACT TRUNCATED AT 250 WORDS)     

Combination of ABO blood group incompatibility and glucose-6-phosphate dehydrogenase deficiency: effect on hemolysis and neonatal hyperbilirubinemia

The incidence (%) of hyperbilirubinemia (serum bilirubin ≥257 μmol/l) was similar in neonates with a combination of ABO incompatibility and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency (45%), with ABO incompatibility (54%) or G-6-PD deficiency (37%), alone (ns). Carboxyhemoglobin values, corrected for inspired CO, were similarly elevated in all three groups (0.87 ± 0.32%, 0.82 ± 0.29%, 0.76 ± 0.18%, respectively, ns), but correlated with bilirubin only in those with ABO incompatibility alone. ABO-incompatible/G-6-PD-deficient neonates, compared with those with either condition alone, are not at increased risk for hemolysis or hyperbilirubinemia.     

β-Thalassemia trait and hyperbilirubinemia in G-6-PD deficient newborn infants

Hb A₂ was determined in 50 subjects with erythrocyte G-6-PD deficiency who presented with hyperbilirubinemia in the neonatal period and in 100 non-hyperbilirubinemic G-6-PD deficient newborn infants, at the age of 12 months or more. Six subjects in the first group and 13 in the second were found to be carriers of the -thalassemia trait. Statistical analysis of the data did not show any significant difference between the two groups. It seems that the -thalassemia trait does not provide any protection against neonatal hyperbilirubinemia associated with G-6-PD deficiency.     

G-6-PD缺陷与新生儿高胆、婴幼儿贫血及婴儿肝炎综合征关系的调查

广西是我国Ｇ－６－ＰＤ缺陷高发区。Ｇ－６－ＰＤ缺陷发病的主要表现为急慢性溶血性贫血和由此而产生的高间胆红素血症及胆汁郁积。近十年我院门诊及病房４４０例患儿：２３７例新生儿高间胆包括核黄症后遗症患儿。Ｇ－６－ＰＤ缺陷检出率达６９．６％，其中显著缺陷４３．９％（１０４／２３７），中间值２５．７％（６１／２３７）；１０３例３个月以下的婴儿贫血原因待查患儿，Ｇ－６－ＰＤ缺陷检出率达５９．２２％（３６／１０３）；１００例婴儿肝炎综合征患儿，Ｇ－６－ＰＤ缺陷检出率达１８％（１８／１００）。Ｇ－６－ＰＤ缺陷男女经例为２．３７：１。６７例进行家系调查，２８例Ｇ－６－ＰＤ缺陷男婴，母亲检出率为６７．８％（１８／２８）；１４例Ｇ－６－ＰＤ缺陷女婴，父亲检出率４３％（６／１４），母亲检出率５０％（７／１４）。说明了在我区Ｇ－６－ＰＤ缺陷是引起新生儿高间胆以及核黄痊后遗症、婴幼儿贫血较常见而且重要原因之一。     

THE RISK OF JAUNDICE IN GLUCOSE-6-PHOSPHATE DEHYDROGENASE DEFICIENT BABIES EXPOSED TO MENTHOL

Abstract. Olowe, S. A. and Ransome-Kuti, O. (Department of Paediatrics, College of Medicine of the University of Lagos, Lagos, Nigeria). The risk of jaundice in glucose-6-phosphate dehydrogenase babies exposed to menthol. Acta Paediatr Scand, 69:341, 1980.—A major cause of neonatal morbidity and mortality in Lagos, Nigeria, is severe neonatal jaundice seen in G-6-PD deficient babies. The observation that the jaundice is more severe in outpatient than in inpatient babies suggests that its cause is exogenous. "Mentholated" powder which is commonly used in many clinics and at home to dress umbilical cords was suspected to be the offending agent. A controlled study of the effects of one of these powders was carried out on 60 consecutive G-6-PD deficient babies. In 30 of them the umbilical cords were dressed daily with the powder while the remaining half who were untreated served as controls. The treated babies developed statistically more significant jaundice than the controls. Inability of neonates to conjugate menthol in this power is probably responsible for the jaundice developed by these G-6-PD deficient babies. It is concluded that the use of menthol and/or camphor-containing commercial products on neonates be discontinued, especially in communities where the incidence of G-6-PD deficiency is high as the use of such products may be contributing to the severity of neonatal jaundice.     

Cord blood G-6-PD activity by quantitative enzyme assay and fluorescent spot test in Chinese neonates

Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is a common X-linked recessive disorder among the Chinese population. Neonatal screening for this condition is important and with necessary precaution, enzyme deficient infants are less likely to develop severe haemolysis and subsequent kernicterus. Screening of G-6-PD deficiency by fluorescent spot test on cord blood samples of 1228 Chinese neonates revealed an incidence of 4.4% in males and 0.35% in females. Simultaneous direct enzyme assay confirmed the sensitivity and specificity of the spot test in the identification of male hemizygotes and female homozygotes. However, the spot test was unsatisfactory in detecting heterozygotes. Even quantitative enzyme assay could detect only 70% of the partially deficient subjects.     

Genetic polymorphisms in Thai neonates with hyperbilirubinemia

Aim:  Polymorphisms of the UGT1A1 gene, SLCO1B1 gene and GST gene have been associated with significant hyperbilirubinemia. We would like to determine whether the variation of UGT1A1 gene, SLCO1B1 gene and GST gene may play a significant role in neonatal hyperbilirubinemia in Thai infants.
Methods:  Ninety-one study subjects (hyperbilirubinemic group) and 86 control subjects were studied.
Results:  The cause of neonatal hyperbilirubinemia could not be identified in 64 infants (70.3%), ABO blood group incompatibility in 14.3% and Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency in 8.8%. In the hyperbilirubinemic group, 23 of 91 (25.3%) infants demonstrated variant of UGT1A1 at nucleotides (nt) 211 as compared to 6 of 86 (7%) in the control group (p = 0.001). There were no significant differences between groups in the variants UGT1A1 at nt 686, SLCO1B1 gene at nt 388, 463 and the GST gene. Male infants with G-6-PD deficiency were associated with hyperbilirubinemia (21.2% vs. 4.8% in the control group) with an odds ratio (OR) of 5.37 (p =0.02). The relationship between G-6-PD and variant in UGT1A1 gene at nt 211 could not be determined.
Conclusion:  Thai infants with variant in the UGT1A1 at nt 211 or with G-6-PD deficiency are at higher risk for developing neonatal hyperbilirubinemia.     

Cord blood G-6-PD activity by quantitative enzyme assay and fluorescent spot test in Chinese neonates

Glucose-6-phosphate dehydrogenase (G-6-PD) deficiency is a common X-linked recessive disorder among the Chinese population. Neonatal screening for this condition is important and with necessary precaution, enzyme deficient infants are less likely to develop severe haemolysis and subsequent kernicterus. Screening of G-6-PD deficiency by fluorescent spot test on cord blood samples of 1228 Chinese neonates revealed an incidence of 4.4% in males and 0.35% in females. Simultaneous direct enzyme assay confirmed the sensitivity and specificity of the spot test in the identification of male hemizygotes and female homozygotes. However, the spot test was unsatisfactory in detecting heterozygotes. Even quantitative enzyme assay could detect only 70% of the partially deficient subjects.     

Erythrocyte glucose-6-phosphate dehydrogenase status of newborns and adults in eastern Libya

One hundred and twenty cord and 320 venous blood samples were collected from Libyan newborns and adults respectively for the estimation of glucose-6-phosphate dehydrogenase (G-6-PD) activity by a screening technique and by quantitative estimation. The mean (S.D.) enzyme activity in the non-deficient neonates and adults was 1.13 (0.23) and 0.87 (0.21) IU/ml RBC/min respectively. The incidence of G-6-PD deficiency in the male population was 2.8%. The enzyme activity in the deficient male population ranged from 0-19.5%; none of them was symptomatic or had haematological abnormality. Of the female subjects 1.8% had enzyme activity of 50-65%. The frequency of enzyme deficiency appears to be low compared with that found in other Arab populations and is comparable with the incidence in other mediterranean countries.     

新生儿高胆红素血症再入院的现状和危险因素分析

目的 探讨新生儿高胆红素血症再入院情况及相关危险因素。方法 选择2017年1月至2019年12月新生儿高胆红素血症再入院患儿85例作为研究组,按1：2比例在同期新生儿高胆红素血症未再入院病例中配对随机选取170例作为对照组,分析比较两组患儿的临床资料及再入院的危险因素。结果 研究期间新生儿高胆红素血症再入院率为2.30%,中位再入院间隔天数为5 d。研究组首次出院时总胆红素和间接胆红素水平明显高于对照组（P < 0.05）;首次住院期间蓝光治疗时间长于对照组（P < 0.05）。研究组出生体重、胎龄、首次入院时年龄均低于对照组（P < 0.05）,研究组合并葡萄糖-6-磷酸脱氢酶（G-6-PD）缺乏症比例和合并溶血病比例高于对照组（P < 0.05）。多因素logsitic分析显示,胎龄小、首次入院时年龄小、合并G-6-PD缺乏症是新生儿高胆红素血症再入院的危险因素（分别OR=1.792、1.415、2.829,P < 0.05）。结论 对存在胎龄小、首次入院时年龄小、合并G-6-PD缺乏症等高危因素的高胆红素血症新生儿,应加强住院及出院后管理,防止该病再入院的发生。     

广西南宁地区G6PD基因突变与新生儿黄疸的关系

目的：分析本地区最常见的三种基因突变型G1388A、G1376T和A95G与葡萄糖-6-磷酸脱氢酶（G-6-PD）活性之间的相关性,并探讨G-6-PD基因突变对新生儿黄疸的影响。方法：124例广西南宁的高胆红素血症新生儿为研究对象。应用突变特异性扩增系统法检测G-6-PD基因突变,应用硝基四氮唑蓝（NBT）定量法检测G-6-PD活性。比较G-6-PD不同基因突变型之间以及与正常组之间胆红素脑病发生率、出生72 h后血清胆红素峰值组间的差异。采用非条件logistic回归分析血清胆红素值>340 μmol/L的危险度。结果：124例中有37例G-6-PD 基因突变（G1388A 20例,G1376T 14例,A95G 4例,1例同时存在G1388A与A95G突变）。20例G1388A突变者中5例（25%）G-6-PD酶活性正常,14例G1376T突变者中4例（29%）G-6-PD酶活性正常,4例A95G突变者G-6-PD 酶活性均缺乏。G1388A与G1376T组胆红素脑病发生率及出生72 h后血清胆红素峰值差异无显著性。G-6-PD 突变组出生72 h后血清胆红素峰值、胆红素脑病发生率及血清胆红素>340 μmol/L的危险度与G-6-PD正常组相比,差异无显著性。结论：广西南宁地区G-6-PD突变仍常见G1388A、G1376T和A95G基因型。NBT法诊断G-6-PD缺乏存在假阴性。不同基因型对出生72 h后血清胆红素峰值、胆红素脑病发生率的影响无差异。单独的G-6-PD基因突变对生后72 h血清胆红素峰值、急性胆红素脑病发生率及血清胆红素大于340 μmol/L危险性均无影响。［中国当代儿科杂志,2009,11（12）：970-972］     

新生儿高胆红素血症再入院的现状和危险因素分析

目的 探讨新生儿高胆红素血症再入院情况及相关危险因素。方法 选择2017年1月至2019年12月新生儿高胆红素血症再入院患儿85例作为研究组,按1：2比例在同期新生儿高胆红素血症未再入院病例中配对随机选取170例作为对照组,分析比较两组患儿的临床资料及再入院的危险因素。结果 研究期间新生儿高胆红素血症再入院率为2.30%,中位再入院间隔天数为5 d。研究组首次出院时总胆红素和间接胆红素水平明显高于对照组（P < 0.05）;首次住院期间蓝光治疗时间长于对照组（P < 0.05）。研究组出生体重、胎龄、首次入院时年龄均低于对照组（P < 0.05）,研究组合并葡萄糖-6-磷酸脱氢酶（G-6-PD）缺乏症比例和合并溶血病比例高于对照组（P < 0.05）。多因素logsitic分析显示,胎龄小、首次入院时年龄小、合并G-6-PD缺乏症是新生儿高胆红素血症再入院的危险因素（分别OR=1.792、1.415、2.829,P < 0.05）。结论 对存在胎龄小、首次入院时年龄小、合并G-6-PD缺乏症等高危因素的高胆红素血症新生儿,应加强住院及出院后管理,防止该病再入院的发生。     

Relationship between Exposure to Icterogenic Agents, Glucose-6-Phosphate Dehydrogenase Deficiency and Neonatal Jaundice in Nigeria

ABSTRACT. In a study of the relationship between exposure to icterogenic agents, G-6-PD deficiency and severe neonatal jaundice (NNJ) (serum bilirubin 3±205 umol/I) in 234 Nigerian term male neonates, 106 infants with severe NNJ and 128 controls, it was found that 62.3 % of the jaundiced infants and 13.3 % of the infants without NNJ were G6PD deficient (p<0.01). The proportion of infants exposed to icterogenic agents in the two groups was very similar (p<0.5). There was a strong association between exposure to icterogenic agents and NNJ in 83 G6PD deficient infants (p<0.01), but there was no association between exposure to icterogenic agents and NNJ in the whole group of 234 infants or in 151 infants with normal G6PD status. It is concluded that there is an association between genetically determined G-6-PD deficiency and exogenous agents in causing severe NNJ in Nigerian infants.     

GLUCOSE-6-PHOSPHATE DEHYDROGENASE AND RED CELL PYRUVATE KINASE DEFICIENCY IN NEONATAL JAUNDICE CASES IN EGYPT

Glucose-6-phosphate dehydrogenase (G6PD) deficiency can lead to acute hemolytic anemia, chronic nonspherocytic hemolytic anemia, and neonatal jaundice. Neonatal red cell pyruvate kinase (PK) deficiency may cause clinical patterns, ranging from extremely severe hemolytic anemia to moderate jaundice. The authors aimed at studying the prevalence of G6PD and PK deficiency among Egyptian neonates with pathological indirect hyperbilirubinemia in Cairo. This case-series study included 69 newborns with unconjugated hyperbilirubinemia. All were subjected to clinical history, laboratory investigations, e.g., complete blood counts, reticulocytic counts, direct and indirect serum bilirubin levels, Coombs tests, qualitative assay of G6PD activity by methemoglobin reduction test, and measurement of erythrocytic PK levels. The study detected 10 neonates with G6PD deficiency, which means that the prevalence of G6PD deficiency among Egyptian neonates with hyperbilirubinemia is 14.4% (21.2% of males). G6PD deficiency was significantly higher in males than females (P = .01). The authors detected 2 cases with PK deficiency, making the prevalence of its deficiency 2.8%. These data demonstrate that G6PD deficiency is an important cause for neonatal jaundice in Egyptians. Neonatal screening for its deficiency is recommended. PK deficiency is not a common cause of neonatal jaundice. However, this needs further investigation on a larger scale.