葡萄糖-6-磷酸脱氢酶缺乏症患儿G-6-PDmRNA表达的研究

目的：检测葡萄糖-6-磷酸脱氢酶(G-6-PD)缺乏症患者及其家系成员的G-6-PDmRNA表达水平,从转录水平探讨其可能的发病机制。方法：提取G-6-PD缺乏症患者及其直系家属(患者父亲和/或母亲等)外周血RNA,采用逆转录方法形成cDNA后,运用逆转录实时定量PCR(QuantitativeReal-TimePCR,QRT-PCR)技术,测定G-6-PDmRNA的表达量。使用SPSS10.0统计分析软件将3组进行组间两两比较。结果：G-6-PD缺乏症患儿组mRNA表达量为0.57±0.19,父系组为0.74±0.21,母系组为0.67±0.21,患儿组与父系组比较t=-3.18,(P<0.01);与母系组比较t=-2.54,(P<0.05)。结论：G-6-PD缺乏症患者的G-6-PD基因发生突变后其G-6-PDmRNA表达量发生了改变,提示该病的发生与在转录水平上发生变化有关,在G-6-PD缺乏症的发病过程中起到一定的作用。     

运用PCR-DGGE技术检测葡萄糖-6-磷酸脱氢酶缺乏的初步研究

目的：运用多聚酶链反应-变性梯度凝胶电泳（PCR-DGGE）技术检测葡萄糖-6-磷酸脱氢酶（G-6-PD）缺乏患者及基因携带者基因变异,探讨其对该病的诊断和研究价值。方法：提取G-6-PD缺乏症患者及其家系（患者父亲和/或母亲等）的外周血RNA,逆转录合成cDNA后,选取第11至12外显子部分cDNA片段进行PCR-DGGE,观察其电泳行为,将电泳行为异常的标本进行基因测序,最后做出基因诊断。结果:：36个家系中33个家系发现G-6-PD基因在1304至1520片段出现PCR-DGGE多种异常电泳区带。9例母亲G-6-PD/6-PGD比值低于1.00,其中3例比值低于0.50,而且PCR-DGGE电泳行为一致,基因测序发现为双重杂合子;比值正常的G-6-PD缺乏基因携带者母亲均为单杂合子。该片段基因测序发现3个突变位点分别为：C1311T,G1376T,G1388A。各基因突变的位点有其特殊的电泳行为。结论：PCR-DGGE技术是一种敏感性高、可靠性强的筛查基因突变的方法。在临床研究G-6-PD缺乏,特别是常规诊断技术不能发现的女性G-6-PD缺乏基因携带者的检测中具有很强的应用价值。［中国当代儿科杂志,2007,9（6）：529-532］     

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.     

Salicylamide glucuronide formation in newborn babies with G-6-PD deficiency

Salicylamide glucuronide formation has been studied in 23 newborn babies with erythrocyte G-6-PD deficiency and in 15 normal newborns on the first day of life. Glucuronide formation was significantly lower (p less than 0.001) in the former in comparison with the controls. In the newborns with G-6-PD deficiency who subsequently became hyperbilirubinemic an even lower mean glucuronide formation was observed (p less than 0.01) in respect to the non-jaundiced G-6-PD-deficient newborns.     

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.     

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.     

广西恭城县瑶族和汉族居民G-6-PD缺乏症发病率及基因频率的调查

目的研究广西恭城县瑶族和汉族居民的G-6-PD缺乏症发病率及基因频率。方法使用G-6-PD试纸法初筛,四氮唑蓝定量法测定确认的方法调查对2050名(男1126,女1124)瑶族和874名(男481,女393)汉族初中学生进行G-6-PD缺乏症的调查。结果瑶族男缺乏率5·75%(显著缺乏4·87%,中度缺乏0·97%),瑶族女性缺乏率1.95%(显著0·59%,中度1·36%),瑶族男女合并总缺乏率为3·85%;瑶族男性基因频率为:0·057,瑶族女性杂合子的估计值为10·84%:汉族男性缺乏率7·06%(显著缺乏6·03%,中度缺乏1·04%),汉族女性缺乏率3·56%(显著0·76%,中度2·80%),汉族男女合并总缺乏率为5·49%;汉族男性基因频率为0·0706,汉族女性杂合子的估计值为13·12%;全县瑶族和汉族合并缺乏率为4·34%。结论恭城县G-6-PD缺乏发病率,瑶族比汉族的稍低,但民族间的差异比地域间的差异相对要小。     

不同G-6-PD活性新生儿光疗致溶血机制及其预防

目的探讨不同G6PD活性新生儿光疗溶血机制及预防。方法将G6PD正常与缺陷光疗患儿随机分为维生素E干预组和对照组,测定比较超氧化物歧化酶(SOD)、丙二醛(MDA)、活性氧(ROS)、总胆红素(TB)、血红蛋白(Hb)及光疗指数。结果光疗前G6PD缺陷组比正常组SOD和Hb低,ROS高;光疗中G6PD缺陷干预组比正常干预组SOD高,MDA低,光疗指数小,G6PD缺陷对照组比正常对照组ROS、MDA高,光疗指数大(各组比较均P<0.01或P<0.05)。光疗后G6PD缺陷对照组Hb下降,并比干预组低,G6PD正常两组Hb均下降,干预组比对照组高(各组比较均P<0.01或P<0.05)。结论光疗可致抗氧化能力下降,脂质过氧化损伤致G6PD缺陷光疗者溶血更突出,维生素E干预更有效。     

病毒性肝炎伴随G-6-PD缺乏率原因探讨

本院1992．1～1996．12儿童肝炎住院病例232例，均作出病原学诊断。G-6－PD检测用酶活性测定法，按陈顺存介绍的方法进行。≤1．2Iu／gHb为显著缺乏，1．3～3．2In／gHb为中间值，3．3～7．0IIJ／gHb为正常。232例肝炎患者，83例G－6－PD缺乏，G－6－PD缺乏率35.77％，男性缺乏率44．12％（75／170），女性缺乏率12．90％（8／62）．83例缺乏者中显缺67例，中间值16例，接受两次或两次以上检测者74例，占缺乏总数之89．16％（74／83）。本组对54例肝炎伴G－6－PD缺乏者作了家系调查，85．19％（46／54）符合伴性不显性遗传规律，结论：1．肝炎患者伴随G－6－PD缺乏率高，本组为35．77％。2．肝炎患者伴随G－6－PD缺乏绝大部分是原发性的，理由：G-6－PD缺乏病例中74例检测两次以上，占缺乏病例的89．16％（74／83），检测可靠性大，前后检查基本一致；49例在出院后6月～5年作了随诊，随诊的活性值与住院检查一致；本组89．16％（74／83）符合伴性不显性遗传规律。     

Neonatal screening for Glucose-6-Phosphate dehydrogenase deficiency

Objective : This study was carried out to detect the incidence of erythrocytic Glucose-6-Phosphate dehydrogenase (G-6-PD) deficiency, to compare the incidence of hyperbilirubinernia in G-6-PD deficient neonates as compared to G-6-PD normal neonates and to asses the usefulness of neonatal screening for G-6-PD deficiency.Method : In a retrospective hospital based study 2,479 male and female neonates consecutively born at Indraprastha Apollo hospital between July 1998 to June 2003 who were screened for G-6-PD levels were evaluated for the incidence of G-6-PD deficiency.Results : Incidence of G-6-PD deficiency was found to be 2.0%. Incidence in males was 283% and femle was 1.05%. The incidence of hyperbilirubinemia was found to be 32% in G-6-PD deficient neonates which was significantly higher than the incidence of hyperbilirubinemia in neonates with normal G-6-PD, which was 12.3% (P<0.001).Conclusion : Our data suggests that neonatal screening for G-6-PD deficiency is a useful test for preventing and early treatment of complications associated with it.     

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.     

(TA)n UGT 1A1 promoter polymorphism: a crucial factor in the pathophysiology of jaundice in G-6-PD deficient neonates

Increased heme catabolism has been reported in glucose-6-phosphate dehydrogenase (G-6-PD)-normal neonates who were also homozygous for (TA)7/(TA)7 (UGT1A1*28) uridine diphosphoglucuronate-glucuronosyltransferase 1A1 (UGT) promoter polymorphism (Gilbert syndrome). As G-6-PD deficiency is associated with increased hemolysis, we hypothesized that in G-6-PD-deficient neonates who also have the (TA)7/(TA)7 UGT promoter genotype, steady-state hemolysis would be even further increased. Male G-6-PD-deficient neonates were sampled for plasma total bilirubin (PTB), blood carboxyhemoglobin corrected for inhaled carbon monoxide in ambient air (COHbc) (an index of heme catabolism), and UGT (TA)n promoter genotype determination and compared with previously published G-6-PD-normal neonates. Although COHbc values were higher in the G-6-PD-deficient than in the G-6-PD-normal cohorts (0.97 +/- 0.32% of total Hb (tHb) versus 0.76 +/- 0.19% of tHb, p < 0.001), PTB values were similar (9.2 +/- 3.4 mg/dL versus 8.9 +/- 3.0 mg/dL, respectively, p = 0.3). Within the G-6-PD-deficient group, although COHbc values were alike between the three UGT promoter genotypes, PTB was higher in the (TA)7/(TA)7 homozygotes (11.1 +/- 4.0 mg/dL) compared with (TA)6/(TA)7 heterozygotes (9.1 +/- 3.2 mg/dL, p = 0.03) and wild-type (TA)6/(TA)6 homozygotes (8.8 +/- 3.4 mg/dL, p = 0.02). In the steady state, similar rates of hemolysis, but increased PTB in the G-6-PD- deficient, (TA)7/(TA)7 homozygotes, imply that (TA)7/(TA)7, homozygosity is central to increased PTB.     

血液学参数的变化与红细胞葡萄糖-6-磷酸脱氢酶活性关系的研究

本文报道１６４例住院的高胆红素血症患儿（贫血６６例，无贫血９８例）进行Ｇ－６－ＰＤ活性和几个血液学参数的测定，并作了相关性、回归分析和显著性检验。结果：Ｇ－６－ＰＤ活性与白细胞、网织红细胞、血小板数、血清钠及微量元素锌、硒含量呈正相关；与血红蛋白、红细胞和红细胞压积呈负相关，两者均有显著性意义（Ｐ＜０．０５～０．０１）。而与血清钾、氯、钙、白蛋白、球蛋白及胆红素含量无相关性。通过本实验结果分析，作者认为高胆红素血症患儿，伴有贫血或溶血时，由于骨髓增生，网织红细胞和年幼的红细胞数量增加，或者伴随感染时因白细胞明显增加等因素，致Ｇ－６－ＰＤ活性含量升高而掩盖了Ｇ－６－ＰＤ缺陷。因此，评价Ｇ－６－ＰＤ活性时，除了考虑以上几个血液学参数影响造成的误差，对贫血患儿的血样常规先行调整血浆和血细胞的比例外，白细胞增加者若能进行离心除去白细胞层后进行测定；或待感染控制后，有贫血者待贫血改善后；有溶血者待溶血停止后２—４个月左右，再复查Ｇ－６－ＰＤ活性，对Ｇ－６－ＰＤ缺陷才能作出正确的诊断。     

EFFECT OF OROTIC ACID UPON SERUM BILIRUBIN IN NEWBORN INFANTS WITH ERYTHROCYTE G-6-PD DEFICIENCY

Fifty mature male newborns with erythrocyte G-6-PD deficiency were used for a study con cerning the effectiveness of orotic acid in preventing severe hyperbilirubinemia. Twentyfive randomly selected neonates were given orotic acid (100 mg/kg/day) orally in two daily doses from their 1st to their 5th day of life. Twenty-five newborns were not treated According to these results orotic acid does not seem to be effective in preventing severe hyperbilirubinemia, which frequently occurs in newborn babies' with erythrocyte G-6-PD deficiency. and served as controls. Six exchange transfusions were performed in the test group and six in the controls.     

Acute haemolytic anaemia in typhoid fever

Summary Two G-6-PD deficient children with typhoid fever complicated by acute haemolytic anaemia are reported. One of them had the rare complication of haemoglobinuria. The role of typhoid infection versus chloramphenicol treatment in causing haemolysis in G-6-PD deficiency is discussed. From the Department of Pediatrics, Postgraduate Institute of Medical Education and Research, Chandigarh.     

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。     

Agar in control of hyperbilirubinemia of full-term newborn infants with erythrocyte G-6-PD deficiency.

40 full-term newborn infants with erythrocyte glucose-6-phosphate dehydrogenase (G-6-PD) deficiency were used for a study concerning the effectiveness of agar per os in preventing severe hyperbilirubinemia. 20 randomly selected neonates were given agar (1 g/kg/day) orally in 4 daily doses from their 1st to their 5th day of life. 20 infants were not treated and served as controls. Three exchange transfusions were performed in the experimental as well as in the control group. According to these results, agar does not seem to be effective in preventing severe hyperbilirubinemia, which frequently occurs in newborn infants with erythrocyte G-6-PD deficiency.     

Glucose-6-phosphate dehydrogenase,reduced glutathione and heinz bodies in congenital haemolytic anaemia

Summary Glucose-6-phosphate dehydrogenase (G-6-PD), glutathione instability (GSH) and heinz body formation were studied in ten children suffering from congenital haemolytic anaemia and in fifteen healthy subjects of similar age group. In congenital haemolytic anaemia, dye decolorisation time for assessing G-6-PD activity was within the normal range. Unstable GSH was less than 20% in four cases and more than 20% in the other four cases. In two cases no unstable GSH was observed. Heinz bodies, more than 50%, were present in nine of ten cases. Glutathione instability and increased percentage of heinz body formation with normal G-6-PD activity probably occurs due to glutathione reductase or TPNH (NADPH) deficiency. From the Department of Pathology and Microbiology, Sandar Patel Medical College, Bikaner, Rajasthan.     

Effect of vitamin K1 on glucose-6-phosphate dehydrogenase deficient neonatal erythrocytes in vitro

AIM: To determine whether vitamin K1, which is routinely administered to neonates, could act as an exogenous oxidising agent and be partly responsible for haemolysis in glucose-6-phosphat-dehydrogenase (G-6-PD). METHODS: G-6-PD deficient (n = 7) and control (n = 10) umbilical cord blood red blood cells were incubated in vitro with a vitamin K1 preparation (Konakion). Two concentrations of Vitamin K1 were used, both higher than that of expected serum concentrations, following routine injection of 1 mg vitamin K1. Concentrations of reduced glutathione (GSH) and methaemoglobin, indicators of oxidative red blood cell damage, were determined before and after incubation, and the mean percentage change from baseline calculated. RESULTS: Values (mean (SD)) for GSH, at baseline, and after incubation with vitamin K1 at concentrations of 44 and 444 microM, respectively, and percentage change from baseline (mean (SD)) were 1.97 + 0.31 mumol/g haemoglobin, 1.89 +/- 0.44 mumol/g (-4.3 +/- 13.1%), and 1.69 +/- 0.41 mumol/g (-14.5 +/- 9.3%) for the G-6-PD deficient red blood cells, and 2.27 +/- 0.31 mumol/g haemoglobin, 2.09 +/- 0.56 mumol/g (-7.2 +/- 23.2%), and 2.12 +/- 0.38 mumol/g (-6.0 + 14.1%) for the control cells. For methaemoglobin (percentage of total haemoglobin), the corresponding values were 2.01 +/- 0.53%, 1.93 +/- 0.37% (-0.6 +/- 17.4%) and 2.06 +/- 0.43% (5.7 +/- 14.2%) for the G-6-PD deficient red blood cells, and 1.56 +/- 0.74%, 1.70 +/- 0.78% (12.7 +/- 21.9%), and 1.78 +/- 0.71% (20.6 +/- 26.8%) for the control red blood cells. None of the corresponding percentage changes from baseline was significantly different when G-6-PD deficient and control red blood cells were compared. CONCLUSIONS: These findings suggest that G-6-PD deficient red blood cells are not at increased risk of oxidative damage from vitamin K1.     

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.