Neutropenia congénita de tipo IV: reporte de un caso / Congenital neutropenia type IV: case report

La neutropenia congénita grave (NCG) es una entidad heterogénea cuya característica común es un recuento absoluto de neutrófilos inferior a 0,5 x 10 9/l. Presenta gran heterogeneidad genética, las mutaciones más frecuentes son las del gen de la elastasa 2 (ELA 2). El tratamiento de primera elección es la administración de factor estimulador de colonias de granulocitos. Los pacientes con NCG presentan infecciones graves en etapas tempranas de la vida. Se presenta una paciente con NCG asociada a fenotipo peculiar con facies triangular, retromicrognatia, patrón venoso prominente en miembros inferiores, comunicación interauricular y mal progreso ponderal, en quien se diagnosticó déficit de la enzima glucosa 6 fosfato deshidrogenasa, subunidad catalítica 3 (G6PC3). A pesar de lo infrecuente de esta mutación como causa de NCG (2 %), su conocimiento cobra importancia porque la coexistencia del fenotipo característico con una NCG orienta en la solicitud del estudio genético que permite arribar al diagnóstico.

Severe congenital neutropenia (SCN) is a heterogeneous disease whose more common feature is an absolute neutrophil count less than 0.5 x 10 9/l. It presents great genetic heterogeneity. Autosomal dominant inherited mutations of the elastase 2 gene (ELA2) represent the most common etiology. The first choice treatment is the administration of granulocyte colony stimulating factor. Patients with SCN develop severe infections early in life. We present a patient who associated SCN to a peculiar phenotype, characterized by triangular facies, retromicrognathia, prominent venous pattern in the lower limbs, atrial septal defect and poor weight progress, in whom a deficiency of the enzyme glucose 6 phosphate dehydrogenase, a catalytic subunit 3 (G6PC3), was diagnosed. Despite the infrequency of this mutation as the origin of SCN (2%), its knowledge becomes important because the coexistence of the characteristic phenotype and SCN guides the request for the genetic study that allows reaching the diagnosis.

Retrospective analysis of a ten-year screening project for G6PD deficiency in neonates in Hainan Province / 中华检验医学杂志

Objective@#To investigate the prevalence of glucose-6-posphate dehydrogenase (G6PD) deficiency and its gene mutations among neonates in Hainan Province.@*Methods@#The G6PD activity of dried blood spots of 914 520 neonates born from 2007 to 2016 was screened by fluorescence spot test in Hainan Province. The G6PD/6-glucose phosphate dehydrogenase (6GPD) ratio method was used to confirm the diagnosis of suspected specimens, and 3 012 of year 2016 dried blood spots of neonates with G6PD deficiency were genotyped using the multicolor probe-based fluorescence melting curve analysis.@*Results@#From 2007 to 2016, 36 314 positive cases were screened in 914 520 neonates. A total of 26 370 cases of G6PD deficiency were diagnosed with an incidence rate of 2.88%(26 370/914 520) in Hainan Province. The incidences of G6PD deficiency were 2.80%(21 688/774 555) in ethnic Han population, 3.45% (4 292/124 419) in ethnic Li population, 3.31%(212/6 401) in ethnic Miao population and 1.95%(178/9 145) in other ethnic groups. There were significant differences in the incidence of G6PD deficiency in ethnic Han population and ethnic Li population(χ2=161.261, P=0.000), ethnic Miao population(χ2=6.104, P=0.013) and other ethnic groups(χ2=24.283, P=0.000). A total of 13 mutation types were detected by gene detection in 3 012 confirmed cases of G6PD deficiency, of which c.1376 G>T, c.1388 G>A, c.95 A>G and c.1024 C>T mutations and related combinations accounted for approximately 91.74%. Two mutations outside 16 genotypes, c.86 C>T and c.1311 C>T, were found by gene sequencing.@*Conclusions@#The incidence of G6PD deficiency among newborns in Hainan Province is high, and there are ethnic and regional differences. The dominant genetic mutations in Hainan Province are c.1376 G>T, c.1388 G>A, c.95 A>G and c.1024 C>T.

Prevalence of G6PD deficiency and molecular characterization of G202A, A376G and C563T polymorphisms in newborns in Southeastern Brazil / Prevalência da deficiência de G6PD e caracterização molecular dos polimorfismos G202A, A376G e C563T em neonatos no Sudeste do Brasil

ABSTRACT Objective To evaluate the prevalence of G6PD deficiency and characterize G202A, A376G and C563T polymorphisms in neonates using molecular assays. Methods A total of one thousand samples were tested through quantitative analysis of enzyme activity, detecting 25 G6PD-deficient individuals. Patients identified as deficient were submitted to molecular analysis quantitative real-time polymerase chain reaction - (qPCR) to investigate the presence of variants associated with the deficiency. Results The total prevalence of G6PD deficient was 2.5%. Of the 25 samples identified as deficient, 21 were submitted to qPCR assay to analyze the presence of G202A, A376G and C563T variants. All samples showed the G202A/A376G genotype, characterizing G6PD A- phenotype. Conclusion The prevalence of G6PD deficiency in the present study was similar to that observed in other study populations in Brazil. Molecular analysis identified in all patients the presence of the genetic polymorphism G202A/A376G, more common in the Brazilian population with G6PD deficiency, which is directly estimated by enzyme activity level.

RESUMO Objetivo Avaliar a prevalência da deficiência de G6PD e caracterizar, por ensaios moleculares, os polimorfismos G202A, A376G e C563T em recém-nascidos. Métodos Foram testadas mil amostras por meio da análise quantitativa da atividade enzimática, detectando 25 portadores de deficiência de G6PD. Os pacientes identificados como deficientes foram submetidos à análise molecular reação em cadeia da polimerase em tempo real (qPCR) para pesquisa da presença das variantes associadas à deficiência. Resultados A prevalência total de deficientes de G6PD foi de 2,5%. Das 25 amostras identificadas como deficientes, 21 foram submetidas ao qPCR, para análise da presença das variantes G202A, A376G e C563T. Todas as amostras apresentaram o genótipo G202A/A376G, caracterizando fenótipo G6PD A-. Conclusão A prevalência da deficiência da G6PD no presente estudo foi semelhante à verificada em outras populações de estudo no Brasil. A análise molecular identificou em todos os pacientes a presença do polimorfismo genético G202A/A376G, mais comum na população brasileira portadora da deficiência de G6PD, que é diretamente estimada pelo nível de atividade enzimática.

Phenotypic and genotypic spectra of patients with glucose-6-phosphate dehydrogenase deficiency gene known pathogenic variants: a single-center study / 中华儿科杂志

Objective@#To analyze the hotspots of known pathogenic disease-causing variants of glucose-6-phosphate dehydrogenase (G6PD) and the phenotype spectrum of neonatal patients with known pathogenic disease-causing variants of G6PD.@*Methods@#The known pathogenic disease-causing variants of G6PD were collected from Human Gene Mutation Database. Screening was performed for these variants among the 7 966 cases (2 357 neonatal, 5 609 non-neonatal) in the database of sequencing at Molecular Diagnosis Center, Children's Hospital of Fudan University. All these samples were from patients suspected with genetic disorder. The database contained Whole Exon Sequencing data and Clinical Exon Sequencing data. We screened out the patients with known pathogenic disease-causing variants of G6PD, analyzed the hotspot of G6PD and the phenotype spectrum of neonatal patients with known pathogenic disease-causing variants of G6PD.@*Results@#(1) Among the next generation sequencing data of the 7 966 samples, 86 samples (1.1%) were detected as positive for the known pathogenic disease-causing variants of G6PD (positive samples set). In the positive sample set, 51 patients (33 males, 18 females) were newborn babies. Forty-three patients (26 males, 17 females) had the enzyme activity data of G6PD. (2) Among the 86 samples, Arg463His, Arg459Leu, Leu342Phe, Val291Met were the leading 4 disease-causing variants found in 72 samples (84%). (3) Male neonatal patients with the same variants had the statistically significant differences in enzyme activity: among 13 patients with Arg463His, enzyme activity of 9 patients was ranked as grade Ⅲ, 1 case ranked as Ⅳ, 3 cases had no activity data;among 10 patients with Arg459Leu, enzyme activity of 4 patients was ranked as Ⅱ, 4 cases ranked as Ⅲ, 2 cases had no activity data;among 2 patients with His32Arg, enzyme activity of one patient was ranked as Ⅱ, another was Ⅲ. Male neonatal patients with the same mutation and enzyme activity also had the statistically significant differences in phenotype spectrum: among 9 patients with Arg463His and level Ⅲ enzyme activity, 6 presented hyperbilirubinemia, 2 met the criteria for exchange transfusion therapy, 2 showed hemolysis;among 4 patients with Arg459Leu and level Ⅱ enzyme activity, 3 presented hyperbilirubinemia;among 4 patients with Arg459Leu and level Ⅲ enzyme activity, 2 presented hyperbilirubinemia, 1 met the standard of exchange transfusion therapy;among 3 patients with Val291Met and level Ⅲ enzyme activity, 1 presented hyperbilirubinemia.@*Conclusions@#Arg463His, Arg459Leu, Leu342Phe, Val291Met were the hotspots variants for the G6PD. Patients with the same G6PD variants and sex present different phenotype, patients with the same G6PD variants, sex and enzyme activity also present different phenotype .

Neonatal indirect hyperbilirubinemia and glucose-6-phosphate dehydrogenase deficiency / 소아과

PURPOSE: This study aimed to determine the prevalence of glucose-6-phosphate dehydrogenase (G6PD) deficiency among infants with neonatal indirect hyperbilirubinemia (NIH); compare G6PD-deficient and G6PD-normal patients regarding hyperbilirubinemia and need for exchange transfusions (ET); and assess risk factors for ET and kernicterus. METHODS: This is a case-control retrospective study. Medical records of NIH patients admitted to the Pediatric Department, Salmaniya Medical Complex, Bahrain, between January 2007 and June 2010 were reviewed. Data on sex, age at presentation, hospitalization duration, need for ET, hemoglobin (Hb) level, reticulocyte count, direct Coombs test, serum total and indirect bilirubin levels, thyroid function, blood and urine cultures, G6PD status, and blood groups were collected and compared between the G6PD-deficent and G6PD-normal patients. RESULTS: Of 1,159 NIH patients admitted, 1,129 were included, of whom 646 (57%) were male. Among 1,046 patients tested, 442 (42%) were G6PD deficient, 49 (4%) needed ET, and 11 (1%) had suspected Kernicterus. The G6PD-deficient patients were mainly male (P<0.0001), and had lower Hb levels (P<0.0001) and higher maximum bilirubin levels (P=0.001). More G6PD-deficient patients needed ET (P<0.0001). G6PD deficiency (P=0.006), lower Hb level (P=0.002), lower hematocrit count (P=0.02), higher bilirubin level (P<0.0001), higher maximal bilirubin level (P<0.0001), and positive blood culture result (P<0.0001) were significant risk factors for ET. Maximal bilirubin level was a significant risk factor for kernicterus (P=0.021) and independently related to ET (P=0.03). CONCLUSION: G6PD deficiency is an important risk factor for severe NIH. In G6PD-deficent neonates, management of NIH should be hastened to avoid irreversible neurological complications.

Polimorfismo genético da glicose-6-fosfato desidrogenase na população da região de Araraquara, Estado de São Paulo / Genetic polymorphism of glucose-6-phosphate dehydrogenase in the population of Araraquara, State of São Paulo

The most important role played by the enzyme Glucose-6-Phosphate Dehydrogenase (G6PD) in erythrocyte metabolism is in generating energy and reducing power used to protect the cell against oxidative attack. G6PD deficiency is the erythroenzymopathy that most frequently causes hemolytic anemia, and more than 130 molecular variants have already been identified. The aim of this study was to analyze the genetic mutations in the G6PD-deficient adult males in the population of the region of Araraquara, São Paulo State. Out of 5087 male blood donors, 89 were deficient for G6PD, as confirmed by assaying the enzyme activity and electrophoresis on cellulose acetate. Thus, a frequency of 1.75% of G6PD-deficient patients was found, this value being similar to other investigations in São Paulo state. Molecular analysis was performed by amplification of genomic DNA with specific primers and digestion with restriction enzymes. In 96.6% of the patients, the G6PD A¯ variant was observed, with mutations at residues 376(A-G) and 202(G-A). Mean G6PD specific activity among the patients was 1.31 IU.g Hb-1.min-1 at 37ºC, that is 10.8% of the normal activity of the G6PD B enzyme. The variant forms G6PD A¯680(G-T) and 968(T-C) were not found. In 3.4% of the deficient individuals, the G6PD Mediterranean variant was found, with a mutation at 563(C-T). In these cases,mean enzymatic activity was 0.25 IU.g Hb-1.min-1 at 37ºC, or 2.1% of the enzymatic activity of G6PD B. Theuse of traditional techniques, allied to the identification of the different molecular variants, is important for the understanding of the structural and functional properties and hemolytic behavior of the red blood cells of the patient...

A importância da enzima Glicose-6-fosfato desidrogenase (G6PD) no metabolismo eritrocitário está na obtenção de energia calórica e redutora para a proteção celular contra agressões oxidativas. A deficiência de G6PD é a eritroenzimopatia que causa mais frequentemente anemia hemolítica, com mais de 130 variantes moleculares identificadas. O objetivo deste estudo foi realizar a análise molecular da deficiência de G6PD em uma população masculina adulta da região de Araraquara, SP, para a identificação das mutações genéticas. Nos 5087 doadores de sangue do sexo masculino pesquisados, foram encontrados 89 deficientes de G6PD, confirmados pela determinação da atividade enzimática e eletroforese em acetato de celulose, com frequência de 1,75%, valores semelhantes aos encontrados por outros pesquisadores no Estado de São Paulo. A análise molecular realizada pela amplificação do DNA genômico com iniciadores específicos e digestão com enzimas de restrição, demonstrou que 96,6% dos deficientes apresentaram a variante G6PD A¯, com as mutações 376(A-G) e 202(G-A) e atividade enzimática média de 1,31 UI.g de Hb-1.min-1 a 37ºC, correspondendo a 10,8% da atividade enzimática da enzima normal G6PD B. Não foram encontradas as formas variantes G6PD A¯ 680(G-T) e 968(T-C). Em 3,4% dos indivíduos deficientes, foi encontrada a variante G6PD Mediterrânea, mutação 563(C-T) e atividade enzimática média de 0,25 UI.g de Hb-1.min-1 a 37ºC, correspondendo a 2,1% da atividade enzimática da G6PD B. A utilização das técnicas tradicionais, aliadas à identificação da variante molecular, são importantes na compreensão das propriedades estruturais, funcionais e comportamento hemolítico dos glóbulos vermelhos do paciente...

Analysis of blood group serology results in 276 cases of neonatal jaundice / 国际检验医学杂志

Objective To understand the incidence of hemolytic disease in newborn (HDN)among the newborns with jaundice and the coincidence degree of the blood group serological results and the clinical diagnosis in HDN.Methods The microcolumn gel method was adopted to detect the 3 serological indexes in 276 jaundice newborns of maternal fetal blood group incompatibility,in-cluding the direct antiglobulin test,free antibody test and antibody release test.Results 108 cases of HDN were clinically diagnosed with the positive rate of 39.13%.The positive detection rate in newborns with 0-2 d old was highest(50.00%).Conclusion The serological test can provide the basis for the early diagnosis and treatment of HDN.Collecting the specimen as early as possible can improve the positive diagnosis rate of HDN.

Neonatal jaundice and glucose-6-phosphate dehydrogenase / Icterícia neonatal e deficiência de glicose-6-fosfato desidrogenase

A deficiência de glicose-6-fosfato desidrogenase em neonatos pode ser a responsável pela icterícia neonatal. Este comentário científico é decorrente do relato sobre o tema publicado neste fascículo e que preocupa diversos autores de outros países em relação às complicações em neonatos de hiperbilirrubinemia, existindo inclusive proposições de alguns autores em incluir o teste para identificar a deficiência de glicose-6-fosfato desidrogenase nos recém-nascidos.

Glucose-6-phosphate dehydrogenase in newborn babies may be responsible for neonatal jaundice. There is a concern of many authors from other countries in respect to complications in neonates with hyperbilirubinemia; some authors even propose screening for glucose-6-phosphate dehydrogenase deficiency in newborn babies. A scientific report on this subject is published in this issue.

Prevalência da deficiência da glicose-6-fosfato desidrogenase em doadores de sangue de Mossoró, Rio Grande do Norte / Prevalence of glucose-6-phosphate dehydrogenase deficiency in blood donors of Mossoró, Rio Grande do Norte

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common human enzymopathy. It affects as many as 330 million individuals worldwide. This deficiency may determine neonatal jaundice, chronic nonspherocytic hemolytic anemia and acute hemolytic anemia induced by drugs, infections and broad bean ingestion. The efficacy of blood transfusion is decreased when the donor is G6PD deficient. In this study, we aimed at determining the prevalence of G6PD deficiency in blood donors of Mossoro, Brazil. Samples of 714 blood donors (576 men and 138 women; 343 white and 371 non-white) with ages ranging from 18 to 62 years and that accepted to participate in the study were analyzed. All participants answered a standard questionnaire. G6PD activity was analyzed by the methemoglobin reduction test with deficiency being confirmed by the semiquantitative test. The overall prevalence of G6PD deficiency in blood donors was 3.8 percent, similar to the rate described for others regions of Brazil. There was no significant statistical difference in the frequency of G6PD deficiency between men and women, nor between white and non-white blood donors. This relatively high frequency of G6PD deficiency highlights a need to screen blood donors for this condition.

A study on the influential factors of G6PD/6PGD specific value assay in the heterozygotes of G6PD gene variants in female patients / 国际检验医学杂志

Objective To improve the detection of G6PD heterozygotes in female patients by the optimum experimental factors of G6PD/6PGD specific value assay.Methods (1)Identifying the mutations of G6PD gene with the use of amplified refractory mutation system (ARMS).(2)Measuring the G6PD/6PGD specific value.Results According to the data analysed by statistics and ROC curve, the optimum experimental factors included that the incubation temperature was 37℃,the substrate concentrations were 0.78 mmol/L G6PNa2 and 0.195mmol/L NADP+, the reaction time was 10min.Conclusion The optimum experimental factors of G6PD/6PGD specific value assay may be used to improve the detection rate of G6PD heterozygotes in female patients.

Application and clinical value of screening with umbilical blood on the disease of glucose-6-phosphate dehydrogenate deficiency / 中国医师杂志

Objective To investigate the incidence and diagnosis of glucose-6-phosphate dehydrogenate(G-6-PD) deficiency through screening with umbilical blood or infants' peripheral blood.Methods The umbilical blood of 11574 infants delivered in our hospital was detected to screen G-6-PD deficiency.Activity of G-6-PD was also detected in 320 G-6-PD deficiency infants and 215 normal infants from 3 to 5 years old.Results Six hundred and forty-one patients in 11574 cases were screened with umbilical blood as G-6-PD deficiency and the incidence rate was 5.5%.The incidence rates in boys and girls were 7.9% and 3.0% respectively with significant difference(P

Analysis on screening of cord blood specimens for G-6-PD deficiency / 中华围产医学杂志

Objective To explore the incidence of G-6-PD deficiency in Dongguan District,Dongguan,Guangdong province. Methods Cord blood was obtained in 9676 cases of live births. G6PD/6PGD ratio was measured. Results Two hundred and sixty-five cases were diagnosed as G-6-PD deficiency giving an incidence of 2.74%. The incidence in male (4.07%,230/5646) was significantly higher than that in female (0.875,35/4030) ( P

Study on Na~+-K~+ ATPase and Ca~(2+) -Mg~(2+) ATPase activities of human erythrocyte membrane in G6PD deficient individuals / 中国病理生理杂志

By using Person's separating blood ghost method basically, Na~+-K~+ ATP ase and Ca~(2+)-Mg~(2+) ATPase activties of human erythrocyte membrane were studied. The comparison was made between 11 G6PD deficient subjects and 11 healthy control persons. The results showed that both enzyme activities as well as ouabain inhibition rate were decreased in G6PD deficient individuals (P