Methemoglobin Reduction Test Research Articles

A positive correlation between mutated gene of sickle cell anemia and glucose-6-phosphate dehydrogenase among gond tribes of Chhattisgarh, India

BackgroundGlucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymopathy affecting millions of individuals worldwide. It is believed that the prevalence of G6PD deficiency in different ethnic populations increases its association with other pathological conditions especially sickle cell anemia (SCA), as they both are well-known adaptations against malaria. Thus, the present study aims to determine the frequency of G6PD deficiency among SCA patients and the association between them in the tribal community (Gond) of Chhattisgarh, India. MethodA total of 810 samples from three different age groups i.e., 10–20, 21–30, and 31–40 years were collected from the tribal community (Gond) of Kabirdham district of Chhattisgarh. The frequency of SCA was determined by a slide test followed by cellulose acetate paper electrophoresis and G6PD deficiency by methemoglobin reduction test. Glutathione-S-Transferase (GST) gene polymorphism in sickle celled individuals and variant analysis in G6PD deficient individuals were analyzed by RT-PCR. ResultsThe frequency of SCA and G6PD deficiency was reported at 9.75% and 17.16% respectively and a high degree of positive correlation between SCA and G6PD deficiency was also found (HbSS-G6PD deficient: r = 0.84, p = .356; HbAS-G6PD deficient: r = 0.89, p = .345). Results of the GST gene revealed that GSTM1 and GSTT1 genes are present in almost all sickled individuals while GSTP1 and GSTP1a exist in the mutated form in a maximum percentage of individuals. G6PD variant analysis also showed that 70% and 60% of individuals have mutated Mahidol and Union variants respectively, while none of the individuals have mutated Chinese variants. ConclusionA high degree of correlation between SCA and G6PD was reported among Gond tribes of Chhattisgarh, India with a high degree of mutated GSTP1, GSTP1a, Mahidol, and Union variants. The study makes it possible to take specific preventive measures concerning the medication of anti-oxidizing drugs.

Survey for glucose-6- phosphate dehydrogenase enzyme deficiency among premarital attendanceinniava

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is considered the most frequent enzyme deficiency world wide, several reports have focused on its prevalence in different regions of Iraq. The current study was initiated to report on the frequency of G6PD deficiency among male attendance to premarital center in Ninava governorate in Northern Iraq. A total of 806 male individuals attending the Public Health Laboratory for routine premarital investigations were screened for G6PD deficiency using methemoglobin reduction test (MRT). The results were confirmed by quantitative enzyme assay for the cases that showed G6PD deficiency. A total (759) out of (806) were MRT negative , and (47) out of (806) were MRT positive with a prevalence of (5.8%).

DIAGNOSTIC ACCURACY COMPARISON OF THE QUANTITATIVE POINT-OF-CARE ECO G6PD AND BREWERS TEST FOR ASSESSMENT OF G6PD DEFICIENCY IN INFECTIOUS DISEASES

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked, hereditary condition caused by mutations in the G6PD gene, that results in protein variants with different enzyme activity levels. G6PD provides reducing power to NADPH (reduced form of nicotinamide adenine dinucleotide phosphate). NADPH effect is critical in red blood cells (RBC) due to the absence of a nucleus. Clinical manifestations are usually mild and are induced by an exogenous agent, such as drugs, infections, or dietary (fava beans). The G6PD deficiency diagnosis is crucial in infectious diseases because both infections and treatment can induce acute hemolysis. Rarely, life-threatening cases can require transfusions of RBC and hemodialysis. The gold standard for the measurement of G6PD activity is a quantitative UV spectrophotometric assay, however, it is inaccessible in most cases. Methemoglobin reduction test (Brewer's test) is a qualitative spot test most used for G6PD deficiency screening, but is imprecise, requires a cold chain, some laboratory infrastructure, trained personnel, and is time-costing. Point-of-care (POC) is a simple and fast semi-quantitative test that is becoming increasingly important when a prompt diagnosis is required and in health care of out-of-reach communities. To compare the diagnostic accuracy of the quantitative POC ECO and Brewers test for assessment of G6PD deficiency. A cross-sectional diagnostic accuracy study was enrolled between May 2020 and December 2021 at the Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz. Individuals older than 17 years old with a suspicious diagnosis of an infectious disease were eligible. 125 convenience blood samples were tested to compare concordance analysis between Brewers test and POC STANDARD G6PD. The exclusion criteria were hemoglobin concentration < 7.0 g/dL due to technical device limitations. A total of 125 subjects (38 females and 87 males) were recruited. The median age was 42.0 years (range 18–76) in females and 45.0 years (range 19–78) in males. The median of G6PD activity was 7.1 U/g Hb (0.2-17.5). We observed a trend of concordance between the G6PD status (deficient or normal), with low frequencies of discordances in the screenings. The strength of agreement between G6PD tests was classified as almost perfect in all participants (k = 0.82, IC95% = 0.66,0.97) and in subgroups female (k = 0.83, IC95% = 0.59,1.00) and male (k = 0.81, IC95% = 0.59,1.00). The total concordance percentage (number of concordances/total) was 95% in females, 97% in males, and 96% in all participants. Here, we demonstrate POC ECO G6PD test could be performed during medical consultation, guiding the most appropriate therapy almost immediately. In addition to saving time and having comparable results to Brewer's test, it could be performed even in remote areas and with scarce resources, dispensing minimum laboratory requirements. Our findings will be of value to diagnose conditions that could have life-threatening consequences if not timely recognized, such as before initiating primaquine for the treatment of malaria. Therefore, it can improve healthcare in vulnerable isolated communities. We observed a high concordance result between Brewers test and POC STANDARD G6PD, which is becoming the reference test to diagnose G6PD deficiency worldwide.

Deficiência da glicose-6-fosfato desidrogenase (G6PD) em recém-nascidos, numa maternidade pública da cidade de Campina Grande, Estado da Paraíba, Brasil

Nos eritrócitos deficientes de glicose 6 fosfato desidrogenase (G6PD), a diminuição da redução de NADP em NADPH, leva a um baixo potencial redutor que interfere na capacidade metabólica oxidativa do organismo, ficando vulnerável a hemólise, com oxidação da membrana do glóbulo, podendo levar a crise hemolíticas. As manifestações da deficiência de G6PD são desencadeadas por fatores ambientais como drogas, fava, infecções. As manifestações clínicas consistem de crise hemolítica e icterícia neonatal. Estudos indicam que no Brasil a prevalência de G6PD está em torno de 1 a 10%, sendo os maiores índices em populações com ancestralidade africana. O objetivo foi a pesquisa da deficiência da G6PD em recém-nascidos numa maternidade pública na cidade de Campina Grande. Trata-se de um estudo transversal, onde foram coletados sangue do cordão umbilical de 147 recém-nascidos. O diagnóstico da deficiência da G6PD será realizado através do teste da redução da metahemoglobina (teste de Brewer). A cidade de Campina Grande, bem como todo o Compartimento da Borborema não apresentam nenhum dado relativo a prevalência da deficiência da G6PD. O Ministério da Saúde fortalece através do SUS a coleta de informações relativas a esta doença na perspectiva de implantação de um programa de atenção à saúde dos doentes detectados, promovendo melhoras na sua qualidade de vida.

Prevalnce of G6PD deficiency amongst healthy blood donors

Introduction:Blood donation is very common procedure in clinical practice. Deficiency of G6PD is the most common erythrocyte enzymopathy and has been estimated to affect over 400 million people worldwide that may lead to neonatal jaundice or hemolytic crisis due to drugs or infections. By detecting such problem of deficiency of G6PD enzyme, we can prevent complications of blood transfusion. We can decide in whom to avoid such transfusions. Objectives:To study G6PD deficiency prevalence in healthy blood donors; according to age, sex, ABO blood group and Rh blood Group distribution. Material and methods: Qualitative method by Methaemoglobin Reduction test (MRT) was used for screening of the blood donors for G6PD deficiency. Quantitative test of all positive donors by qualitative method was done by semi-automated G6PD reagent kit. Observational Cross-sectional study involving 1012 healthy blood donors for period of 9 months was done. Results: It was observed that 35 (3.5%) blood donors were G6PD deficient amongst 1012 blood donors. The prevalence rate for G6PD deficiency observed in this study was 3.5%. Conclusion: The observation of 3.5% prevalence of G6PD deficient blood donors in the present study could be taken to consider that the problem of G6PD deficiency exists in the blood donors. It should be of concern as the G6PD deficiency remains obscure, there being no overt clinical manifestation. Prevalence of 3.5% should be taken as serious concern and further more studies are advised for screening of G6PD in healthy blood donors.

Glucose-6-Phosphate Dehydrogenase Deficiency and Sickle Cell Trait among Prospective Blood Donors: A Cross-Sectional Study in Berekum, Ghana.

Background. Blood transfusion is a therapeutic procedure usually undertaken in patients with severe anaemia. In Ghana, severe anaemia is mostly due to malaria caused by severe Plasmodium falciparum infection, road traffic accidents, and haemoglobinopathy-induced acute haemolysis. Method. This cross-sectional study evaluated coinheritance of sickle cell haemoglobin variant and G6PD enzymopathy among individuals that donated blood at the Holy Trinity Hospital, Berekum, in the Brong-Ahafo Region, Ghana. Demographic data and other pertinent information were captured using questionnaire. Sickle cell haemoglobin variants were determined using cellulose acetate electrophoresis (pH 8.6). Qualitative G6PD status and quantitative G6PD enzyme activity were determined using methaemoglobin reduction and Trinity Biotech G6PD test kit, respectively. Results. Prevalence of sickle cell trait (SCT) and G6PD enzymopathy coinheritance was 7%. In addition, 19.5% of the donors had 10%–60% of normal G6PD enzyme activity suggesting that these donor units are prone to stressor-induced acute haemolysis when given to recipients. Mild G6PD activity (p = 0.03, OR: 2.410 (CI: 1.049–5.534)), commercial (p = 0.020, OR: 5.609 (CI: 1.309–24.035)), and voluntary (p = 0.034, OR: 2.404 (CI: 1.071–5.397)) donors were significantly associated with SCT. Conclusion. Screening for red cell pathologies must be incorporated into existing protocols for populations with high incidence of haemoglobinopathies to protect high-risk recipients.

Study of the common genotype of glucose-6-phosphate dehydrogenase deficiency in newborn infant in Guangdong region

Objective To investigate the genotypic frequency of glucose-6-phosphate dehydrogenase(G6PD)(1376G>T), G6PD 1311C>T and G6PD IVS11-93 T>C in 50 newborns with G6PD deficiency in Guangdong region. Methods To identify G6PD deficiency in the patients of neonatal ward in Guangzhou First People's Hospital during 2010, detected by methemoglobin reduction test and measurement of G6PD/6-phosphate dehydrogenase(6PGD) ratio.Fifty G6PD deficiency subjects were classified into the experimental group, 20 neonatal jaundice subjects were classified into the control group.Genomic DNA was extracted by standard method from the peripheral blood of each subject.PCR-direct DNA sequence analysis was used to identify G6PD 1376G>T, 1311C>T and 11 intron 93T>C mutations. Results The overall results of mutation analysis in the 50 G6PD deficiency subjects showed the existence of 3 different alleles: G6PD 1376G>T, 1311C>T, 11 intron 93T>C(including 1311C>T/IVS11-93T>C and 1376G>T/1311C>T/IVS11-93T>C complex mutations). The different genotypic frequency in the experimental group was G6PD 1376G>T 26.0%(13/50 cases), 1311C>T 4.0%(2/50 cases), 11 intron 93T>C 4.0%(2/50 cases), 1311C>T/IVS11-93T>C 2.0%(1/50 cases), 1376G>T/1311C>T/IVS11-93T>C 2.0%(1/50 cases). The G6PD enzyme activity of the subjects with 1311C>T/IVS11-93T>C and 1376G>T/1311C>T/IVS11-93T>C complex mutation were reduced.These G6PD mutations were not found in the controls. Conclusions G6PD 1376G>T is one of the commonest mutation in G6PD deficiency newborn in Guangdong region.A novel complex mutation 1376G>T/1311C>T/IVS11-93T>C in this study was found. Key words: Glucose-6-phosphate dehydrogenase; Complex mutations; Infant, newborn; Guangdong

Glucose-6-Phosphate Dehydrogenase (G6pd) Deficiency and Sickle Cell Trait among Blood Donors in Nigeria

This study is being aimed to determine the prevalence of glucose-6-phosphate dehydrogenase deficiency and sickle cell trait among blood donors. Blood donation from glucose-6-phosphate dehydrogenase (G6PD)-deficient and sickle cell trait (SCT) donors might alter the quality of the donated blood during processing, storage or in the recipient′s circulatory system. It has been proposed that several biochemical changes and depletion in the antioxidant defense system occur on storage of G6PD-deficient blood. Red blood cells collected from sickle cell trait donors frequently occlude white blood cells reduction filters; the main cause of this filtration failure is haemoglobin polymerization. A total of 314 blood donor samples were collected from prospective and healthy blood donors after proper screening. Glucose-6-Phosphate dehydrogenase was determined using two standard methods; methaemoglobin reduction test and fluorescent spots test; haemoglobin variants were determined using cellulose acetate electrophoresis at alkaline PH 8.6. Out of the 314 blood donors, 80 (25.5%) were G6PD deficient, 104 haemoglobin variants AS, AC and SC were 82 (78.8%), 21 (20.2%) and 1 (1.0%) respectively. Commercial blood donors had highest G6PD deficient and highest haemoglobin variants. Age group 25-34 had highest G6PD deficient prevalence while age group 15-24 had highest haemoglobin variants. Transfusion with G6PD-deficient blood carries a potential risk of hemolytic complications, especially if it is used for exchanged blood transfusion in neonates. On the other hand, the blood donated from SCT donors, apart from its undesired effects if transfused to sickle cell disease patients, also leads to WBC filtration failure.

Evaluation of the phenotypic test and genetic analysis in the detection of glucose-6-phosphate dehydrogenase deficiency

BackgroundGlucose-6-phosphate dehydrogenase (G6PD) deficiency is particularly prevalent in historically malaria-endemic countries. Although most individuals with G6PD deficiency are asymptomatic, deficiency can result in acute haemolytic anaemia after exposure to oxidative agents. A reliable test is necessary for diagnosing the deficiency to prevent an acute haemolytic crisis following, for example, anti-malarial treatment. The aim of this study was to investigate which method was the best predictor of this disorder.MethodsThe present study investigated four G6PD activity detections (fluorescence spot (FS), methaemoglobin reduction (MR), biochemical and cytochemical test). These methods accompanied with mutation analysis of blood samples were taken from 295 apparently healthy individuals with unknown G6PD deficiency status.ResultsMolecular characterization of 295 Thai adults revealed an overall prevalence of 14.2%. The G6PD Viangchan (871 G>A) was the most common (83.3%), followed by G6PD Mahidol (487G>A) (11.9%), and G6PD Union (1360 C>T) (4.8%). There were two cases of G6PD deficiency carrying the double mutations of Viangchan (871G > A)-Mahidol (487G > A) and Viangchan (871G > A)-Union (1360C > T). In comparison, the prevalence of G6PD deficiency was 6.1% by FS test and 7.1% by MR test. G6PD activity was 11 ± 2.5 IU/gHb in non-deficient females (mean ± SD), and 10.9 ± 0.6 IU/gHb in non-deficient males. The upper and lower limit cut-off points for partial and severe deficiency in adults were 5.7 IU/gHb (60% of the normal mean) and 0.95 IU/gHb (10% of the normal mean), respectively. All hemizygote, homozygote and double mutations were associated with severe enzyme deficiency (the residual enzyme activity <10% of the normal mean), whereas only 14.3% of the heterozygote mutations showed severe enzyme deficiency. Based on the cut-off value <5.7 IU/gHb, the quantitative G6PD assay diagnosed 83% of cases as G6PD-deficient. Using a cut-off number of negative cell >20% in the cytochemical assay to define G6PD deficiency, the prevalence of G6PD deficiency was closest to the molecular analysis (12.9% G6PD-deficient) compared to the others methods.ConclusionThe cytochemical method is a significant predictor of this disease, while FS and MR test are recommended for the detection of severe G6PD deficiency in developing countries.

The role of erythrocyte enzyme glucose-6-phosphate dehydrogenase (G6PD) deficiency in the pathogenesis of anemia in patients on hemodialysis

Anemia is a common feature among patients with chronic renal failure (CRF). Low activity of the erythrocyte enzyme glucose-6-phosphate dehydrogenase (G6PD), which plays a major role in protecting red blood cells against oxidative agents, has been described as one of the contributing factors to anemia in patients with CRF treated with hemodialysis (HD). In this study, blood samples were randomly collected from 65 patients on HD and investigated for G6PD deficiency using the methemoglobin reduction test. The hemoglobin (Hb) concentration, packed cell volume (PCV), red blood cells (RBCs) count and reticulocyte count were determined in all the samples. Our results showed that 39 of 65 patients (60%) on HD had low G6PD activity and 26 (40%) patients had normal activity; 59% of the patients with low G6PD activity were males. The mean Hb, PCV and RBCs counts were lower in patients with low G6PD activity than in those with normal G6PD activity, but the difference was not statistically significant. Likewise, no statistically significant difference was found in the reticulocyte count in patients with low G6PD activity and in those with normal G6PD activity. The low G6PD activity that was found in a large proportion of patients on HD seems to be the result of enzyme inhibition rather than deficiency. No statistically significant difference was found in anemia parameters between patients with and without G6PD deficiency.

Molecular characterization of glucose-6-phosphate dehydrogenase deficient variants in Baghdad city - Iraq

BackgroundAlthough G6PD deficiency is the most common genetically determined blood disorder among Iraqis, its molecular basis has only recently been studied among the Kurds in North Iraq, while studies focusing on Arabs in other parts of Iraq are still absent.MethodsA total of 1810 apparently healthy adult male blood donors were randomly recruited from the national blood transfusion center in Baghdad. They were classified into G6PD deficient and non-deficient individuals based on the results of methemoglobin reduction test (MHRT), with confirmation of deficiency by subsequent enzyme assays. DNA from deficient individuals was studied using a polymerase chain reaction-Restriction fragment length polymorphism (PCR-RFLP) for four deficient molecular variants, namely G6PD Mediterranean (563 C→T), Chatham (1003 G→A), A- (202 G→A) and Aures (143 T→C). A subset of those with the Mediterranean variant, were further investigated for the 1311 (C→T) silent mutation.ResultsG6PD deficiency was detected in 109 of the 1810 screened male individuals (6.0%). Among 101 G6PD deficient males molecularly studied, the Mediterranean mutation was detected in 75 cases (74.3%), G6PD Chatham in 5 cases (5.0%), G6PD A- in two cases (2.0%), and G6PD Aures in none. The 1311 silent mutation was detected in 48 out of the 51 G6PD deficient males with the Mediterranean variant studied (94.1%).ConclusionsThree polymorphic variants namely: the Mediterranean, Chatham and A-, constituted more than 80% of G6PD deficient variants among males in Baghdad. Iraq. This observation is to some extent comparable to other Asian Arab countries, neighboring Turkey and Iran.

A novel cytofluorometric assay for the detection and quantification of glucose-6-phosphate dehydrogenase deficiency

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked enzymopathy that affects hundreds of millions of people worldwide, conferring increased risk of neonatal jaundice and oxidant-induced hemolytic anemia. Screening and diagnosis of G6PD deficiency is currently performed using genetic or biochemical assays, the former being cost ineffective in populations with significant allelic heterogeneity, and the latter being limited in ability to detect female heterozygotes. Cytochemical assays can obviate these shortcomings, but at the expense of added technical complexity and labor. We describe here a simple, novel cytofluorometric method that extends the classic methemoglobin reduction test, assessing G6PD deficiency at the level of an individual erythrocyte. In preliminary testing in Malian children, there was strong concordance between our method and established genetic and biochemical techniques. The assay is robust and economical, and could serve as a screening method as well as a research tool, especially for high-throughput applications such as flow cytometry.

Screening for G6PD Deficiency in Blood Donor Population

Dear Editor, Glucose-6-phosphate dehydrogenase deficiency is the most common enzyme deficiency worldwide. Approximately 400 million people are said to be affected worldwide. According to world health organization 7.5% of world population are carriers of glucose-6-phosphate dehydrogenase deficiency and 2.9% were G6PD deficient [1]. It causes spectrum of diseases including neonatal hyperbilirubinemia, acute hemolytic and chronic hemolytic anemia. Usually the affected individuals are asymptomatic unless they are provoked by oxidative stress [2]. This enzyme deficiency is very prevalent in individuals of Africa, America, Mediterranean, and East Asia. In India the incidence of G6PD has been variably reported as 0–37% in different castes and communities. Higher incidence of G6PD deficiency is seen in north and west India (15%) as compared to south India (1–2%) [3]. It implies that this inherited metabolic disorder is an important health problem in India and it is necessary to carryout large scale screening in the whole population. Severe manifestations of G6PD deficiency can be prevented if necessary precautions are taken, hence this study was done to determine the incidence of G6PD deficiency in asymptomatic population represented by healthy blood donors and to characterize the demographic profile and laboratory profile of such group. The study was conducted on 2005 healthy blood donor samples. This screening program included 2000 male and 5 female blood donors who came to blood bank for donation of blood. These donors were from different part of India. The G6PD activity was assessed in their red cells using anticoagulated (EDTA) venous blood. Sixteen blood donors out of 2005 screened by methaemoglobin reduction test were found to be G6PD deficient. All of them were male. These individuals were clinically normal and had no significant past history. The incidence of G6PD deficiency was 0.8% in the sampled population. Among this 16 G6PD deficient subjects two blood donors were from West Bengal, one from Kerala and the rest of the 13 subjects were from Karnataka. The mean Haemoglobin values of the normal donor population vs. G6PD deficient donor population were compared using unpaired t test. The difference in the mean Hb value was not statistically significant (P value > 0.5). Sixteen units of blood were transfused to patients. There was two [12.5%] transfusion related reaction among the patients who received the G6PD deficient blood. One of the patients, who was transfused following upper Gastro intestinal bleeding, had itching and rashes all over the body after transfusion of 50 ml blood. The reaction workup done ruled out haemolytic reaction. A probability of allergic reaction was considered. As in this patient transfusion was stopped and he did not receive further transfusions for next 48 h, his Hb fell from 9.0 to 7.7 gm/dl. The second patient was a neonate undergoing surgery for a ruptured meningomyelocoele. The blood was transfused during surgery following which the baby developed mottling and passed red colored urine. A hemolytic transfusion was suspected. The transfusion reaction workup showed haemolysis in the post transfusion sample and hemoglobinuria. But blood bag showed no hemolysis. However as pretransfusion sample also showed haemolysis, a hemolytic reaction could not be conclusively reported. Hemoglobin dropped from 12.2 to 8.0 gm/dl. The beneficial effects of blood transfusion, for the typical 70 kg human each unit of whole blood should increase the hematocrit by 3–5% or hemoglobin by 1–1.5 gm/dl [4].Testing for G6PD deficiency is not routinely practiced for donors units [2]. Various studies have reported a mild increase in bilirubin, LDH, and decrease in hemoglobin following the transfusion of G6PD deficient blood. This is especially in neonates (preterm). Transfusion of G6PD deficient red cells to the premature infants has been associated with hemolytic and severe hyperbilirubinemia requiring exchange transfusion [5]. In our study also one neonate developed suspected hemolytic transfusion reaction following transfusion of G6PD deficient blood. Under normal circumstances the transfusion of G6PD deficient blood is harmless for most of the individuals until they are exposed to certain oxidative drugs. This study was an attempt to find out the prevalence of G6PD deficiency in our population. This will help us to quantitate the magnitude of the problem in the population and initiate measures to screen the population or a selected group in the population. The prevalence of G6PD being very low in this study (0.8%) and as many people remain asymptomatic unless challenged with oxidative drugs or infection, screening the whole population for G6PD deficiency is not warranted. As one of the neonates receiving G6PD deficient blood developed suspected hemolytic reaction, screening of blood to be transfused for select population like neonates is advisable.

Prevalence and molecular characterization of Glucose-6-Phosphate dehydrogenase deficient variants among the Kurdish population of Northern Iraq

BackgroundGlucose-6-Phosphate dehydrogenase (G6PD) is a key enzyme of the pentose monophosphate pathway, and its deficiency is the most common inherited enzymopathy worldwide. G6PD deficiency is common among Iraqis, including those of the Kurdish ethnic group, however no study of significance has ever addressed the molecular basis of this disorder in this population. The aim of this study is to determine the prevalence of this enzymopathy and its molecular basis among Iraqi Kurds.MethodsA total of 580 healthy male Kurdish Iraqis randomly selected from a main regional premarital screening center in Northern Iraq were screened for G6PD deficiency using methemoglobin reduction test. The results were confirmed by quantitative enzyme assay for the cases that showed G6PD deficiency. DNA analysis was performed on 115 G6PD deficient subjects, 50 from the premarital screening group and 65 unrelated Kurdish male patients with documented acute hemolytic episodes due to G6PD deficiency. Analysis was performed using polymerase chain reaction/restriction fragment length polymorphism for five deficient molecular variants, namely G6PD Mediterranean (563 C→T), G6PD Chatham (1003 G→A), G6PD A- (202 G→A), G6PD Aures (143 T→C) and G6PD Cosenza (1376 G→C), as well as the silent 1311 (C→T) mutation.ResultsAmong 580 random Iraqi male Kurds, 63 (10.9%) had documented G6PD deficiency. Molecular studies performed on a total of 115 G6PD deficient males revealed that 101 (87.8%) had the G6PD Mediterranean variant and 10 (8.7%) had the G6PD Chatham variant. No cases of G6PD A-, G6PD Aures or G6PD Cosenza were identified, leaving 4 cases (3.5%) uncharacterized. Further molecular screening revealed that the silent mutation 1311 was present in 93/95 of the Mediterranean and 1/10 of the Chatham cases.ConclusionsThe current study revealed a high prevalence of G6PD deficiency among Iraqi Kurdish population of Northern Iraq with most cases being due to the G6PD Mediterranean and Chatham variants. These results are similar to those reported from neighboring Iran and Turkey and to lesser extent other Mediterranean countries.

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.

Erythrocyte glucose-6-phosphate dehydrogenase deficiency in male newborn babies and its relationship with neonatal jaundice

Glucose-6-phosphate dehydrogenase (G6PD) deficiency, the commonest red cell enzymopathy in humans, has an X-linked inheritance. The major clinical manifestations are drug induced hemolytic anemia, neonatal jaundice and chronic nonspherocytic hemolytic anemia. The incidence of neonatal hyperbilirubinemia is much greater in G6PD-deficient neonates than babies without this deficiency. The aim of this study was to ascertain the presence of neonatal jaundice in erythrocyte G6PD-deficient male newborns. Samples of umbilical cord blood from a total of 204 male newborns of the Januário Cicco School Maternity located in Natal, Rio Grande do Norte, Brazil were analyzed. The G6PD deficiency was identified by the methemoglobin reduction test (Brewer's test). The deficiency was confirmed by quantitative spectrophotometric assay for enzyme activity and cellulose acetate electrophoresis was used to identify the G6PD variant. Eight newborns were found to be G6PD deficient with four of them exhibiting jaundice during the first 48 hours after birth with bilirubin levels higher than 10 mg/dL. All deficient individuals presented the G6PD A- variant at electrophoresis. Our findings confirmed the association between G6PD deficiency and neonatal jaundice. Hence, early diagnosis of the deficiency at birth is essential to control the appearance of jaundice and to prevent the exposure of these newborns to known hemolytic agents.

Prevalência da deficiência da glicose-6-fosfato desidrogenase em doadores de sangue de 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%, 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.

Frequência da deficiência de glicose-6-fosfato desidrogenase (G-6-PD) e sua relação com a icterícia neonatal

Abstract Glucose-6-phosphate dehydrogenase (G-6-PD) deficiencyis the most common enzyme deficiency with its main clinicalmanifestations being hemolysis induced by drugs and neonataljaundice. The aim of this study was to investigate the frequencyof G-6-PD deficiency in newborns and verify its relationshipwith neonatal jaundice. A total of 450 blood samples of full-termnewborns that presented with jaundice within the first week oflife were analyzed, including 400 umbilical cord blood samples(Group I) and 50 peripheral blood samples (Group II). All ofthem originated from Public Healthcare Clinics of Natal, Rio Gran-de do Norte, Brazil. The methemoglobin reduction test (Brewer'stest) was carried out for all blood samples. Deficiency wasconfirmed by quantitative spectrophotometric assay for enzymeactivity and cellulose acetate electrophoresis in order to assessthe G-6-PD variant. Eight G-6-PD deficient individuals werediagnosed among the 400 cord blood samples giving a frequencyof 2%. Among boys, the frequency was 3.9% but no deficientgirls were identified. Four neonates (50%) with G-6-PD deficiencysuffered jaundice within the first 48 hours of life. All of themdeveloped moderate jaundice showing bilirubin levels higher than10.0 mg/dL. Of the 50 newborns that presented with jaundice inthe first week of life, the frequency of G-6-PD deficiency was 8%(4/50). All G-6-PD-deficient neonates (Groups I and II) had anAfrican variant (G6PD A-). The results of this study confirmedthe association between G-6-PD deficiency and neonatal jaundice.Precocious diagnosis of the deficiency through neonatal screeningis essential to control jaundice and to prevent exposure of thesenewborns to known hemolytic agents.

A novel c.197T &lt;FONT FACE=Symbol&gt;®&lt;/FONT&gt; A variant among Brazilian neonates with glucose-6-phosphate dehydrogenase deficiency

Glucose-6-phosphate dehydrogenase (G6PD, EC 1.1.1.49) deficiency is the most common enzyme deficiency worldwide, causing a spectrum of diseases including neonatal hyperbilirubinemia and acute or chronic hemolysis. We used the methemoglobin reduction test and G6PD electrophoresis to screen 655 neonates (354 females and 301 males) for common G6PD mutations in the city of Salvador in the Northeastern Brazilian state Bahia and found that 66 (10.1%) were G6PD-deficient (41 females and 25 males). The 66 (10.1%) G6PD-deficient neonates were assessed for the c.376 A → G (exon 5) and c.202 G → A (exon 4) mutations using the polymerase chain reaction and restriction enzyme fragment length polymorphism (PCR-RFLP) analysis and the results validated by DNA sequencing. Of the 66 G6PD-deficient neonates investigated we found that 54 (81.8%) presented the c.376 A → G (p.Asn126Asp) and c.202 G→A (p.Val68Met) mutations, two (3%) had the c.376 A→G mutation only, two (3%) had the c.202 G→A mutation only, five (7.6%) exhibited a previously unrecorded 197T→A (p.Phe66Thr) substitution in exon 4 and three showed no mutations at any of these sites. Of the five neonates exhibiting the new 197T → A (p.Phe66Thr) substitution, four (6.1%) also presented the c.202 G → A and c.376 A → G mutations and one (1.5%) had the c.[197T → A / 202 G → A] combination. We propose to name the new variant G6PD Bahia

Effects of ABO/Rh blood groups, G-6-P-D enzyme activity and haemoglobin

The main objective was to investigate the effects of ABO/Rh blood groups, haemoglobin genotype and G-6-P-D enzyme activity on malaria. The study was carried out in Buea, South West Province, Cameroon. Subjects consulting at health care facilities in Buea were randomly recruited into the study. A total of 121 febrile patients 1-60 years old comprised the study subjects. Thin and thick blood films were prepared for malaria parasite detection. G-6-P-D enzyme activity was assayed using the met-haemoglobin reduction test. Determination of haemoglobin genotypes was by a rapid screening method alongside electrophoresis. Malaria positive patients were treated. The highest malaria prevalence of 74.5 % was in Group O individuals and the lowest of 58.6% in group B individuals. Mean parasite density (Log(10)(-1)/ul blood) in the various blood groups was not significantly different. Individuals with G-6-P-D deficiency had a significantly lower malaria prevalence (47.5%) when compared with active individuals. Mean parasite density in enzyme deficient and active individuals was 3.7(SD+/- 3.9) and 4.4(SD +/-5.0) respectively and the difference was significant (p < 0.05). Malaria prevalence was lower (57.5%) in HbS individuals when compared with HbAA (74.6%) and HbSS (60%) but parasite density was not significantly different. Our results suggest that individuals with blood group O who have the HbAA genotype and show G-6-P-D enzyme activity may be more susceptible to malaria. Information on the influence of these genetic factors on malaria would be useful in the better management of the disease in the study area.