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Red cell diseases encompass a group of inherited or acquired erythrocyte disorders that affect the structure, function, or production of red blood cells (RBCs). These disorders can lead to various clinical manifestations, including anemia, hemolysis, inflammation, and impaired oxygen-carrying capacity. Oxidative stress, characterized by an imbalance between the production of reactive oxygen species (ROS) and the antioxidant defense mechanisms, plays a significant role in the pathophysiology of red cell diseases. In this review, we discuss the most relevant oxidant species involved in RBC damage, the enzymatic and low molecular weight antioxidant systems that protect RBCs against oxidative injury, and finally, the role of oxidative stress in different red cell diseases, including sickle cell disease, glucose 6-phosphate dehydrogenase deficiency, and pyruvate kinase deficiency, highlighting the underlying mechanisms leading to pathological RBC phenotypes.

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Acquired Hemophagocytic Lymphohistiocytosis is a rare and deadly syndrome resulting from an overactive immune system, with uncontrolled activation of macrophages and lymphocytes, hypercytokinemia, and systemic inflammatory response. A 75-year-old male presented with typical anginal pain and was diagnosed with the acute coronary syndrome, which required a percutaneous transluminal coronary angioplasty. Instead of resolving the symptoms, the patient began to exhibit pyrexia and worsening altered sensorium with progressing renal failure, anemia, thrombocytopenia and respiratory failure. This constellation of symptoms caused the patient to require mechanical ventilation and hemodialysis. Upon laboratory analysis, hyperferritinemia provided an indication to the diagnosis of acquired hemophagocytic lymphohistiocytosis. After the initiation of dexamethasone, the patient made a significant recovery and was discharged from the hospital.

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BACKGROUND: Glucose-6-phosphate dehydrogenase deficiency (G6PDd) newborn screening is still a matter of debate due to its highly heterogeneous birth prevalence and clinical expression, as well as, the lack of enough knowledge on its natural history. Herein, we describe the early natural clinical course and the underlying GDPD genotypes in infants with G6PDd detected by newborn screening and later studied in a single follow-up center. G6PDd newborns were categorized into three groups: group 1: hospitalized with or without neonatal jaundice (NNJ); group 2: non-hospitalized with NNJ; and group 3: asymptomatic. Frequencies of homozygous UGT1A1*28 (rs34983651) genotypes among G6PDd patients with or without NNJ were also explored. RESULTS: A total of 81 newborns (80 males, one female) were included. Most individuals (46.9%) had NNJ without other symptoms, followed by asymptomatic (42.0%) and hospitalized (11.1%) patients, although the hospitalization of only 3 of these patients was related to G6PDd, including NNJ or acute hemolytic anemia (AHA). Nine different G6PDd genotypes were found; the G6PD A-202A/376G genotype was the most frequent (60.5%), followed by the G6PD A-376G/968C (22.2%) and the Union-Maewo (rs398123546, 7.4%) genotypes. These genotypes produce a wide range of clinical and biochemical phenotypes with significant overlapping residual enzymatic activity values among class I, II or III variants. Some G6PD A-202A/376G individuals had enzymatic values that were close to the cutoff value (5.3 U/g Hb, 4.6 and 4.8 U/g Hb in the groups with and without NNJ, respectively), while others showed extremely low enzymatic values (1.1 U/g Hb and 1.4 U/g Hb in the groups with and without NNJ, respectively). Homozygosity for UGT1A1*28 among G6PDd patients with (11.9%, N = 5/42) or without (10.3%, N = 4/39) NNJ did not shown significant statistical difference (p = 0.611). CONCLUSION: Wide variability in residual enzymatic activity was noted in G6PDd individuals with the same G6PD genotype. This feature, along with a documented heterogeneous mutational spectrum, makes it difficult to categorize G6PD variants according to current WHO classification and precludes the prediction of complications such as AHA, which can occur even with > 10% of residual enzymatic activity and/or be associated with the common and mild G6PD A-376G/968C and G6PD A-202A/376G haplotypes.

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Acquired Hemophagocytic Lymphohistiocytosis is a rare and deadly syndrome resulting from an overactive immune system, with uncontrolled activation of macrophages and lymphocytes, hypercytokinemia, and systemic inflammatory response. A 75-year-old male presented with typical anginal pain and was diagnosed with the acute coronary syndrome, which required a percutaneous transluminal coronary angioplasty. Instead of resolving the symptoms, the patient began to exhibit pyrexia and worsening altered sensorium with progressing renal failure, anemia, thrombocytopenia and respiratory failure. This constellation of symptoms caused the patient to require mechanical ventilation and hemodialysis. Upon laboratory analysis, hyperferritinemia provided an indication to the diagnosis of acquired hemophagocytic lymphohistiocytosis. After the initiation of dexamethasone, the patient made a significant recovery and was discharged from the hospital.

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ABSTRACT The aim of this study has been to study whether the top-down method, based on the average value identified in the Brazilian Hospitalization System (SIH/SUS), is a good estimator of the cost of health professionals per patient, using the bottom-up method for comparison. The study has been developed from the context of hospital care offered to the patient carrier of glucose-6-phosphate dehydrogenase (G6PD) deficiency with severe adverse effect because of the use of primaquine, in the Brazilian Amazon. The top-down method based on the spending with SIH/SUS professional services, as a proxy for this cost, corresponded to R$60.71, and the bottom-up, based on the salaries of the physician (R$30.43), nurse (R$16.33), and nursing technician (R$5.93), estimated a total cost of R$52.68. The difference was only R$8.03, which shows that the amounts paid by the Hospital Inpatient Authorization (AIH) are estimates close to those obtained by the bottom-up technique for the professionals directly involved in the care.

RESUMO A pesquisa teve por objetivo estudar se o macrocusteio, baseado no valor médio identificado no Sistema de Internação Hospitalar (SIH/SUS), constitui um bom estimador do custo de profissionais de saúde por paciente, tendo como comparação o método de microcusteio. O estudo foi desenvolvido no contexto da assistência hospitalar oferecida ao portador da deficiência de glicose-6-fosfato desidrogenase (dG6PD) do sexo masculino com evento adverso grave devido ao uso da primaquina, na Amazônia Brasileira. O macrocusteio baseado no gasto em serviços profissionais do SIH/SUS, como proxy desse custo, correspondeu a R$60,71, e o microcusteio, baseado nos salários do médico (R$30,43), do enfermeiro (R$16,33) e do técnico de enfermagem (R$5,93), estimou um custo total de R$52,68. A diferença foi de apenas R$8,03, mostrando que os valores pagos pela Autorização de Internação Hospitalar (AIH) são estimadores próximos daqueles obtidos por técnica de microcusteio para os profissionais envolvidos diretamente no cuidado.

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Abstract: INTRODUCTION: In the Brazilian Amazon, malaria infections are primarily caused by Plasmodium vivax. The only drug that kills the hypnozoite form of P. vivax is primaquine, thereby preventing relapse. However, treating glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals with primaquine can lead to severe hemolysis. G6PD deficiency (G6PDd) affects approximately 400 million people worldwide, most of whom live in malaria-endemic areas. Therefore, clinicians need tools that can easily and reliably identify individuals with G6PDd. This study estimated the accuracy of the Carestart(tm) G6PD rapid test (Access Bio) in the diagnosis of G6PDd in male participants with and without P. vivax acute malaria. METHODS: Male participants were recruited in Manaus. Malaria diagnosis was determined by thick blood smear. G6PD quantitative analysis was performed spectro photometrically at a wave length of 340nm. The Carestart(tm) G6PD test was performed using venous blood. Genotyping was performed for individuals whose samples had an enzyme activity less than 70% of the normal value. RESULTS: Six hundred and seventy-four male participants were included in this study, of whom 320 had a diagnosis of P. vivax malaria. In individuals with enzyme activity lower than 30% (n=13), the sensitivity, specificity, positive predictive value, and negative predictive value of the Carestart(tm) G6PD test were as follows: 61.5% (95%CI: 35.5%-82.3%), 98.3% (95%CI: 97.0%-99.1%), 42.1% (95%CI: 23.1%-63.7%), and 99.2% (95%CI: 98.2%-82.3%), 98.3% (95%CI: 97.0%-99.1%), 42.1% (95%CI: 23.1%-63.7%), and 99.2% (95%CI: 98.2%-99.7%), respectively. Increases in sensitivity were observed when increasing the cut-off value. CONCLUSIONS: Despite low sensitivity, Carestart(tm) G6PD remains a good alternative for rapid diagnosis of G6PDd in malaria-endemic regions.

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BACKGROUND: Extensive studies investigating the role of host genetic factors during malaria associate glucose-6-phosphate dehydrogenase deficiency with relative protection. G6PD deficiency had been reported to associate with anti-malarial drug induced with haemolytic anaemia. METHODS: A total of 301 Gabonese, Ghanaian, and Kenyan children aged 6-120 months with severe malaria recruited in a multicentre trial on artesunate were included in this sub-study. G6PD normal (type B), heterozygous (type A(+)) and deficient (type A(-)) genotypes were determined by direct sequencing of the common African mutations G202A and A376G. Furthermore, multivariate analyses were executed to associate possible contributions of G6PD deficiency with baseline haemoglobin levels, parasitaemia and with severe malarial anaemia. RESULTS: Two hundred and seventy-eight children (132 females and 146 males) were successfully genotyped for G6PD variants. The overall prevalence of G6PD deficiency was 13 % [36/278; 3 % (4/132) female homozygous and 22 % (32/146) male hemizygous], 14 % (40/278) children were female heterozygous while 73 % (202/278) were G6PD normal [67 % (88/132) females and 78 % (114/146) males] individuals. Multivariate regression revealed a significant association of moderately and severely deficient G6PD genotypes with haemoglobin levels according to the baseline data (p < 0.0001; G6PD heterozygous: p < 0.0001; G6PD deficient: p = 0.009), but not with severe malarial anaemia (p = 0.66). No association of G6PD genotypes with baseline parasitaemia. CONCLUSIONS: In this study, moderately (type A(+)) and severely (type A(-)) G6PD deficiency showed significant association with lower haemoglobin concentrations at baseline in African children with severe malaria without leading to severe malarial anaemia. In addition, there was no association of G6PD variant types with parasite densities on admission.

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BACKGROUND: The treatment of Plasmodium vivax infections requires the use of primaquine, which can lead to severe haemolysis in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals. However, most of the Latin American countries, which are still endemic for vivax malaria, lack information on the distribution of G6PD deficiency (G6PDd). No survey has been performed so far in French Guiana. Herein, 80 individuals of the French Guianan Noir Marron population were scrutinized for red cell surface antigens of six blood group systems (ABO, Rh, Kell, Kidd, Duffy and MNS) and G6PD genetic polymorphisms. First, the sub-Saharan origin of the red cell phenotypes was assessed in relation with the literature. Then, given that the main sub-Saharan G6PDd variants are expected to be encountered, only the G6PD sequences of exons 4, 5, 6 and 9 were screened. This work aims at appraising the G6PD gene variation in this population, and thus, contributing to the G6PD piecemeal information in Latin America. RESULTS: Ninety-seven percent (97 %) of the red cells are Fy(a- b-), either D+ C- E- c+ e+ or D+ C+ E- c+ e+ and 44 % exhibited the Fya-/Jkb-/S- combined phenotype. Noteworthy is the detection of the G6PD(Val68Met) variant characterized by c.202G > A transition, G6PD(Asn126Asp) variant characterized by c.376A>G transition and G6PD(Asp181Val) variant characterized by c.542A>T transversion of the G6PD gene in 22.5 % of the sample, characteristic of the A(-(202)), A and Santamaria G6PDd variants, respectively. CONCLUSIONS: French Guianan Noir Marron population represents a pool of Rh-D antigen positive, Duffy-negative and G6PD-deficient erythrocytes, the latter accounting for one in every eight persons. The present study provides the first community-based estimation of the frequency of G6PDd polymorphisms in French Guiana. These results contribute to the G6PD genetic background information puzzle in Latin America.

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The co-inheritance of erythrocyte defects, hemoglobinopathies, enzymopathies, and membranopathies is not an unusual event. For the diagnosis, a laboratory strategy, including screening and confirmatory tests, additional to molecular characterization, was designed. As the result of this approach, a 24-year-old man carrying a hemoglobinopathy (Hemoglobin Woodville) and an enzymopathy (glucose-6-phosphate dehydrogenase deficiency) was identified. In the heterozygous state hemoglobin Woodville, is asymptomatic, and homozygous or double heterozygous individuals have not been reported thus far. On the other hand, previously described double point mutation in the gene for glucose-6-phosphate dehydrogenase c. [202G>A; 376A>G], p. [Val 68Met; Asn126Asp], causes hemolysis of varying severity after food or drug intake or infections. This case highlights the importance of the methodology carried out for the diagnosis, treatment, and proper genetic counseling.

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En Argentina la pesquisa neonatal es obligatoria por ley para ciertas condiciones, pero no para la deficiencia de Glucosa-6-Fosfato Deshidrogenasa (G6PD). La deficiencia de G6PD es un trastorno ligado al cromosoma X que puede causar ictericia neonatal, eventualmente kernicterus y hemólisis intravascular aguda en asociación a la exposición a sustancias oxidantes, la ingestión de ciertos alimentos, drogas o medicamentos, algunas infecciones, o cualquier otra situación que implique estrés celular. Es una de las enzimopatías más frecuentes en todo el mundo. El objetivo de este estudio fue determinar la prevalencia de la deficiencia de G6PD en Argentina. Se analizaron 4.500 muestras de sangre seca en varones recién nacidos provenientes de diferentes regiones del país. La actividad de la enzima se determinó cuantitativamente mediante un método fluorométrico semiautomatizado desarrollado en el laboratorio específico para la medición del NADPH producido. El mismo fue evaluado frente a un método comercial. Se hallaron 13 (0,29%) niños que expresaron deficiencia total y 33 (0,73%) deficiencia parcial. Este hallazgo demuestra que la deficiencia de G6PD es una condición frecuente, la detección es factible y no sólo sería útil para la atención especializada contra hemólisis severa en el neonato, sino también para tomar otras medidas preventivas en la edad adulta.(AU)

In Argentina, newborn screening is mandatory by law for certain conditions, but not for Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency. G6PD deficiency is an X chromosome-linked disorder which causes, in most cases, neonatal jaundice, and even kernicterus and acute intravascular hemolysis in association with exposure to oxidizing substances, ingestion of certain foods, drugs or medications, some infections, or any other situation involving cellular stress. It is one of the most common enzymopathies in the world. The aim of this study was to determine the prevalence of G6PDH deficiency in Argentina. A total of 4.500 newborn male dried blood samples from different regions of the country were analyzed. The activity of the enzyme was quantitatively determined by an "in house" developed fluorometric method, measuring the rate of formation of NADPH. It was evaluated against a commercial method. A total of 13 (0.29%) children expressing total deficiency were found, while 33 (0.73%) demonstrated intermediate deficiency. This finding is important as such patients must receive a preventive and educational care. Screening for G6PDH deficiency is feasible and not only would it take early preventive measures against severe hemolysis in the neonatal period, but also other preventive measures later in life.(AU)

Na Argentina, a pesquisa neonatal é obrigatória por lei para determinadas condiþ§es, mas nÒo para a deficiÛncia de glicose-6-fosfato desidrogenase (G6PD). DeficiÛncia de G6PD é um distúrbio ligado ao cromossomo X que pode provocar icterícia neonatal, kernicterus e hemólise intravascular aguda em associaþÒo com a exposiþÒo a substÔncias oxidantes, a ingestÒo de certos alimentos, drogas ou medicamentos, algumas infecþ§es, ou qualquer outra situaþÒo que envolva estresse celular. E uma das enzimopatias mais frequentes em todo o mundo. O objetivo deste estudo foi determinar a prevalÛncia de deficiÛncia de G6PDH na Argentina. Testamos 4.500 amostras de sangue seco de recém-nascidos do sexo masculino originários de diferentes regi§es do país. A atividade da enzima foi determinada quantitativamente através de um método fluorimétrico semi-automatizado desenvolvido no laboratório específico para medir o NADPH produzido. O mesmo foi avaliado perante um método comercial. Acharam-se 13 (0,29%) crianþas expressando deficiÛncia total, enquanto que 33 (0,73%) demonstraram deficiÛncia parcial. Este achado demonstra que a deficiÛncia de G6PD é uma condiþÒo frequente, sua detecþÒo é factível e nÒo só seria útil para o atendimento especializado contra hemólise severa no neonato, mas também para tomar outras medidas preventivas na idade adulta.(AU)