Glucose-6-Phosphate dehydrogenase deficiency in children from 0 to 14 years hospitalized at the Pediatric Hospital David Bernardino, Luanda, Angola

The Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common enzymatic defect in the world. The most common clinical manifestations are acute hemolytic anemia associated with drugs, infections, neonatal jaundice and hemolytic non-spherocytic chronic anemia. The main aim of this study was to determine the frequency of major genetic variants of G6PD leading to enzyme deficiency in children from 0 to 14 years at a Pediatric Hospital in Luanda, Angola. A cross-sectional and descriptive analytical study covered a total of 194 children aged from 0 to 14 years, of both genders and hospitalized at the Pediatric Hospital David Bernardino, Luanda between November and December, 2011. The G202A, A376G and C563T mutations of the G6PD gene were determined by real-time PCR with Taqman probes. The disabled A-/A- genotype was detected in 10 girls (10.9%). Among the boys, 21 (20.6%) presented the genotype A-. Considering all the samples, the A- variant was observed in 22.4% of cases. The Mediterranean mutation was not detected in the Angolan sample. Furthermore, no association was found between genotype and anemia, nutritional state and mucosa color. A significant association, however, was observed with jaundice. Based on the results obtained, there is a clear need to identify those with the disabled genotype in the Angolan population in order to avoid cases of drug-induced anemia, particularly in the treatment of malaria, so prevalent in Angola

Newborn screening of hemoglobinopathies in Bengo, Angola

Sickle cell anemia (SCA) is caused by the presence of the sickle cell allele-HBB*S, in homozygosity. In sub-Saharan Africa, HBB*S typically reaches high frequencies, especially in regions where malaria is endemic. Epidemiologic evidence indicates that the burden of SCA, which currently represents a dramatic public health concern in sub-Saharan Africa, will predictably increase in the future. In this sense, the determination of prevalence, as well as markers of disease severity, are necessary so that the Ministry of Health can develop correct programs to manage the disease. The aim of the study: The objective of this work was to screen by direct sequencing of the HBB gene in a sample of newborns from Bengo, Angola. Moreover, we aim to identify common haplotypes of SCA by Multiplex SNaPshot system.info:eu-repo/semantics/publishedVersio

Newborn screening of hemoglobinopathies in Bengo, Angola

Sickle cell anemia (SCA) is caused by the presence of the sickle cell allele-HBB*S, in homozygosity. In sub-Saharan Africa, HBB*S typically reaches high frequencies, especially in regions where malaria is endemic. Epidemiologic evidence indicates that the burden of SCA, which currently represents a dramatic public health concern in sub-Saharan Africa, will predictably increase in the future. In this sense, the determination of prevalence, as well as markers of disease severity, are necessary so that the Ministry of Health can develop correct programs to manage the disease. The aim of the study: The objective of this work was to screen by direct sequencing of the HBB gene in a sample of newborns from Bengo, Angola. Moreover, we aim to identify common haplotypes of SCA by Multiplex SNaPshot system.info:eu-repo/semantics/publishedVersio

Resultados preliminares do rastreio neonatal de doenças das células falciformes no Hospital Geral do Bengo, Caxito, Angola

As Hemoglobinopatias são doenças hereditárias com uma prevalência de 10 a 30% de portadores na população africana. As alterações das hemoglobinas envolvem a síntese estrutural e quantitativa dos aminoácidos que compõem as diferentes cadeias de globinas. A Doença das Células Falciformes compreende um grupo de hemoglobinopatias que apresentam um conjunto de sinais e sintomas, sendo a forma mais grave da doença. Dada a importância do tema e a escassez de dados no Caxito, Angola, iniciou-se o rastreio Neonatal de Doenças das Células Falciformes no Hospital Geral do Bengo (HGB), onde se localiza o CISA (Centro de Investigação em Saúde de Angola). Objetivos: - Determinar a frequência de recém-nascidos normais (AA), portadores (AS) e patológicos (SS); - Calcular os valores médios dos índices hematrimétricos por classe fenótipica

Epidemiologia das hemoglobinopatias: variabilidade genética da hemoglobina e de enzimas eritrocitárias no Hospital Provincial do Bengo, Caxito, Angola

As hemoglobinopatias são doenças hereditárias resultado de alterações na síntese de cadeias de globina e incluem alterações estruturais e talassemias que são provocadas pela produção diminuída de globina. Se não for diagnosticada e tratada, muitas das hemoglobinopatias resultam em morte nos primeiros anos de vida. Dada a importância do tema e a escassez de dados no nosso meio iniciou-se o estudo das mesmas no Hospital Provincial do Bengo (HGB)

The impact of the ABO/Rh blood group on susceptibility and severity among COVID-19 patients in Luanda, Angola

SARS-CoV-2 is a public health concern worldwide. Identification of biological factors that could influence transmission and worsen the disease has been the subject of extensive investigation. Herein, we investigate the impact of the ABO/Rh blood group on susceptibility and severity among COVID-19 patients in Luanda, Angola. This was a multicentric cohort study conducted with 101 COVID-19 patients. Chi-square and logistic regression were calculated to check factors related to the worsening of the disease and deemed significant when p<0.05. Blood type O (51.5%) and Rh-positive (93.1%) were the most frequent. Patients from blood type O had a high risk to severe disease [OR: 1.33 (95% CI: 0.42 - 4.18), p=0.630] and hospitalization [OR: 2.59 (95% CI: 0.84 - 8.00), p=0.099]. Also, Rh-positive blood type presented a high risk for severe disease (OR: 10.6, p=0.007) and hospitalization (OR: 6.04, p=0.026). We find a high susceptibility, severity, hospitalization, and mortality, respectively, among blood group O and Rh-positive patients, while blood group AB presented a low susceptibility, severity, hospitalization, and mortality, respectively. Our findings add to the body of evidence suggesting that ABO/Rh blood groups play an important role in the course of SARS-CoV-2 infection.info:eu-repo/semantics/publishedVersio

Malaria in children and G6PD deficiency in an endemic area for malaria in Bengo province, Angola

Glucose 6-phosphate dehydrogenase (G6PD) is the rate-limiting enzyme of the pentose phosphate pathway, important in the protection of cells against oxidative stress. The G6PD deficiency is the most common enzymopathy X linked worldwide. The majority of the G6PD deficient do not manifest any symptoms, however, acute hemolytic anemia may be trigger by several agents, such as primaquine. Current WHO guidelines state that in elimination areas a single 0.25 mg base/kg primaquine dose should be given, as a gametocytocide, to all patients with parasitological-confirmed P. falciparum malaria on the first day of treatment in addition to an ACT. In face of this recommendation, endemic malaria countries should be informed of the prevalence of G6PD deficiency, in order to make safe and appropriate decisions regarding the use of potentially unsafe drugs for G6PD deficient individuals. Objectives: The aim of this study is to determine the prevalence of G6PD deficiency in a holoendemic region in Africa for P falciparum, evaluating the genotype and the phenotype of the enzyme.info:eu-repo/semantics/publishedVersio

Protection against malaria in heterozygous girls for G6PD deficiency in Angola

G6PD deficiency has become more prevalent in malaria-endemic regions because genetic variants can confer protection against Plasmodium. However, these conclusions are still in debate. The aim of this work is to evaluate the prevalence of G6PD deficiency in an African holoendemic region for Plasmodium falciparum, estimating the genotype and phenotype of the enzyme, and evaluating the risk of malaria associated with the G6PD genotype. A prospective longitudinal cohort study, involving 1692 children selected in the maternity ward and monitored over quarterly medical consultations for two years. The G202A and A376G genotypes were determined through Real-Time PCR methods. For enzyme activity, we applied the NeoLISA kit for Neonatal G6PD deficiency screening to measure the NADPH produced calorimetrically in the kinetic model. The prevalence of the A-allele was 19.4%, with 19% hemizygous boys and 4.5% A-homozygous girls. Enzyme deficiency, measured by enzyme activity, was highly prevalent (32.7% in males and 30.5% in females). The average enzymatic activity was also low for A-hemizygous boys (1.66U/gHb) and for homozygous girls (0. 97U/gHb). Heterozygous girls would seem to hold some protection against malaria when compared to the other genotypes, mainly A-/A- (X2=14.35, p=0.014). The prevalence of G6PD deficiency among children in Bengo is high. Heterozygous girls, as proposed elsewhere, maybe the driving force for positive selection. This data may serve the ministry of health in taking safe and appropriate decisions regarding the usage of potentially unsafe drugs for G6PD deficient individuals.info:eu-repo/semantics/publishedVersio

Unusual β-globin haplotype distribution in newborns from Bengo, Angola

COMPETE 2020. POCI-01-0145-FEDER-007274 to i3S.Mutations on the HBB gene are a common cause of hemoglobinopathies, including sickle cell anemia, a severe genetic condition that constitutes a major public health concern. The aim of this study was to determine the prevalence of sickle cell anemia and β-globin haplotype distribution in newborns from the Bengo region. The first two exons of β-globin gene were sequenced, and the variability at the single nucleotide polymorphism (SNP) defining the Hb S (HBB: c.20A>T) haplotypes, was analyzed by a SNaPshot® Multiplex system. About 3.3% of the children were homozygous for Hb S, and 82.2% had as background the Bantu/Central African Republic (BAN/CAR) haplotype, 11.2% the Benin (BEN) and 6.6% the Senegal (SEN). The estimate of Hb S reached the very high value of 0.1476 ± 0.0133, with the aggravating factor of 82.2% of the sickle alleles being anchored in the BAN/CAR haplotype, associated with the more severe sickle cell anemia phenotypes. Also, the high prevalence of the SEN haplotype was not expected, having therapeutic consequences since is associated with more severe outcomes. In addition, two β-thalassemia (β-thal) variants were also detected, IVS I-110 (G>A) (HBB: c.93-21G>A) and codon 39 (C>T) (HBB: c.118C>T), together totaling a frequency of 1.3%. Some of the newborns with these mutations were compound heterozygotes for Hb S, likely carrying genotypes consistent with sickle cell disease. As a whole, infants molecularly diagnosed with sickle cell disease accounted for 4.5% of newborns from Bengo, Angola, a figure that per se, highlights the urgent need of implementing policies warranting surveillance of these children, in parallel with community education in the region.info:eu-repo/semantics/publishedVersio