Sickle Cell Anaemia Prevalence among Newborns in the Brazilian Amazon-Savanna Transition Region
Sickle cell anaemia is one of the most common hemoglobinopathies worldwide and an important public health problem in Brazil. This study evaluated the prevalence of sickle cell anaemia and its traits in newborns from the Amazon-Savanna Transition Region in the state of Maranhão, Brazil. A cross-sectional study was carried out, based on data from neonatal screening tests performed in 2013–2015 in Maranhão. The Hardy-Weinberg theorem was applied to analyse the frequency of expected homozygotes based on HbSS phenotype. A spatial-temporal distribution analysis was performed to delimit the regions with the greatest number of newborn cases with sickle cell anaemia. Of 283,003 newborns, 162 were found to have sickle cell anaemia, while 10,794 had a sickle cell trait, with a prevalence of 0.05% and 3.8%, respectively. The prevalence of expected homozygotes was higher in the North Region and in the state capital of Maranhão. This study may contribute to existing social and public health actions or the creation of new strategies for sickle cell disease in endemic areas in Brazil to improve the quality of life.
Diagnóstico laboratorial da doença falciforme em neonatos e após o sexto mês de vida
Sickle Cell disease (SCD) is a genetic disorder of the hemoglobin, with high prevalence in Brazil. It presents high morbidity and mortality with early identification and treatment being necessary. The recognition of this situation has made the diagnosis of SCD mandatory through neonatal screening in Brazil. SCD Laboratorial diagnosis in the neonate is based on the detection of S hemoglobin, in preference, using IEF and/or HPLC techniques, which present high sensitivity and specificity. These methods also allow the detection of carriers traits and other variant hemoglobins. The main phenotypic possibilities on SCD at birth are: Hb FS, Hb FSC, Hb FSA and Hb FSD-Punjab. The child should be referred for medical assessment independent of the phenotype found and the examination being repeated after six months of life to confirm of the hemoglobinic profile. Other complementary examinations may be necessary for differential diagnoses of the different forms of the disease, such as the measurement of Hb A2 and Fetal Hb, as well as a study of the family history.
Freqüência dos antígenos HLA- A e HLA- B em populações das regiões de Curitiba e Norte/Noroeste do Estado do Paraná
HLA- A and HLA- B antigens are glycoproteins expressed on the surfaces of nuclear cells and responsible for presenting different antigens to T lymphocytes, during immune response. They are codified by the Major Histocompatibility Complex genes and are characterized by their high polymorphism. The HLA polymorphism level varies in different populations and ethnic groups. The Brazilian population is a result of significant racial admixture. In this paper, the antigen, gene and haplotype frequencies of HLA-A and B were analyzed in healthy and unrelated white individuals living in Curitiba and northern region of Parana, Brazil. The HLA distribution was compared between the two groups. The HLA antigens were typed by microlymphocytotoxicity method. The predominance of the Caucasian component was observed in the distribution of HLA, however the racial admixture showed to be more significant in the northern region