ABSTRACT Introduction: Scientometrics is the field concerned with measuring and analyzing academic literature, using specific metrics and data from bibliometric databases. Hematology is a broad area of science and medicine, from which several landmark scientific discoveries have emerged. Objective: The aim of this report is to provide a snapshot of the landscape of hematology research in Brazil, based on a comprehensive analysis of published studies in hematology whose authors were affiliated to Brazilian institutions from 1980 to 2020. Method: Articles, reviews and letters to the editor with at least one author affiliated to a Brazilian institution were retrieved from Incytes/Web of Science or Scopus databases. Importantly, only papers classified in the subject area “Hematology” by the embedded algorithms of each database were included. Results: Considering all published papers, Brazil is in the 22nd position, contributing with around 1.1% of papers in this period. A clear and sustained increase in publication output can be observed from the early 1990’s to the present moment. Publicly-funded higher education institutions were the main contributors to the development and consolidation of the hematology scientific community, which has grown in diversity, with an increasing number of contributions from private institutions. In regard to funding, public agencies have been and remain by large as the most important funder of research in hematology in Brazil. Conclusion: We suggest that continuous monitoring of the temporal trends of some of the data compiled in our report could potentially contribute to a clearer picture of the development of hematology research in Brazil.

Paroxysmal nocturnal hemoglobinuria is a chronic, multi-systemic, progressive and lifethreatening disease characterized by intravascular hemolysis, thrombotic events, serious infections and bone marrow failure. Paroxysmal nocturnal hemoglobinuria results from the expansion of a clone of hematopoietic cells that due to an inactivating mutation of the X-linked gene PIG-A are deficient in glycosylphosphatidylinositol-linked proteins. Early diagnosis, using flow cytometry performed on peripheral blood, the gold standard test to confirm the diagnosis of paroxysmal nocturnal hemoglobinuria, is essential for improved patient management and prognosis. The traditional therapy for paroxysmal nocturnal hemoglobinuria includes blood transfusion, anti-thrombosis prophylaxis or allogeneic bone marrow transplantation. The treatment that has recently become available is the complement blockade by the anti-C5 monoclonal antibody eculizumab. In this consensus, we are aiming to review the diagnosis and treatment of the paroxysmal nocturnal hemoglobinuria patients, as well as the early recognition of its systemic complications. These procedures express the opinions of experts and have been based on the best available evidence and international guidelines, with the purpose of increasing benefits and reducing harm to patients.

ABSTRACT Objectives and methods: We evaluated possible relationships between echocardiographic findings and clinical and laboratory parameters, in a cohort of Brazilian patients diagnosed with sickle cell/β-thalassemia, to better understand the cardiac involvement in this disease. Results: Left atrial (LA) and left ventricular (LV) dilation were found in 19.5 and 11% of patients, respectively; systolic left ventricular dysfunction was present in a single patient. There were no differences in masses and volumes of cardiac chambers comparing Sβ0 with Sβ+ patients, and no relationship between these parameters and specific complications of the disease. However, parameters of altered ventricular geometry were significantly correlated with serum creatinine, hepatic transaminases and bilirubin levels. Moreover, 3 patients presented stroke; they were significantly older [53 (41-56) × 37.5 (18-70), p = 0.048], had higher values of LV posterior wall diastolic thickness [10 (10-11) × 8 (6-14), p = 0.03], LV mass [226 (194-260) × 147 (69-537), p = 0.039] and LA/aortic ratio [1.545 (1.48-1.61) × 1.26 (0.9-1.48), p = 0.032]. Conclusions: Cardiac involvement in this disease does not appear to depend on the thalassemia phenotype. The presence of signs of myocardial remodeling in this group of patients was related to multi-organ impairment and rendered a higher propensity for stroke in older patients, suggesting the need for greater vigilance and control of associated factors.

Abstract Background: Pyruvate kinase deficiency is a hereditary disease that affects the glycolytic pathway of the red blood cell, causing nonspherocytic hemolytic anemia. The disease is transmitted as an autosomal recessive trait and shows a marked variability in clinical expression. This study reports on the molecular characterization of ten Brazilian pyruvate kinase-deficient patients and the genotype–phenotype correlations. Method: Sanger sequencing and in silico analysis were carried out to identify and characterize the genetic mutations. A non-affected group of Brazilian individuals were also screened for the most commonly reported variants (c.1456C>T and c.1529G>A). Results: Ten different variants were identified in the PKLR gene, of which three are reported here for the first time: p.Leu61Gln, p.Ala137Val and p.Ala428Thr. All the three missense variants involve conserved amino acids, providing a rationale for the observed enzyme deficiency. The allelic frequency of c.1456C>T was 0.1% and the 1529G>A variant was not found. Conclusion: This is the first comprehensive report on molecular characterization of pyruvate kinase deficiency from South America. The results allowed us to correlate the severity of the clinical phenotype with the identified variants.

Background: Brazil has a multiethnic population with a high diversity of hemoglobinopathies. While screenings for beta-globin mutations are far more common, alterations affecting alpha-globin genes are usually more silent and less well known. The aim of this study was to describe the results of a screening program for alpha-globin gene mutations in a representative sample of the Southeastern Brazilian population. Methods: A total of 135,000 individuals, including patients with clinical suspicion of hemoglobinopathies and their family members, randomly chosen individuals submitted to blood tests and blood donors who were abnormal hemoglobin carriers were analyzed. The variants were screened by alkaline and acid electrophoreses, isoelectric focusing and cation-exchange high performance liquid chromatography (HPLC) and the abnormal chains were investigated by reverse-phase high performance liquid chromatography (RP-HPLC). Mutations were identified by molecular analyses, and the oxygen affinity, heme-heme cooperativity and Bohr effect of the variants were evaluated by functional tests. Results: Four new and 22 rare variants were detected in 98 families. Some of these variants were found in co-inheritance with other hemoglobinopathies. Of the rare hemoglobins, Hasharon, Stanleyville II and J-Rovigo were the most common, the first two being S-like and associated with alpha-thalassemia. Conclusion: The variability of alpha-globin alterations reflects the high degree of racial miscegenation and an intense internal migratory flow between different Brazilian regions. This diversity highlights the importance of programs for diagnosing hemoglobinopathies and preventing combinations that may lead to important clinical manifestations in multiethnic populations.

Relatar um caso de sobrecarga de ferro secundária à xerocitose, uma doença rara, em uma adolescente, diagnosticada por meio de ressonância magnética em T2*. Relatamos o caso de uma paciente sintomática com xerocitose, nível de ferritina de 350ng/mL e sobrecarga de ferro cardíaca significativa. Ela foi diagnosticada por ressonância magnética em T2* e recebeu terapia de quelação. Análise por ectacitometria confirmou o diagnóstico de xerocitose hereditária. Na sequência, a ressonância magnética em T2* demonstrou resolução completa da sobrecarga de ferro em vários órgãos e novo ecocardiograma revelou resolução completa das alterações cardíacas anteriores. A paciente permanece em terapia de quelação. Xerocitose é uma desordem genética autossômica dominante rara, caracterizada por estomatocitose desidratada. O paciente pode apresentar fadiga intensa e sobrecarga de ferro. Sugerimos o uso regular de ressonância magnética em T2* para o diagnóstico e controle da resposta à quelação de ferro em xerocitose e acreditamos que o exame pode ser útil também em outras anemias hemolíticas que necessitam de transfusões.

To report a case of iron overload secondary to xerocytosis, a rare disease in a teenager, diagnosed, by T2* magnetic resonance imaging. We report the case of a symptomatic patient with xerocytosis, a ferritin level of 350ng/mL and a significant cardiac iron overload. She was diagnosed by T2* magnetic resonance imaging and received chelation therapy Ektacytometric analysis confirmed the diagnosis of hereditary xerocytosis. Subsequent T2* magnetic resonance imaging demonstrated complete resolution of the iron overload in various organs, as a new echocardiography revealed a complete resolution of previous cardiac alterations. The patient remains in chelation therapy. Xerocytosis is a rare autosomal dominant genetic disorder characterized by dehydrated stomatocytosis. The patient may present with intense fatigue and iron overload. We suggest the regular use of T2* magnetic resonance imaging for the diagnosis and control of the response to iron chelation in xerocytosis, and we believe it can be used also in other hemolytic anemia requiring transfusions.

Hemoglobinopathies are the most common recessive diseases worldwide but their prevalence in Uruguay has not been investigated. In this study, 397 unrelated outpatient children from the Pereira Rosell Hospital Center (CHPR), as well as 31 selected patients with microcytic anemia and 28 β-thalassemia carriers were analyzed for hemoglobinopathies by using biochemical and molecular biology methods. Parametric and non-parametric methods were used to compare the hematological indices between groups of genotypes. Of the 397 patients in the first group, approximately 1% (0.76% HbS and 0.25% β-thalassemia) had a mutation in the HBB gene and 3.3% had α-thalassemia. These mutations had a heterogeneous distribution that varied according to individual ancestry. HbS was found exclusively in individuals with declared African ancestry and had a carrier frequency of 2.2%. The frequency of α-thalassemia carriers in outpatients of European and African ancestry was 1.2% and 6.5%, respectively. In contrast, the frequency of α-thalassemia carriers in patients with microcytic anemia was 25.8%, significantly higher (p < 0.01) than that observed in the sample as a whole and in Afro-descendants and Euro-descendants. Significant differences were observed in the hematological parameters between individuals with thalassemia genotypes and those with a normal genotype. These results indicate that hemoglobinopathies are a relevant health problem in Uruguay.

Hemoglobin Southampton (also known as hemoglobin Casper) is a rare hemoglobin structural variant resulting from a substitution of a leucine residue for proline at codon beta106 [beta106(G8)Leu→Pro, CTG→CCG]. It is very unstable and associated with severe hemolytic anemia. We detected this mutation in a 37-year-old Uruguayan woman with a history of severe chronic hemolytic anemia since her childhood. According to our knowledge this is the first time that this variant has been found in the Uruguayan population.

α-Thalassemia, arising from a defect in a-globin chain synthesis, is often caused by deletions involving one or both of the a-genes on the same allele. With the aim of investigating the prevalence of α-thalassemia 3.7 kb deletion in the adult population of Rio Grande do Norte, 713 unrelated individuals, between 18 and 59 years-of-age, were analyzed. Red blood cell indices were electronically determined, and A2 and F hemoglobins evaluated by HPLC. PCR was applied to the molecular investigation of α-thalassemia 3.7 kb deletion. Eighty (11.2%) of the 713 individuals investigated presented α-thalassemia, of which 79 (11.1%) were heterozygous (-α3.7/αα) deletions and 1 (0.1%) homozy- gous (-α3.7/-α3.7). Ethnically, heterozygous deletions were higher (24.8%) in Afro-Brazilians. Comparison of hemato- logical parameters between individuals with normal genotype and those with heterozygous α+-thalassemia showed a statistically significant difference in the number of erythrocytes (p < 0.001), MCV (p < 0.001), MCH (p < 0.001) and Hb A2 (p = 0.007). This study is one of the first dedicated to investigating α-thalassemia 3.7 kb deletion in the population of the State Rio Grande do Norte state. Results obtained demonstrate the importance of investigating this condition in order to elucidate the causes of microcytosis and hypochromia.