Sickle Cell Disease in Brazil: Current Management.

Sickle cell disease (SCD) comprises inherited red blood cell disorders due to a mutation in the ß-globin gene (c20A > T, pGlu6Val) and is characterized by the presence of abnormal hemoglobin, hemoglobin S, hemolysis, and vaso-occlusion. This mutation, either in a homozygous configuration or in compound states with other ß-globin mutations, leads to polymerization of hemoglobin S in deoxygenated conditions, causing modifications in red blood cell shape, particularly sickling. Vaso-occlusive crisis (VOC) is the hallmark of the disease, but other severe complications may arise from repeated bouts of VOCs. SCD is considered a global health problem, and its incidence has increased in some areas of the world, particularly the Americas and Africa. Management of the disease varies according to the region of the world, mainly due to local resources and socioeconomic status. This review aimed to describe more recent data on SCD regarding available treatment options, especially in Brazil. New treatment options are expected to be available to all patients, particularly crizanlizumab, which is already approved in the country.

Consensus of the Brazilian Association of Hematology, Hemotherapy and Cellular Therapy (ABHH) and the Brazilian Ministry of Health - General management of blood and blood products on the tests necessary for the release of exceptional medicines for sickle cell disease.

To date, hydroxyurea is the only effective and safe drug that significantly reduces morbidity and mortality of individuals with Sickle cell disease. Twenty years of real-life experience has demonstrated that hydroxyurea reduces pain attacks, vaso-occlusive events, including acute chest syndrome, the number and duration of hospitalizations and the need for transfusion. The therapeutic success of hydroxyurea is directly linked to access to the drug, the dose used and adherence to treatment which, in part, is correlated to the availability of hydroxyurea. This consensus aims to reduce the number of mandatory exams needed to access the drug, prioritizing the requesting physician's report, without affecting patient safety.

Real-world evidence of the burden of sickle cell disease: a 5-year longitudinal study at a Brazilian reference center.

INTRODUCTION: Sickle cell disease (SCD) is an inherited and multisystem blood disorder characterized by hemolytic anemia, vaso-occlusive crises (VOCs), progressive multiorgan damage and increased mortality. In Brazil, it is one of the most common monogenic diseases afflicting 60,000 to 100,000 individuals, however, there are sparse epidemiological data, as well as information on the utilization of public healthcare resources. METHOD: This was a 5-year (2016 - 2020) retrospective study conducted at one Brazilian reference center on SCD - Santa Casa de Sao Paulo, in Sao Paulo, Brazil. RESULTS: Among a total of 100 eligible adult patients, the median age was 31.0 years old, 84% of the patients were aged between 18 and 45 years old; 59% were women and 91% presented the genotype HbSS. The number of hematologist and non-hematologist visits at the outpatient unit were 2,198 and 1,436, respectively. The number of hospital ER visits was 758, of which 51% required 864 days of hospitalization. The main cause for seeking hospital medical care was the VOCs. The numbers and ratios of VOCs were: 1 to 10 VOCs, 64%; 11 to 20, 15%, and; 21 or more, 1%. There was a statistically significant difference between the number of VOCs and hospitalizations, as well as infection. CONCLUSION: Results indicate the burden of SCD on Brazilian patients' daily lives, the impact of VOCs on public healthcare resources, the importance of having a national surveillance program to improve resource utilization and clinical outcomes of patients with SCD and the urgent need for the revitalizing of the current national comprehensive SCD care programs.

Novel Insights into the Pathophysiology and Treatment of Sickle Cell Disease.

The polymerization of hemoglobin under deoxygenation is the main pathophysiological event in sickle cell diseases, described more than 70 years ago. The last two decades have seen a major increase in knowledge about the cascade of events that follow the polymerization of hemoglobin and the ensuing sickling of red blood cells. Several distinctive therapeutic targets have been discovered as a result, and a few drugs with innovative mechanisms of action are already on the market, while several others are the focus of ongoing trials. The aim of this narrative review is to describe some of the more recent data in the SCD literature regarding pathophysiology and novel treatments.

Estimated mortality rates of individuals with sickle cell disease in Brazil: real-world evidence.

Sickle cell disease (SCD) is a group of hereditary chronic diseases with a substantial impact on quality of life and morbimortality. In Brazil, it is 1 of the most common hereditary diseases; however, there are sparse epidemiological data for the country. Using data from death certificates, we aimed to estimate the median age at death, years of life lost because of SCD, and the median survival. From 2015 to 2019, we identified 3320 records of deaths of individuals with SCD, from a total of 6 553 132 death records. Among individuals with SCD, the median age at death was 37 years less than that of the general population (SCD: aged 32.0 years at death, interquartile range [IQR], 19.0-46.0; general population: aged 69.0 years at death; IQR, 53.0-81.0). Results were consistent when stratified by sex or race. Over the 5 years evaluated, crude death rates varied from 0.30 to 0.34 per 100 000 inhabitants (mean 0.32 per 100 000 inhabitants). We estimated a prevalence of 60 017 individuals living with SCD (29.02 cases per 100 000) and an average incidence of 1362 cases yearly. The median estimated survival was 40 years for individuals with SCD and 80 years for the general population. SCD was associated with an increased risk of mortality in most age ranges. Among individuals with SCD aged between 1 and 9 years and between 10 and 39 years, the risk of death was 32 and 13 times higher, respectively. The most common causes of death were sepsis and respiratory failure. These results highlight the burden of SCD in Brazil and the necessity of improved care for this population.

Brazilian family with hyperferritinemia-cataract syndrome: case report.

Hereditary hyperferritinemia-cataract syndrome is a rare autosomal dominant disease caused by a genetic mutation in the iron responsive element in the 5' untranslated region of the ferritin light chain gene. Hereditary hyperferritinemia-cataract syndrome is characterized by elevated serum ferritin levels and bilateral cataract development early in life and may be misdiagnosed as hemochromatosis. This case report describes a Brazilian family with a clinical diagnosis of hereditary hyperferritinemia-cataract syndrome, which was submitted to ferritin light chain gene sequencing. The genetic mutation c.-164C>G was identified in the 5' untranslated region. In conclusion, genetic testing can be used for accurate diagnosis of hereditary hyperferritinemia-cataract syndrome to avoid misdiagnosis of hemochromatosis, other diseases associated with iron overload or ophthalmic diseases.

Quality of Life Scores Remained Different among the Genotypic Groups of Patients with Suspected Hemochromatosis, Even after Treatment Period.

BACKGROUND: Hemochromatosis is a genetic condition of iron overload caused by deficiency of hepcidin. In a previous stage of this study, patients with suspected hemochromatosis had their quality of life (QL) measured. We observed that QL scores differed among genotypic groups of patients. In this reported final phase of the study, the aims were to compare QL scores after a treatment period of approximately 3 years and to analyze a possible association of the serum ferritin values with QL scores. METHODS: Sixty-five patients were enrolled in this final phase and divided into group 1 (patients that showed primary iron overload and homozygous genotype for the HFE p.Cys282Tyr mutation) and group 2 (other kinds of genotypes). Short Form 36 (SF-36) was performed and consisted of eight domains with a physical and also a mental component. RESULTS: Both groups had a significant decrease in serum ferritin concentrations: group 1 had a variation from 1844 ± 1313 ng/mL to 281 ± 294 ng/mL, and group 2 had a variation from 1216 ± 631 ng/mL to 236 ± 174 ng/mL. Group 1 had a smaller mean value for these six SF-36 domains compared with group 2, indicating a worse QL. CONCLUSIONS: In this final stage, six domains demonstrated a difference among genotypic groups (role emotional and mental health, adding to the four of the initial phase), reassuring the impact of the identified genotype on the QL of hemochromatosis patients. Furthermore, despite that both patient groups demonstrated similar and significant decreases in serum ferritin values, no association was found between the decrease in this biological parameter and the SF-36 domains.

Brazilian family with hyperferritinemia-cataract syndrome: case report

ABSTRACT Hereditary hyperferritinemia-cataract syndrome is a rare autosomal dominant disease caused by a genetic mutation in the iron responsive element in the 5' untranslated region of the ferritin light chain gene. Hereditary hyperferritinemia-cataract syndrome is characterized by elevated serum ferritin levels and bilateral cataract development early in life and may be misdiagnosed as hemochromatosis. This case report describes a Brazilian family with a clinical diagnosis of hereditary hyperferritinemia-cataract syndrome, which was submitted to ferritin light chain gene sequencing. The genetic mutation c.-164C>G was identified in the 5' untranslated region. In conclusion, genetic testing can be used for accurate diagnosis of hereditary hyperferritinemia-cataract syndrome to avoid misdiagnosis of hemochromatosis, other diseases associated with iron overload or ophthalmic diseases.

Novel mutations in the bone morphogenetic protein 6 gene in patients with iron overload and non-homozygous genotype for the HFE p.Cys282Tyr mutation.

BACKGROUND: Five main genes are associated with hemochromatosis; however, current studies show that, in addition to these genes, others may be associated with primary iron overload (IO). One of these is the bone morphogenetic protein 6 (BMP6), which encodes a protein that modulates hepcidin synthesis and, consequently, iron homeostasis. AIM: To identify BMP6 gene pathogenic variants in patients with IO and non-homozygous genotype for the HFE p.Cys282Tyr mutation. MATERIALS AND METHODS: Fifty-three patients with primary IO and non-homozygous genotype for the HFE p.Cys282Tyr were selected. Subsequent bidirectional DNA sequencing of BMP6 exons was performed. RESULTS: Two novel variants were found. One at homozygous state p.Gln158Ter (c.472C>T) was pathogenic, the other one at heterozygous state p.Val394Met (c.1180G>A) was of uncertain significance (VUS); the third variant at heterozygous state p.Arg257His (c.770G>A) has already been described and associated with IO. No BMP6 pathogenic variants that would explain iron overload phenotypes were detected in 94% of the studied patients. CONCLUSION: Identification of the BMP6 pathogenic variants in Brazilian patients with primary IO might contribute to the genetic understanding of this phenotype.

Daily supplementation with 5 mg of folic acid in Brazilian patients with hereditary spherocytosis.

Patients with hereditary spherocytosis (HS) have increased rates of erythropoiesis and higher folate requirements. In a case-control study of patients with HS, we evaluated the associations between the use of 5 mg folic acid (FA) daily and serum concentrations of folate, unmetabolized folic acid (UMFA), interleukin (IL)-6, IL-8, IL-10, interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α); and mRNA expression of dihydrofolate reductase (DHFR), methylene tetrahydrofolate reductase (MTHFR), IL8, IFNG and TNFA genes. Total serum folate and folate forms were measured in 27 patients with HS (21 users [HS-U] and 6 non-users [HS-NU] of supplemental FA) and 54 healthy controls not consuming 5 mg/day supplemental FA. Each patient was matched to two controls based on age, sex and body mass index. The mononuclear leucocyte mRNA expression of relevant genes and their products were determined. Serum folate, UMFA, 5-methyl-tetrahydrofolate (5-methyl-THF) and tetrahydrofolate (THF) concentrations were significantly higher in HS-U compared with matched healthy controls (p<0.001, n=42). HS-NU had lower serum folate concentrations than matched healthy controls (p=0.044, n=12). HS-U and HS-NU presented similar hematological and biochemical markers profiles. No differences were found between HS-U and HS-NU for cytokine serum concentrations and mRNA expression genes. DHFR mRNA expression was higher in HS-U than in HS-NU. The use of high daily doses of FA for treatment of patients with HS may be excessive and is associated with elevated serum UMFA and elevated DHFR mRNA expression. It is not known whether long-term high-dose FA use by patients with HS might have adverse health effects.

Quality of life scores differs between genotypic groups of patients with suspected hereditary hemochromatosis.

BACKGROUND: Hereditary hemochromatosis (HH) encompasses a group of autosomal recessive disorders mainly characterized by enhanced intestinal absorption of iron and its accumulation in parenchymal organs. HH diagnosis is based on iron biochemical and magnetic resonance imaging (MRI) assessment, and genetic testing. Questionnaires, such as SF-36 (short form health survey), have been increasingly used to assess the impact of diseases on the patient's quality of life (QL). In addition, different genotypes are identified as results of genetic tests in patients with suspected primary iron overload. In the present study, our aim was to evaluate whether domains of QL are different according to genotypic groups in patients suspected of HH. METHODS: Seventy-nine patients with primary iron overload were included and two genotypic groups were formed (group 1: homozygous genotype for the HFE p.Cys282Tyr mutation; group 2: other genotypes). RESULTS: Group 1 had higher means of plasma transferrin saturation (86 ± 19%) and serum ferritin (1669 ± 1209 ng/mL) compared to group 2 (71 ± 12%, 1252 ± 750 ng/mL, respectively; p = 0.001). Four domains were significantly different among groups 1 and 2: physical functioning (p = 0.03), bodily pain (p = 0.03), vitality (p = 0.02) and social functioning (p = 0.01). CONCLUSIONS: Our main finding was that patients with p.Cys282Tyr homozygosity had a worse QL scenario assessed by SF-36, compared with patients with iron overload without the same genotype. Being aware of this relationship between genotypes and QL might be helpful in the overall management of patients suspected of hereditary hemochromatosis.