CONTEXT AND OBJECTIVES: Sickle cell disease (SCD) is the most common genetic disorder among people of African descent, affecting approximately 3,500 newborns each year in Brazil. Hydroxyurea (HU) is the only effective drug to treating patients with SCD, thereby reducing morbidity and mortality. The objective was to analyze the effects of HU on SCD patients at our institution. DESIGN AND SETTING:Retrospective study conducted at a sickle cell centre in Ribeirão Preto, São Paulo, Brazil. METHODS:We analyzed clinical and laboratory data on 37 patients. The hematological parameters and clinical events that occurred during the year before and the first year of treatment with HU were analyzed. The mean dose of HU was 24.5 ± 5.5 mg/kg/day. RESULTS: There were rises in three parameters: hemoglobin (8.3 g/dl to 9.0 g/dl, P = 0.0003), fetal hemoglobin (HbF) (2.6% to 19.8%, P < 0.0001) and mean cell volume MCV (89 to 105 fl, P = 0.001); and reductions in the numbers of leukocytes (10,050/µl to 5,700/µl, P < 0.0001), neutrophils (6,200/µl to 3,400/µl, P = 0.001), platelets (459,000/µl to 373,000/µl, P = 0.0002), painful crises (1.86 to 0.81, P = 0.0014), acute chest syndromes (0.35 to 0.08, P = 0.0045), infections (1.03 to 0.5, P = 0.047), hospitalizations (1.63 to 0.53, P = 0.0013) and transfusions (1.23 to 0.1, P = 0.0051). CONCLUSION:The patients presented clinical and hematological improvements, with an increase in HbF and a reduction in the infection rate, which had not been addressed in most previous studies. RESUMO CONTEXTO E OBJETIVO:A doença falciforme (SCD) é o distúrbio genético mais comum entre afrodescendentes, afetando aproximadamente 3.500 recém-nascidos a cada ano no Brasil. A hidroxiureia (HU) é a única droga efetiva para o tratamento dos pacientes com SCD, reduzindo a morbidade e a mortalidade da doença. O objetivo do estudo foi analisar os efeitos da HU em pacientes com SCD em nossa instituição. TIPO DE ESTUDO E LOCAL: Estudo retrospectivo realizado em um centro de anemia falciforme em Ribeirão Preto, São Paulo, Brasil. MÉTODOS: Nós analisamos os dados clínicos e laboratoriais de 37 pacientes. Os parâmetros hematoló-gicos e eventos clínicos que ocorreram no ano anterior e durante o primeiro ano de tratamento com HU foram analisados. A dose média de HU foi 24.5 ± 5.5 mg/kg/dia. RESULTADOS: Houve aumento em três parâmetros estudados: hemoglobina (8,3 g/dl para 9,0 g/dl, P = 0,0003), hemoglobina fetal (HbF) (2,6% para 19,8%, P < 0,0001) e volume corpuscular médio (VCM) (89 para 105 fl, P = 0,001); e redução do número de leucócitos (10.050/µl para 5.700/µl, P < 0,0001), neutrófi-los (6.200/µl para 3.400/µl, P = 0,001), plaquetas (459.000/µl para 373.000/µl, P = 0,0002), crises dolorosas (1,86 para 0,81, P = 0,0014), síndrome torácica aguda (0,35 para 0,08, P = 0,0045), infecções (1,03 para 0,5, P = 0,047), hospitalizações (1,63 para 0,53, P = 0,0013) e número de transfusões (1,23 para 0,1, P = 0,0051). CONCLUSÃO: Os pacientes apresentaram melhora clínica e hematológica, com aumento da HbF e redução da ...
ObjectiveThe objective of this study was to verify the evolution of pregnancies in sickle cell patients followed at one institution over a period of 12 years (January 2000 to June 2012).MethodsThe study evaluated 34 pregnant women with sickle cell disease with a mean age of 23.9 ± 5.3 years. The incidence of obstetric complications, non-obstetric complications linked to sickle cell disease and complications in the newborn were analyzed.ResultsA total of 26% of the cases reported previous miscarriages, 20% had preterm labor, 10% had pre-eclampsia, and 5% had gestational diabetes. Forty-one percent of the deliveries were cesarean sections and 29% of patients required blood transfusions. In respect to sickle cell disease, 62% of patients had vaso-occlusive crises, 29% had acute chest syndrome, 23% had urinary tract infection, 15% had impaired cardiac function and 6% developed pulmonary hypertension. Only one patient died in the postnatal period due to acute chest syndrome. The mean gestational age was 37.8 ± 2.63 weeks, and mean newborn weight was 2.809 ± 643.8 g. There were seven fetal losses, including three stillbirths and four miscarriages. The impact of transfusion therapy on the incidence of maternal–fetal complications during pregnancy was evaluated.ConclusionsPregnancy in sickle cell patients is still associated with complications. Although no statistical difference was observed between transfused and non-transfused women, there were no deaths (fetal or maternal) in transfused patients whereas one maternal death and three stillbirths occurred in non-transfused women. A larger study of sickle cell pregnant women will be necessary to elucidate the actual role of transfusion during pregnancy in sickle cell disease.
The thalassemia syndromes (α- and β-thalassemia) are the most common and frequent disorders associated with ineffective erythropoiesis. Imbalance of α- or β-globin chain production results in impaired red blood cell synthesis, anemia and more erythroid progenitors in the blood stream. While patients affected by these disorders show definitive altered parameters related to erythropoiesis, the relationship between the degree of anemia, altered erythropoiesis and dysfunctional iron metabolism have not been investigated in both α-thalassemia carriers (ATC) and β-thalassemia carriers (BTC). Here we demonstrate that ATC have a significantly reduced hepcidin and increased soluble transferrin receptor levels but relatively normal hematological findings. In contrast, BTC have several hematological parameters significantly different from controls, including increased soluble transferrin receptor and erythropoietin levels. These changings in both groups suggest an altered balance between erythropoiesis and iron metabolism. The index sTfR/log ferrin and (hepcidin/ferritin)/sTfR are respectively increased and reduced relative to controls, proportional to the severity of each thalassemia group. In conclusion, we showed in this study, for the first time in the literature, that thalassemia carriers have altered iron metabolism and erythropoiesis.
Intrahepatic cholestasis (SCIC) is an uncommon but potentially fatal complication of sickle cell disease (SCD), with a high death rate, observed mainly in patients with homozygous sickle cell anemia. Herein, we describe a case of severe SCIC treated successfully with aggressive manual exchange transfusion (ET). The patient was admitted with enlarged liver and signs of hepatic failure, such as hyperbilirubinemia and coagulopathy. There was no evidence of viral hepatitis or biliary obstruction. We performed several sessions of ET in order to reduce the percentage of HbS to levels inferior to 30%, which was successfully accomplished. The patient had a complete recovery of hepatic function. This case has shown that ET is an effective treatment of SCIC and should be introduced early on the onset of this severe complication.
Human Parvovirus B19 (B19V) is a recognized cause of life-threatening conditions among patients with hemoglobinopathies. This study investigates B19V infection in patients with sickle cell disease and β-thalassemia using different experimental approaches. A total of 183 individuals (144 with sickle cell disease and 39 with β-thalassemia major) and 100 healthy blood donors were examined for B19V using anti-B19V IgG enzyme immunoassay, quantitative PCR, DNA sequencing, and phylogenetic analysis. Viremia was documented in 18.6% of patients and 1% of donors, and was generally characterized by low viral load (VL); however, acute infections were also observed. Anti-B19V IgG was detected in 65.9% of patients with sickle cell disease and in 60% of donors, whereas the patients with thalassemia exhibited relatively low seroreactivity. The seroprevalence varied among the different age groups. In patients, it progressively increased with age, whereas in donors it reached a plateau. Based on partial NS1 fragments, all isolates detected were classified as subgenotype 1A with a tendency to elicit genetically complex infections. Interestingly, quasispecies occurred in the plasma of not only patients but also donors with even higher heterogeneity. The partial NS1 sequence examined did not exhibit positive selection. Quantitation of B19V with a conservative probe is a technically and practically useful approach. The extensive spread of B19V subgenotype 1A in patients and donors and its recent introduction into the countryside of the São Paulo State, Brazil were demonstrated; however, it is difficult to establish a relationship between viral sequences and the clinical outcomes of the infection.
Microparticles (MPs) are present in healthy subjects and their concentration increases in patients at high risk of thrombosis. We evaluated 10 patients with sickle cell anemia (SCA) treated with hydroxyurea (HU) and 13 SCA patients without this treatment. MP concentrations were determined by flow cytometry. Coagulation was evaluated using the thrombin-antithrombin complex (TAT) and D-dimers. Total MP concentrations were increased in the HU-treated group (265 × 106/ml vs. 67.45 × 106/ml; p = 0.0026), as well as MPs derived from RBC (67.83 × 106/ml vs. 26.31 × 106/ml; p = 0.05), monocytes (51.31 × 106/ml vs. 9.03 × 106/ml; p = 0.0084), monocytes with tissue factor (TF) expression (2.27 × 106/ml vs. 0.27 × 106/ml; p = 0.0058), endothelium (49.42 × 106/ml vs. 7.23 × 106/ml; p = 0.007) and endothelium with TF (1.42 × 106/ml vs. 0.26 × 106/ml; p = 0.0043). Furthermore, the concentrations of TAT (7.56 vs. 10.98 µg/l; p = 0.014) and D-dimers (0.65 vs. 1.29 µg/ml; p = 0.007) were reduced with HU. The MP elevation may suggest a direct cytotoxic effect of HU. Another explanation is a cell surface increase secondary to a megaloblastic process, resulting in increased vesicle release. In our opinion, the known benefits of HU on SCA patients, along with the reduction in coagulation activation, surpass its potential detrimental effect on MPs. Future studies should elucidate the role of MPs and demonstrate their significance in different contexts. © 2014 S. Karger AG, Basel
Since 2001, the Brazilian Ministry of Health has been coordinating a National Neonatal Screening Program (NNSP) that now covers all the 26 states and the Federal District of the Brazilian Republic and targets six diseases including sickle cell disease (SCD) and other hemoglobinopathies. In 2005, the program coverage reached 80% of the total live births. Since then, it has oscillated between 80% and 84% globally with disparities from one state to another (>95% in São Paulo State). The Ministry of Health has also published several Guidelines for clinical follow-up and treatment for the diseases comprised by the neonatal screening program. The main challenge was, and still is, to organize the public health network (SUS), from diagnosis and basic care to reference centers in order to provide comprehensive care for patients diagnosed by neonatal screening, especially for SCD patients. Considerable gains have already been achieved, including the implementation of a network within SUS and the addition of scientific and technological progress to treatment protocols. The goals for the care of SCD patients are the intensification of information provided to health care professionals and patients, measures to prevent complications, and care and health promotion, considering these patients in a global and integrated way, to reduce mortality and enhance their quality of life.
Human parvovirus B19 (B19V) infection can be a life-threatening condition among patients with hereditary (chronic) hemolytic anemias. Our objective was to characterize the infection molecularly among patients with sickle cell disease and thalassemia. Forty-seven patients (37 with sickle cell disease, and 10 with β-thalassemia major) as well as 47 healthy blood donors were examined for B19V infection by anti-B19V IgG enzyme immunoassay, quantitative PCR, which detects all B19V genotypes, and DNA sequencing. B19V viremia was documented in nine patients (19.1%) as two displayed acute infection and the rest had a low titre viremia (mean 3.4 × 10(4) copies/mL). All donors were negative for B19V DNA. Anti-B19V IgG was detected in 55.3% of the patients and 57.4% among the donors. Based on partial NS1 fragments, all patient isolates were classified as genotype 1 and subgenotype 1A. The evolutionary events of the examined partial NS1 gene sequence were associated with a lack of positive selection. The quantification of all B19V genotypes by a single hydrolytic probe is a technically useful method, but it is difficult to establish relationships between B19V sequence characteristics and infection outcome.
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