RESUMO
The number of individuals with the sickle cell trait exceeds 300 million worldwide, making sickle cell disease one of the most common monogenetic diseases globally. Because of the high frequency of sickle cell disease, reproductive counseling is of crucial importance. In addition, unlike other carrier states, Sickle Cell Trait (SCT) seems to be a risk factor for several clinical complications, such as extreme exertional injury, chronic kidney disease, and complications during pregnancy and surgery. This expert panel believes that increasing knowledge about these clinical manifestations and their prevention and management can be a useful tool for all healthcare providers involved in this issue.
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We report data on survival and complications for a longitudinal cohort of 709 transfusion-dependent ß-thalassemia major patients (51.1% males) born between 1970 and 1997 and followed through 2020 at seven major centers in Italy. Overall survival probability at 30 years was 83.6% (95%CI: 78.5-89.1) in the oldest birth cohort (1970-1974) compared with 93.3% (95%CI: 88.6-98.3) in the youngest birth cohort (1985-1997) (p = 0.073). Females showed better survival than males (p = 0.022). There were a total of 93 deaths at a median age of 23.2 years with the most frequent disease-related causes being heart disease (n = 53), bone marrow transplant (BMT) complication (n = 10), infection (n = 8), liver disease (n = 4), cancer (n = 3), thromboembolism (n = 2) and severe anemia (n = 1). There was a steady decline in the number of deaths due to heart disease from the year 2000 onwards and no death from BMT was observed after the year 2010. A progressive decrease in the median age of BMT was observed in younger birth cohorts (p < 0.001). A total of 480 (67.7%) patients developed ≥1 complication. Patients in younger birth cohorts demonstrated better complication-free survival (p < 0.001) which was comparable between sexes (p = 0.230). Independent risk factors for death in multivariate analysis included heart disease (HR: 4.63, 95%CI: 1.78-12.1, p = 0.002), serum ferritin >1000 ng/mL (HR: 15.5, 95%CI: 3.52-68.2, p < 0.001), male sex (HR: 2.75, 95%CI: 0.89-8.45, p = 0.078), and splenectomy (HR: 6.97, 95%CI: 0.90-54.0, p < 0.063). Survival in patients with ß-thalassemia major continues to improve with adequate access to care, best practice sharing, continued research, and collaboration between centers.
Assuntos
Cardiopatias , Tromboembolia , Talassemia beta , Feminino , Humanos , Masculino , Adulto Jovem , Adulto , Talassemia beta/complicações , Talassemia beta/terapia , Transplante de Medula Óssea , Fatores de Risco , Tromboembolia/complicaçõesRESUMO
BACKGROUND: The correlation between thalassemia and malignancies other than hepatocellular carcinoma (HCC) and the possible relationship between other hemoglobinopathies and tumor risk have been poorly evaluated. METHODS: Eight Italian specialized centers evaluated the incidence of malignant neoplasms in hemoglobinopathies as well as their sites and features. The study cohort included 4631 patients followed between 1970 and 2021 (transfusion-dependent ß-thalassemia, 55.6%; non-transfusion-dependent thalassemia, 17.7%; sickle cell disease, 17.6%; hemoglobin H disease, 8.3%). RESULTS: A total of 197 diagnoses of cancer were reported (incidence rate, 442 cases per 100,000 person-years). The liver was the most frequent site of tumors in both sexes, with a higher incidence (190 cases per 100,000 person-years) in comparison with the general population found in all types of hemoglobinopathies (except hemoglobin H disease). In recent years, tumors have become the second cause of death in patients with transfusion-dependent thalassemia. A lower risk of breast and prostate cancer was observed in the whole group of patients with hemoglobinopathies. The first cancer diagnoses dated back to the 1980s, and the incidence rate sharply increased after the 2000s. However, although the incidence rate of cancers of all sites but the liver continued to show an increasing trend, the incidence of HCC showed stability. CONCLUSIONS: These findings provide novel insights into the relationship between cancer and hemoglobinopathies and suggest that the overall risk is not increased in these patients. HCC has been confirmed as the most frequent tumor, but advances in chelation and the drugs that have led to the eradication of hepatitis C may explain the recent steadiness in the number of diagnoses that is reported here.
Assuntos
Carcinoma Hepatocelular , Hemoglobinopatias , Neoplasias Hepáticas , Talassemia alfa , Masculino , Feminino , Humanos , Incidência , Talassemia alfa/diagnóstico , Talassemia alfa/epidemiologia , Carcinoma Hepatocelular/epidemiologia , Neoplasias Hepáticas/epidemiologia , Hemoglobinopatias/epidemiologia , Hemoglobinopatias/diagnósticoRESUMO
Mutations in the ferroportin (FPN) gene SLC40A1 alter iron recycling and cause disturbances in iron homeostasis. The variants of TMPRSS6 contribute to the development of iron deficiencies. In this study, we determined the role of FPN and TMPRSS6 gene polymorphisms in the modulation of iron homeostasis based on biochemical parameters. PCR analysis and sequencing were performed to determine the single nucleotide polymorphisms (SNPs) SLC40A1 c.44−24G>C (rs1439816), SLC40A1 c.663T>C (rs2304704), and TMPRSS6 c.2207T>C (rs855791). Hemoglobin concentration and iron status were determined by standard procedures. We studied 79 iron-loaded individuals for SLC40A1 polymorphisms. Interestingly, 35/79 individuals with SLC40A1 SNPs also carried a TMPRSS6 c.2207T>C polymorphism. The biochemical values of the iron overloaded individuals were compared to those of the individuals carrying TMPRSS6 SNPs and the healthy individuals (wild-type group). The ferritin concentration, transferrin saturation % (TS%), and hemoglobin concentration were significantly higher in the participants with FPN SNPs than in the other three groups. The ferritin concentration and TS% were higher in participants with both SLC40A1 and TMPRSS6 SNPs than in the TMPRSS6 and wild-type groups, while hemoglobin concentration was significantly higher than that in the TMPRSS6 SNP group only. The participants with TMPRSS6 SNPs had significantly lower ferritin concentration, TS%, and hemoglobin concentration than all the other groups. SLC40A1 and TMPRSS6 SNPs might act in the opposite direction, preventing the development of severe iron overload, and the modulation of the iron status by TMPRSS6 SNPs might provide protection.
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Coronavirus Disease (COVID-19) can be considered as a human pathological model of inflammation combined with hypoxia. In this setting, both erythropoiesis and iron metabolism appear to be profoundly affected by inflammatory and hypoxic stimuli, which act in the opposite direction on hepcidin regulation. The impact of low blood oxygen levels on erythropoiesis and iron metabolism in the context of human hypoxic disease (e.g., pneumonia) has not been fully elucidated. This multicentric observational study was aimed at investigating the prevalence of anemia, the alterations of iron homeostasis, and the relationship between inflammation, hypoxia, and erythropoietic parameters in a cohort of 481 COVID-19 patients admitted both to medical wards and intensive care units (ICU). Data were collected on admission and after 7 days of hospitalization. On admission, nearly half of the patients were anemic, displaying mild-to-moderate anemia. We found that hepcidin levels were increased during the whole period of observation. The patients with a higher burden of disease (i.e., those who needed intensive care treatment or had a more severe degree of hypoxia) showed lower hepcidin levels, despite having a more marked inflammatory pattern. Erythropoietin (EPO) levels were also lower in the ICU group on admission. After 7 days, EPO levels rose in the ICU group while they remained stable in the non-ICU group, reflecting that the initial hypoxic stimulus was stronger in the first group. These findings strengthen the hypothesis that, at least in the early phases, hypoxia-driven stimuli prevail over inflammation in the regulation of hepcidin and, finally, of erythropoiesis.
Assuntos
Anemia , COVID-19 , Eritropoetina , Eritropoese/fisiologia , Hepcidinas , Humanos , Hipóxia , Inflamação , FerroRESUMO
BACKGROUND AND AIM: Dysregulation of iron metabolism and hyper-inflammation are two key points in the pathogenesis of coronavirus disease 2019 (COVID-19). Since high hepcidin levels and low serum iron can predict COVID-19 severity and mortality, we decided to investigate iron metabolism and inflammatory response in 32 COVID-19 adult patients with a diagnosis of COVID-19 defined by a positive result of RT-PCR nasopharyngeal swab, and admitted to an Italian emergency department for acute respiratory failure at different degree. METHODS: Patients were stratified in 3 groups based on PaO2/FiO2 ratio at admission: 13 (41%) were normoxemic at rest and suffered from exertional dyspnea (group 1); 14 (44%) had a mild respiratory failure (group 2), and 5 (15%) a severe hypoxiemia (group 3). RESULTS: White blood cells were significantly higher in group 3, while lymphocytes and hemoglobin were significantly reduced. Serum iron, transferrin saturation, non-transferrin-bound iron (NTBI) and ferritin were significantly increased in group 2. All the groups showed high hepcidin levels, but in group 3 this parameter was significantly altered. It is noteworthy that in group 1 inflammatory and oxidative indices were both within the normal range. CONCLUSIONS: We are aware that our study has some limitations, the small number of enrolled patients and the short period of data collection, but few works have been performed in the Emergency Room. However, we strongly believe that our results confirm the pivotal role of both iron metabolism dysregulation and hyper-inflammatory response in the pathogenesis of tissue and organ damage in COVID-19 patients.
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COVID-19 , Adulto , Serviço Hospitalar de Emergência , Hepcidinas/metabolismo , Homeostase , Humanos , Ferro/metabolismo , Estudos Prospectivos , SARS-CoV-2RESUMO
Congenital anemias may be complicated by immune-mediated hemolytic crisis. Alloantibodies are usually seen in chronically transfused patients, and autoantibodies have also been described, although they are rarely associated with overt autoimmune hemolytic anemia (AIHA), a serious and potentially life-threatening complication. Given the lack of data on the AIHA diagnosis and management in congenital anemias, we retrospectively evaluated all clinically relevant AIHA cases occurring at a referral center for AIHA, hemoglobinopathies, and chronic hemolytic anemias, focusing on clinical management and outcome. In our cohort, AIHA had a prevalence of 1% (14/1410 patients). The majority were warm AIHA. Possible triggers were recent transfusion, infection, pregnancy, and surgery. All the patients received steroid therapy as the first line, and about 25% required further treatment, including rituximab, azathioprine, intravenous immunoglobulins, and cyclophosphamide. Transfusion support was required in 57% of the patients with non-transfusion-dependent anemia, and recombinant human erythropoietin was safely administered in one third of the patients. AIHA in congenital anemias may be challenging both from a diagnostic and a therapeutic point of view. A proper evaluation of hemolytic markers, bone marrow compensation, and assessment of the direct antiglobulin test is mandatory.
RESUMO
This expert opinion originally developed by a panel of the Italian Society of Thalassemias and Hemoglobinopathies (SITE), reviewed and adopted by the European Hematology Association (EHA) through the EHA Scientific Working Group on Red Cells and Iron, has been developed as priority decision-making algorithm on evidence and consensus with the aim to identify which patients with transfusion-dependent beta-thalassemia (TDT) could benefit from a gene therapy (GT) approach. Even if the wide utilized and high successful allogeneic hematopoietic stem-cell transplantation provides the possibility to cure several patients a new scenario has been opened by GT. Therefore, it is important to establish the patients setting for whom it is priority indicated, particularly in the early phase of the diffuse use outside experimental trials conducted in high selected centers. Moreover, actual price, limited availability, and resources disposal constitute a further indication to a rational and progressive approach to this innovative treatment. To elaborate this algorithm, the experience with allogeneic transplantation has been used has a predictive model. In this large worldwide experience, it has been clearly demonstrated that key for the optimal transplant outcome is optimal transfusion and chelation therapy in the years before the procedure and consequently optimal patient's clinical condition. In the document, different clinical scenarios have been considered and analyzed for the possible impact on treatment outcome. According to the European Medicine Agency (EMA) for the GT product, this expert opinion must be considered as a dynamic, updatable, priority-based indications for physicians taking care of TDT patients.
Assuntos
Anemia Falciforme/diagnóstico , Anemia Falciforme/epidemiologia , Refugiados , Adolescente , Criança , Pré-Escolar , Serviço Hospitalar de Emergência , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Lactente , Itália/epidemiologia , Masculino , Programas de Rastreamento/métodos , Projetos Piloto , Adulto JovemRESUMO
The purpose of this case study is to describe the physiological characteristics of a patient with the low-oxygen affinity Titusville hemoglobin variant. A 46-yr-old man with exertional dyspnea was diagnosed with a mediastinal lymphadenopathy of unknown origin and, to obtain definitive diagnosis by biopsy, underwent endobronchial ultrasound-guided transbronchial needle aspirate under sedation and video-assisted thoracoscopy under general anesthesia. High inspired fraction of oxygen ( FIO2 ) was used to guarantee adequate oxygenation even during the one-lung ventilation needed for thoracoscopy. Following radial and pulmonary arterial catheterization, continuous mixed-venous oxygen saturation ( SVO2 ), cardiac output, oxygen delivery (DO2), oxygen consumption (VÌo2), and oxygen extraction ratio (ERO2) were measured. Serial blood gas analyses were obtained at different FIO2 . Anesthesia and surgery were carried out safely. Data obtained during the clinical case were utilized to 1) construct an in vivo Titusville hemoglobin dissociation curve and 2) describe oxygen delivery and consumption of a human with Titusville mutation. Titusville hemoglobin showed relatively high P50 (i.e., 30 vs. normal of 27) and very low cooperativity (Hill coefficient of 1.45 vs. normal 2.27), which was compensated in our patient by increases in cardiac output, rather than by augmenting oxygen extraction.
Assuntos
Hemoglobinas Anormais/metabolismo , Consumo de Oxigênio/fisiologia , Oxigênio/metabolismo , Anestesia Geral/métodos , Débito Cardíaco/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Troca Gasosa Pulmonar/fisiologia , Cirurgia Torácica/métodosRESUMO
ß-thalassemia is caused by ß-globin gene mutations resulting in reduced (ß+) or absent (ß0) hemoglobin production. Patient life expectancy has recently increased, but the need for chronic transfusions in transfusion-dependent thalassemia (TDT) and iron chelation impairs quality of life1. Allogeneic hematopoietic stem cell (HSC) transplantation represents the curative treatment, with thalassemia-free survival exceeding 80%. However, it is available to a minority of patients and is associated with morbidity, rejection and graft-versus-host disease2. Gene therapy with autologous HSCs modified to express ß-globin represents a potential therapeutic option. We treated three adults and six children with ß0 or severe ß+ mutations in a phase 1/2 trial ( NCT02453477 ) with an intrabone administration of HSCs transduced with the lentiviral vector GLOBE. Rapid hematopoietic recovery with polyclonal multilineage engraftment of vector-marked cells was achieved, with a median of 37.5% (range 12.6-76.4%) in hematopoietic progenitors and a vector copy number per cell (VCN) of 0.58 (range 0.10-1.97) in erythroid precursors at 1 year, in absence of clonal dominance. Transfusion requirement was reduced in the adults. Three out of four evaluable pediatric participants discontinued transfusions after gene therapy and were transfusion independent at the last follow-up. Younger age and persistence of higher VCN in the repopulating hematopoietic cells are associated with better outcome.
Assuntos
Transfusão de Sangue , Osso e Ossos/patologia , Terapia Genética , Transplante de Células-Tronco Hematopoéticas , Células-Tronco Hematopoéticas/citologia , Talassemia beta/genética , Talassemia beta/terapia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Resultado do TratamentoRESUMO
Although its prevalence is unknown, liver involvement by sickle cell disease is not uncommon and encompasses different clinical spectra including non cholestatic and cholestatic disorders. Few data have been provided on chronic sickle cell intrahepatic cholestasis (SCIC) clinical course, although cirrhosis has been reported in sickle cell disease. However, no effective therapeutic approaches have been recognized either to prevent or treat this condition. Here we present two cases of adult sickle cell disease patients with decompensated cirrhosis. Their liver biopsies showed sickle cell thrombi within the hepatic sinusoids. Despite erythroexchange (EEX) transfusions, both patients suffered from major sickle cell disease-related events, suggesting that EEX transfusions may not be enough to impact on advanced liver involvement by sickle cell disease.
Assuntos
Anemia Falciforme , Transfusão de Eritrócitos , Cirrose Hepática , Adulto , Anemia Falciforme/complicações , Anemia Falciforme/patologia , Anemia Falciforme/terapia , Feminino , Humanos , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Cirrose Hepática/terapia , Masculino , Pessoa de Meia-IdadeRESUMO
The PPOX gene encodes for the protoporphyrinogen oxidase, which is involved in heme production. The partial deficiency of protoporphyrinogen oxidase causes variegate porphyria. The tissue-specific regulation of other heme biosynthetic enzymes is extensively studied, but the information concerning transcriptional and post-transcriptional regulation of PPOX gene expression is scarcely available. In this study, we characterized functions of three variants identified in the regulatory regions of the PPOX gene, which show a novel role for the 5' untranslated exon 1. Using luciferase assays and RNA analysis, we demonstrated that only c.1-883G>C promoter variant causes a significant loss in the transcriptional activity of PPOX gene whereas c.1-413G>T 5' UTR variant inhibits translation of PPOX mRNA and c.1-176G>A splicing variant causes 4bp deletion in 5' UTR of PPOX mRNA variant 2. These observations indicate that the regulation of PPOX gene expression can also occur through a post-transcriptional modulation of the amount of gene product and that this modulation can be mediated by 5' untranslated exon 1. Moreover this study confirms that these regulatory regions represent an important molecular target for the pathogenesis of variegate porphyria.
Assuntos
Epigênese Genética , Flavoproteínas/genética , Proteínas Mitocondriais/genética , Mutação , Porfiria Variegada/genética , Protoporfirinogênio Oxidase/genética , Sequências Reguladoras de Ácido Nucleico/genética , Regiões 5' não Traduzidas/genética , Coleta de Amostras Sanguíneas , Linhagem Celular Tumoral , Éxons , Regulação da Expressão Gênica , Humanos , Porfiria Variegada/etiologiaRESUMO
Iron refractory iron deficiency anemia (IRIDA) is a rare hereditary disease caused by mutations in TMPRSS6 gene encoding Matriptase-2, a negative regulator of hepcidin transcription. Up to now, 53 IRIDA patients from 35 families with different ethnic origins have been reported and 41 TMPRSS6 mutations have been identified. TMPRSS6 polymorphisms are more frequent than mutations, and have been associated with variation in iron and hematologic parameters. Our study evaluated their presence in 113 subjects with iron deficiency anemia (IDA) partially responsive to oral iron therapy and in 50 healthy blood donors. Thalassemic trait was diagnosed in 38 patients. Sequencing analysis of TMPRSS6 gene revealed that the frequency of several polymorphisms was markedly different between IDA subjects and controls. In particular, the V736A TMPRSS6 polymorphism was associated to moderately lower hemoglobin, mean corpuscular volume, and mean corpuscular hemoglobin levels, and in thalassemia carriers with marked anemia and microcytosis. A new variant-H448R- and two uncommon polymorphisms -A719T and V795I- were also identified. These results indicate that TMPRSS6 polymorphisms are more frequent in subjects with persistent IDA than in healthy controls, and in thalassemia carriers V736A variant may account for lower hemoglobin and MCV levels. Further studies in larger court of patients are necessary to identify potential haplotypes and polymorphisms responsible for low response to oral iron treatment and may be useful for planning a correct iron supplementation.
Assuntos
Anemia Ferropriva/tratamento farmacológico , Compostos Ferrosos/uso terapêutico , Hematínicos/uso terapêutico , Proteínas de Membrana/genética , Polimorfismo de Nucleotídeo Único , Serina Endopeptidases/genética , Administração Oral , Adolescente , Adulto , Idoso , Anemia Ferropriva/genética , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Compostos Ferrosos/administração & dosagem , Hematínicos/administração & dosagem , Hemoglobinas/análise , Heterozigoto , Homozigoto , Humanos , Ferro/sangue , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto JovemRESUMO
Patients with thalassemia are often exposed to several risk factors for developing hepatocellular carcinoma (HCC) due to their repeated transfusions. However, even transfusion-independent patients with thalassemia intermedia (TI) can develop HCC, which is mainly attributed to a state of iron overload. We report here two cases and review the literature for the association between TI and HCC. Along with our cases, a total of 36 cases of HCC in thalassemic patients were reported in the literature. Of these, 22 (61%) were TI patients with 6 (27%) of them being hepatitis B and C negative. There was no consistency in their characteristics; therefore, we recommended screening thresholds for HCC in TI patients based on their total liver iron concentration (LIC).
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Carcinoma Hepatocelular/etiologia , Sobrecarga de Ferro/complicações , Neoplasias Hepáticas/etiologia , Talassemia beta/complicações , Hematopoese Extramedular , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Reação TransfusionalRESUMO
Heart failure due to myocardial iron overload remains the leading cause of morbidity and mortality in adult thalassemia major (TM) patients. We evaluated the removal of cardiac iron and the changes of cardiac function by different iron chelation in TM patients by T2* cardiac magnetic resonance (CMR). Sixty-seven TM patients (27 males/40 females; mean age, 35 ± 6 years) on different chelation regimens underwent T2* CMR at baseline (t (0)), after 6-14 months (t (1)) and after 32 ± 7 months (t (2)). Patients were divided in four groups according to chelation treatment: group A (deferasirox), group B (deferoxamine), group C (combined treatment, deferoxamine plus deferiprone) and group D (deferiprone alone). Myocardial T2* at t (0) was <10 ms in 8 patients, between 10 and 20 ms in 22 patients and ≥ 20 ms in 37 patients. Progressive changes in T2* were observed at t (1) and t (2). Ten patients (10/36, 27.8 %) in group A, three patients (3/15, 20 %) in group B and three patients (3/12, 25 %) in group C moved from an abnormal T2* to normal values. We observed an improvement of left ventricular ejection fraction and a reduction of end-systolic and end-diastolic left ventricular volumes only in patients in group A with baseline cardiac T2* between 10 and 20 ms. Rigorous compliance to any chelation therapy at proper doses significantly improve myocardial T2*. Treatment with deferasirox significantly improves left ventricular function. Combination therapy seems to ameliorate cardiac T2* in a shorter period of time in severe siderosis.
Assuntos
Benzoatos/uso terapêutico , Desferroxamina/uso terapêutico , Insuficiência Cardíaca/prevenção & controle , Coração/fisiopatologia , Quelantes de Ferro/uso terapêutico , Miocárdio/química , Piridonas/uso terapêutico , Triazóis/uso terapêutico , Talassemia beta/complicações , Adulto , Comorbidade , Deferasirox , Deferiprona , Desferroxamina/administração & dosagem , Quimioterapia Combinada , Feminino , Seguimentos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/etiologia , Humanos , Masculino , Miocárdio/patologia , Cooperação do Paciente , Estudos Prospectivos , Piridonas/administração & dosagem , Volume Sistólico , Adulto Jovem , Talassemia beta/metabolismo , Talassemia beta/patologiaRESUMO
BACKGROUND: Patients with ß thalassemia intermedia can have substantial iron overload, irrespectively of their transfusion status, secondary to increased intestinal iron absorption. This study evaluates whether iron overload in patients with ß thalassemia intermedia is associated with morbidity. DESIGN AND METHODS: This was a cross-sectional study of 168 patients with ß thalassemia intermedia treated at two centers in Lebanon and Italy. Data on demographics, splenectomy status, transfusion status, and presence of co-morbidities were retrieved. Laboratory values of serum ferritin, fetal and total hemoglobin levels, as well as platelet and nucleated red blood cell counts were also obtained. Iron burden was determined directly by measuring liver iron concentration using magnetic resonance imaging. Patients were subdivided according to transfusion and splenectomy status into groups with phenotypes of different severity. RESULTS: The mean age of the patients was 35.2 ± 12.6 years and 42.9% of them were male. The mean liver iron concentration was 8.4 ± 6.7 mg Fe/g dry weight. On multivariate logistic regression analysis, after adjusting for age, gender, splenectomy status, transfusion status, and laboratory indices, an increase in 1 mg Fe/g dry weight liver iron concentration was independently and significantly associated with higher odds of thrombosis, pulmonary hypertension, hypothyroidism, osteoporosis, and hypogonadism. A liver iron concentration of at least 7 and at least 6 mg Fe/g dry weight were the best thresholds for discriminating the presence and absence of vascular and endocrine/bone morbidities, respectively (area under the receiver-operating characteristic curve: 0.72, P<0.001). Elevated liver iron concentration was associated with an increased rate of morbidity in patients with phenotypes of all severity, with a steeper increase in the rate of vascular morbidity being attributed to aging, and an earlier appearance of endocrine and bone disease. CONCLUSIONS: Elevated liver iron concentration in patients with ß thalassemia intermedia is a marker of increased vascular, endocrine, and bone disease.
Assuntos
Ferro/metabolismo , Fígado/metabolismo , Talassemia beta/metabolismo , Talassemia beta/mortalidade , Adulto , Biomarcadores/metabolismo , Plaquetas/metabolismo , Plaquetas/patologia , Transfusão de Sangue , Estudos Transversais , Contagem de Eritrócitos , Eritrócitos Anormais/metabolismo , Eritrócitos Anormais/patologia , Feminino , Ferritinas/sangue , Hemoglobina Fetal/metabolismo , Humanos , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/mortalidade , Sobrecarga de Ferro/patologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Esplenectomia , Talassemia beta/patologiaRESUMO
Transmembrane Protease, Serine 6 (TMPRSS6) has an important role in iron homeostasis and its mutations, performed in TMPRSS6-deficient mice, have been recently associated with iron-refractory iron deficiency anaemia (IRIDA). Several variants of TMPRSS6 have been already identified; however the role of polymorphisms and TMPRSS6 haplotypes, causing iron deficiency anaemia, have not yet been investigated. This study sequenced the TMPRSS6 gene in 16 subjects with IRIDA phenotype and identified 27 DNA polymorphisms. Eight single nucleotide polymorphisms and four haplotypes were significantly associated with iron-refractory anaemia (P < 0·001). Our preliminary results suggest a possible association between specific haplotypes of TMPRSS6 and IRIDA.