Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 115
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Cochrane Database Syst Rev ; 11: CD011626, 2023 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-37975597

RESUMO

BACKGROUND: Beta-thalassaemia is an inherited blood disorder that reduces the production of haemoglobin. The most severe form requires recurrent blood transfusions, which can lead to iron overload. Cardiovascular dysfunction caused by iron overload is the leading cause of morbidity and mortality in people with transfusion-dependent beta-thalassaemia. Iron chelation therapy has reduced the severity of systemic iron overload, but removal of iron from the myocardium requires a very proactive preventive strategy. There is evidence that calcium channel blockers may reduce myocardial iron deposition. This is an update of a Cochrane Review first published in 2018. OBJECTIVES: To assess the effects of calcium channel blockers plus standard iron chelation therapy, compared with standard iron chelation therapy (alone or with a placebo), on cardiomyopathy due to iron overload in people with transfusion-dependent beta thalassaemia. SEARCH METHODS: We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books, to 13 January 2022. We also searched ongoing trials databases and the reference lists of relevant articles and reviews. SELECTION CRITERIA: We included randomised controlled trials (RCTs) of calcium channel blockers combined with standard chelation therapy versus standard chelation therapy alone or combined with placebo in people with transfusion-dependent beta thalassaemia. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. We used GRADE to assess certainty of evidence. MAIN RESULTS: We included six RCTs (five parallel-group trials and one cross-over trial) with 253 participants; there were 126 participants in the amlodipine arms and 127 in the control arms. The certainty of the evidence was low for most outcomes at 12 months; the evidence for liver iron concentration was of moderate certainty, and the evidence for adverse events was of very low certainty. Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may have little or no effect on cardiac T2* values at 12 months (mean difference (MD) 1.30 ms, 95% confidence interval (CI) -0.53 to 3.14; 4 trials, 191 participants; low-certainty evidence) and left ventricular ejection fraction (LVEF) at 12 months (MD 0.81%, 95% CI -0.92% to 2.54%; 3 trials, 136 participants; low-certainty evidence). Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may reduce myocardial iron concentration (MIC) after 12 months (MD -0.27 mg/g, 95% CI -0.46 to -0.08; 3 trials, 138 participants; low-certainty evidence). The results of our analysis suggest that amlodipine has little or no effect on heart T2*, MIC, or LVEF after six months, but the evidence is very uncertain. Amlodipine plus standard iron chelation compared with standard iron chelation (alone or with placebo) may increase liver T2* values after 12 months (MD 1.48 ms, 95% CI 0.27 to 2.69; 3 trials, 127 participants; low-certainty evidence), but may have little or no effect on serum ferritin at 12 months (MD 0.07 µg/mL, 95% CI -0.20 to 0.35; 4 trials, 187 participants; low-certainty evidence), and probably has little or no effect on liver iron concentration (LIC) after 12 months (MD -0.86 mg/g, 95% CI -4.39 to 2.66; 2 trials, 123 participants; moderate-certainty evidence). The results of our analysis suggest that amlodipine has little or no effect on serum ferritin, liver T2* values, or LIC after six months, but the evidence is very uncertain. The included trials did not report any serious adverse events at six or 12 months of intervention. The studies did report mild adverse effects such as oedema, dizziness, mild cutaneous allergy, joint swelling, and mild gastrointestinal symptoms. Amlodipine may be associated with a higher risk of oedema (risk ratio (RR) 5.54, 95% CI 1.24 to 24.76; 4 trials, 167 participants; very low-certainty evidence). We found no difference between the groups in the occurrence of other adverse events, but the evidence was very uncertain. No trials reported mortality, cardiac function assessments other than echocardiographic estimation of LVEF, electrocardiographic abnormalities, quality of life, compliance with treatment, or cost of interventions. AUTHORS' CONCLUSIONS: The available evidence suggests that calcium channel blockers may reduce MIC and may increase liver T2* values in people with transfusion-dependent beta thalassaemia. Longer-term multicentre RCTs are needed to assess the efficacy and safety of calcium channel blockers for myocardial iron overload, especially in younger children. Future trials should also investigate the role of baseline MIC in the response to calcium channel blockers, and include a cost-effectiveness analysis.


Assuntos
Cardiomiopatias , Sobrecarga de Ferro , Talassemia beta , Criança , Humanos , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Bloqueadores dos Canais de Cálcio/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/prevenção & controle , Sobrecarga de Ferro/complicações , Ferro/uso terapêutico , Cardiomiopatias/etiologia , Cardiomiopatias/prevenção & controle , Anlodipino/efeitos adversos , Quelantes de Ferro/efeitos adversos , Ferritinas , Edema
2.
Drug Chem Toxicol ; 45(6): 2814-2824, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34663156

RESUMO

Morus nigra L. is a plant popularly known as 'amoreira preta', very used in folk medicine. Iron overload (hemochromatosis) is a clinical condition that causes damage to various tissues due to oxidative stress. Therapy to control iron overload is still unsatisfactory. The protective effect on oxidative stress induced by iron overload was verified. Phytochemical characterization was evaluated by UHPLC-MS/MS. The in silico toxicity predictions of the main phytochemicals were performed via computer simulation. To induce iron overload, the animals received iron dextran (50 mg/kg/day). The test groups received doses of 500 and 1000 mg/kg of M. nigra extract for six weeks. Body weight, organosomatic index, serum iron, hepatic markers, cytokines, interfering factors in iron metabolism, enzymatic and histopathological evaluations were analyzed. Vanillic acid, caffeic acid, 6-hydroxycoumarin, p-coumaric acid, ferulic acid, rutin, quercitrin, resveratrol, apigenin and kaempferol were identified in the extract. In addition, in silico toxic predictions showed that the main compounds presented a low probability of toxic risk. The extract of M. nigra showed to control the mediators of inflammation and to reduce iron overload in several tissues. Our findings illustrate a novel therapeutic action of M. nigra leaves on hemochromatosis caused by iron overload.


Assuntos
Hemocromatose , Sobrecarga de Ferro , Morus , Animais , Morus/química , Morus/metabolismo , Quempferóis/análise , Quempferóis/farmacologia , Resveratrol/farmacologia , Hemocromatose/tratamento farmacológico , Apigenina/análise , Apigenina/farmacologia , Ácido Vanílico/farmacologia , Espectrometria de Massas em Tandem , Simulação por Computador , Dextranos/análise , Dextranos/metabolismo , Dextranos/farmacologia , Extratos Vegetais/uso terapêutico , Folhas de Planta/química , Estresse Oxidativo , Sobrecarga de Ferro/prevenção & controle , Compostos Fitoquímicos/análise , Rutina/farmacologia , Ferro/toxicidade , Ferro/análise , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo
3.
Food Funct ; 12(16): 7321-7328, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34173816

RESUMO

This study proposed to investigate the effect of Ilex paraguariensis infusion on the absorption of non-heme iron in hereditary hemochromatosis (HH) patients with the HFE genotype. A two-way randomized, controlled, crossover trial was conducted on patients, aged 29-69 years, undergoing maintenance therapy. Fourteen HFE-HH patients ingested a meal containing 11.4 mg iron and 200 mL either of water (control) or of Ilex paraguariensis leaf infusion. The beverages were offered in random order, at intervals separated by a washout period of 7 days. Active surveillance showed no adverse effects. Blood samples were drawn shortly before and 1, 2, 3, and 4 h after the meal for serum iron measurement. A significant reduction in the postprandial serum iron was observed for HH patients after intake of the Ilex paraguariensis infusion (area under the curve (AUC) expressed as mean ± SEM: 173.3 ± 44.7 µmol h-1 L-1) compared to water (1449.4 ± 241.5 µmol h-1 L-1) (p < 0.001). In summary, intake of Ilex paraguariensis leaf infusion significantly inhibited the absorption of iron in patients with HH and, therefore, should be considered as a potential adjuvant for iron overload control.


Assuntos
Hemocromatose/sangue , Ilex paraguariensis/metabolismo , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/prevenção & controle , Extratos Vegetais/farmacologia , Folhas de Planta/metabolismo , Adulto , Idoso , Bebidas , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/sangue
5.
Arch Dis Child ; 105(11): 1041-1048, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32994214

RESUMO

OBJECTIVES: Cardiac T2* MRI (T2*CMR), for accurate estimation of myocardial siderosis, was introduced as part of a QI collaborative to optimise chelation therapy in order to improve cardiac morbidity in transfusion dependent thalassaemia (TDT) patients. We report the impact of this QI initiative from two thalassaemia centres from this collaborative. DESIGN AND SETTING: A key driver based quality initiative was implemented to improve chelation in TDT patients registered at these two centres in Karachi, Pakistan. Protocol optimisation and compliance to treatment through training, communication and feedback were used as the drivers for QI intervention. Preintervention variables (demographics, chelation history, T2*CMR, echocardiography and holters) were collected from January 2015 to December 2016) and compared with variables in the post implementation phase (January to December 2019). A standardised adverse event severity for chelators and its management was devised for safe drug therapy as well as ensuring compliance to the regimen. Preintervention and postintervention variables were compared using non-parametric test. P value<0.05 was statistically significant. RESULTS: 100 patients with TDT, median age 17 (9-34) years, were included. An increase or stabilisation of T2*CMR was documented in 82% patients in the postintervention phase especially in patients with severe myocardial iron overload (5.5 vs 5.3 ms, p <0.01). Significantly fewer patients had abnormal echocardiographic findings (3.5% vs 26%, p <0.05) in the postintervention versus preintervention period. CONCLUSION: This QI initiative improved the chelation therapy leading to improved cardiac status in TDT patients at the participating centres.


Assuntos
Terapia por Quelação/métodos , Cardiopatias/prevenção & controle , Coração/diagnóstico por imagem , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/prevenção & controle , Talassemia/terapia , Adolescente , Adulto , Transfusão de Sangue , Criança , Protocolos Clínicos , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Paquistão , Melhoria de Qualidade , Adulto Jovem
6.
Indian J Pharmacol ; 52(3): 172-178, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32873999

RESUMO

BACKGROUND AND OBJECTIVES: Patients with beta-thalassemia require lifelong blood transfusions, leading to chronic iron overload, which can lead to growth retardation, as well as hinder sexual development during the adolescent period and dysfunction of organs such as heart, pancreas, and endocrine glands. These patients are in need of lifelong transfusion therapy and hence lifelong iron chelation therapy as well. Hence, this study was aimed to assess the effectiveness of deferasirox for iron chelation in pediatric thalassemia cases in a tertiary care hospital of Eastern India. SUBJECTS AND METHODS: This prospective, observational, hospital-based study was conducted from June 2015 to December 2016. Two hundred and fifty patients were assessed for eligibility, of which 174 were included. Effectiveness of deferasirox was observed by measuring serum ferritin levels which were monitored at the end of every 3 months till 1 year. We also evaluated the compliance with deferasirox therapy in the same study cohort. RESULTS: The serum ferritin level reduced significantly at the end of 12 months in comparison to baseline (P = 0.04). There was a mean absolute decrease in serum ferritin only in the dose range of 21-30 mg/kg/day. Approximately 90% of the patients had 100% compliance with deferasirox therapy. CONCLUSIONS: Deferasirox is an effective iron chelator when started at an optimum time and with optimum dose. At least 1 year of deferasirox therapy is needed for a significant lowering of serum ferritin levels of pediatric thalassemia patients on multiple blood transfusions.


Assuntos
Transfusão de Sangue , Deferasirox/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/prevenção & controle , Talassemia beta/terapia , Adolescente , Fatores Etários , Biomarcadores/sangue , Criança , Pré-Escolar , Deferasirox/efeitos adversos , Feminino , Ferritinas/sangue , Humanos , Índia , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/diagnóstico , Masculino , Estudos Prospectivos , Centros de Atenção Terciária , Fatores de Tempo , Resultado do Tratamento , Talassemia beta/sangue , Talassemia beta/diagnóstico
7.
Metallomics ; 12(10): 1494-1507, 2020 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-32852491

RESUMO

Iron plays an essential role in preventing iron deficiency anemia and ensuring the healthy growth of animals. The special physiological condition of piglets is the main cause of iron deficiency. Iron metabolism in the intestine is the basis for understanding the effects of iron on the health of piglets. In order to scientifically evaluate dietary iron supplementation doses, it is necessary to recognize the effects of iron deficiency and iron overload on piglet intestinal health. Besides, iron as a cofactor is essential for the growth of microorganisms, and microorganisms compete with the host to absorb iron. Under the stress of iron deficiency and iron overload, various control schemes (such as precise nutrition, element balance, elimination of oxidation, etc.) are effective measures to eliminate adverse effects. In this review, we comprehensively review recent findings on the effects of iron deficiency and iron overload on intestinal health. This review will provide a rational design strategy to achieve a reasonable iron supplement, which will guide the use of iron in animal husbandry.


Assuntos
Anemia Ferropriva/veterinária , Sobrecarga de Ferro/veterinária , Ferro da Dieta/uso terapêutico , Ferro/metabolismo , Doenças dos Suínos/prevenção & controle , Suínos/fisiologia , Anemia Ferropriva/metabolismo , Anemia Ferropriva/prevenção & controle , Animais , Homeostase , Mucosa Intestinal/metabolismo , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/prevenção & controle , Ferro da Dieta/metabolismo , Doenças dos Suínos/metabolismo , Doenças dos Suínos/patologia
8.
Biol Trace Elem Res ; 194(1): 210-220, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31236816

RESUMO

We aimed to evaluate the effect of grape seed proanthocyanidins (GSPCs) on neuronal apoptosis, particularly through their roles in maintaining divalent mineral element balance and resisting oxidation in rats with iron overload. A total of 40 Sprague-Dawley rats were randomly divided into control, iron overload, GSPCs, and iron overload + GSPCs groups. The iron, calcium, zinc, magnesium, and copper contents in the brain tissue of the rats were measured using inductively coupled plasma mass spectrometry. Their oxidative stress state was determined using the relevant kit. The number of apoptotic neurons was evaluated using the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and synaptosome numbers were determined using the immunohistochemical approach. Fas, Bax, and Bcl-2 gene expressions in the cortex and hippocampus were detected using quantitative real-time polymerase chain reaction. After 7 weeks, compared with the control group, the zinc and magnesium contents; superoxide dismutase, glutathione peroxidase, and catalase activities; and synaptophysin and Bcl-2 gene expressions in the iron overload group were significantly decreased, whereas the iron, calcium contents, and malondialdehyde contents; TUNEL-positive cell numbers; and Fas and Bax gene expressions were significantly increased. There were no significant changes in the copper content. Conversely, the rats exhibited better recovery when GSPCs were used instead of iron alone. In summary, GSPCs protected against iron overload induced neuronal apoptosis in rats by maintaining the divalent mineral element balance, reducing oxidative stress, and regulating apoptotic genes expressions.


Assuntos
Apoptose/efeitos dos fármacos , Extrato de Sementes de Uva/farmacologia , Sobrecarga de Ferro/prevenção & controle , Neurônios/efeitos dos fármacos , Proantocianidinas/farmacologia , Animais , Dieta , Extrato de Sementes de Uva/administração & dosagem , Masculino , Proantocianidinas/administração & dosagem , Ratos , Ratos Sprague-Dawley
9.
Ann Clin Lab Sci ; 49(6): 836-837, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31882437

RESUMO

Clinically, sickle cell disease (SCD) is characterized by chronic hemolytic anemia, recurrent acute vaso-occlusive crises, and progressive multi-organ failure. The management for SCD varies greatly among patients, and in the same patient longitudinally. Some patients may benefit from minimal therapy and infrequent transfusions, while others are transfusion dependent. Transfusion therapy can consist of simple transfusions, which often lead to iron overload and require iron chelation therapy. Simple transfusion, however, cannot reduce HbS levels rapidly, which may be required in certain critical conditions such as acute chest syndrome (ACS) or stroke. On the other hand, red blood cell exchange transfusion (RBCEX) can prevent iron overload and achieve rapid HbS reduction. In RBCEX, the red blood cells (RBCs) of the patient are replaced with normal RBCs, and the removed plasma is returned to the patient with minimal alteration. Plasma of patients with SCD is known to contain increased levels of several inflammatory mediators in the steady state that increase during crises. This finding explains why some patients with severe complications do not respond to RBCEX, but do much better after using plasma exchange in addition to RBCEX, as previously reported. Based on this, a revision of the indications for RBCEX in patents with SCD is recommended. DISCUSSION: In the 1980s and 1990s we used the Haemonetics Corporation's V-50 machine to perform intermittent whole blood (WB) exchange to treat severe complications of sickle cell disease (SCD.) The results were excellent, as previously described [1].


Assuntos
Anemia Falciforme/terapia , Transfusão de Eritrócitos/métodos , Anemia Falciforme/sangue , Humanos , Sobrecarga de Ferro/prevenção & controle , Troca Plasmática
10.
Transfus Med Rev ; 33(3): 170-175, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31153715

RESUMO

Sickle cell disease (SCD) is a frequent indication for chronic transfusion, which can cause iron overload. Excess iron often affects the liver, but not the heart in SCD. Magnetic resonance (MR) is recommended to detect myocardial iron overload (MIO) but its elevated cost requires optimized indication. We aimed to compile all published data on MIO in SCD upon the description of a fatal case of severe MIO in our institution, and to determine associated risk factors. We performed a systematic review using the PRISMA guidelines in two databases (PubMed and Web of Science). Inclusion criteria were publication in English, patients diagnosed with SCD, and reporting ferritin and MIO by MR. Twenty publications reported on 865 SCD adult and pediatric patients, with at least 10 other cases of MIO. The prevalence of MIO in chronically transfused SCD patients can be estimated to be 3% or less, and is associated with high transfusion burden, top-up transfusions, and low adherence to iron chelation. Cardiac siderosis in SCD is rarely reported, and increased awareness with better use of the available screening tools are necessary. Prospective studies should define the recommended chelation regimens depending on the severity of MIO.


Assuntos
Anemia Falciforme/terapia , Ferritinas/metabolismo , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/etiologia , Miocárdio/metabolismo , Reação Transfusional/diagnóstico , Anemia Falciforme/metabolismo , Biomarcadores/metabolismo , Evolução Fatal , Feminino , Humanos , Sobrecarga de Ferro/epidemiologia , Sobrecarga de Ferro/prevenção & controle , Pessoa de Meia-Idade , Reação Transfusional/epidemiologia , Reação Transfusional/prevenção & controle
11.
Crit Rev Oncol Hematol ; 141: 54-72, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31228649

RESUMO

Myelodysplastic syndromes (MDS) are clonal hematopoietic stem cell disorders characterized by cytopenias and progression to acute myeloid leukemia (AML). Although several treatments for MDS are available, the mainstay of therapy for most patients remains supportive care. This includes red blood cell (RBC) transfusion to correct anemia, which leads to iron overload. RBC transfusion dependence and iron overload portend inferior overall survival. Some studies indicate that iron chelation therapy (ICT) may have beneficial effects on clinical endpoints in MDS; however, these data are from non-randomized trials and the validity of the results is vigorously debated. A consistent observation in clinical studies of ICT in MDS has been hematologic improvement (HI) in some patients, including a reduction in RBC transfusion requirements and even transfusion independence. Here, we review data on HI with ICT in lower risk MDS, preclinical data examining mechanisms by which HI may occur, and identify areas for future investigation.


Assuntos
Terapia por Quelação , Transfusão de Eritrócitos/efeitos adversos , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/prevenção & controle , Síndromes Mielodisplásicas/terapia , Anemia/tratamento farmacológico , Anemia/etiologia , Transfusão de Sangue/métodos , Terapia por Quelação/métodos , Transfusão de Eritrócitos/métodos , Humanos , Ferro/sangue , Sobrecarga de Ferro/etiologia , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/tratamento farmacológico , Trombocitopenia/tratamento farmacológico , Trombocitopenia/etiologia , Reação Transfusional/sangue , Reação Transfusional/prevenção & controle
12.
Pak J Biol Sci ; 22(11): 510-517, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31930829

RESUMO

BACKGROUND AND OBJECTIVE: Iron is an essential element that involved in many vital physiological functions in fish, while excess iron concentration causes many toxic effects. Curcumin is a natural popular spice that used as a dietary supplementation and has iron chelating properties. This study was conducted to evaluate the effect of curcumin on iron toxicity in catfish (Clarias gariepinus). Also this study assess the antibacterial effect of curcumin against Vibrio anguillarum infection. MATERIALS AND METHODS: Clarias gariepinus were orally exposed to low and high doses of curcumin (40, 80 mg kg-1 fish) for 3 weeks. Fish were then exposed to 25 mg L-1 of ferric chloride as a source of iron toxicity for another 3 weeks. Some hematological parameters (Total and differential white blood cells count, total red blood cells count, hemoglobin concentration and hematocrit %) and biochemical parameters (Serum ferritin, transferrin, ALT, AST, protein and albumin) were assessed before and after exposure to iron. Iron residues in gills, spleen, liver, kidney, abdominal fats, gonads and muscles were also determined. Moreover the determination of fish survivability after bacterial challenge with Vibrio anguillarum was recorded. RESULTS: Iron caused decrease in total white blood cells count (WBCs), increase in ferritin level and elevation in liver function enzymes (ALT and AST). However, the pretreatment of fish with curcumin significantly increased WBCs, lymphocyte percentage, ferritin level and protein and albumin concentrations with significantly decreased transferrin, ALT and AST levels. Also there were significant decreases in iron concentration in serum, kidney, gonads and muscle in both low and high curcumin pretreated groups compared to Fe group. CONCLUSION: Results indicated a modulatory effect of curcumin against iron toxicity in catfish, also curcumin had an immune-stimulant effect against Vibrio anguillarum infection.


Assuntos
Peixes-Gato , Curcumina/administração & dosagem , Doenças dos Peixes/prevenção & controle , Ferro/toxicidade , Vibrioses/veterinária , Vibrio , Administração Oral , Animais , Antibacterianos/administração & dosagem , Suplementos Nutricionais , Feminino , Doenças dos Peixes/microbiologia , Ferro/sangue , Ferro/metabolismo , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/prevenção & controle , Sobrecarga de Ferro/veterinária , Fígado/metabolismo , Masculino , Vibrioses/microbiologia , Vibrioses/prevenção & controle , Poluentes Químicos da Água/toxicidade
13.
Semin Dial ; 32(1): 22-29, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29956370

RESUMO

Parenteral iron is used to restore the body's iron pool before and during erythropoiesis-stimulating agent (ESA) therapy; together these agents form the backbone of anemia management in end-stage renal disease (ESRD) patients undergoing hemodialysis. ESRD patients receiving chronic intravenous iron products, which exceed their blood loss are exposed to an increased risk of positive iron balance. Measurement of the liver iron concentration (LIC) reflects total body iron stores in patients with secondary hemosiderosis and genetic hemochromatosis. Recent studies of LIC in hemodialysis patients, measured by quantitative MRI and magnetic susceptometry, have demonstrated a high risk of iron overload in dialysis patients treated with IV iron products at doses advocated by current anemia management guidelines for dialysis patients. Liver iron overload causes increased production of hepcidin and elevated plasma levels, which can activate macrophages of atherosclerotic plaques. This mechanism may explain the results of 3 long-term epidemiological studies which showed the association of excessive IV iron doses with increased risk of cardiovascular morbidity and mortality among hemodialysis patients. A more physiological approach of iron therapy in ESRD is needed. Peritoneal dialysis patients, hemodialysis patients infected with hepatitis C virus, and hemodialysis patients with ferritin above 1000 µg/L without a concomitant inflammatory state, all require specific and cautious iron management. Two recent studies have shown that most hemodialysis patients will benefit from lower maintenance IV iron dosages; their results are applicable to American hemodialysis patients. Novel pharmacometric and economic approaches to iron therapy and anemia management are emerging which are designed to lessen the potential side effects of excessive IV iron while maintaining hemoglobin stability without an increase in ESA dosing.


Assuntos
Anemia Ferropriva/tratamento farmacológico , Compostos Férricos/administração & dosagem , Sobrecarga de Ferro/prevenção & controle , Diálise Renal/efeitos adversos , Administração Intravenosa , Idoso , Anemia Ferropriva/etiologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Compostos Férricos/efeitos adversos , Ferritinas/sangue , Hematínicos/administração & dosagem , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Diálise Peritoneal/efeitos adversos , Diálise Peritoneal/métodos , Prognóstico , Diálise Renal/métodos , Medição de Risco , Fatores de Tempo , Resultado do Tratamento , Suspensão de Tratamento
14.
Health Qual Life Outcomes ; 16(1): 216, 2018 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-30453981

RESUMO

BACKGROUND: Adherence to long-term chelation therapy in transfusion-dependent patients is critical to prevent iron overload-related complications. Once-daily deferasirox dispersible tablets (DT) have proven long-term efficacy and safety in patients ≥2 years old with chronic transfusional iron overload. However, barriers to optimal adherence remain, including palatability, preparation time, and requirements for fasting state. A new film-coated tablet (FCT) formulation was developed, swallowed once daily (whole/crushed) with/without a light meal. METHODS: The open-label, Phase II ECLIPSE study evaluated patient-reported outcomes (PROs) in transfusion-dependent thalassemia or lower-risk myelodysplastic syndromes patients randomized 1:1 to receive deferasirox DT or FCT over 24 weeks as a secondary outcome of the study. Three PRO questionnaires were developed to evaluate both deferasirox formulations: 1) Modified Satisfaction with Iron Chelation Therapy Questionnaire; 2) Palatability Questionnaire; 3) Gastrointestinal (GI) Symptom Diary. RESULTS: One hundred seventy three patients were enrolled; 87 received the FCT and 86 the DT formulation. FCT recipients consistently reported better adherence (easier to take medication, less bothered by time to prepare medication and waiting time before eating), greater satisfaction/preference (general satisfaction and with administration of medicine), and fewer concerns (less worry about not swallowing enough medication, fewer limitations in daily activities, less concern about side effects). FCT recipients reported no taste or aftertaste and could swallow all their medicine with an acceptable amount of liquid. GI summary scores were low for both formulations. CONCLUSIONS: These findings suggest a preference in favor of the deferasirox FCT formulation regardless of underlying disease or age group. Better patient satisfaction and adherence to chelation therapy may reduce iron overload-related complications. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02125877; registered April 26, 2014.


Assuntos
Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Síndromes Mielodisplásicas/tratamento farmacológico , Medidas de Resultados Relatados pelo Paciente , Satisfação do Paciente , Talassemia/tratamento farmacológico , Adulto , Transfusão de Sangue , Terapia por Quelação/métodos , Feminino , Humanos , Sobrecarga de Ferro/prevenção & controle , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/psicologia , Qualidade de Vida , Talassemia/psicologia
16.
Ann Hematol ; 97(10): 1925-1932, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29926157

RESUMO

We prospectively assessed by magnetic resonance imaging (MRI) the advantages of desferrioxamine (DFO) with respect to the absence of chelation therapy in non transfusion-dependent thalassaemia (NTDT) patients. We considered 18 patients non-chelated and 33 patients who received DFO alone between the two MRI scans. Iron overload was assessed by the T2* technique. Biventricular function parameters were quantified by cine sequences. No patient treated with DFO had cardiac iron. At baseline, only one non-chelated patient showed a pathological heart T2* value (< 20 ms) and he recovered at the follow-up. The percentage of patients who maintained a normal heart T2* value was 100% in both groups. A significant increase in the right ventricular ejection fraction was detected in DFO patients (3.48 ± 7.22%; P = 0.024). The changes in cardiac T2* values and in the biventricular function were comparable between the two groups. In patients with hepatic iron at baseline (MRI liver iron concentration (LIC) ≥ 3 mg/g/dw), the reduction in MRI LIC values was significant only in the DFO group (- 2.20 ± 4.84 mg/g/dw; P = 0.050). The decrease in MRI LIC was comparable between the groups. In conclusion, in NTDT patients, DFO therapy showed no advantage in terms of cardiac iron but its administration allowed an improvement in right ventricular function. Moreover, DFO reduced hepatic iron in patients with significant iron burden at baseline.


Assuntos
Terapia por Quelação , Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/prevenção & controle , Talassemia/tratamento farmacológico , Adolescente , Adulto , Idoso , Terapia por Quelação/métodos , Criança , Feminino , Seguimentos , Coração/diagnóstico por imagem , Coração/efeitos dos fármacos , Humanos , Ferro/metabolismo , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismo , Adulto Jovem
17.
Cochrane Database Syst Rev ; 5: CD012349, 2018 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-29737522

RESUMO

BACKGROUND: Regularly transfused people with sickle cell disease (SCD) and people with thalassaemia (who are transfusion-dependent or non-transfusion-dependent) are at risk of iron overload. Iron overload can lead to iron toxicity in vulnerable organs such as the heart, liver and endocrine glands; which can be prevented and treated with iron chelating agents. The intensive demands and uncomfortable side effects of therapy can have a negative impact on daily activities and well-being, which may affect adherence. OBJECTIVES: To identify and assess the effectiveness of interventions (psychological and psychosocial, educational, medication interventions, or multi-component interventions) to improve adherence to iron chelation therapy in people with SCD or thalassaemia. SEARCH METHODS: We searched CENTRAL (the Cochrane Library), MEDLINE, Embase, CINAHL, PsycINFO, Psychology and Behavioral Sciences Collection, Web of Science Science & Social Sciences Conference Proceedings Indexes and ongoing trial databases (01 February 2017). We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Haemoglobinopathies Trials Register (12 December 2017). SELECTION CRITERIA: For trials comparing medications or medication changes, only randomised controlled trials (RCTs) were eligible for inclusion.For studies including psychological and psychosocial interventions, educational Interventions, or multi-component interventions, non-RCTs, controlled before-after studies, and interrupted time series studies with adherence as a primary outcome were also eligible for inclusion. DATA COLLECTION AND ANALYSIS: Three authors independently assessed trial eligibility, risk of bias and extracted data. The quality of the evidence was assessed using GRADE. MAIN RESULTS: We included 16 RCTs (1525 participants) published between 1997 and 2017. Most participants had ß-thalassaemia major; 195 had SCD and 88 had ß-thalassaemia intermedia. Mean age ranged from 11 to 41 years. One trial was of medication management and 15 RCTs were of medication interventions. Medications assessed were subcutaneous deferoxamine, and two oral-chelating agents, deferiprone and deferasirox.We rated the quality of evidence as low to very low across all outcomes identified in this review.Three trials measured quality of life (QoL) with validated instruments, but provided no analysable data and reported no difference in QoL.Deferiprone versus deferoxamineWe are uncertain whether deferiprone increases adherence to iron chelation therapy (four trials, very low-quality evidence). Results could not be combined due to considerable heterogeneity (participants' age and different medication regimens). Medication adherence was high (deferiprone (85% to 94.9%); deferoxamine (71.6% to 93%)).We are uncertain whether deferiprone increases the risk of agranulocytosis, risk ratio (RR) 7.88 (99% confidence interval (CI) 0.18 to 352.39); or has any effect on all-cause mortality, RR 0.44 (95% CI 0.12 to 1.63) (one trial; 88 participants; very low-quality evidence).Deferasirox versus deferoxamineWe are uncertain whether deferasirox increases adherence to iron chelation therapy, mean difference (MD) -1.40 (95% CI -3.66 to 0.86) (one trial; 197 participants; very-low quality evidence). Medication adherence was high (deferasirox (99%); deferoxamine (100%)). We are uncertain whether deferasirox decreases the risk of thalassaemia-related serious adverse events (SAEs), RR 0.95 (95% CI 0.41 to 2.17); or all-cause mortality, RR 0.96 (95% CI 0.06 to 15.06) (two trials; 240 participants; very low-quality evidence).We are uncertain whether deferasirox decreases the risk of SCD-related pain crises, RR 1.05 (95% CI 0.68 to 1.62); or other SCD-related SAEs, RR 1.08 (95% CI 0.77 to 1.51) (one trial; 195 participants; very low-quality evidence).Deferasirox film-coated tablet (FCT) versus deferasirox dispersible tablet (DT)Deferasirox FCT may make little or no difference to adherence, RR 1.10 (95% CI 0.99 to 1.22) (one trial; 173 participants; low-quality evidence). Medication adherence was high (FCT (92.9%); DT (85.3%)).We are uncertain if deferasirox FCT increases the incidence of SAEs, RR 1.22 (95% CI 0.62 to 2.37); or all-cause mortality, RR 2.97 (95% CI 0.12 to 71.81) (one trial; 173 participants; very low-quality evidence).Deferiprone and deferoxamine combined versus deferiprone alone We are uncertain if deferiprone and deferoxamine combined increases adherence to iron chelation therapy (very low-quality evidence). Medication adherence was high (deferiprone 92.7% (range 37% to 100%) to 93.6% (range 56% to 100%); deferoxamine 70.6% (range 25% to 100%).Combination therapy may make little or no difference to the risk of SAEs, RR 0.15 (95% CI 0.01 to 2.81) (one trial; 213 participants; low-quality evidence).We are uncertain if combination therapy decreases all-cause mortality, RR 0.77 (95% CI 0.18 to 3.35) (two trials; 237 participants; very low-quality evidence).Deferiprone and deferoxamine combined versus deferoxamine aloneDeferiprone and deferoxamine combined may have little or no effect on adherence to iron chelation therapy (four trials; 216 participants; low-quality evidence). Medication adherence was high (deferoxamine 91.4% to 96.1%; deferiprone: 82.4%)Deferiprone and deferoxamine combined, may have little or no difference in SAEs or mortality (low-quality evidence). No SAEs occurred in three trials and were not reported in one trial. No deaths occurred in two trials and were not reported in two trials.Deferiprone and deferoxamine combined versus deferiprone and deferasirox combinedDeferiprone and deferasirox combined may improve adherence to iron chelation therapy, RR 0.84 (95% CI 0.72 to 0.99) (one trial; 96 participants; low-quality evidence). Medication adherence was high (deferiprone and deferoxamine: 80%; deferiprone and deferasirox: 95%).We are uncertain if deferiprone and deferasirox decreases the incidence of SAEs, RR 1.00 (95% CI 0.06 to 15.53) (one trial; 96 participants; very low-quality evidence).There were no deaths in the trial (low-quality evidence).Medication management versus standard careWe are uncertain if medication management improves health-related QoL (one trial; 48 participants; very low-quality evidence). Adherence was only measured in one arm of the trial. AUTHORS' CONCLUSIONS: The medication comparisons included in this review had higher than average adherence rates not accounted for by differences in medication administration or side effects.Participants may have been selected based on higher adherence to trial medications at baseline. Also, within the clinical trial context, there is increased attention and involvement of clinicians, thus high adherence rates may be an artefact of trial participation.Real-world, pragmatic trials in community and clinic settings are needed that examine both confirmed or unconfirmed adherence strategies that may increase adherence to iron chelation therapy.Due to lack of evidence this review cannot comment on intervention strategies for different age groups.


Assuntos
Anemia Falciforme/terapia , Terapia por Quelação , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/prevenção & controle , Cooperação do Paciente , Talassemia beta/prevenção & controle , Adolescente , Adulto , Anemia Falciforme/mortalidade , Benzoatos/uso terapêutico , Criança , Deferasirox , Deferiprona , Desferroxamina/uso terapêutico , Humanos , Sobrecarga de Ferro/etiologia , Piridonas/uso terapêutico , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Triazóis/uso terapêutico , Talassemia beta/mortalidade
18.
J Pediatr Hematol Oncol ; 40(3): 178-181, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29420373

RESUMO

Essential trace elements deficiency including zinc and copper are frequently reported in the literature, but the results are controversial. The aim of this study was to evaluate zinc and copper levels in thalassemia major (TM) patients who were on regular transfusion and iron chelation therapy. In a case-control cross-sectional study 43 TM patients and 43 age-matched and sex-matched healthy controls were examined. Patients were selected by convenience sampling method from TM patients who were registered in Thalassemia Clinic during 6 months. Serum zinc and copper levels were evaluated in all subjects. Zinc and copper dietary intake were also assessed. The median zinc level in the participants was significantly lower than the control group (35 [6.3 to 298] vs. 173 [3.1 to 584] µg/dL; P<0.05), but the mean copper level was significantly higher in the patients in comparison with the control group (260±118 vs. 201±69 µg/dL; P<0.05). In contrast, the mean zinc and copper dietary intake in the patient's group were significantly lower than the control group. The mean serum zinc and copper levels in the patient's group were not different according to iron chelation therapy type. Also, zinc and copper levels in the patient's group were not statistically significant based on ferritin level, age, and duration of therapy. Essential trace elements level change and deficiency might occur in TM patients. Hence, routine assessment of these elements is recommended for better management.


Assuntos
Terapia por Quelação , Cobre/sangue , Quelantes de Ferro/uso terapêutico , Zinco/sangue , Talassemia beta/terapia , Adulto , Transfusão de Sangue , Estudos de Casos e Controles , Terapia por Quelação/métodos , Estudos Transversais , Feminino , Humanos , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/prevenção & controle , Masculino , Adulto Jovem
19.
Ann Hematol ; 97(4): 679-684, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29318368

RESUMO

The impaired biosynthesis of the ß-globin chain in ß-thalassemia leads to the accumulation of unpaired alpha globin chains, failure in hemoglobin formation, and iron overload due to frequent blood transfusion. Iron excess causes oxidative stress and massive tissue injuries. Advanced glycation end products (AGEs) are harmful agents, and their production accelerates in oxidative conditions. This study was conducted on 45 patients with major ß-thalassemia who received frequent blood transfusions and chelation therapy and were compared to 40 healthy subjects. Metabolic parameters including glycemic and iron indices, hepatic and renal functions tests, oxidative stress markers, and AGEs (carboxymethyl-lysine and pentosidine) levels were measured. All parameters were significantly increased in ß-thalassemia compared to the control except for glutathione levels. Blood glucose, iron, serum ferritin, non-transferrin-bound iron (NTBI), MDA, soluble form of low-density lipoprotein receptor, glutathione peroxidase, total reactive oxygen species (ROS), and AGE levels were significantly higher in the ß-thalassemia patients. Iron and ferritin showed a significant positive correlation with pentosidine (P < 0.01) but not with carboxymethyl-lysine. The NTBI was markedly increased in the ß-thalassemia patients, and its levels correlated significantly with both carboxymethyl-lysine and pentosidine (P < 0.05). Our findings confirm the oxidative status generated by the iron overload in ß-thalassemia major patients and highlight the enhanced formation of AGEs, which may play an important role in the pathogenesis of ß-thalassemia major.


Assuntos
Transfusão de Sangue , Produtos Finais de Glicação Avançada/sangue , Sobrecarga de Ferro/etiologia , Estresse Oxidativo , Reação Transfusional/fisiopatologia , Talassemia beta/sangue , Adolescente , Adulto , Biomarcadores/sangue , Terapia por Quelação/efeitos adversos , Terapia Combinada/efeitos adversos , Estudos Transversais , Deferiprona , Desferroxamina/uso terapêutico , Feminino , Humanos , Irã (Geográfico) , Sobrecarga de Ferro/prevenção & controle , Masculino , Piridonas/uso terapêutico , Receptores Depuradores Classe E/sangue , Adulto Jovem , Talassemia beta/terapia
20.
Expert Rev Hematol ; 11(2): 109-116, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29292655

RESUMO

INTRODUCTION: Despite the availability of effective iron chelators, transfusion-related morbidity is still a challenge in chronically transfused patients with myelodysplastic syndromes (MDS). In these patients, transfusion-induced iron overload may lead to organ dysfunction or even organ failure. In addition, iron overload is associated with reduced overall survival in MDS. Areas covered: During the past 10 years, various guidelines for the management of MDS patients with iron overload have been proposed. In the present article, we provide our updated recommendations for the diagnosis, prevention and therapy of iron overload in MDS. In addition, we propose refined treatment response criteria. As in 2006 and 2007, recommendations were discussed and formulated by participants of our Austrian MDS platform in a series of meetings in 2016 and 2017. Expert commentary: Our updated recommendations should support early recognition of iron overload, optimal patient management and the measurement of clinical responses to chelation treatment in daily practice.


Assuntos
Transfusão de Sangue , Sobrecarga de Ferro , Síndromes Mielodisplásicas , Reação Transfusional , Humanos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/prevenção & controle , Síndromes Mielodisplásicas/sangue , Síndromes Mielodisplásicas/terapia , Guias de Prática Clínica como Assunto , Reação Transfusional/sangue , Reação Transfusional/prevenção & controle
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA