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1.
Blood ; 142(11): 949-960, 2023 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-37478396

RESUMO

The intricate interplay of anemia and iron overload under the pathophysiological umbrella of ineffective erythropoiesis in non-transfusion-dependent ß-thalassemia (NTDT) results in a complex variety of clinical phenotypes that are challenging to diagnose and manage. In this article, we use a clinical framework rooted in pathophysiology to present 4 common scenarios of patients with NTDT. Starting from practical considerations in the diagnosis of NTDT, we delineate our strategy for the longitudinal care of patients who exhibit different constellations of symptoms and complications. We highlight the use of transfusion therapy and novel agents, such as luspatercept, in the patient with anemia-related complications. We also describe our approach to chelation therapy in the patient with iron overload. Although tackling every specific complication of NTDT is beyond the scope of this article, we touch on the management of the various morbidities and multisystem manifestations of the disease.


Assuntos
Sobrecarga de Ferro , Talassemia , Talassemia beta , Humanos , Talassemia beta/terapia , Talassemia beta/tratamento farmacológico , Quelantes de Ferro/uso terapêutico , Talassemia/tratamento farmacológico , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/terapia , Terapia por Quelação/efeitos adversos
2.
Transfus Apher Sci ; 62(3): 103702, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37055329

RESUMO

Drug-induced nephrolithiasis can arise from insoluble components within medications or crystallization of metabolites due to changes in metabolism and urinary pH. The connection between drugs utilized for iron chelation therapy (ICT) and nephrolithiasis is not well understood. In this report, we describe two pediatric patients diagnosed with nephrolithiasis while undergoing treatment with the chelating agents deferasirox, deferiprone, and deferoxamine for iron overload secondary to repeat blood transfusion.


Assuntos
Sobrecarga de Ferro , Nefrolitíase , Talassemia beta , Humanos , Criança , Terapia por Quelação/efeitos adversos , Quelantes de Ferro/efeitos adversos , Deferasirox/efeitos adversos , Deferiprona/uso terapêutico , Desferroxamina/efeitos adversos , Benzoatos/efeitos adversos , Triazóis , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Nefrolitíase/induzido quimicamente , Nefrolitíase/complicações , Nefrolitíase/tratamento farmacológico , Ferro/uso terapêutico , Talassemia beta/terapia
3.
Hematol Oncol Clin North Am ; 37(2): 393-411, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36907611

RESUMO

Because women with transfusion-dependent thalassemia are seeking pregnancy, ensuring the best outcomes for both mother and baby require concerted and collaborative efforts between the hematologist, obstetrician, cardiologist, hepatologist, and genetic counselor among others. Proactive counseling, early fertility evaluation, optimal management of iron overload and organ function, and application of advances in reproductive technology and prenatal screening are important in ensuring a healthy outcome. Many unanswered questions remain requiring further study, including fertility preservation, non-invasive prenatal diagnosis, chelation therapy during pregnancy, and indications and duration of anticoagulation.


Assuntos
Sobrecarga de Ferro , Talassemia , Talassemia beta , Gravidez , Feminino , Humanos , Talassemia/terapia , Sobrecarga de Ferro/etiologia , Terapia por Quelação/efeitos adversos , Diagnóstico Pré-Natal/efeitos adversos , Fertilidade , Quelantes de Ferro/uso terapêutico , Talassemia beta/terapia
4.
Eur J Haematol ; 110(5): 490-497, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36708354

RESUMO

Iron overload is a pathological condition resulting from a congenital impairment of its regulation, increased intestinal iron absorption secondary to bone marrow erythroid hyperplasia, or a chronic transfusional regimen. In normal conditions, intracellular and systemic mechanisms contribute to maintaining iron balance. When this complex homeostatic mechanism fails, an iron overload could be present. Detecting an iron overload is not easy. The gold standard remains the liver biopsy, even if it is invasive and dangerous. Identifying iron using noninvasive techniques allowed a better understanding of the rate of iron overload in different organs, with a low risk for the patient. Estimating serum ferritin (mg/L) is the easiest and, consequently, the most employed diagnostic tool for assessing body iron stores, even if it could be a not specific method. The most common hematological causes of iron overload are myelodysplastic syndromes, sickle cell disease, and thalassemia. In all of these conditions, three drugs have been approved for the treatment of iron overload: deferiprone, deferoxamine, and deferasirox. These chelators have been demonstrated to help lower tissue iron levels and prevent iron overload complications, improving event-free survival (EFS). Nowadays, the decision to start chelation and which chelator to choose remains the joint decision of the clinician and patient.


Assuntos
Terapia por Quelação , Sobrecarga de Ferro , Humanos , Terapia por Quelação/efeitos adversos , Quelantes de Ferro/uso terapêutico , Deferasirox/uso terapêutico , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Piridonas/uso terapêutico , Benzoatos/uso terapêutico , Triazóis , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Ferro
5.
Rev Esp Cardiol (Engl Ed) ; 75(12): 1050-1058, 2022 Dec.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35931285

RESUMO

The environment is a strong determinant of cardiovascular health. Environmental cardiology studies the contribution of environmental exposures with the aim of minimizing the harmful influences of pollution and promoting cardiovascular health through specific preventive or therapeutic strategies. The present review focuses on particulate matter and metals, which are the pollutants with the strongest level of scientific evidence, and includes possible interventions. Legislation, mitigation and control of pollutants in air, water and food, as well as environmental policies for heart-healthy spaces, are key measures for cardiovascular health. Individual strategies include the chelation of divalent metals such as lead and cadmium, metals that can only be removed from the body via chelation. The TACT (Trial to Assess Chelation Therapy, NCT00044213) clinical trial demonstrated cardiovascular benefit in patients with a previous myocardial infarction, especially in those with diabetes. Currently, the TACT2 trial (NCT02733185) is replicating the TACT results in people with diabetes. Data from the United States and Argentina have also shown the potential usefulness of chelation in severe peripheral arterial disease. More research and action in environmental cardiology could substantially help to improve the prevention and treatment of cardiovascular disease.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Poluentes Ambientais , Infarto do Miocárdio , Humanos , Estados Unidos , Terapia por Quelação/efeitos adversos , Terapia por Quelação/métodos , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Quelantes/uso terapêutico , Diabetes Mellitus/tratamento farmacológico , Metais , Infarto do Miocárdio/complicações
6.
Hemoglobin ; 46(4): 201-213, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35930250

RESUMO

Iron chelation therapy (ICT) is essential to prevent complications of iron overload in patients with transfusion-dependent thalassemia. However, the role that adherence to ICT plays in health-related outcomes is less well known. Our objectives were to identify adherence rates of ICT, and to assess methods of measurement, predictors of adherence, and adherence-related health outcomes in the literature published between 1980 and 2020. Of 543 articles, 43 met the inclusion criteria. Studies measured ICT adherence, predictors, and/or outcomes associated with adherence. Most studies were across multiple countries in Europe and North America (n = 8/43, 18.6%), recruited in clinics (n = 39/43, 90.7%), and focused on ß-thalassemia (ß-thal) (n = 25/43, 58.1%). Common methods of assessing ICT adherence included patient self-report (n = 24/43, 55.8%), pill count (n = 9/43, 20.9%), prescription refill history (n = 3/43, 7.0%), provider scoring (n = 3/43, 7.0%), and combinations of methods (n = 4/43, 9.3%). Studies reported adherence either in 'categories' with different levels of adherence (n = 24) or 'quantitatively' as a percentage of doses of medication taken out of those prescribed (n = 17). Adherence levels varied (median 91.7%, range 42.0-99.97%). Studies varied in sample size and methods of adherence assessment and reporting, which prohibited meta-analysis. Due to a lack of consensus on how adherence is defined, it is difficult to compare ICT adherence reporting. Further research is needed to establish guidelines for assessing adherence and identifying suboptimal adherence. Behavioral digital interventions have the potential to optimize ICT adherence and health outcomes.


Assuntos
Sobrecarga de Ferro , Talassemia , Talassemia beta , Adulto , Humanos , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Terapia por Quelação/efeitos adversos , Ferro , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Adesão à Medicação , Talassemia/complicações , Talassemia/tratamento farmacológico
7.
Ann Med ; 54(1): 326-342, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35103514

RESUMO

INTRODUCTION: Iron chelation therapy (ICT) is essential to prevent complications of iron overload in patients with transfusion-dependent thalassaemia. However, there is currently no standard for how to best measure adherence to ICT, nor what level of adherence necessitates concern for poor outcomes, especially in paediatric patients. The objectives of this review are to identify rates of adherence to ICT, predictors of adherence, methods of measurement, and adherence-related health outcomes in children and adolescents. METHODS: This review covers the literature published between 1980 and 2020 on ICT in thalassaemia that assessed adherence or compliance. Included studies reflect original research. The preferred reporting items of systematic reviews and meta-analyses (PRISMA) guidelines were followed for reporting results, and the findings were critically appraised with the Oxford Centre for Evidence-based Medicine criteria. RESULTS: Of the 543 articles, 37 met the inclusion criteria. The most common methods of assessing adherence included patient self-report (n = 15/36, 41.7%), and pill count (n = 15/36, 41.7%), followed by subcutaneous medication monitoring (5/36, 13.8%) and prescription refills (n = 4/36, 11.1%). Study sizes ranged from 7 to 1115 participants. Studies reported adherence either in "categories" with different levels of adherence (n = 29) or "quantitatively" as a percentage of medication taken out of those prescribed (n = 7). Quantitatively, the percentage of adherence varied from 57% to 98.4% with a median of 89.5%. Five studies focussed on interventions, four of which were designed to improve adherence. Studies varied in sample size and methods of assessment, which prohibited performing a meta-analysis. CONCLUSIONS: Due to a lack of clinical consensus on how adherence is defined, it is difficult to compare adherence to ICT in different studies. Future studies should be aimed at creating guidelines for assessing adherence and identifying suboptimal adherence. These future efforts will be crucial in informing evidence-based interventions to improve adherence and health outcomes in thalassaemia patients.Key messagesPredictive factors associated with ICT adherence in the paediatric population include age, social perception of ICT, social support, and side effects/discomfort.Increased adherence in the paediatric population is associated with decreased serum ferritin and improved cardiac, hepatic, and endocrine outcomes.Inadequate adherence to ICT is associated with increased lifetime health costs.There are few studies that focussed on interventions to increase adherence in the paediatric population, and the studies that do exist all focussed on different types of interventions; successful interventions focussed on consistent, long-term engagement with patients.


Assuntos
Terapia por Quelação , Sobrecarga de Ferro , Talassemia , Adolescente , Terapia por Quelação/efeitos adversos , Criança , Humanos , Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Cooperação do Paciente , Talassemia/complicações , Talassemia/tratamento farmacológico
8.
Vox Sang ; 117(5): 733-737, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35014065

RESUMO

BACKGROUND AND OBJECTIVES: Patients with thalassaemia experience complications related to iron overload. In Australia currently, the two main options for iron chelation are deferasirox and deferoxamine. Optimal iron chelation using monotherapy can be limited due to toxicity or tolerability. Dual chelation therapy (DCT) may provide more aggressive iron chelation. MATERIAL AND METHODS: A retrospective, observational study was performed on a state-wide referral centre for patients receiving red cell transfusions for haemoglobinopathies (Monash Health, Australia). All patients prescribed DCT were identified using a local pharmacy dispensing database and were included in the study. Pre-DCT initiation and post-DCT completion were correlated with serum ferritin, cardiac iron loading (based on MRI T2* measurements) and liver iron content (LIC) using Wilcoxon signed-rank test. RESULTS: A total of 18 patients (12 adults, 6 children) were identified as receiving DCT. All patients received a combination of deferasirox and deferoxamine. The median duration of therapy was 23 months (range 2-73). Median serum ferritin reduced by 42% (p = 0.004) and there was a 76% reduction in LIC (p = 0.062). No significant changes were seen in cardiac iron loading. CONCLUSION: DCT over a prolonged period is effective at reducing serum ferritin and may contribute to improvement in liver iron loading.


Assuntos
Sobrecarga de Ferro , Talassemia beta , Adulto , Benzoatos/uso terapêutico , Terapia por Quelação/efeitos adversos , Criança , Deferasirox/uso terapêutico , Desferroxamina/uso terapêutico , Ferritinas , Humanos , Ferro/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Estudos Retrospectivos , Triazóis/uso terapêutico , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico
9.
Ann Hematol ; 101(3): 533-539, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34981144

RESUMO

Patients with sickle cell disease (SCD) who undergo repeated blood transfusions often develop iron overload. Deferiprone (Ferriprox®) is an oral iron chelator indicated for the treatment of transfusional iron overload due to thalassemia syndromes and has been recently approved as a treatment for iron overload in adult and pediatric patients with SCD and other anemias. The present study aims to characterize the pharmacokinetic (PK) profile of deferiprone (DFP) in adult subjects with SCD. In this phase I, open-label study, subjects with SCD were administered a single 1500 mg dose of DFP. Blood and urine samples were collected for PK assessments of DFP and its main metabolite, deferiprone 3-O-glucuronide (DFP-G). Eight subjects were enrolled and completed the study. Following drug administration, serum levels of DFP and DFP-G rose to maximum concentrations at 1.0 and 2.8 h post-dose, respectively. The half-lives of DFP and DFP-G were 1.5 and 1.6 h, respectively. The majority of administered drug was metabolized and excreted as DFP-G, with less than 4% excreted unchanged in urine up to 10 h post-dose. Subjects received a safety assessment 7 (± 3) days post-dose. Two subjects reported mild adverse events unrelated to the study drug, and no other safety concerns were reported. The PK profile of DFP in SCD subjects is consistent with previous reports in healthy adult volunteers, suggesting no special dosing adjustments are indicated for this population. These findings provide valuable insight for treating iron overload in patients with SCD, who have limited chelation therapy treatment options (trial registration number: NCT01835496, date of registration: April 19, 2013).


Assuntos
Anemia Falciforme/complicações , Deferiprona/farmacocinética , Quelantes de Ferro/farmacocinética , Sobrecarga de Ferro/tratamento farmacológico , Adulto , Anemia Falciforme/terapia , Transfusão de Sangue , Terapia por Quelação/efeitos adversos , Deferiprona/efeitos adversos , Deferiprona/uso terapêutico , Feminino , Humanos , Quelantes de Ferro/efeitos adversos , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/etiologia , Masculino , Adulto Jovem
10.
Haematologica ; 107(2): 467-477, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33406815

RESUMO

Transfusion-dependent patients typically develop iron-induced cardiomyopathy, liver disease, and endocrine complications. We aimed to estimate the incidence of endocrine disorders in transfusiondependent thalassemia (TDT) patients during long-term iron-chelation therapy with deferasirox (DFX). We developed a multi-center follow-up study of 426 TDT patients treated with once-daily DFX for a median duration of 8 years, up to 18.5 years. At baseline, 118, 121, and 187 patients had 0, 1, or ≥2 endocrine diseases respectively. 104 additional endocrine diseases were developed during the follow-up. The overall risk of developing a new endocrine complication within 5 years was 9.7% (95% Confidence Interval [CI]: 6.3-13.1). Multiple Cox regression analysis identified three key predictors: age showed a positive log-linear effect (adjusted hazard ratio [HR] for 50% increase 1.2, 95% CI: 1.1-1.3, P=0.005), the serum concentration of thyrotropin showed a positive linear effect (adjusted HR for 1 mIU/L increase 1.3, 95% CI: 1.1-1.4, P<0.001) regardless the kind of disease incident, while the number of previous endocrine diseases showed a negative linear effect: the higher the number of diseases at baseline the lower the chance of developing further diseasess (adjusted HR for unit increase 0.5, 95% CI: 0.4-0.7, P<0.001). Age and thyrotropin had similar effect sizes across the categories of baseline diseases. The administration of levothyroxine as a covariate did not change the estimates. Although in DFX-treated TDT patients the risk of developing an endocrine complication is generally lower than the previously reported risk, there is considerable risk variation and the burden of these complications remains high. We developed a simple risk score chart enabling clinicians to estimate their patients' risk. Future research will look at increasing the amount of variation explained from our model and testing further clinical and laboratory predictors, including the assessment of direct endocrine magnetic resonance imaging.


Assuntos
Sobrecarga de Ferro , Talassemia , Talassemia beta , Benzoatos/efeitos adversos , Terapia por Quelação/efeitos adversos , Deferasirox/efeitos adversos , Seguimentos , Humanos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/epidemiologia , Sobrecarga de Ferro/etiologia , Medição de Risco , Fatores de Risco , Talassemia/complicações , Talassemia/epidemiologia , Talassemia/terapia , Triazóis/efeitos adversos , Talassemia beta/complicações
12.
Int J Mol Sci ; 21(22)2020 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-33233561

RESUMO

Thalassemia syndromes are characterized by the inability to produce normal hemoglobin. Ineffective erythropoiesis and red cell transfusions are sources of excess iron that the human organism is unable to remove. Iron that is not saturated by transferrin is a toxic agent that, in transfusion-dependent patients, leads to death from iron-induced cardiomyopathy in the second decade of life. The availability of effective iron chelators, advances in the understanding of the mechanism of iron toxicity and overloading, and the availability of noninvasive methods to monitor iron loading and unloading in the liver, heart, and pancreas have all significantly increased the survival of patients with thalassemia. Prolonged exposure to iron toxicity is involved in the development of endocrinopathy, osteoporosis, cirrhosis, renal failure, and malignant transformation. Now that survival has been dramatically improved, the challenge of iron chelation therapy is to prevent complications. The time has come to consider that the primary goal of chelation therapy is to avoid 24-h exposure to toxic iron and maintain body iron levels within the normal range, avoiding possible chelation-related damage. It is very important to minimize irreversible organ damage to prevent malignant transformation before complications set in and make patients ineligible for current and future curative therapies. In this clinical case-based review, we highlight particular aspects of the management of iron overload in patients with beta-thalassemia syndromes, focusing on our own experience in treating such patients. We review the pathophysiology of iron overload and the different ways to assess, quantify, and monitor it. We also discuss chelation strategies that can be used with currently available chelators, balancing the need to keep non-transferrin-bound iron levels to a minimum (zero) 24 h a day, 7 days a week and the risk of over-chelation.


Assuntos
Desferroxamina/administração & dosagem , Quelantes de Ferro/administração & dosagem , Sobrecarga de Ferro/tratamento farmacológico , Ferro/metabolismo , Reação Transfusional/complicações , Talassemia beta/terapia , Adulto , Transfusão de Sangue , Cardiomiopatias/sangue , Cardiomiopatias/etiologia , Cardiomiopatias/fisiopatologia , Cardiomiopatias/prevenção & controle , Terapia por Quelação/efeitos adversos , Terapia por Quelação/métodos , Desferroxamina/efeitos adversos , Monitoramento de Medicamentos/instrumentação , Monitoramento de Medicamentos/métodos , Feminino , Coração/efeitos dos fármacos , Coração/fisiopatologia , Humanos , Ferro/toxicidade , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/sangue , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/fisiopatologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Pâncreas/efeitos dos fármacos , Pâncreas/metabolismo , Pâncreas/patologia , Transferrina/metabolismo , Reação Transfusional/sangue , Reação Transfusional/fisiopatologia , Talassemia beta/metabolismo , Talassemia beta/patologia
13.
Cochrane Database Syst Rev ; 6: CD013165, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32588430

RESUMO

BACKGROUND: Hyperkalaemia is a common electrolyte abnormality caused by reduced renal potassium excretion in patients with chronic kidney diseases (CKD). Potassium binders, such as sodium polystyrene sulfonate and calcium polystyrene sulfonate, are widely used but may lead to constipation and other adverse gastrointestinal (GI) symptoms, reducing their tolerability. Patiromer and sodium zirconium cyclosilicate are newer ion exchange resins for treatment of hyperkalaemia which may cause fewer GI side-effects. Although more recent studies are focusing on clinically-relevant endpoints such as cardiac complications or death, the evidence on safety is still limited. Given the recent expansion in the available treatment options, it is appropriate to review the evidence of effectiveness and tolerability of all potassium exchange resins among people with CKD, with the aim to provide guidance to consumers, practitioners, and policy-makers. OBJECTIVES: To assess the benefits and harms of potassium binders for treating chronic hyperkalaemia among adults and children with CKD. SEARCH METHODS: We searched the Cochrane Kidney and Transplant Register of Studies up to 10 March 2020 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov. SELECTION CRITERIA: Randomised controlled trials (RCTs) and quasi-randomised controlled studies (quasi-RCTs) evaluating potassium binders for chronic hyperkalaemia administered in adults and children with CKD. DATA COLLECTION AND ANALYSIS: Two authors independently assessed risks of bias and extracted data. Treatment estimates were summarised by random effects meta-analysis and expressed as relative risk (RR) or mean difference (MD), with 95% confidence interval (CI). Evidence certainty was assessed using GRADE processes. MAIN RESULTS: Fifteen studies, randomising 1849 adult participants were eligible for inclusion. Twelve studies involved participants with CKD (stages 1 to 5) not requiring dialysis and three studies were among participants treated with haemodialysis. Potassium binders included calcium polystyrene sulfonate, sodium polystyrene sulfonate, patiromer, and sodium zirconium cyclosilicate. A range of routes, doses, and timing of drug administration were used. Study duration varied from 12 hours to 52 weeks (median 4 weeks). Three were cross-over studies. The mean study age ranged from 53.1 years to 73 years. No studies evaluated treatment in children. Some studies had methodological domains that were at high or unclear risks of bias, leading to low certainty in the results. Studies were not designed to measure treatment effects on cardiac arrhythmias or major GI symptoms. Ten studies (1367 randomised participants) compared a potassium binder to placebo. The certainty of the evidence was low for all outcomes. We categorised treatments in newer agents (patiromer or sodium zirconium cyclosilicate) and older agents (calcium polystyrene sulfonate and sodium polystyrene sulfonate). Patiromer or sodium zirconium cyclosilicate may make little or no difference to death (any cause) (4 studies, 688 participants: RR 0.69, 95% CI 0.11, 4.32; I2 = 0%; low certainty evidence) in CKD. The treatment effect of older potassium binders on death (any cause) was unknown. One cardiovascular death was reported with potassium binder in one study, showing that there was no difference between patiromer or sodium zirconium cyclosilicate and placebo for cardiovascular death in CKD and HD. There was no evidence of a difference between patiromer or sodium zirconium cyclosilicate and placebo for health-related quality of life (HRQoL) at the end of treatment (one study) in CKD or HD. Potassium binders had uncertain effects on nausea (3 studies, 229 participants: RR 2.10, 95% CI 0.65, 6.78; I2 = 0%; low certainty evidence), diarrhoea (5 studies, 720 participants: RR 0.84, 95% CI 0.47, 1.48; I2 = 0%; low certainty evidence), and vomiting (2 studies, 122 participants: RR 1.72, 95% CI 0.35 to 8.51; I2 = 0%; low certainty evidence) in CKD. Potassium binders may lower serum potassium levels (at the end of treatment) (3 studies, 277 participants: MD -0.62 mEq/L, 95% CI -0.97, -0.27; I2 = 92%; low certainty evidence) in CKD and HD. Potassium binders had uncertain effects on constipation (4 studies, 425 participants: RR 1.58, 95% CI 0.71, 3.52; I2 = 0%; low certainty evidence) in CKD. Potassium binders may decrease systolic blood pressure (BP) (2 studies, 369 participants: MD -3.73 mmHg, 95%CI -6.64 to -0.83; I2 = 79%; low certainty evidence) and diastolic BP (one study) at the end of the treatment. No study reported outcome data for cardiac arrhythmias or major GI events. Calcium polystyrene sulfonate may make little or no difference to serum potassium levels at end of treatment, compared to sodium polystyrene sulfonate (2 studies, 117 participants: MD 0.38 mEq/L, 95% CI -0.03 to 0.79; I2 = 42%, low certainty evidence). There was no evidence of a difference in systolic BP (one study), diastolic BP (one study), or constipation (one study) between calcium polystyrene sulfonate and sodium polystyrene sulfonate. There was no difference between high-dose and low-dose patiromer for death (sudden death) (one study), stroke (one study), myocardial infarction (one study), or constipation (one study). The comparative effects whether potassium binders were administered with or without food, laxatives, or sorbitol, were very uncertain with insufficient data to perform meta-analysis. AUTHORS' CONCLUSIONS: Evidence supporting clinical decision-making for different potassium binders to treat chronic hyperkalaemia in adults with CKD is of low certainty; no studies were identified in children. Available studies have not been designed to measure treatment effects on clinical outcomes such as cardiac arrhythmias or major GI symptoms. This review suggests the need for a large, adequately powered study of potassium binders versus placebo that assesses clinical outcomes of relevance to patients, clinicians and policy-makers. This data could be used to assess cost-effectiveness, given the lack of definitive studies and the clinical importance of potassium binders for chronic hyperkalaemia in people with CKD.


Assuntos
Quelantes/uso terapêutico , Terapia por Quelação/métodos , Hiperpotassemia/tratamento farmacológico , Potássio , Insuficiência Renal Crônica/complicações , Idoso , Causas de Morte , Quelantes/efeitos adversos , Terapia por Quelação/efeitos adversos , Doença Crônica , Humanos , Hiperpotassemia/etiologia , Hiperpotassemia/mortalidade , Pessoa de Meia-Idade , Polímeros/efeitos adversos , Polímeros/uso terapêutico , Poliestirenos/efeitos adversos , Poliestirenos/uso terapêutico , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Silicatos/efeitos adversos , Silicatos/uso terapêutico
14.
J Pediatr Orthop ; 40(6): e473-e478, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32501918

RESUMO

BACKGROUND: Arthropathies and bone deformities are well known to occur in patients with thalassemia major and have been attributed to the disease or to its therapy. Before the advent of chelation therapy, these children developed widened diploic space and "hair-on-end" pattern in skull, "cobweb" pattern in the pelvis, and the lack of the normal concave outline in the long bones because of extensive marrow proliferation. After the introduction of iron-chelation therapy, these patients were noted to develop metaphyseal abnormalities and vertebral changes resembling spondylo-metaphyseal dysplasia. Only one study has shown some association of deferiprone (chelating agent) use with distal ulnar changes in these children. Our study was done to describe the skeletal changes and deformities in wrist joints of children with transfusion-dependent thalassemia and correlate them with age, mean pretransfusion hemoglobin level, mean serum ferritin level, and type and duration of chelation therapy in these children. METHODS: A total of 60 children with transfusion-dependent thalassemia from the thalassemia daycare center were examined. These children were divided into 3 groups on the basis of their age (group A: 2 to 6 y, group B: 6 to 10 y, and group C: 10 to 14 y). Detailed history, including treatment history, number of blood transfusions received over the last 1 year, clinical examination, and radiologic assessment of both forearm with wrists were done. RESULTS: The clinical and radiologic differences in radial and ulnar lengths increased significantly with the increasing age of these patients, the ulna being short. There was some correlation between increasing negative ulnar variance and distal radial articular angle with deferiprone consumption. CONCLUSION: Chelation therapy, particularly with deferiprone, may cause distal ulnar growth arrest causing ulnar shortening and progressive radial bowing in these children. LEVEL OF EVIDENCE: Level IV-case series.


Assuntos
Terapia por Quelação/efeitos adversos , Deferiprona/efeitos adversos , Quelantes de Ferro/efeitos adversos , Articulação do Punho/efeitos dos fármacos , Talassemia beta/tratamento farmacológico , Adolescente , Transfusão de Sangue , Criança , Pré-Escolar , Feminino , Antebraço/diagnóstico por imagem , Humanos , Artropatias/etiologia , Masculino , Radiografia , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/efeitos dos fármacos , Ulna/diagnóstico por imagem , Ulna/efeitos dos fármacos , Punho/diagnóstico por imagem , Articulação do Punho/diagnóstico por imagem
15.
Taiwan J Obstet Gynecol ; 59(1): 120-122, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32039778

RESUMO

OBJECTIVE: To report cases of use of chelation therapy during pregnancy which resulted in favorable outcomes for the babies. MATERIALS AND METHODS: In this retrospective cohort study, we described the evolution and outcome of 9 pregnancies in Italian thalassemic women who received deferoxamine (DFO) inadvertently during early pregnancy. RESULTS: The use of deferoxamine during first trimester did not lead to adverse effects on the fetus or cause major complications for the gestation, although an increase in iron burden was observed after suspending chelation therapy. CONCLUSION: In our experience, iron-chelation therapy might be administrated in pregnancy where the benefits to the mother outweigh the potential risks to the baby.


Assuntos
Terapia por Quelação/efeitos adversos , Desferroxamina/efeitos adversos , Exposição Materna/efeitos adversos , Complicações Hematológicas na Gravidez/tratamento farmacológico , Sideróforos/efeitos adversos , Talassemia beta/tratamento farmacológico , Adulto , Desferroxamina/administração & dosagem , Feminino , Humanos , Nascido Vivo , Troca Materno-Fetal/efeitos dos fármacos , Gravidez , Primeiro Trimestre da Gravidez , Estudos Retrospectivos , Sideróforos/administração & dosagem
16.
Indian Pediatr ; 56(1): 41-44, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30806360

RESUMO

OBJECTIVE: To describe a novel wrist deformity in b-thalassemia major patients, and their radiographic and magnetic resonance imaging findings. METHODS: 30 patients with b-thalassemia major who were noticed to have ulnar deviation at wrist joint were evaluated for previous history of medications, serum ferritin levels, presence of pain and swelling at the wrist joint, and the duration of iron chelation therapy. Radiographs of wrist and limited magnetic resonance imaging (MRI) sequences were obtained in 30 and 15 patients, respectively. RESULTS: Radiographs revealed varying severity of distal ulnar shortening, distal radial slanting and presence of soft tissue distal to the ulna. MRI showed similar deformities along with abnormal marrow signal at distal ulnar ends; in 8 patients, a soft tissue distal to the distal end of ulna was noted. CONCLUSIONS: Varying severity of radiological abnormalities, predominantly affecting the distal ulna, are present in children and adolescents with b-thalassemia receiving oral chelation therapy.


Assuntos
Terapia por Quelação/efeitos adversos , Quelantes de Ferro/efeitos adversos , Artropatias , Punho , Talassemia beta/tratamento farmacológico , Adolescente , Criança , Feminino , Humanos , Ferro , Quelantes de Ferro/uso terapêutico , Artropatias/induzido quimicamente , Artropatias/diagnóstico por imagem , Artropatias/patologia , Masculino , Ulna/diagnóstico por imagem , Ulna/efeitos dos fármacos , Ulna/patologia , Punho/diagnóstico por imagem , Punho/patologia
17.
Hemoglobin ; 42(3): 213-216, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-30251901

RESUMO

A 20-year-old male affected by transfusion-dependent ß-thalassemia (ß-thal), was prescribed intensive chelation therapy with deferoxamine (DFO) and deferiprone (DFP) because of severe hepatic and cardiac iron overload and ß-blocker and warfarin to manage a previous event of atrial fibrillation (AFib) and heart failure. After a few months, he developed critical liver failure, renal tubulopathy and severe electrolyte imbalance. Laboratory and instrumental evaluations were performed to carry out differential diagnosis of acute liver failure and an exclusion diagnosis of drug induced liver injury (DILI) was made. The cholestatic pattern suggested warfarin as the main causative agent and polypharmacy, liver iron overload and heart failure as aggravating factors. Warfarin is a drug commonly prescribed in thalassemia patients who often need polypharmacy for the management of anemia- and iron-related complications. Strict monitoring and multidisciplinary approaches are mandatory to avoid preventable mortality in this fragile population.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/etiologia , Sobrecarga de Ferro/complicações , Talassemia beta/complicações , Antagonistas Adrenérgicos beta , Terapia por Quelação/efeitos adversos , Doença Hepática Induzida por Substâncias e Drogas/diagnóstico , Estado Terminal , Deferiprona , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Sobrecarga de Ferro/tratamento farmacológico , Masculino , Varfarina , Adulto Jovem , Talassemia beta/terapia
18.
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
19.
Transfus Clin Biol ; 25(1): 14-18, 2018 Feb.
Artigo em Francês | MEDLINE | ID: mdl-29199112

RESUMO

AIM: Our objectives were to assess the management of patients with major thalassemia and identify the various complications and monitoring means. PATIENTS AND METHODS: A retrospective study was conducted on 26 ß-thalassemic patients in the department of paediatrics, Hédi Chaker hospital, Sfax, Tunisia during a period of 25 years (from 1 January 1990 to 31 December 2014). RESULTS: The mean age of the beginning of transfusion was 11.5 months. That was with phenotyped red blood cells but not leukodepleted blood. Twenty-three patients received chelation. Before 2001, all patients received deferoxamine, poor adherence to this treatment was observed in 66% of cases. It was replaced by deferiprone since 2006 and deferasirox since 2009. A combination of 2 or 3 chelators was indicated for four patients. A total splenectomy was performed in 10 cases patients; it was due to hypersplenism. The bone marrow transplant was performed for one patient at the age of 9 year but it was rejected. Many complications were detected: endocrine complications (19 cases), immune complications (9 cases), gallbladder stones (5 cases), cardiac complications (4 cases), osteoporosis (3 cases), infectious complications (3 cases) and thromboembolic complications (2 cases). We noted some side effects related to chelation therapy in twelve cases. Four patients were dead. CONCLUSION: Improving the medical care of homozygous ß-thalassemic children requires adherence to transfusion regimen and chelation therapy. Bone marrow transplantation remains the only possible curative therapy, which must be promoted in our country.


Assuntos
Talassemia beta/terapia , Tipagem e Reações Cruzadas Sanguíneas/estatística & dados numéricos , Transfusão de Sangue/estatística & dados numéricos , Terapia por Quelação/efeitos adversos , Terapia por Quelação/estatística & dados numéricos , Pré-Escolar , Terapia Combinada , Gerenciamento Clínico , Feminino , Departamentos Hospitalares , Hospitais Urbanos/estatística & dados numéricos , Humanos , Lactente , Quelantes de Ferro/efeitos adversos , Quelantes de Ferro/uso terapêutico , Procedimentos de Redução de Leucócitos/estatística & dados numéricos , Masculino , Pediatria , Estudos Retrospectivos , Esplenectomia/estatística & dados numéricos , Reação Transfusional , Tunísia , Talassemia beta/tratamento farmacológico
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