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1.
Ann Hematol ; 103(6): 1887-1896, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38581547

RESUMO

We evaluated the impact of the genotype on clinical and hematochemical features, hepatic and cardiac iron levels, and endocrine, hepatic, and cardiovascular complications in non-transfusion-dependent (NTD) ß-thalassemia intermedia (TI) patients. Sixty patients (39.09 ± 11.11 years, 29 females) consecutively enrolled in the Myocardial Iron Overload in Thalassemia project underwent Magnetic Resonance Imaging to quantify iron overload, biventricular function parameters, and atrial areas and to detect replacement myocardial fibrosis. Three groups of patients were identified: homozygous ß+ (N = 18), heterozygous ß0ß+ (N = 22), and homozygous ß0 (N = 20). The groups were homogeneous for sex, age, splenectomy, hematochemical parameters, chelation therapy, and iron levels. The homozygous ß° genotype was associated with significantly higher biventricular end-diastolic and end-systolic volume indexes and bi-atrial area indexes. No difference was detected in biventricular ejection fractions or myocardial fibrosis. Extramedullary hematopoiesis and leg ulcers were significantly more frequent in the homozygous ß° group compared to the homozygous ß+ group. No association was detected between genotype and liver cirrhosis, hypogonadism, hypothyroidism, osteoporosis, heart failure, arrhythmias, and pulmonary hypertension. Heart remodelling related to a high cardiac output state cardiomyopathy, extramedullary hematopoiesis, and leg ulcers were more pronounced in patients with the homozygous ß° genotype compared to the other genotypes analyzed. The knowledge of the genotype can assist in the clinical management of NTD ß-TI patients.


Assuntos
Genótipo , Sobrecarga de Ferro , Ferro , Talassemia beta , Humanos , Talassemia beta/genética , Talassemia beta/complicações , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Sobrecarga de Ferro/genética , Sobrecarga de Ferro/etiologia , Ferro/metabolismo , Úlcera da Perna/etiologia , Úlcera da Perna/genética , Hematopoese Extramedular/genética , Imageamento por Ressonância Magnética , Miocárdio/patologia , Miocárdio/metabolismo , Cirrose Hepática/genética , Cirrose Hepática/complicações , Homozigoto
2.
Br J Haematol ; 204(5): 2049-2056, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38343073

RESUMO

Iron overload from repeated transfusions has a negative impact on cardiac function, and iron chelation therapy may help prevent cardiac dysfunction in transfusion-dependent patients with myelodysplastic syndromes (MDS). TELESTO (NCT00940602) was a prospective, placebo-controlled, randomised study to evaluate the iron chelator deferasirox in patients with low- or intermediate-1-risk MDS and iron overload. Echocardiographic parameters were collected at screening and during treatment. Patients receiving deferasirox experienced a significant decrease in the composite risk of hospitalisation for congestive heart failure (CHF) or worsening of cardiac function (HR = 0.23; 95% CI: 0.05, 0.99; nominal p = 0.0322) versus placebo. No significant differences between the arms were found in left ventricular ejection fraction, ventricular diameter and mass or pulmonary artery pressure. The absolute number of events was low, but the enrolled patients were younger than average for patients with MDS, with no serious cardiac comorbidities and a modest cardiovascular risk profile. These results support the effectiveness of deferasirox in preventing cardiac damage caused by iron overload in this patient population. Identification of patients developing CHF is challenging due to the lack of distinctive echocardiographic features. The treatment of iron overload may be important to prevent cardiac dysfunction in these patients, even those with moderate CHF risk.


Assuntos
Deferasirox , Quelantes de Ferro , Sobrecarga de Ferro , Síndromes Mielodisplásicas , Humanos , Deferasirox/uso terapêutico , Síndromes Mielodisplásicas/terapia , Síndromes Mielodisplásicas/tratamento farmacológico , Síndromes Mielodisplásicas/complicações , Masculino , Feminino , Quelantes de Ferro/uso terapêutico , Pessoa de Meia-Idade , Idoso , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/tratamento farmacológico , Estudos Prospectivos , Benzoatos/uso terapêutico , Benzoatos/efeitos adversos , Insuficiência Cardíaca/etiologia , Reação Transfusional/etiologia , Ecocardiografia , Adulto , Idoso de 80 Anos ou mais , Triazóis/uso terapêutico , Triazóis/efeitos adversos , Transfusão de Sangue
3.
Blood Rev ; 64: 101165, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38182489

RESUMO

α-Thalassemia is an inherited blood disorder characterized by decreased synthesis of α-globin chains that results in an imbalance of α and ß globin and thus varying degrees of ineffective erythropoiesis, decreased red blood cell (RBC) survival, chronic hemolytic anemia, and subsequent comorbidities. Clinical presentation varies depending on the genotype, ranging from a silent or mild carrier state to severe, transfusion-dependent or lethal disease. Management of patients with α-thalassemia is primarily supportive, addressing either symptoms (eg, RBC transfusions for anemia), complications of the disease, or its transfusion-dependence (eg, chelation therapy for iron overload). Several novel therapies are also in development, including curative gene manipulation techniques and disease modifying agents that target ineffective erythropoiesis and chronic hemolytic anemia. This review of α-thalassemia and its various manifestations provides practical information for clinicians who practice beyond those regions where it is found with high frequency.


Assuntos
Doenças Hematológicas , Sobrecarga de Ferro , Talassemia alfa , Talassemia beta , Humanos , Talassemia beta/terapia , Talassemia alfa/diagnóstico , Talassemia alfa/genética , Talassemia alfa/terapia , Eritropoese , Transfusão de Eritrócitos , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/terapia
4.
Auris Nasus Larynx ; 51(2): 271-275, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37903661

RESUMO

OBJECTIVE: The role of iron chelation in causing hearing loss (HL) is still unclear. The present study assessed the prevalence of HL among transfusion-dependent thalassemia (TDT) patients who underwent audiological follow-up over a 20-year period. METHODS: We retrospectively analyzed clinical records and audiological tests from January 1990 (T0) to December 2022 (T22) of a group of TDT patients who received iron chelation therapy with deferoxamine (DFO), deferiprone (DFP) or deferasirox (DFX), in monotherapy or as part of combination therapy. RESULTS: A total of 42 adult TDT patients (18 male, 24 female; age range: 41-55 years; mean age: 49.2 ± 3.7 years) were included in the study. At the T22 assessment, the overall prevalence of sensorineural HL was 23.8 % (10/42). When patients were stratified into two groups, with and without ototoxicity, no differences were observed for sex, age, BMI, creatinine level, pre-transfusional hemoglobin, start of transfusions, cardiac or hepatic T2 MRI; only ferritin serum values and duration of chelation were significantly higher (p = 0.02 and p = 0.01, respectively) in patients with hearing impairment in comparison to those with normal hearing. CONCLUSION: This study with long-term follow-up suggests that iron chelation therapy might induce ototoxicity; therefore, a long and accurate audiological follow-up should be performed in TDT patients.


Assuntos
Sobrecarga de Ferro , Ototoxicidade , Talassemia beta , Adulto , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Talassemia beta/complicações , Talassemia beta/tratamento farmacológico , Talassemia beta/epidemiologia , Deferasirox/uso terapêutico , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/epidemiologia , Sobrecarga de Ferro/etiologia , Seguimentos , Estudos Retrospectivos , Ototoxicidade/complicações , Ototoxicidade/tratamento farmacológico , Benzoatos/uso terapêutico , Triazóis/uso terapêutico , Piridonas/uso terapêutico , Quelantes de Ferro/uso terapêutico , Ferro/uso terapêutico , Audição
5.
Int J Mol Sci ; 24(23)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38069073

RESUMO

The design of clinical protocols and the selection of drugs with appropriate posology are critical parameters for therapeutic outcomes. Optimal therapeutic protocols could ideally be designed in all diseases including for millions of patients affected by excess iron deposition (EID) toxicity based on personalised medicine parameters, as well as many variations and limitations. EID is an adverse prognostic factor for all diseases and especially for millions of chronically red-blood-cell-transfused patients. Differences in iron chelation therapy posology cause disappointing results in neurodegenerative diseases at low doses, but lifesaving outcomes in thalassemia major (TM) when using higher doses. In particular, the transformation of TM from a fatal to a chronic disease has been achieved using effective doses of oral deferiprone (L1), which improved compliance and cleared excess toxic iron from the heart associated with increased mortality in TM. Furthermore, effective L1 and L1/deferoxamine combination posology resulted in the complete elimination of EID and the maintenance of normal iron store levels in TM. The selection of effective chelation protocols has been monitored by MRI T2* diagnosis for EID levels in different organs. Millions of other iron-loaded patients with sickle cell anemia, myelodysplasia and haemopoietic stem cell transplantation, or non-iron-loaded categories with EID in different organs could also benefit from such chelation therapy advances. Drawbacks of chelation therapy include drug toxicity in some patients and also the wide use of suboptimal chelation protocols, resulting in ineffective therapies. Drug metabolic effects, and interactions with other metals, drugs and dietary molecules also affected iron chelation therapy. Drug selection and the identification of effective or optimal dose protocols are essential for positive therapeutic outcomes in the use of chelating drugs in TM and other iron-loaded and non-iron-loaded conditions, as well as general iron toxicity.


Assuntos
Sobrecarga de Ferro , Talassemia beta , Humanos , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Piridonas/efeitos adversos , Quelantes de Ferro/efeitos adversos , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/induzido quimicamente , Terapia por Quelação/métodos , Ferro/metabolismo , Talassemia beta/tratamento farmacológico , Talassemia beta/complicações , Quimioterapia Combinada
7.
Bull Cancer ; 110(11): 1176-1182, 2023 Nov.
Artigo em Francês | MEDLINE | ID: mdl-37543453

RESUMO

Iron overload (IO) is probably as toxic in elderly patients with low-risk myelodysplastic syndromes (MDS) as in young thalassemic patients. This impact is more difficult to demonstrate because of associated comorbidities. Cardiovascular disease increases vulnerability to the toxic effects of IO. In recent years, registry studies have shown a survival benefit of Iron Chelation Therapy (ICT) in these patients. These findings are now corroborated by an improvement in event-free survival in a single randomized study: the Telesto study. The EFS curves separate after two years of follow-up. This indicates inertia in the occurrence of complications. The benefits of ICT are also very slowly being revealed. It is possible to offer ICT to patients with transfusion-dependent MDS with a life expectancy of at least two years. In Telesto, patients had a serum ferritin (F) level of at least 1000ng/mL, recommendations using this F threshold as a trigger for chelation seem to be reinforced. It remains an open question whether chelation should be started earlier for effective suppression of IO-related oxidative stress. ICTs could be used in transfusion-dependent MDS patients with life expectancy greater than two years. including possibly higher risk patients responding to hypomethylating agents.


Assuntos
Sobrecarga de Ferro , Síndromes Mielodisplásicas , Humanos , Idoso , Quelantes de Ferro/uso terapêutico , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/tratamento farmacológico , Transfusão de Sangue , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Intervalo Livre de Progressão
8.
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
9.
Am J Hematol ; 98(9): 1415-1424, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37401738

RESUMO

Children with transfusion-dependent thalassemia (TDT) require regular blood transfusions that, without iron-chelation therapy, lead to iron-overload toxicities. Current practice delays chelation therapy (late-start) until reaching iron overload (serum ferritin ≥1000 µg/L) to minimize risks of iron-depletion. Deferiprone's distinct pharmacological properties, including iron-shuttling to transferrin, may reduce risks of iron depletion during mild-to-moderate iron loads and iron overload/toxicity in children with TDT. The early-start deferiprone (START) study evaluated the efficacy/safety of early-start deferiprone in infants/young children with TDT. Sixty-four infants/children recently diagnosed with beta-thalassemia and serum ferritin (SF) between 200 and 600 µg/L were randomly assigned 1:1 to receive deferiprone or placebo for 12 months or until reaching SF-threshold (≥1000 µg/L at two consecutive visits). Deferiprone was initiated at 25 mg/kg/day and increased to 50 mg/kg/day; some recipients' dosages increased to 75 mg/kg/day based on iron levels. The primary endpoint was the proportion of patients ≥SF-threshold by month 12. Monthly transferrin saturation (TSAT) assessment evaluated iron-shuttling. At baseline, there was no significant difference in mean age (deferiprone: 3.03 years, placebo: 2.63 years), SF (deferiprone: 513.8 µg/L, placebo: 451.7 µg/L), or TSAT (deferiprone: 47.98%, placebo: 43.43%) between groups. At month 12, there was no significant difference in growth or adverse event (AE) rates between groups. No deferiprone-treated patients were iron-depleted. At month 12, 66% of patients receiving deferiprone remained below SF threshold versus 39% of placebo (p = .045). Deferiprone-treated patients showed higher TSAT levels and reached ≥60% TSAT threshold faster. Early-start deferiprone was well-tolerated, not associated with iron depletion, and efficacious in reducing iron overload in infants/children with TDT. TSAT results provide the first clinical evidence of deferiprone shuttling iron to transferrin.


Assuntos
Sobrecarga de Ferro , Talassemia beta , Humanos , Criança , Lactente , Pré-Escolar , Ferro , Talassemia beta/tratamento farmacológico , Quelantes de Ferro/efeitos adversos , Transferrina , Ferritinas , Piridonas/efeitos adversos , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia
10.
Transfusion ; 63(7): 1277-1283, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37317561

RESUMO

BACKGROUND: In the Rare Blood Disorders clinic at the University of Alberta in Edmonton, red cell exchange (RCE) was utilized in transfusion-dependent thalassemia (TDT) patients with severe iron overload despite oral chelation and no access to iron infusion pumps for parenteral chelation. It was hypothesized that RCE would be less iron loading compared to simple transfusion. The purpose of this study is to document observations of the potential risks and benefits of RCE in TDT patients. STUDY DESIGN AND METHODS: TDT patients treated with RCE were identified and consented for enrolment according to local research ethics standards. Seven patients were enrolled in the study. Charts were retrospectively reviewed from the time of initiation of RCE to the time of the most recent RCE or clinic follow-up. Outcomes were documented and analyzed by descriptive analysis. RESULTS: The average age was 30 years. 85.7% were male. 100% were on oral chelation therapy and had hyperferritinemia at baseline. Outcomes included hepatic iron overload (5 of 7), cardiac dysfunction (3 of 7), worsening splenomegaly or extramedullary hematopoiesis (5 of 7), syncopal events during RCE (2 of 7), and new antibodies (1 of 7). Iron overload improved after escalated oral chelation, not in relation to RCE initiation. DISCUSSION: We hypothesize complications were higher than expected due to inadequate hematocrit increment and lack of suppression of ineffective erythropoiesis. With no observed benefit in iron status, and high complication rates, we did not find evidence to recommend RCE in patients with TDT. This case series is a hypothesis-generating study on transfusion techniques in TDT.


Assuntos
Sobrecarga de Ferro , Talassemia , Humanos , Masculino , Adulto , Feminino , Estudos Retrospectivos , Talassemia/terapia , Sobrecarga de Ferro/etiologia , Ferro , Transfusão de Sangue , Quelantes de Ferro
11.
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
12.
Transfus Clin Biol ; 30(3): 314-318, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37061177

RESUMO

BACKGROUND: anemia is the most common finding in patients with a myelodysplastic syndrome (MDS). Repetitive red blood cell (RBC) transfusions and disease-related low hepcidin levels induce secondary iron overload. Real-world data on the prevalence and treatment strategies of anemia and secondary iron overload in MDS patients, is limited. METHODS: three years of data on MDS diagnosis, anemia and ferritin management was collected in 230 MDS patients from seven non-academic hospitals in the Netherlands. Descriptive statistics and linear mixed models were used to analyze the data. RESULTS: transfusion dependent (TD) patients (n = 49) needed 1-3 RBC transfusions per month. Serum hemoglobin remained stable in both TD and transfusion-independent (TI) patients over 3 years. In the TD patients, serum ferritin increased 63 pmol/L/month. Overall, 19 (39%) were diagnosed with secondary hemochromatosis, of which 13 (68%) received chelation therapy with a heterogeneous response. CONCLUSIONS: mean hemoglobin remains stable over time in both TD and TI MDS patients. Approximately 40% of TD patients develop secondary hemochromatosis. Treatment and monitoring of secondary hemochromatosis as well as the response on chelation therapy vary substantially.


Assuntos
Anemia , Hemocromatose , Sobrecarga de Ferro , Síndromes Mielodisplásicas , Humanos , Prevalência , Sobrecarga de Ferro/epidemiologia , Sobrecarga de Ferro/etiologia , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/epidemiologia , Síndromes Mielodisplásicas/terapia , Anemia/epidemiologia , Anemia/etiologia , Anemia/terapia , Ferritinas , Hemoglobinas , Estudos de Coortes , Quelantes de Ferro
13.
Hematol Oncol Clin North Am ; 37(2): 379-391, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36907610

RESUMO

Conventional therapy for severe thalassemia includes regular red cell transfusions and iron chelation therapy to prevent and treat complications of iron overload. Iron chelation is very effective when appropriately used, but inadequate iron chelation therapy continues to contribute to preventable morbidity and mortality in transfusion-dependent thalassemia. Factors that contribute to suboptimal iron chelation include poor adherence, variable pharmacokinetics, chelator adverse effects, and difficulties with precise monitoring of response. The regular assessment of adherence, adverse effects, and iron burden with appropriate treatment adjustments is necessary to optimize patient outcomes.


Assuntos
Sobrecarga de Ferro , Talassemia , Talassemia beta , Humanos , Talassemia beta/terapia , Quelantes de Ferro/uso terapêutico , Deferiprona/uso terapêutico , Desferroxamina/uso terapêutico , Piridonas/uso terapêutico , Sobrecarga de Ferro/etiologia , Talassemia/terapia , Ferro/uso terapêutico
14.
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
15.
Curr Opin Gastroenterol ; 39(3): 146-149, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36976854

RESUMO

PURPOSE OF REVIEW: Iron overload disorders such as hemochromatosis involve unregulated absorption of dietary iron, leading to excessive iron accumulation in multiple organs. Phlebotomy is the standard of care for removal of excess iron, but dietary modification is not standardized in practice. The purpose of this article is to help standardize hemochromatosis diet counseling based on commonly asked patient questions. RECENT FINDINGS: The clinical benefit regarding dietary modification in iron overload patients is limited due to lack of large clinical trials, but preliminary results are promising. Recent studies suggest diet modification could reduce iron burden in hemochromatosis patients resulting in less annual phlebotomy as supported through small patient studies, concepts of physiology, and animal studies. SUMMARY: This article is a guide for physicians to counsel hemochromatosis patients based on commonly asked questions such as foods to avoid, foods to consume, use of alcohol, and use of supplements. The goal of this guide is to help standardize hemochromatosis diet counseling to reduce phlebotomy amount in patients. Standardization of diet counseling could help facilitate future patient studies to analyze the clinical significance.


Assuntos
Hemocromatose , Sobrecarga de Ferro , Animais , Humanos , Hemocromatose/terapia , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/terapia , Ferro , Dieta , Flebotomia/efeitos adversos
16.
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
17.
Eur J Haematol ; 110(4): 414-425, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36565288

RESUMO

OBJECTIVES: Iron overload in patients with thalassemia represents a serious complication by affecting numerous organ systems. This meta-analysis aims to establish an evidence regarding the effect of amlodipine on cardiac iron overload in thalassemia patients. METHODS: We searched PubMed, Scopus, Web of Science, Cochrane Central, and EMBASE for all relevant randomized controlled trials (RCTs). The primary outcomes were cardiac T2* and myocardial iron concentration (MIC). Secondary outcomes were liver iron concentration (LIC), risk of Gastrointestinal (G.I.) upset and risk of lower limb edema. We used Hedges' g to pool continuous outcomes, while odds ratio was used for dichotomous outcomes. RESULTS: Seven RCTs were eligible for this systematic review and meta-analysis, comprising of 233 patients included in the analysis. Amlodipine had a statistically significant lower MIC (Hedges' g = -0.82, 95% confidence interval [CI] [-1.40, -0.24], p < .001) and higher cardiac T2* (Hedges' g = 0.36, 95% CI [0.10, 0.62], p = .03). Amlodipine was comparable to standard chelation therapy in terms of the risk of lower limb edema and GI upset. CONCLUSION: Our meta-analysis found that amlodipine significantly increases cardiac T2* and decreases MIC, hence decreasing the incidence of cardiomyopathy-related iron overload in thalassemia patients.


Assuntos
Sobrecarga de Ferro , Siderose , Talassemia , Talassemia beta , Humanos , Bloqueadores dos Canais de Cálcio/uso terapêutico , Siderose/complicações , Siderose/tratamento farmacológico , Talassemia beta/complicações , Talassemia/terapia , Ferro , Sobrecarga de Ferro/etiologia , Anlodipino/uso terapêutico , Quelantes de Ferro/uso terapêutico
18.
Medicina (Kaunas) ; 58(10)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36295656

RESUMO

Non-transfusion-dependent thalassemia (NTDT) has been considered less severe than its transfusion-dependent variants. The most common forms of NTDT include ß-thalassemia intermedia, hemoglobin E/beta thalassemia, and hemoglobin H disease. Patients with NTDT develop several clinical complications, despite their regular transfusion independence. Ineffective erythropoiesis, iron overload, and hypercoagulability are pathophysiological factors that lead to morbidities in these patients. Therefore, an early and accurate diagnosis of NTDT is essential to ascertaining early interventions. Currently, several conventional management options are available, with guidelines suggested by the Thalassemia International Federation, and novel therapies are being developed in light of the advancement of the understanding of this disease. This review aimed to increase clinicians' awareness of NTDT, from its basic medical definition and genetics to its pathophysiology. Specific complications to NTDT were reviewed, along with the risk factors for its development. The indications of different therapeutic options were outlined, and recent advancements were reviewed.


Assuntos
Sobrecarga de Ferro , Talassemia , Humanos , Transfusão de Sangue , Hemoglobina E/uso terapêutico , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/tratamento farmacológico , Talassemia/complicações , Talassemia/terapia , Talassemia/diagnóstico
19.
Hemoglobin ; 46(2): 114-117, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36069257

RESUMO

Red blood cell (RBC) transfusions have been established as one of the primary therapies in treating sickle cell anemia. However, they are not free of side effects, with overloading the body with iron being one of the most important. Iron chelation therapy greatly reduces the iron load of the body. In addition, hydroxyurea (HU), an oral chemotherapeutic drug also has a significant role in the treatment of the disease with beneficial effects on many of the clinical problems that arise, mainly in reducing painful crises. The aim of this study was to investigate the effect of synergistic transfusion therapy and HU on the response to deferasirox (DFX) chelation therapy. Eighteen patients with sickle cell disease were divided into two groups based on their treatment, either with simple transfusions and DFX or with a combination of transfusion therapy, DFX and HU, and were evaluated with magnetic resonance imaging (MRI) for liver iron concentration (LIC) and biochemistry. All patients completed the study. The results of the study showed improvement in serum ferritin (FER) levels and LIC after 12 months of therapy in both groups, especially in the group receiving the combination therapy with HU. In addition, there was a noteworthy improvement in serum glutamic-oxaloacetic transaminase (SGOT), serum glutamic pyruvic transaminase (SGPT) and lactate dehydrogenase (LDH) levels with serum creatinine (Cr) levels remaining stable during the study in both groups. Hydroxyurea, when combined with iron chelators such as DFX, provides an additional benefit of iron chelation in patients receiving chronic transfusion therapy.


Assuntos
Anemia Falciforme , Quelantes de Ferro , Sobrecarga de Ferro , Alanina Transaminase/uso terapêutico , Anemia Falciforme/complicações , Anemia Falciforme/terapia , Aspartato Aminotransferases/uso terapêutico , Terapia por Quelação , Creatinina/uso terapêutico , Deferasirox/uso terapêutico , Ferritinas , Humanos , Hidroxiureia/uso terapêutico , Ferro , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Lactato Desidrogenases
20.
Int J Mol Sci ; 23(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36077584

RESUMO

Thalassemia is the most common genetic disorder worldwide. Thalassemia intermedia (TI) is non-transfusion-dependent thalassemia (NTDT), which includes ß-TI hemoglobin, E/ß-thalassemia and hemoglobin H (HbH) disease. Due to the availability of iron chelation therapy, the life expectancy of thalassemia major (TM) patients is now close to that of TI patients. Iron overload is noted in TI due to the increasing iron absorption from the intestine. Questions are raised regarding the relationship between iron chelation therapy and decreased patient morbidity/mortality, as well as the starting threshold for chelation therapy. Searching all the available articles up to 12 August 2022, iron-chelation-related TI was reviewed. In addition to splenectomized patients, osteoporosis was the most common morbidity among TI cases. Most study designs related to ferritin level and morbidities were cross-sectional and most were from the same Italian study groups. Intervention studies of iron chelation therapy included a subgroup of TI that required regular transfusion. Liver iron concentration (LIC) ≥ 5 mg/g/dw measured by MRI and ferritin level > 300 ng/mL were suggested as indicators to start iron chelation therapy, and iron chelation therapy was suggested to be stopped at a ferritin level ≤ 300 ng/mL. No studies showed improved overall survival rates by iron chelation therapy. TI morbidities and mortalities cannot be explained by iron overload alone. Hypoxemia and hemolysis may play a role. Head-to-head studies comparing different treatment methods, including hydroxyurea, fetal hemoglobin-inducing agents, hypertransfusion as well as iron chelation therapy are needed for TI, hopefully separating ß-TI and HbH disease. In addition, the target hemoglobin level should be determined for ß-TI and HbH disease.


Assuntos
Sobrecarga de Ferro , Talassemia alfa , Talassemia beta , Ferritinas , Humanos , Ferro/metabolismo , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/etiologia , Talassemia beta/genética , Talassemia beta/terapia
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