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1.
Blood ; 142(11): 949-960, 2023 09 14.
Article in English | MEDLINE | ID: mdl-37478396

ABSTRACT

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.


Subject(s)
Iron Overload , Thalassemia , beta-Thalassemia , Humans , beta-Thalassemia/therapy , beta-Thalassemia/drug therapy , Iron Chelating Agents/therapeutic use , Thalassemia/drug therapy , Iron Overload/diagnosis , Iron Overload/etiology , Iron Overload/therapy , Chelation Therapy/adverse effects
2.
J Pediatr Hematol Oncol ; 46(6): e402-e405, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38832436

ABSTRACT

BACKGROUND: Hemoglobin disorders such as thalassemia major have created an economic burden on the health care system. Iron chelation therapy (ICT) is the most expensive cost component in patients with thalassemia. ICT was administered to reduce the toxic effects of iron overload. This study aims to compare the costs of iron chelators as monotherapy in patients with thalassemia major in Indonesia, specifically in Cipto Faculty of Medicine, Universit. METHODS: This is a retrospective analytical observational study. Data were collected from the thalassemia registry from 2016 to 2019. Patients' age, gender, type of thalassemia, and type of iron chelation were recorded. Complications and total annual costs were evaluated. All thalassemia patients aged ≥2 years who were only receiving monotherapy ICT and had no history of therapy switching were eligible. We excluded subjects who moved out to other facilities or lost to follow-up. RESULTS: From a total of 256 subjects, 249 subjects were included. The median age is 28 years old. Both sexes were represented equally. As many as 96.8% of subjects have thalassemia beta. Deferiprone was the most common iron chelator used (86.7%). Complications were observed in the subjects based on 4-year data collection; most of them were cardiomyopathy, diabetes mellitus, delayed puberty, and malnutrition ( P =0.422; P =0.867; P =0.004; and P =0.125, respectively). Deferiprone had a lower mean annual cost of USD 3581 than deferasirox, which had a cost of USD 6004. CONCLUSIONS: Cardiomyopathy, diabetes mellitus, delayed puberty, and malnutrition were the most common complications found in the study. This study showed that deferiprone should be taken as consideration as a drug of choice to treat iron overload in thalassemia provided by Indonesian national health insurance which is less costly despite the probability of complications found after the treatment was given. Further investigations are required to evaluate contributing factors of complications in thalassemia.


Subject(s)
Deferasirox , Deferiprone , Iron Chelating Agents , Humans , Deferiprone/therapeutic use , Deferiprone/adverse effects , Male , Female , Deferasirox/adverse effects , Deferasirox/therapeutic use , Deferasirox/economics , Retrospective Studies , Iron Chelating Agents/economics , Iron Chelating Agents/therapeutic use , Iron Chelating Agents/adverse effects , Adult , Adolescent , Child , Thalassemia/economics , Thalassemia/drug therapy , Young Adult , Indonesia , beta-Thalassemia/drug therapy , beta-Thalassemia/economics , beta-Thalassemia/complications , Iron Overload/drug therapy , Iron Overload/economics , Iron Overload/etiology , Child, Preschool , Chelation Therapy/economics , Chelation Therapy/adverse effects
3.
Eur J Haematol ; 110(5): 490-497, 2023 May.
Article in English | MEDLINE | ID: mdl-36708354

ABSTRACT

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.


Subject(s)
Chelation Therapy , Iron Overload , Humans , Chelation Therapy/adverse effects , Iron Chelating Agents/therapeutic use , Deferasirox/therapeutic use , Deferiprone/therapeutic use , Deferoxamine/therapeutic use , Pyridones/therapeutic use , Benzoates/therapeutic use , Triazoles , Iron Overload/diagnosis , Iron Overload/drug therapy , Iron Overload/etiology , Iron
4.
Transfus Apher Sci ; 62(3): 103702, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37055329

ABSTRACT

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.


Subject(s)
Iron Overload , Nephrolithiasis , beta-Thalassemia , Humans , Child , Chelation Therapy/adverse effects , Iron Chelating Agents/adverse effects , Deferasirox/adverse effects , Deferiprone/therapeutic use , Deferoxamine/adverse effects , Benzoates/adverse effects , Triazoles , Iron Overload/drug therapy , Iron Overload/etiology , Nephrolithiasis/chemically induced , Nephrolithiasis/complications , Nephrolithiasis/drug therapy , Iron/therapeutic use , beta-Thalassemia/therapy
5.
Haematologica ; 107(2): 467-477, 2022 02 01.
Article in English | MEDLINE | ID: mdl-33406815

ABSTRACT

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.


Subject(s)
Iron Overload , Thalassemia , beta-Thalassemia , Benzoates/adverse effects , Chelation Therapy/adverse effects , Deferasirox/adverse effects , Follow-Up Studies , Humans , Iron Chelating Agents/adverse effects , Iron Overload/drug therapy , Iron Overload/epidemiology , Iron Overload/etiology , Risk Assessment , Risk Factors , Thalassemia/complications , Thalassemia/epidemiology , Thalassemia/therapy , Triazoles/adverse effects , beta-Thalassemia/complications
6.
Ann Hematol ; 101(3): 533-539, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34981144

ABSTRACT

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).


Subject(s)
Anemia, Sickle Cell/complications , Deferiprone/pharmacokinetics , Iron Chelating Agents/pharmacokinetics , Iron Overload/drug therapy , Adult , Anemia, Sickle Cell/therapy , Blood Transfusion , Chelation Therapy/adverse effects , Deferiprone/adverse effects , Deferiprone/therapeutic use , Female , Humans , Iron Chelating Agents/adverse effects , Iron Chelating Agents/therapeutic use , Iron Overload/etiology , Male , Young Adult
7.
Vox Sang ; 117(5): 733-737, 2022 May.
Article in English | MEDLINE | ID: mdl-35014065

ABSTRACT

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.


Subject(s)
Iron Overload , beta-Thalassemia , Adult , Benzoates/therapeutic use , Chelation Therapy/adverse effects , Child , Deferasirox/therapeutic use , Deferoxamine/therapeutic use , Ferritins , Humans , Iron/therapeutic use , Iron Chelating Agents/therapeutic use , Iron Overload/drug therapy , Iron Overload/etiology , Retrospective Studies , Triazoles/therapeutic use , beta-Thalassemia/complications , beta-Thalassemia/drug therapy
8.
Hemoglobin ; 46(4): 201-213, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35930250

ABSTRACT

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.


Subject(s)
Iron Overload , Thalassemia , beta-Thalassemia , Adult , Humans , beta-Thalassemia/complications , beta-Thalassemia/drug therapy , Chelation Therapy/adverse effects , Iron , Iron Chelating Agents/therapeutic use , Iron Overload/drug therapy , Iron Overload/etiology , Medication Adherence , Thalassemia/complications , Thalassemia/drug therapy
9.
Cochrane Database Syst Rev ; 6: CD013165, 2020 Jun 26.
Article in English | MEDLINE | ID: mdl-32588430

ABSTRACT

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.


Subject(s)
Chelating Agents/therapeutic use , Chelation Therapy/methods , Hyperkalemia/drug therapy , Potassium , Renal Insufficiency, Chronic/complications , Aged , Cause of Death , Chelating Agents/adverse effects , Chelation Therapy/adverse effects , Chronic Disease , Humans , Hyperkalemia/etiology , Hyperkalemia/mortality , Middle Aged , Polymers/adverse effects , Polymers/therapeutic use , Polystyrenes/adverse effects , Polystyrenes/therapeutic use , Quality of Life , Randomized Controlled Trials as Topic , Silicates/adverse effects , Silicates/therapeutic use
10.
J Pediatr Orthop ; 40(6): e473-e478, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32501918

ABSTRACT

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.


Subject(s)
Chelation Therapy/adverse effects , Deferiprone/adverse effects , Iron Chelating Agents/adverse effects , Wrist Joint/drug effects , beta-Thalassemia/drug therapy , Adolescent , Blood Transfusion , Child , Child, Preschool , Female , Forearm/diagnostic imaging , Humans , Joint Diseases/etiology , Male , Radiography , Radius/diagnostic imaging , Radius/drug effects , Ulna/diagnostic imaging , Ulna/drug effects , Wrist/diagnostic imaging , Wrist Joint/diagnostic imaging
11.
Int J Mol Sci ; 21(22)2020 Nov 20.
Article in English | MEDLINE | ID: mdl-33233561

ABSTRACT

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.


Subject(s)
Deferoxamine/administration & dosage , Iron Chelating Agents/administration & dosage , Iron Overload/drug therapy , Iron/metabolism , Transfusion Reaction/complications , beta-Thalassemia/therapy , Adult , Blood Transfusion , Cardiomyopathies/blood , Cardiomyopathies/etiology , Cardiomyopathies/physiopathology , Cardiomyopathies/prevention & control , Chelation Therapy/adverse effects , Chelation Therapy/methods , Deferoxamine/adverse effects , Drug Monitoring/instrumentation , Drug Monitoring/methods , Female , Heart/drug effects , Heart/physiopathology , Humans , Iron/toxicity , Iron Chelating Agents/adverse effects , Iron Overload/blood , Iron Overload/complications , Iron Overload/physiopathology , Liver/drug effects , Liver/metabolism , Liver/pathology , Male , Middle Aged , Pancreas/drug effects , Pancreas/metabolism , Pancreas/pathology , Transferrin/metabolism , Transfusion Reaction/blood , Transfusion Reaction/physiopathology , beta-Thalassemia/metabolism , beta-Thalassemia/pathology
12.
Ann Hematol ; 97(4): 679-684, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29318368

ABSTRACT

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.


Subject(s)
Blood Transfusion , Glycation End Products, Advanced/blood , Iron Overload/etiology , Oxidative Stress , Transfusion Reaction/physiopathology , beta-Thalassemia/blood , Adolescent , Adult , Biomarkers/blood , Chelation Therapy/adverse effects , Combined Modality Therapy/adverse effects , Cross-Sectional Studies , Deferiprone , Deferoxamine/therapeutic use , Female , Humans , Iran , Iron Overload/prevention & control , Male , Pyridones/therapeutic use , Scavenger Receptors, Class E/blood , Young Adult , beta-Thalassemia/therapy
13.
Hemoglobin ; 42(3): 213-216, 2018 May.
Article in English | MEDLINE | ID: mdl-30251901

ABSTRACT

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.


Subject(s)
Chemical and Drug Induced Liver Injury/etiology , Iron Overload/complications , beta-Thalassemia/complications , Adrenergic beta-Antagonists , Chelation Therapy/adverse effects , Chemical and Drug Induced Liver Injury/diagnosis , Critical Illness , Deferiprone , Heart Failure/complications , Heart Failure/drug therapy , Humans , Iron Overload/drug therapy , Male , Warfarin , Young Adult , beta-Thalassemia/therapy
14.
Br J Haematol ; 178(5): 676-688, 2017 09.
Article in English | MEDLINE | ID: mdl-28439891

ABSTRACT

This review outlines the effectiveness and safety of 10 different regimens for controlling iron overloading in thalassaemia major (TM). For each treatment, the strength of the evidence was documented according to the guidelines of the American College of Cardiology and the American Heart Association. Serum ferritin (SF), liver iron concentration (LIC), heart T2* signal, heart damage and survival were used to assess effectiveness. Five chelation regimens out of 10 showed Level A Evidence in controlling iron overloading, as determined by SF levels and LIC. Three out of 10 chelation regimens were able to control heart iron levels, as determined by T2* signals with Level A Evidence. Two chelation regimens were able to improve/reverse heart damage and four increased of survival with Level B Evidence. These advances mean that the current survival of TM patients is now similar to that of thalassaemia intermedia patients.


Subject(s)
Chelation Therapy/methods , Iron Chelating Agents/therapeutic use , Iron Overload/prevention & control , beta-Thalassemia/therapy , Chelation Therapy/adverse effects , Chelation Therapy/trends , Drug Therapy, Combination , Humans , Iron Chelating Agents/adverse effects , Iron Overload/etiology , Transfusion Reaction
16.
Hemoglobin ; 40(6): 435-437, 2016 Nov.
Article in English | MEDLINE | ID: mdl-28361596

ABSTRACT

A 29-year-old male with transfusion-dependent ß-thalassemia major (ß-TM), splenectomized and on chelation therapy with deferiprone (DFP or L1) due to heart and liver hemosiderosis, presented with high fever and agranulocytosis. Deferiprone was discontinued and a broad spectrum antibiotic therapy was started intravenously. The patient remained febrile and showed no recovery of neutrophil count even after the initiation of granulocyte colony-stimulation factor (G-CSF). After 12 days at the hospital, he developed respiratory failure and was transferred to the intensive care unit (ICU) where he developed multi-organ failure and died 3 days later. To investigate the mechanism of agranulocytosis, bone marrow mononuclear cells of a healthy volunteer were plated on culture dishes, with or without the patient's serum. The observation of colony forming units of progenitor cells in dishes that contained the patient's serum, provided inconclusive explanation of the possible mechanism of DFP-induced agranulocytosis. This is a case of fatal agranulocytosis developing in a patient being treated with DFP, a well recognized but rare complication of this drug. Further studies are required in order to elucidate the possible pathogenic mechanism of agranulocytosis due to DFP and to provide clear guidelines in order to best care for the patient.


Subject(s)
Agranulocytosis/chemically induced , Pyridones/adverse effects , beta-Thalassemia/complications , Adult , Agranulocytosis/diagnosis , Agranulocytosis/pathology , Bone Marrow Cells/pathology , Bone Marrow Examination , Chelation Therapy/adverse effects , Deferiprone , Fatal Outcome , Humans , Leukocytes, Mononuclear/pathology , Male , Pyridones/therapeutic use , Stem Cells/pathology , beta-Thalassemia/drug therapy
17.
Br J Haematol ; 168(6): 882-90, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25402221

ABSTRACT

Some patients with ß thalassaemia experience non-progressive creatinine increases with deferasirox, mostly within normal limits; the mechanisms involved are not fully elucidated. The effects of deferasirox on renal haemodynamics, including glomerular filtration rate (GFR) and renal plasma flow (RPF), were investigated in a Phase I, open-label study in ß thalassaemia major patients with iron overload. Patients received deferasirox 30 mg/kg/d up to Week 8, followed by a 2-week washout period, and extended treatment up to Week 104 with a 4-week washout period. In the short-term study (n = 11), mean GFR and RPF declined from baseline to Week 8 (mean [%] change:-9·2 [-9·5%] and -105·7 ml/min [-17·8%], respectively). A similar pattern was observed during the long-term study (n = 5); mean GFR and RPF decreased up to Week 52 (-19·1 [-17·7%] and -155·6 ml/min [-26·1%]), with similar change at Week 104 (-18·4 [-17·2%] and -115·9 ml/min [-19·6%]). Measures returned to baseline values after each washout. Serum creatinine and creatinine clearance followed a similar pattern. Effects of deferasirox on renal haemodynamics were mild and reversible for up to 2 years of treatment, with no progressive worsening of renal function over time. www.clinicaltrials.gov: NCT00560820.


Subject(s)
Benzoates/pharmacology , Iron Chelating Agents/pharmacology , Renal Circulation/drug effects , Transfusion Reaction , Triazoles/pharmacology , beta-Thalassemia/physiopathology , Adult , Benzoates/adverse effects , Benzoates/therapeutic use , Biomarkers/blood , Biomarkers/urine , Chelation Therapy/adverse effects , Chelation Therapy/methods , Creatinine/blood , Deferasirox , Female , Ferritins/blood , Glomerular Filtration Rate/drug effects , Hemodynamics/drug effects , Humans , Iron Chelating Agents/adverse effects , Iron Chelating Agents/therapeutic use , Iron Overload/drug therapy , Iron Overload/etiology , Male , Middle Aged , Triazoles/adverse effects , Triazoles/therapeutic use , Young Adult , beta-Thalassemia/blood , beta-Thalassemia/therapy
18.
Pediatr Blood Cancer ; 62(9): 1592-6, 2015 Sep.
Article in English | MEDLINE | ID: mdl-25820920

ABSTRACT

BACKGROUND: The high cost, coupled with the need for continuous infusion, renders Desferrioxamine (DFO), a non-feasible option for iron-chelation in a large majority of patients with ß-thalassemia major in developing countries. Monotherapy with deferiprone (DFP) or deferasirox (DFX) may not always attain optimal control, particularly in heavily iron-loaded patients. Combination of DFP and DFX is a potential alternative. PROCEDURE: A prospective, single-center, open-label, uncontrolled study was conducted to evaluate the safety and efficacy of the combination in patients with ß-thalassemia major. Patients who had received either DFP or DFX for >1 year and a serum ferritin >2,000 µg/L were enrolled. Blood counts, liver/renal functions, and serum ferritin were monitored during the 1-year study period. Facilities for cardiac T2*-MRI were unavailable. RESULTS: Thirty-six patients with a mean age of 13 ± 6.9 years (range: 4-29) and a ferritin of 6,768 ± 4,145 µg/L formed the study cohort. Eight (22%) patients had transient gastrointestinal adverse effects. DFX was discontinued in one patient for persistent abdominal pain/diarrhea. Eight (22%) had joint symptoms; DFP was discontinued in two. Four (11%) patients had elevation in AST/ALT levels, managed with temporary interruption of DFX. Nine (25%) had an inconsistent elevation of creatinine to >33% of baseline; no intervention was done. One had transient proteinuria. None had neutropenia. At the end of 1 year, the serum ferritin reduced by a mean value of 3,275.3 ± 618.2 µg/L (P < 0.001). CONCLUSIONS: The oral combination was found to be safe, efficacious, and a feasible option in patients with suboptimal response to monotherapy.


Subject(s)
Benzoates/therapeutic use , Chelation Therapy , Iron Chelating Agents/therapeutic use , Iron Overload/drug therapy , Iron/blood , Pyridones/therapeutic use , Triazoles/therapeutic use , beta-Thalassemia/complications , Adolescent , Adult , Benzoates/administration & dosage , Benzoates/adverse effects , Chelation Therapy/adverse effects , Chemical and Drug Induced Liver Injury/etiology , Child , Child, Preschool , Deferasirox , Deferiprone , Drug Eruptions/etiology , Drug Therapy, Combination , Female , Ferritins/blood , Gastrointestinal Diseases/chemically induced , Humans , Iron Chelating Agents/adverse effects , Iron Overload/etiology , Joint Diseases/chemically induced , Male , Prospective Studies , Proteinuria/chemically induced , Pyridones/administration & dosage , Pyridones/adverse effects , Transfusion Reaction , Treatment Outcome , Triazoles/administration & dosage , Triazoles/adverse effects , Young Adult , beta-Thalassemia/blood , beta-Thalassemia/therapy
19.
Cochrane Database Syst Rev ; (5): CD010766, 2015 May 11.
Article in English | MEDLINE | ID: mdl-26106752

ABSTRACT

BACKGROUND: It has been suggested that the severity of autism spectrum disorder (ASD) symptoms is positively correlated with the level of circulating or stored toxic metals, and that excretion of these heavy metals, brought about by the use of pharmaceutical chelating agents, results in improved symptoms. OBJECTIVES: To assess the potential benefits and adverse effects of pharmaceutical chelating agents (referred to as chelation therapy throughout this review) for autism spectrum disorder (ASD) symptoms. SEARCH METHODS: We searched the following databases on 6 November 2014: CENTRAL, Ovid MEDLINE, Ovid MEDLINE In-Process, Embase,PsycINFO, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and 15 other databases, including three trials registers. In addition we checked references lists and contacted experts. SELECTION CRITERIA: All randomised controlled trials of pharmaceutical chelating agents compared with placebo in individuals with ASD. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, assessed them for risk of bias and extracted relevant data. We did not conduct a meta-analysis, as only one study was included. MAIN RESULTS: We excluded nine studies because they were non-randomised trials or were withdrawn before enrolment.We included one study, which was conducted in two phases. During the first phase of the study, 77 children with ASD were randomly assigned to receive seven days of glutathione lotion or placebo lotion, followed by three days of oral dimercaptosuccinic acid (DMSA). Forty-nine children who were found to be high excreters of heavy metals during phase one continued on to phase two to receive three days of oral DMSA or placebo followed by 11 days off, with the cycle repeated up to six times. The second phase thus assessed the effectiveness of multiple doses of oral DMSA compared with placebo in children who were high excreters of heavy metals and who received a three-day course of oral DMSA. Overall, no evidence suggests that multiple rounds of oral DMSA had an effect on ASD symptoms. AUTHORS' CONCLUSIONS: This review included data from only one study, which had methodological limitations. As such, no clinical trial evidence was found to suggest that pharmaceutical chelation is an effective intervention for ASD. Given prior reports of serious adverse events, such as hypocalcaemia, renal impairment and reported death, the risks of using chelation for ASD currently outweigh proven benefits. Before further trials are conducted, evidence that supports a causal link between heavy metals and autism and methods that ensure the safety of participants are needed.


Subject(s)
Chelating Agents/administration & dosage , Chelation Therapy , Child Development Disorders, Pervasive/therapy , Administration, Oral , Chelating Agents/adverse effects , Chelation Therapy/adverse effects , Child , Child Development Disorders, Pervasive/blood , Child, Preschool , Female , Glutathione/administration & dosage , Humans , Male , Metals, Heavy/blood , Randomized Controlled Trials as Topic , Skin Cream/administration & dosage , Succimer/administration & dosage , Succimer/adverse effects
20.
Hemoglobin ; 39(1): 69-73, 2015.
Article in English | MEDLINE | ID: mdl-25572183

ABSTRACT

Iron overload is a common finding in chronically transfused ß-thalassemia major (ß-TM) patients with possible effect on ß cell function and insulin resistance. In this study we aimed to evaluate glucose metabolism, insulin resistance and ß cell function in ß-TM patients. A total of 78 transfusion-dependent ß-TM patients and 40 age and sex matched normal children were included. Oral glucose tolerance tests (OGTT) were performed in all subjects. Fasting plasma insulin level, insulin resistance index (IRI) and ß cell function index (BFI) were also estimated. ß-Thalassemia major patients had significantly more abnormal OGTT than the control group. ß-Thalassemia major patients had significantly higher levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) fasting blood sugar and IRI than the control group. Findings between ß-thalassemia (ß-thal) patients, with and without abnormal OGTT results, were also compared; ß-thal patients with abnormal OGTT had significantly higher duration of chelation therapy, serum ferritin levels, AST, ALT and increased IRI and decreased BFI in comparison to patients with normal OGTT. Abnormal glucose metabolism is common in ß-TM patients with chelation therapy and multiple transfusions which are attributable to impaired ß cells' function and increased insulin resistance.


Subject(s)
Insulin Resistance , Insulin-Secreting Cells/pathology , beta-Thalassemia/complications , Adolescent , Blood Glucose/analysis , Blood Glucose/metabolism , Case-Control Studies , Chelation Therapy/adverse effects , Child , Female , Glucose Tolerance Test , Humans , Insulin/blood , Insulin/metabolism , Male , Transfusion Reaction , Young Adult , beta-Thalassemia/blood , beta-Thalassemia/metabolism , beta-Thalassemia/therapy
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