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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This study examined the relationship between hepatic and myocardial iron concentration, assessed by T2*-MRI in 66 patients (3-82 years) with transfusion-dependent anemias and thalassemia intermedia, to determine whether hepatic iron levels alone suffice for chelation adjustments. We found a poor correlation between hepatic and myocardial iron (r = 0.10, P = 0.43) and identified a subgroup (14%) with increased myocardial iron without a matched degree of hepatic hemosiderosis. Left ventricular ejection fraction was insensitive for detecting elevated myocardial iron. These findings were present in both adult and pediatric patients. We recommend therapeutic monitoring of iron burden by evaluation of both liver and myocardial iron with T2*-MRI.
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PMID:Practical implications of liver and heart iron load assessment by T2*-MRI in children and adults with transfusion-dependent anemias. 1866 91

Beta-thalassaemia is the most common hemoglobinopathies in our region with treatment of regular blood transfusion. Iron overload and hemosiderosis can cause organ involvement. Recent studies have focused on pulmonary involvement and pathophysiology of lung damage. The goal of this study was to investigate the pulmonary abnormalities in thalassemic patients in relation with sign and symptoms and iron overload. The authors studied pulmonary function test (PFT) at the Adult Thalassemia Clinic in Tehran. The history of blood transfusion, iron chelation, respiratory problems, and drug usage was taken. Physical examination, PFT, arterial blood gas (ABG), and chest X-ray (CXR) were done. In total, 139 patients were studied. The mean age was 21.1 years and mean duration of transfusion was 18 years. It was found that 133 patients (95.7%) did not have respiratory problems and only 6 (4.3%) had some respiratory complaints. In CXR, 100 patients (89.3%) had normal lung pattern and others (10.7%) had variable degrees of abnormal lung pattern. In ABG, mean of Po(2) was 73.5% and mean of O(2) saturation was 90.6%. In PFT, 101 patients (72.7%) had restrictive pattern, 35 (25.1%) had normal pattern, and 3 (2.2%) had combined pattern. According to vital capacity, the patients were placed in five categories: 54 patients (38.8%) normal, 37 (26.6%) mild, 35 (25.3%) moderate, 10 (7.2%) severe, and 3 (2.1%) extremely severe pulmonary deficit. There was no statistical significance between PFT results with all variables studied, except duration of blood transfusion, which may be considered a indirect effect of iron load (p = .05, r = .361). According to these results, restrictive pattern was the most common finding (72.7%) in PFT, while 95.7% of patients had no respiratory complaint, and in the chest X-ray group, 89.3% had normal pattern. The authors conclude that the lung may be considered a site for organ damage, and alteration of pulmonary function may be expected in transfusion-dependent patients in spite of no pulmonary symptoms or normal CXR. In recent years, because of new iron chelating drugs, doctors can expect thalassemic patients to have a long life-time and need to increase their quality of life. One way to do this is to evaluate the respiratory system by PFT to prevent the squeal of pulmonary disease.
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PMID:Pulmonary function test in transfusion-dependent beta-thalassemia patients. 1872 79

We performed MRI assessment in 37 adult Chinese patients with thalassemia intermedia and hemoglobin H disease. Despite abnormal ferritin and liver T2*, only 5% of patients had cardiac hemosiderosis. The two patients with reduced ejection fraction had normal cardiac T2*. Half of the cases showed pituitary and pancreatic iron loading. Subclinical endocrine abnormalities (HOMA, insulin growth factor) showed correlation with pancreatic, pituitary, and cardiac MRI values. Prospective data with serial functional and imaging monitoring is needed to verify the utility for chelation to improve cardiac and endocrine function in this group of patients.
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PMID:Organ-specific hemosiderosis and functional correlation in Chinese patients with thalassemia intermedia and hemoglobin H disease. 1916 82

Tens of thousands of transfusion-dependent (eg, thalassemia) patients worldwide suffer from chronic iron overload and its potentially fatal complications. The oral iron chelator deferasirox has become commercially available in many countries since 2006. Although this alternative to parenteral deferoxamine has been a major advance for patients with transfusional hemosiderosis, a proportion of patients have suboptimal response to the maximum approved doses (30 mg/kg per day), and do not achieve negative iron balance. We performed a prospective study of oral deferasirox pharmacokinetics (PK), comparing 10 transfused patients with inadequate deferasirox response (rising ferritin trend or rising liver iron on deferasirox doses > 30 mg/kg per day) with control transfusion-dependent patients (n = 5) with adequate response. Subjects were admitted for 4 assessments: deferoxamine infusion and urinary iron measurement to assess readily chelatable iron; quantitative hepatobiliary scintigraphy to assess hepatic uptake and excretion of chelate; a 24-hour deferasirox PK study following a single 35-mg/kg dose of oral deferasirox; and pharmacogenomic analysis. Patients with inadequate response to deferasirox had significantly lower systemic drug exposure compared with control patients (P < .00001). Cmax, volume of distribution/bioavailability (Vd/F), and elimination half-life (t(1/2)) were not different between the groups, suggesting bioavailability as the likely discriminant. Effective dosing regimens for inadequately responding patients to deferasirox must be determined. This trial has been registered at http://www.clinicaltrials.gov under identifier NCT00749515.
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PMID:Deferasirox pharmacokinetics in patients with adequate versus inadequate response. 1972 55

The problem of spinal cord compression (SCC) related to extramedullary hematopoiesis (EMH) in beta-thalassemia (beta-thal) patients, both clinically and radiologically and its correlation with laboratory parameters of anemia and hemosiderosis was assessed. Sixty beta-thal patients were included and divided into group I: 40 beta-thal major patients (beta-TM), aged 7-30 years with a mean age of 15 +/- 5.3 years, group II: 20 beta-thal intermedia patients (beta-TI) aged 6-20 years with a mean age of 13 +/- 4.6 years. They were subjected to neurological examination, thoracic and lumbosacral computed tomography (CT) and magnetic resonance imaging (MRI). Spinal EMH was found in 13.3% of the thalassemic patients with a higher incidence in beta-TI compared to beta-TM patients (p = 0.03). Evidence of spinal EMH was associated with higher serum ferritin (p < 0.0001), lower pre transfusion hemoglobin (Hb) (p = 0.002) and lower transfusion index (p = 0.01). Extramedullary hematopoiesis was more evident in young beta-TI patients, and was related to inadequate chelation, high serum ferritin and inadequate transfusion therapy.
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PMID:Spinal cord compression and extramedullary hematopoiesis in young Egyptian beta-thalassemia patients. 1995 90

Diabetes Mellitus is a major endocrinopathy, which occurs due transfusional haemosiderosis and is found in 20-30% of adult patients with beta-thalassaemia worldwide, accounting for significant morbidity. It is multifactorial with iron loading being the dominant cause and its management poses a clinical challenge. Diabetes in thalassaemia patients is distinct from type 2 diabetes. It is peculiar in many aspects including its pathophysiology and occurs due to insulin resistance as well as islet cell insufficiency. This article reviews the natural history of diabetes in this presentation with emphasis on prevention monitoring and management. Use of MRI techniques may be useful for future monitoring as well as biochemical monitoring to prevent complications of diabetes. Early intervention with intensified chelation may reverse pancreatic function and structural changes as evident from MRI.
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PMID:New concept in natural history and management of diabetes mellitus in thalassemia major. 2000 15

Iron overload is a serious and potentially fatal condition that results from multiple blood transfusions required over a long period of time to treat certain types of anemias such as, that caused by beta-thalassemia, sickle cell disease and myelodysplastic syndrome. Deferoxamine, which has been used since four decades as an iron chelator has limited efficacy due to its demanding therapeutic regimen, leading to poor compliance. Deferasirox, once daily oral iron chelator provides an effective alternative to Deferoxamine in the treatment of transfusional hemosiderosis. In this review, the role of Deferasirox as an ideal iron chelator has been discussed. Pubmed searches on Deferasirox were carried out for the same. Several studies demonstrated the safety and efficacy of Deferasirox in reducing iron burden in iron-overloaded patients with beta-thalassemia, sickle cell anemia and myelodysplastic anemia. Thus, convenient, effective and tolerable chelation therapy with oral Deferasirox is likely to be a significant development in the treatment of transfusional iron overload, due to its ability to provide constant chelation coverage and the potential to improve compliance.
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PMID:Deferasirox: oral, once daily iron chelator--an expert opinion. 2017 10

Deferasirox is a new oral iron chelator. It is the first oral iron chelator approved in USA by FDA for transfusion-dependent patients above 2 years suffering from severe chronic iron overload. It is also recommended as the initial therapy for patients over the age of 6 years who are suffering from beta-thalassaemia. The clinical study is developing in China. This review focuses the related studies and the latest progression about deferasirox. The phase II and III clinical trials and pharmacokinetics indicated that deferasirox is a safety and effective oral iron chelator, can significantly decrease the myocardial and hepatic iron load, also is easy to accept for patients. The common adverse reactions are gastrointestinal symptom and rash. But it was recently reported that deferasirox has some rare adverse events to which we must attach importance, especially for the special people. Besides the patients with chronic iron overload resulting from blood transfusions (transfusional hemosiderosis), the drug is also used for the patients who has accepted auto-SCT or suffered from reversible renal inadequacy caused by Fanconi syndrome. The standard dosage is not useful to every patient. The clinician should adjust dosage based on the patient's condition and related indexes. The serum ferritin is not one and reliable index to monitoring the effect and adjust the dosage. Otherwise, this review recommends some new characters of deferasirox, e.g. anti-fungus, anti-cell proliferation and so on.
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PMID:[Deferasirox--a new oral iron chelator--review]. 2112 94

Over the past four decades, there have been dramatic improvements in survival for patients with thalassemia major due in large measure to improved iron chelators. Two chelators are approved for use in the United States and Canada, parenteral deferoxamine and oral deferasirox. Three are available in much of the rest of the world, where oral deferiprone is also approved (in the United States, deferiprone is only available in studies, for emergency use, or on a "compassionate-use" basis). Many trials and worldwide clinical experience demonstrate that each of the three drugs can chelate and remove iron, and thereby prevent or improve transfusional hemosiderosis in thalassemia patients. However, the chelators differ strikingly in side-effect profile, cost, tolerability and ease of adherence, and (to some degree) efficacy for any specific patient. The entire field of chelator clinical trials suffers from the fact that each drug (as monotherapy or in combination) has not been tested directly against all of the other possibilities. Acknowledging the challenges of assessing chelators with diverse properties and imperfect comparative data, the purpose of this review is to summarize the last 4 years of studies that have improved our understanding of the applications and limitations of iron chelators in various settings for thalassemia patients, and to point out areas for much-needed future research.
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PMID:Update on iron chelators in thalassemia. 2123 34

Transfusional hemosiderosis is a frequent complication in patients with transfusion dependent chronic diseases such as thalassemias and severe type of sickle cell diseases. As there are no physiological mechanisms to excrete the iron contained in transfused red cells (1 unit of blood contains approximately 200 mg of iron) the excess of iron is stored in various organs. Cardiomyopathy is the most severe complication covering more than 70% of the causes of death of thalassemic patients. Although the current reference standard iron chelator deferoxamine (DFO) has been used clinically for over four decades, its effectiveness is limited by a demanding therapeutic regimen that leads to poor compliance. Despite poor compliance, because of the inconvenience of subcutaneous infusion, DFO improved considerably the survival and quality of life of patients with thalassemia. Deferiprone since 1998 and Deferasirox since 2005 were licensed for clinical use. The oral chelators have a better compliance because of oral use, a comparable efficacy to DFO in iron excretion and probably a better penetration to myocardial cells. Considerable increase in iron excretion was documented with combination therapy of DFO and Deferiprone. The proper use of the three chelators will improve the prevention and treatment of iron overload, it will reduce complications, and improve survival and quality of life of transfused patients.
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PMID:Iron chelation therapy in thalassemia syndromes. 2141 99


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