Use of rapid cardiac magnetic resonance imaging to guide chelation therapy in patients with transfusion-dependent thalassaemia in India: UMIMI study.

AIMS: To explore the impact of incorporating a faster cardiac magnetic resonance (CMR) imaging protocol in a low-middle-income country (LMIC) and using the result to guide chelation in transfusion-dependent patients. METHODS AND RESULTS: A prospective UK-India collaborative cohort study was conducted in two cities in India. Two visits 13 months apart included clinical assessment and chelation therapy recommendations based on rapid CMR results. Participants were recruited by the local patient advocate charity, who organized the patient medical camps. The average scanning time was 11.3 ± 2.5 min at the baseline and 9.8 ± 2.4 min (P < 0.001) at follow-up. The baseline visit was attended by 103 patients (mean age 25 years) and 83% attended the second assessment. At baseline, 29% had a cardiac T2* < 20 ms, which represents significant iron loading, and 12% had left ventricular ejection fraction <60%, the accepted lower limit in this population. Only 3% were free of liver iron (T2* ≥ 17 ms). At 13 months, more patients were taking intensified dual chelation therapy (43% vs. 55%, P = 0.002). In those with cardiac siderosis (baseline T2* < 20 ms), there was an improvement in T2*-10.9 ± 5.9 to 13.5 ± 8.7 ms, P = 0.005-and fewer were classified as having clinically important cardiac iron loading (T2* < 20 ms, 24% vs. 16%, P < 0.001). This is the first illustration in an LMIC that incorporating CMR results into patient management plans can improve cardiac iron loading. CONCLUSION: For thalassaemia patients in an LMIC, a simplified CMR protocol linked to therapeutic recommendation via the patient camp model led to enhanced chelation therapy and a reduction in cardiac iron in 1 year.

Interrelationship between liver T2*-weighted magnetic resonance imaging and acoustic radiation force impulse elastography measurement results and plasma ferritin levels in children with ß-thalassemia major.

PURPOSE: To evaluate correlation and agreement between T2*-weighted magnetic resonance imaging (T2*-wMRI), acoustic radiation force impulse elastography (ARFI-e) measurement results of liver and plasma ferritin levels (PFLs) in children with ß-thalassemia major (ß-TM). METHODS: The study included 40 pediatric patients (aged 64-216 months; 14 girls, 26 boys) receiving blood transfusion and chelation therapy. To detect the severity of liver iron overload (LIO) and concomitant parenchymal fibrosis, T2*-wMRI and ARFI-e measurements were performed from the right lobe segments. Student's t-test, Mann-Whitney U, ANOVA, Spearman's test and ICC were used for statistical analysis. RESULTS: After the measurements of T2*-wMRI, patients were grouped as normal in 4 (10%), mild in 11 (27.5%), moderate in 21 (52.5%), and severe in 4 (10%) cases in terms of LIO. Combined moderate and severe groups had significantly higher ARFI-e and PFL values than the combination of other groups (p = .001, p = .040). The ARFI-e measurements of boys were found to be significantly higher than those of girls (p = .023). A strong negative correlation between T2*-wMRI and ARFI-e and a moderate negative correlation between T2*-wMRI and PFL were detected (p;r = 0.001;-0.606, p;r = 0.009; -0.407). A strong positive correlation was found between ARFI-e values and PFL (p;r = 0.001; 0.659). The optimal cut-off value of ARFI-e to predict liver fibrosis because of moderate&severe LIO was determined to be 1.29 M/s (80% sensitivity and 88% specificity). A moderate agreement was observed between the T2*-wMRI and ARFI-e methods [ICC: 0.680, 95% CI: (0.470 to 0.817)]. CONCLUSION: Given the strong correlation and moderate agreement between ARFI-e and T2*-wMRI, ARFI -e could be used to monitor LIO in children with ß-TM.

2021 update on clinical trials in ß-thalassemia.

The treatment landscape for patients with ß-thalassemia is witnessing a swift evolution, yet several unmet needs continue to persist. Patients with transfusion-dependent ß-thalassemia (TDT) primarily rely on regular transfusion and iron chelation therapy, which can be associated with considerable treatment burden and cost. Patients with non-transfusion-dependent ß-thalassemia (NTDT) are also at risk of significant morbidity due to the underlying anemia and iron overload, but treatment options in this patient subgroup are limited. In this review, we provide updates on clinical trials of novel therapies targeting the underlying pathology in ß-thalassemia, including the α/non-α-globin chain imbalance, ineffective erythropoiesis, and iron dysregulation.

COVID-19 Pandemic and Thalassemia Major Patients: Transfusion Practice and Treatment Assessment.

BACKGROUND: When the COVID-19 epidemic occurred for the first time in December 2019, the governments worldwide took some restriction measures for slowing the spread of novel coronavirus. Eventually, there was a considerable decrease in volunteer blood donations. Regular transfusions and follow-up of patients with thalassemia major (TM) should be maintained during this period. It is possible that the treatment of the patients with TM may hinder due to the difficulty of reaching the treatment center and the difficulty of blood supply. Thus, in this study, we aimed to investigate whether there were any differences in the follow-up and treatment of the patients with TM during the outbreak. MATERIALS AND METHODS: Sixty-one patients with TM who were followed up in our center without COVID-19 contact history and symptoms were included in this study. The demographic features and red blood cell volume per kilogram they received, pretransfusion hemoglobin, serum ferritin (SF) level, biochemical parameters, and transfusion interval were recorded. The difference between the arithmetic mean of the data before and during the pandemic was evaluated. RESULTS: In this study, 61 patients with TM (32 males/29 females, mean age 13.9±6.8 y) were evaluated. The mean pretransfusion hemoglobin value was 9.14±0.77 g/dL and 8.87± 0.80 g/dL before and during the pandemic, respectively (P=0.023). There was no difference between before and during the pandemic concerning transfusion interval and transfusion volume. However, SF levels increased above 1000 ng/mL in 16.6% of patients. CONCLUSION: Although blood donation decreased significantly during the pandemic, it was observed in this study that the blood needs of patients with TM could be provided. The results of the SF level showed that the management of chelation therapy should be more meticulous. However, we should be ready for the challenges in the transfusion practice of patients with TM due to fluctuations in the COVID-19 pandemic.

Management of Iron Overload in Beta-Thalassemia Patients: Clinical Practice Update Based on Case Series.

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.

Challenges of blood transfusions in ß-thalassemia.

Patients with ß-thalassemia major (BTM) require regular blood transfusions, supported by appropriate iron chelation therapy (ICT), throughout their life. ß-thalassemia is a global disease that is most highly prevalent in Southeast Asia, Africa, and Mediterranean countries. However, the global distribution of patients with ß-thalassemia is changing due to population migration, and Northern European countries now have significant thalassemia populations. Globally, many patients with BTM have limited access to regular and safe blood transfusions. A lack of voluntary nonremunerated blood donors, poor awareness of thalassemia, a lack of national blood policies, and fragmented blood services contribute to a significant gap between the timely supply of, and demand for, safe blood. In many centers, there is inadequate provision of antigen testing, even for common red cell antigens such as CcEe and Kell. Policies to raise awareness and increase the use of red blood cell antigen testing and requesting of compatible blood in transfusion centers are needed to reduce alloimmunization (the development of antibodies to red blood cell antigens), which limits the effectiveness of transfusions and the potential availability of blood. Patients with BTM are also at risk of transfusion-transmitted infections unless appropriate blood screening and safety practices are in place. Hence, many patients are not transfused or are undertransfused, resulting in decreased health and quality-of-life outcomes. Hemovigilance, leukoreduction, and the ability to thoroughly investigate transfusion reactions are often lacking, especially in resource-poor countries. ICT is essential to prevent cardiac failure and other complications due to iron accumulation. Despite the availability of potentially inexpensive oral ICT, a high proportion of patients suffer complications of iron overload and die each year due to a lack of, or inadequate, ICT. Increased awareness, training, and resources are required to improve and standardize adequate blood transfusion services and ICT among the worldwide population of patients with BTM. ICT needs to be available, affordable, and correctly prescribed. Effective, safe, and affordable new treatments that reduce the blood transfusion burden in patients with ß-thalassemia remain an unmet need.

Colla corii asini might upregulate ZNF471 and THOC5 by KRAB domain-containing zinc-finger protein pathway and THO complex subunit 5 pathway to improve anemia of pregnant women with ß-thalassemia.

Pregnant patients with ß-thalassemia are more likely to have progressive anemia which expose them to risk of adverse pregnancy outcomes, blood transfusion, and iron overload. Results from our previous study indicated that Colla corii asini (CCA, E'jiao), a natural ingredient of traditional Chinese medicine, could significantly increase hemoglobin level of pregnant women with ß- thalassemia, but the underlying molecular mechanism was unclear. Thus, we applied high-throughput transcriptome sequencing to study the transcriptomic change before and after the CCA treatment. Twenty eligible pregnant women were recruited and randomized to either the CCA treatment group or the blank control group in a 3:1 ratio. Patients in the treatment group orally received daily 15 g CCA powder for 4 weeks. We analyzed the therapeutic effect indexes and the transcriptomic change in subjects' peripheral blood before and after treatment. We found that ß CD 41-42(-TTCT)/ßA was the main genotype of the subjects. The regulatory impact of CCA treatment became more evident among the subjects of genotype ß CD 41-42(-TTCT)/ßA. Gene ontogenesis analysis revealed that the top five molecular functions of differentially expressed genes were involved in membrane functionality and cellular structure. We further identified two consistent upregulated genes ZNF471 and THOC5 in the effective treatment group, which were engaged in Kruppel-associated box (KRAB) domain-containing zinc-finger protein pathway and THOC5 pathway, respectively. Based on our current findings, we hypothesize that the anti-anemia effect of CCA on pregnant women with ß-thalassemia might be related to translation regulation of spectrin synthesis, membrane stability, and eventually prolonged the life span of erythrocytes.

Elevated Prevalence of Abnormal Glucose Metabolism and Other Endocrine Disorders in Patients with ß-Thalassemia Major: A Meta-Analysis.

BACKGROUND: Endocrinopathies are common in patients with ß-thalassemia major despite parenteral iron chelation therapy with deferoxamine. Prevalence of abnormal glucose metabolism in previous studies was controversial. The aim of this study was to discuss the prevalence of abnormal glucose metabolism in ß-thalassemia major based on a meta-analysis. METHODS: PubMed, ScienceDirect, Springerlink, Ovid, Web of Science, MEDLINE, Wanfang database, and Chinese National Knowledge Internet were searched for relevant articles. Two authors selected the articles according to the inclusion criteria and then extracted the data. The prevalence of diabetes mellitus (DM) in ß-thalassemia major was defined as the primary outcome. The prevalence with the 95% confidence interval (95%CI) was used to evaluate the proportion of abnormal glucose metabolism and other endocrine disorders in patients with ß-thalassemia major. Subgroup analyses were applied to explore the prevalence in different regions. Sensitivity analysis and publication bias assessment were also conducted. RESULTS: A total of 44 studies with 16605 cases were included in this analysis. Diabetes mellitus was present in 6.54% (95% CI: 5.30%-7.78%). The fixed subgroup study revealed that the region with the highest prevalence was the Middle East (prevalence= 7.90%, 95% CI: 5.75%-10.05%). The accumulated meta-analysis revealed that the prevalence of DM in ß-thalassemia major was relatively steady in each year. The prevalence of impaired fasting glucose (IFG), impaired glucose tolerance (IGT), and other endocrine disorders in ß-thalassemia major was 17.21% (95% CI: 8.43%-26.00%), 12.46% (95% CI: 5.98%-18.94%), and 43.92% (95% CI: 37.94%-49.89%), respectively. Sensitivity analysis showed that the pooled results were robust; publication bias assessment revealed that there was no significant evidence that the pooled results were influenced by publication bias. CONCLUSION: High prevalence of endocrine disorders involving abnormal glucose metabolism was detected in ß-thalassemia major. Treatment and prevention measurements may be necessary to prevent growth and endocrine problems.

Major Issues of Care in Thalassemia Major Children Refugees.

Beta thalassemia major (ßTM) is the most common inherited hemoglobinopathy. Management essentially focuses on preventing and treating complications. Conventional treatment is based on a regular blood transfusion program, and chelation therapy. Management essentially focuses on preventing and treating complications. Severe complications of ßTM are very rarely seen in children in Europe. In the context of the migrant crisis, pediatricians will be confronted with the challenge of managing severe complicated ßTM. We report the case of 2 Syrian 10-year-old twin girls who arrived to France with numerous and severe complications of ßTM: hemochromatosis, alloimmunization, hypopituitarism, osteopenia… Their clinical management, which led to successful vital and functional improvement, is reported in this article.

Green tea extract modulates oxidative tissue injury in beta-thalassemic mice by chelation of redox iron and inhibition of lipid peroxidation.

Iron overload in patients with ß-thalassemia can cause oxidative organ dysfunction. Iron chelation along with antioxidant supplementation can ameliorate such complications and prolong lives. Green tea extract (GTE) rich in epigallocatechin-3-gallate (EGCG) exhibits anti-oxidation and iron chelation properties in ß-knockout thalassemic (BKO) mice diagnosed with iron overload. We investigated the effects of GTE and deferiprone (DFP) alone in combination with one another, and upon the levels of redox-active iron, lipid-peroxidation product, insulin and hepcidin in BKO mice. A state of iron overload was induced in the mice via a trimethylhexanoyl-ferrocene supplemented (Fe) diet for 3 months, and the mice were treated daily with either: DFP (50 mg/kg), DFP (50 mg/kg) plus GTE (50 mg EGCG equivalent/kg), or GTE alone for 2 months. Plasma non-transferrin bound iron (NTBI), malondialdehyde (MDA), alanine aminotransferase (ALT), aspartate aminotransferase (AST), hepcidin and insulin; tissue iron and MDA were measured. DFP, GTE and GTE + DFP effectively decreased plasma MDA (p < 0.05), NTBI and ALT, and increased plasma hepcidin and insulin. All the treatments also reduced iron accumulation and MDA production in both the pancreas and liver in the mice. However, the combination therapy demonstrated no advantages over monotherapy. The findings suggest GTE improved liver and pancreatic ß-cell functions in iron-overloaded ß-thalassemia mice by diminishing redox iron and free radicals, while inhibiting lipid peroxidation. Consequently, there are indications that GTE holds significant potential for clinical use.

Bilateral auditory ossicular expansions in a child with beta-thalassemia major: Case report and literature review.

Marrow proliferation of the ossicular chain is a rare phenomenon. To date, only two other cases have described this rarity. We report a third paediatric case from Australia. A seven-year-old with thalassemia major demonstrated conductive impairment during surveillance for Deferasirox ototoxicity. Otitis media was assumed, however, CT scan of the petrous temporal bone revealed extramedullary haematopoiesis causing bilateral ossicular expansions and fixed conductive deficit. Reports of hearing loss in the thalassemia population focus on sensorineural impairment from iron chelation therapies. Clinicians should suspect ossicular deformation where treatment has been delayed, poorly controlled or conductive deficit persists without effusion.

Neurocognitive dysfunction in children with ß thalassemia major: psychometric, neurophysiologic and radiologic evaluation.

OBJECTIVE: To evaluate the impact of iron chelating drugs and serum ferritin on the neurocognitive functions of patients with ß thalassemia major (ß-TM), using psychometric, neurophysiologic and radiologic tests. METHODS: Eighty children with ß-TM were enrolled into the study and were compared to 40 healthy controls. All participants were evaluated by measuring serum ferritin, neurocognitive assessment by Benton Visual Retention Test, Wechsler Intelligence Scale for Children, Wisconsin Card Sort Test, P300 and magnetic resonance spectroscopy (MRS). RESULTS: WISC in our study showed that 40% of cases were borderline mental function as regards total IQ. Neurophysiologic tests were significantly impaired in patients compared to control group, with significant impairment in those receiving desferrioxamine (DFO). P300 amplitude was significantly lower in cases compared to controls (2.24 and 4.66 uv, respectively), recording the shortest amplitude in patients receiving DFO. Altered metabolic markers in the brain were detected by MRS in the form of reduced N-acetylaspartate to creatine ratio in 78.3% of our cases. There were significant correlations between psychometric tests and both neurophysiologic (P300) and radiologic (MRS) tests. CONCLUSION: ß-TM is associated with neurocognitive impairment that can be assessed by psychometric, neurophysiologic and radiologic tests. The role of hemosiderosis and iron chelation therapy on cognitive functioning still need more research. ABBREVIATIONS: ß-TM: beta thalassemia major; DFO: Dysferal; DFP: Deferiprone; DFX: Deferasirox; WISC: Wechsler Intelligence Scale for Children; VIQ: verbal IQ; PIQ: performance IQ; TIQ: total IQ; BVRT: Benton Visual Retention Test; WCST: Wisconsin Card Sort Test; MRS: Magnetic resonant spectroscopy; NAA/Cr ratio: N-acetylaspartate to creatine ratio.

Ischemia-modified albumin as a marker of vascular dysfunction and subclinical atherosclerosis in ß-thalassemia major.

BACKGROUND: Ischemia-modified albumin (IMA) is an altered type of serum albumin that forms under conditions of oxidative stress and an independent predictor of major adverse cardiovascular events. OBJECTIVES: To measure the levels of IMA in 45 children and adolescents with ß-thalassemia major (ß-TM) compared with 30 healthy controls and assess its relation to lipid peroxidation, vascular complications and subclinical atherosclerosis. METHODS: ß-TM patients without symptoms of heart disease were studied focusing on transfusion history, chelation therapy, serum ferritin, malondialdehyde (MDA) and IMA levels. Echocardiography was performed and carotid intima media thickness (CIMT) was assessed. RESULTS: IMA and MDA levels were significantly higher in ß-TM patients compared with controls (p < 0.001). IMA was higher among patients with heart disease, pulmonary hypertension risk and serum ferritin ≥2500 µg/l than those without. TM patients compliant to chelation had significantly lower IMA levels. IMA levels were positively correlated to MDA and CIMT while negatively correlated to ejection fraction and fractional shortening. CONCLUSION: Our results highlight the role of oxidative stress in the pathophysiology of vascular complications in thalassemia. IMA could be useful for screening of ß-TM patients at risk of cardiopulmonary complications and atherosclerosis because its alteration occurs in early subclinical disease.

Soluble fms-Like Tyrosine Kinase 1 as a Link Between Angiogenesis and Endothelial Dysfunction in Pediatric Patients With ß-Thalassemia Intermedia.

Endothelial damage has been implicated in the pathogenesis of vascular complications in ß-thalassemia intermedia (ß-TI). Soluble fms-like tyrosine kinase 1 (sFLT-1) is a member of the vascular endothelial growth factor receptor (VEGFR) family. Soluble fms-like tyrosine kinase 1 is an antiangiogenic protein that induces endothelial dysfunction by adhering to and inhibiting VEGF and placenta growth factor. The aim of this study was to assess the level of sFLT-1 in 35 children and adolescents with ß-TI, correlating it with markers of hemolysis and iron overload as well as cardiopulmonary complications. Patients were studied focusing on the history of cardiac disease, splenectomy, transfusion, chelation/hydroxyurea therapy, serum ferritin, and sFLT-1 levels. Echocardiography and measurement of carotid intima-media thickness (CIMT) were done for all participants. Soluble fms-like tyrosine kinase 1 was significantly higher in TI patients compared to the control group (median [interquartile range], 110 [80-155] pg/mL versus 70 [60-90] pg/mL; P < .001). Splenectomized patients and those who had pulmonary hypertension risk or heart disease had higher sFLT-1 levels than those without ( P < .001). The sFLT-1 cutoff value that differentiates patients with and without pulmonary hypertension risk or heart disease was determined. Soluble fms-like tyrosine kinase 1 was lower among patients who received chelation therapy and/or hydroxyurea. Significant positive relations were observed between sFLT-1 and lactate dehydrogenase, serum ferritin, liver iron concentration, tricuspid regurgitant jet velocity, and CIMT. We suggest that sFLT-1 represents a link between angiogenesis, endothelial dysfunction, and subclinical atherosclerosis. Measurement of sFLT-1 as a marker of vascular dysfunction in ß-TI may provide utility for early identification of patients at increased risk of cardiopulmonary complications.

Non-invasive MRI biomarkers for the early assessment of iron overload in a humanized mouse model of ß-thalassemia.

ß-thalassemia (ßT) is a genetic blood disorder causing profound and life threatening anemia. Current clinical management of ßT is a lifelong dependence on regular blood transfusions, a consequence of which is systemic iron overload leading to acute heart failure. Recent developments in gene and chelation therapy give hope of better prognosis for patients, but successful translation to clinical practice is hindered by the lack of thorough preclinical testing using representative animal models and clinically relevant quantitative biomarkers. Here we demonstrate a quantitative and non-invasive preclinical Magnetic Resonance Imaging (MRI) platform for the assessment of ßT in the γß0/γßA humanized mouse model of ßT. Changes in the quantitative MRI relaxation times as well as severe splenomegaly were observed in the heart, liver and spleen in ßT. These data showed high sensitivity to iron overload and a strong relationship between quantitative MRI relaxation times and hepatic iron content. Importantly these changes preceded the onset of iron overload cardiomyopathy, providing an early biomarker of disease progression. This work demonstrates that multiparametric MRI is a powerful tool for the assessment of preclinical ßT, providing sensitive and quantitative monitoring of tissue iron sequestration and cardiac dysfunction- parameters essential for the preclinical development of new therapeutics.

Genotoxic effect of iron overload and disease complications in transfused ß thalassaemic patients.

In previously reported studies, we observed significantly high genotoxicity biomarkers in regularly transfused thalassaemic patients, thus, in this study, we better investigated the genotoxic effect of iron overload and of thalassaemia complications, including their drug treatments. The assessment was performed in 64 regularly transfused thalassaemic patients using cytokinesis-block micronucleus and comet assays. All patients were splenectomised and undergoing iron chelation therapy. To reduce hypoxia-induced oxidative damage, the patients with haemoglobin levels <9.5 g/dL were excluded. Serum concentrations of ferritin, iron, transferrin and the percentage of transferrin saturation, as well as cardiac and hepatic T2* magnetic resonance imaging, were considered to evaluate serum and organ siderosis.All genotoxic biomarkers significantly differed between patients and healthy subjects. Iron intake via blood transfusions was inversely related to percentage of DNA in tail. The disease complications affecting endpoints were active Hepatitis C virus infection, drug therapy for osteoporosis (i.e. bisphosphonates) and hormone replacement therapy for hypogonadism.The results, highlighting the combined effect of iron overload and, mainly, disease complications, including their respective pharmacological treatments, confirmed the increased cancer risk in thalassaemic patients.

Iron distribution and histopathological study of the effects of deferoxamine and deferiprone in the kidneys of iron overloaded ß-thalassemic mice.

Renal glomerular and tubular dysfunctions have been reported with high prevalence in ß-thalassemia. Iron toxicity is implicated in the kidney damage, which may be reversed by iron chelation therapy. To mimic heavy iron overload and evaluate the efficacy of iron chelators in the patients, iron dextran (180mg iron/mouse) was intraperitoneally (i.p.) injected in heterozygous ß-globin knockout mice ((mußth-3/+), BKO) and wild type mice (C57BL/6J, WT) over a period of 2 weeks, followed by daily i.p. injection of deferoxamine (DFO) or deferiprone (L1) for 1 week. In BKO mice, iron preferentially accumulated in the proximal tubule with a grading score of 0-1 and increased to grade 3 after iron loading. In contrast, iron mainly deposited in the glomerulus and interstitial space in iron overloaded WT mice. Increased levels of kidney lipid peroxidation, glomerular and medullar damage and fibrosis in iron overloaded mice were reversed by treatment with iron chelators. L1 showed higher efficacy than DFO in reduction of glomerular iron, which was supported by a significantly decreased the amount of glomerular damage. Notably, DFO and L1 demonstrated a distinct pattern of iron distribution in the proximal tubule of BKO mice. In conclusion, chelation therapy has beneficial effects in iron-overloaded kidneys. However, the defect of kidney iron metabolism in thalassemia may be a determining factor of the treatment outcome in individual patients.

Quantification of Myocardial Extracellular Volume Fraction with Cardiac MR Imaging in Thalassemia Major.

Purpose To quantify myocardial extracellular volume (ECV) by using cardiac magnetic resonance (MR) imaging in thalassemia major and to investigate the relationship between ECV and myocardial iron overload. Materials and Methods With institutional review board approval and informed consent, 30 patients with thalassemia major (mean age ± standard deviation, 34.6 years ± 9.5) and 10 healthy control subjects (mean age, 31.5 years ± 4.4) were prospectively recruited (clinicaltrials.gov identification number NCT02090699). Nineteen patients (63.3%) had prior myocardial iron overload (defined as midseptal T2* < 20 msec on any prior cardiac MR images). Cardiac MR imaging at 1.5 T included cine steady-state free precession for ventricular function, T2* for myocardial iron quantification, and unenhanced and contrast material-enhanced T1 mapping. ECV was calculated with input of the patient's hematocrit level. Peak systolic global longitudinal strain by means of speckle tracking was assessed with same-day transthoracic echocardiography. Statistical analysis included use of the two-sample t test, Fisher exact test, and Spearman correlation. Results Unenhanced T1 values were significantly lower in patients with prior myocardial iron overload than in control subjects (850.3 ± 115.1 vs 1006.3 ± 35.4, P < .001) and correlated strongly with T2* values (r = 0.874, P < .001). Patients with prior myocardial iron overload had higher ECV than did patients without iron overload (31.3% ± 2.8 vs 28.2% ± 3.4, P = .030) and healthy control subjects (27.0% ± 3.1, P = .003). There was no difference in ECV between patients without iron overload and control subjects (P = .647). ECV correlated with lowest historical T2* (r = -0.469, P = .010) but did not correlate significantly with left ventricular ejection fraction (r = -0.216, P = .252) or global longitudinal strain (r = -0.164, P = .423). Conclusion ECV is significantly increased in thalassemia major and is associated with myocardial iron overload. These abnormalities may potentially reflect diffuse interstitial myocardial fibrosis. (©) RSNA, 2015 Online supplemental material is available for this article.

Glutathione S-transferase gene polymorphism: Relation to cardiac iron overload in Egyptian patients with Beta Thalassemia Major.

OBJECTIVES: Estimating the prevalence of glutathione S-transferase gene polymorphism (GSTM1) null genotype among patients with beta thalassemia major (ß-TM) in relation to myocardial status assessed by tissue Doppler and cardiac siderosis assessed by cardiac magnetic resonance imaging (MRI) T2*. METHODS: Hundred patients with ß-TM and 100 healthy controls were enrolled. Complete blood count (CBC), mean serum ferritin and GSTM1 genotyping, echocardiography, tissue Doppler, and cardiac MRI T2* were done. RESULTS: Serum ferritin ranged from 1200 to 8000 ng/ml, and mean T2* value was 27.10 ± 11.20 ms. Of patients, 68 (68%) had no cardiac siderosis, while 24 (24%) with mild to moderate, and 8 (8%) with sever cardiac siderosis. T2* values were not correlated with serum ferritin (r = -0.09, P = 0.50). GSTM1 null genotype was prevalent in 46% of patients and 40% of controls (P = 0.69). Patients with null genotype had significantly shorter T2* (P = 0.001), higher left ventricular end-diastolic diameter (P = 0.002), and shorter ejection time (P = 0.005) with no significant relation to serum ferritin (P = 0.122). GSTM1 null genotype was the only predictor for cardiac iron overload (P = 0.002). DISCUSSION: Serum ferritin concentrations have been shown to correlate poorly with all stages of cardiac dysfunction. Low cardiac MRI T2* values occur in patients with ß-TM despite good chelation therapy, suggesting a possible role of genetic factors in cardiac siderosis. CONCLUSION: GSTM1 null genotype is significantly associated with cardiac iron overload independent of serum ferritin in Egyptian patients with ß-TM.