Impact of iron assessment by MRI

Pancreatic iron in pediatric transfusion-dependent beta-thalassemia patients: A longitudinal MRI study

BACKGROUND

In pediatric transfusion-dependent thalassemia (TDT) patients, we evaluated the prevalence, pattern, and clinical associations of pancreatic siderosis and the changes in pancreatic iron levels and their association with baseline and changes in total body iron balance.

PROCEDURE

We considered 86 pediatric TDT patients consecutively enrolled in the Extension-Myocardial Iron Overload in Thalassemia Network. Iron overload (IO) was quantified by R2* magnetic resonance imaging (MRI).

RESULTS

Sixty-three (73%) patients had pancreatic IO (R2* > 38 Hz). Global pancreas R2* values were significantly correlated with mean serum ferritin levels, MRI liver iron concentration (LIC) values, and global heart R2* values. Global pancreas R2* values were significantly higher in patients with altered versus normal glucose metabolism. Thirty-one patients also performed the follow-up MRI at 18 ± 3 months. Higher pancreatic R2* values were detected at the follow-up, but the difference versus the baseline MRI was not significant. The 20% of patients with baseline pancreatic IO showed no pancreatic IO at the follow-up. The 46% of patients without baseline pancreatic IO developed pancreatic siderosis. The changes in global pancreas R2* between the two MRIs were not correlated with baseline serum ferritin levels, baseline, final, and changes in MRI LIC values, or baseline pancreatic iron levels.

CONCLUSIONS

In children with TDT, pancreatic siderosis is a frequent finding associated with hepatic siderosis and represents a risk factor for myocardial siderosis and alterations of glucose metabolism. Iron removal from the pancreas is exceptionally challenging and independent from hepatic iron status.

A pilot study to evaluate clinical factors associated with iron and ferritin elevations during pediatric extracorporeal membrane oxygenation

Introduction: Elevations in serum ferritin and serum iron occur during pediatric extracorporeal membrane oxygenation (ECMO). Previous reports attribute the elevation to frequent red blood cell transfusions and/or hemolysis. Chronic transfusion can cause iron deposition in tissues leading to multisystem organ dysfunction. This study aims identify clinical factors associated with elevated ferritin and iron in pediatric ECMO patients, along with post-decannulation magnetic resonance imaging (MRI) assessment of iron deposition in liver and brain.Methods: Prospective, pilot study, using descriptive statistics to investigate potential associations between patient characteristics, serum ferritin and iron levels, and post-decannulation hepatic and basal ganglia iron deposition.Results: In this study, nine patients (100%) had elevated serum ferritin levels during ECMO. High ferritin levels were more common with veno-arterial than with veno-venous cannulation (p = 0.026) and were also associated with high plasma free hemoglobin levels (p < 0.001). Five patients presented with elevated serum iron levels. High serum iron levels were associated with higher daily (p = 0.016) and cumulative transfusion volumes (p = 0.013) as well ECMO duration beyond 7 days. MRI scans were performed on three patients with no evidence of abnormal iron deposition detected in the liver or brain.Conclusions: This pilot study shows that during pediatric ECMO, elevations in serum ferritin and serum iron occur and those elevations may be related to the cannulation modality, ECMO duration, amount of hemolysis, and volume of red blood cell transfusions. Further investigation is warranted to fully understand the implications of elevated serum iron and ferritin in pediatric ECMO.

Αlpha-thalassemia: A practical overview

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

Prognostic Role of Multiparametric Cardiac Magnetic Resonance in Neo Transfusion-Dependent Thalassemia

BACKGROUND

We prospectively evaluated the predictive value of multiparametric cardiac magnetic resonance (CMR) for cardiovascular complications in non-transfusion-dependent β-thalassemia (β-NTDT) patients who started regular transfusions in late childhood/adulthood (neo β-TDT).

METHODS

We considered 180 patients (38.25 ± 11.24 years; 106 females). CMR was used to quantify cardiac iron overload, biventricular function, and atrial dimensions, and to detect left ventricular (LV) replacement fibrosis.

RESULTS

During a mean follow-up of 76.87 ± 41.60 months, 18 (10.0%) cardiovascular events were recorded: 2 heart failures, 13 arrhythmias (10 supraventricular), and 3 cases of pulmonary hypertension. Right ventricular (RV) end-diastolic volume index (EDVI), RV mass index (MI), LV replacement fibrosis, and right atrial (RA) area index emerged as significant univariate prognosticators of cardiovascular complications. The low number of events prevented us from performing a multivariable analysis including all univariable predictors simultaneously. Firstly, a multivariable analysis including the two RV size parameters (mass and volume) was carried out, and only the RV MI was proven to independently predict cardiovascular diseases. Then, a multivariable analysis, including RV MI, RA atrial area, and LV replacement fibrosis, was conducted. In this model, RV MI and LV replacement fibrosis emerged as independent predictors of cardiovascular outcomes (RV MI: hazard ratio (HR) = 1.18; LV replacement fibrosis: HR = 6.26).

CONCLUSIONS

Our results highlight the importance of CMR in cardiovascular risk stratification.

Research on the clinical factors of cardiac iron deposition in children with beta-thalassemia major

Magnetic resonance imaging (MRI) T2* is the gold standard for detecting iron deposition in cardiac tissue, but the technique has limitations and cannot be fully performed in paediatric thalassemia patients. The aim of this study was to analyse clinical data to identify other predictors of cardiac iron deposition. A retrospective analysis was performed on 370 children with β-TM. According to the cardiac MRI results, patients were allocated to a cardiac deposition group and noncardiac deposition group. Multivariate analysis revealed that genotype and corrected QT interval were associated with cardiac iron deposition, indicating that the-β0/β0 genotype conferred greater susceptibility to cardiac iron deposition. Receiver operating characteristic curve (ROC) analysis was performed, and the area under the curve (AUC) of genotype was 0.651. The AUC for the corrected QT interval was 0.711, at a cut-off value of 418.5 ms. ROC analysis of the combined genotype and corrected QT interval showed an AUC of 0.762 with 81.3% sensitivity and 64.7% specificity. Compared to patients with the β+/β+ and β0β+ genotypes, β0β0 children with β-TM were more likely to have cardiac iron deposition.  Conclusion: The genotype and QTc interval can be used to predict cardiac iron deposition in children with β-TM who are unable to undergo MRI T2 testing.

Iron, glucose and fat metabolism and obesity: an intertwined relationship

A bidirectional relationship exists between adipose tissue metabolism and iron regulation. Total body fat, fat distribution and exercise influence iron status and components of the iron-regulatory pathway, including hepcidin and erythroferrone. Conversely, whole body and tissue iron stores associate with fat mass and distribution and glucose and lipid metabolism in adipose tissue, liver, and muscle. Manipulation of the iron-regulatory proteins erythroferrone and erythropoietin affects glucose and lipid metabolism. Several lines of evidence suggest that iron accumulation and metabolism may play a role in the development of metabolic diseases including obesity, type 2 diabetes, hyperlipidaemia and non-alcoholic fatty liver disease. In this review we summarise the current understanding of the relationship between iron homoeostasis and metabolic disease.

Free-Breathing Liver Fat, R₂* and B₀ Field Mapping Using Multi-Echo Radial FLASH and Regularized Model-Based Reconstruction

This work introduced a stack-of-radial multi-echo asymmetric-echo MRI sequence for free-breathing liver volumetric acquisition. Regularized model-based reconstruction was implemented in Berkeley Advanced Reconstruction Toolbox (BART) to jointly estimate all physical parameter maps (water, fat, R2∗ , and B0 field inhomogeneity maps) and coil sensitivity maps from self-gated k -space data. Specifically, locally low rank and temporal total variation regularization were employed directly on physical parameter maps. The proposed free-breathing radial technique was tested on a water/fat & iron phantom, a young volunteer, and obesity/diabetes/hepatic steatosis patients. Quantitative fat fraction and R2∗ accuracy were confirmed by comparing our technique with the reference breath-hold Cartesian scan. The multi-echo radial sampling sequence achieves fast k -space coverage and is robust to motion. Moreover, the proposed motion-resolved model-based reconstruction allows for free-breathing liver fat and R2∗ quantification in multiple motion states. Overall, our proposed technique offers a convenient tool for non-invasive liver assessment with no breath holding requirement.

Tissue iron distribution in patients with anemia of inflammation: Results of a pilot study

Anemia of inflammation (AI) is frequently present in subjects with inflammatory disorders, primarily caused by inflammation-driven iron retention in macrophages. So far, only limited data on qualitative and quantitative estimates of tissue iron retention in AI patients exist. We performed a prospective cohort study analyzing splenic, hepatic, pancreatic, and cardiac iron content with MRI-based R2*-relaxometry in AI patients, including subjects with concomitant true iron deficiency (AI+IDA) hospitalized between 05/2020-01/2022. Control groups were individuals without inflammation. Spleen R2* values in AI patients with ferritin ≤200 μg/L (AI+IDA) were comparable with those found in controls. In AI patients with ferritin >200 μg/L, spleen (47.6 s^-1 vs. 19.3 s^-1 , p < .001) and pancreatic R2* values (32.5 s^-1 vs. 24.9 s^-1 , p = .011) were significantly higher compared with controls, while liver and heart R2*-values did not differ. Higher spleen R2* values were associated with higher ferritin, hepcidin, CRP, and IL-6 concentrations. Spleen R2* values normalized in AI patients after recovery (23.6 s^-1 vs. 47.6 s^-1 , p = .008), while no changes were found in patients with baseline AI+IDA. This is the first study investigating tissue iron distribution in patients with inflammatory anemia and AI with concomitant true iron deficiency. The results support the findings in animal models demonstrating iron retention in macrophages, which are primarily accumulating in the spleen under inflammatory conditions. MRI-related iron measurement may help to better characterize actual iron needs and to define better biomarker thresholds in the diagnosis of true ID in patients with AI. It may qualify as a useful diagnostic method to estimate the need for iron supplementation and to guide therapy.

Prognostic value of multiparametric cardiac magnetic resonance in sickle cell patients

The aim of this multicenter study was to prospectively assess the predictive value of multiparametric cardiac magnetic resonance (CMR) for cardiovascular complications in sickle cell disease (SCD) patients. Among all patients with hemoglobinopathies consecutively enrolled in the Myocardial Iron Overload in Thalassemia (MIOT) Network, we selected 102 SCD patients (34.38 ± 12.67 years, 49 females). Myocardial iron overload (MIO) was measured by the multislice multiecho T2* technique. Atrial dimensions and biventricular function parameters were quantified by cine images. Late gadolinium enhancement (LGE) images were acquired to detect focal myocardial fibrosis. At baseline CMR, only two patients had significant MIO (global heart T2* < 20 ms). During a mean follow-up of 63.01 ± 24.95 months, 11 cardiovascular events (10.8%) were registered: 3 pulmonary hypertension, 2 supraventricular arrhythmias, 1 heart failure, 1 death for heart failure, 1 pulmonary embolism, 1 peripheral vascular disease, 1 transient ischemic attack, and 1 death after acute chest syndrome. In the multivariate analysis, the independent CMR predictors of cardiovascular events were left ventricular (LV) ejection fraction (hazard ratio-HR = 0.88; p = 0.025) and right ventricular (RV) mass index (HR = 1.09; p = 0.047). According to the receiver-operating characteristic curve analysis for adverse events, an LV ejection fraction < 58.9% and an RV mass index > 31 g/m² were optimal cut-off values. Reduced left ventricular ejection fraction and increased right ventricular mass index showed a significant prognostic value in patients with SCD. Our data seem to suggest that CMR may be added as a screening tool for identifying SCD patients at high risk for cardiopulmonary and vascular diseases.

Protein-Inspired Polymers with Metal-Site-Regulated Ordered Conformations

Metal ions play critical roles in facilitating peptide folding and inducing conformational transitions, thereby impacting on the biological activity of many proteins. However, the effect of metal sites on the hierarchical structures of biopolymers is still poorly understood. Herein, inspired by metalloproteins, we report an order-to-order conformational regulation in synthetic polymers mediated by a variety of metal ions. The copolymers are decorated with clinically available desferrioxamine (DFO) as an exogenous ligand template, which presents a geometric constraint toward peptide backbone via short-range hydrogen bonding interactions, thus dramatically altering the secondary conformations and self-assembly behaviors of polypeptides and allowing for a controllable β-sheet to α-helix transition modulated by metal-ligand interactions. These metallopolymers could form ferritin-inspired hierarchical structures with high stability and membrane activity for efficient brain delivery across the blood-brain barrier (BBB) and long-lasting magnetic resonance imaging (MRI) in vivo.

The role of MRI-R2* in the detection of subclinical pancreatic iron loading among transfusion-dependent sickle cell disease patients and correlation with hepatic and cardiac iron loading

Objectives

Pancreatic reserve could be preserved by early assessment of pancreatic iron overload among transfusion-dependent sickle cell disease (SCD) patients. This study aimed to measure pancreatic iron load and correlate its value with patients’ laboratory and radiological markers of iron overload.

Materials and methods

Sixty-six SCD children and young adults underwent MRI T2* relaxometry using a simple mathematical spreadsheet and laboratory assessment.

Results

The results indicated moderate-to-severe hepatic iron overload among 65.2% of studied cases. None had cardiac iron overload. Normal-to-mild iron overload was present in the pancreas in 86% of cases, and 50% had elevated serum ferritin > 2500 ug/L. There was no significant correlation between pancreatic R2* level, serum ferritin, and hepatic iron overload. Patients with higher levels of hemolysis markers and lower pre-transfusion hemoglobin levels showed moderate-to-severe pancreatic iron overload.

Conclusion

Chronically transfused patients with SCD have a high frequency of iron overload complications including pancreatic iron deposition, thereby necessitating proper monitoring of the body’s overall iron balance as well as detection of extrahepatic iron depositions.

Liver iron quantification in children and young adults: comparison of a volumetric multi-echo 3-D Dixon sequence with conventional 2-D T2* relaxometry

BACKGROUND

Magnetic resonance imaging (MRI)-based liver iron quantification is the standard of care to guide chelation therapy in children at risk of hemochromatosis. T2* relaxometry is the most widely used technique but requires third-party software for post-processing. Vendor-provided three-dimensional (3-D) multi-echo Dixon techniques are now available that allow inline/automated post-processing.

OBJECTIVE

The purpose of our study was to evaluate the diagnostic accuracy of a volumetric multi-echo Dixon technique using conventional T2* relaxometry as the reference standard in a pediatric and young adult population.

MATERIALS AND METHODS

In this retrospective study, we queried the radiology information system to identify all MRIs performed for liver iron quantification from July 2015 to January 2020. All patients had undergone T2* relaxometry on a 1.5-tesla (T) scanner for liver iron concentration (LIC) estimation. In addition, a 3-D multi-echo Dixon was performed using Siemens Healthineers LiverLab (Erlangen, Germany). Two readers independently estimated liver R2* and T2* on the multi-echo Dixon by drawing free-hand regions of interest on the scanner-generated R2* and T2* maps. Conventional T2*-relaxometry-based LIC was the reference standard. We estimated interobserver agreement by concordance correlation coefficient (CCC). We used Bland-Altman analysis and Pearson correlation coefficient (r) to compare LIC by the two methods.

RESULTS

Fifty-four MRIs on 38 patients (22 females) were available for analysis. Mean patient age was 11.8 years (standard deviation [SD] 5.3 years). Reference standard LIC ranged 1.1-21.1 (median 6.8) mg/g dry weight of liver. The concordance between readers for T2* estimation using 3-D multi-echo Dixon was substantial (CCC 0.99, confidence interval 0.99-1.00). Bland-Altman plot showed that all observations were clustered around the zero bias line if the LIC average was ≤8 mg/g, and r was very strong (reader 1 r=0.93, reader 2 r=0.92, both P-values <0.001). With increasing LIC, there was a pattern of poor agreement on the Bland-Altman plot, with observations crossing the lower limits of agreement, and r was very weak (reader 1 r=0.05, P-value 0.84; reader 2 r=0.17, P-value 0.44).

CONCLUSION

Vendor-based 3-D multi-echo Dixon allows for excellent interobserver correlation in liver T2* estimation. LIC estimated by this method has a very strong correlation with conventional T2* relaxometry if liver iron overload is mild-moderate (LIC ≤8 mg/g).

Dual gradient echo in-phase and out of phase sequences in assessment of hepatic iron overload in patients with beta-thalassemia, would be better?

PURPOSE

To evaluate the diagnostic accuracy of the dual gradient-echo (GRE) in- and out-of-phase sequences as a quantitative tool for hepatic iron overload in comparison with MRI R2* relaxometry in paediatric patients with beta-thalassemia.

METHOD

Sixty-three patients with beta-thalassemia major (transfusion-dependent) or beta-thalassemia intermedia (transfusion- and non-transfusion-dependent) were referred from the paediatric department (haematology unit) to the radiology department at a university hospital. The paediatrician conducted a clinical examination for the studied group, assessed their laboratory data, conducted R2* relaxometry and dual gradient echo sequences to calculate R2* and relative signal intensity index at the axial mid-section of the liver, and studied their correlation. A 1.5 Tesla MR scanner was used (Achieva; Philips Medical Systems, the Netherlands). Data were fed to the computer and analysed using the IBM SPSS software package version 20.0 (Armonk, NY: IBM Corp). The Kolmogorov-Smirnov test was used to verify the normality of distribution. The significance of the results was determined at the 5% level. The Chi-square, Fisher's exact correction, Pearson coefficient, and Bland-Altman tests were used.

RESULTS

Dual gradient-echo in- and out-of-phase sequences using visual assessment accurately assessed 93.65% of our patient group with hepatic iron overload. A significant correlation was found between the relative signal intensity index and hepatic MRI R2* relaxometry (p < 0.001, r = 0.861).

CONCLUSIONS

Dual gradient-echo in and out-of-phase sequences are good imaging tools for hepatic iron detection and quantification. These sequences showed good correlation with R2* relaxometry (r = 0.861, p < 0.001).

Cardiac T2* magnetic resonance analysis of membranous interventricular septum in assessment of cardiac iron overload in pediatric thalassemia patients: A pilot study

Background:

Cardiac iron deposition in transfusion-dependent thalassemia patients is patchy in distribution.

Purpose:

The purpose of this study is to assess the correlation between T2* matrices of membranous interventricular septum (MIVS) and T2* values of muscular interventricular septum (IVS) on magnetic resonance imaging (MRI) and to evaluate the relationship of myocardial T2* at these two locations with MRI-estimated liver iron concentrations (LIC) and electrocardiographic (ECG) parameters.

Material and Methods:

MRI of heart and liver was performed in 16 consecutive pediatric patients of transfusion-dependent thalassemia major to calculate liver iron concentration and T2* time of membranous and muscular IVS. ECG parameters of these patients were charted and correlated with MRI parameters.

Results:

No significant correlation between T2* values of muscular IVS and MIVS was observed. Mean T2* of MIVS (9.8 ms) was significantly lower than that of muscular IVS (26.9 ms). T2* of MIVS correlated strongly with LIC where as a weak correlation was observed between T2* of IVS and LIC. Significantly higher mean QTc (corrected QT interval) value (439.86 ms) was seen in patients with T2* IVS <20 ms.

Conclusion:

Addition of T2* analysis of MIVS to the existing MRI protocol, consisting of muscular IVS analysis, may offer a more sensitive estimation of cardiac iron overload.

Pancreatic MR imaging and endocrine complications in patients with beta-thalassemia: a single-center experience

Iron deposition in various organs can cause endocrine complications in patients with transfusion-dependent beta-thalassemia. The aim was to investigate the relationship between endocrine complications and pancreatic iron overload using magnetic resonance imaging (MRI). Forty patients with transfusion-dependent thalassemia (TDT) were enrolled in the study. The magnetic resonance imagings of the patients were performed using a 1.5 Tesla Philips MRI scanner. Two out of three patients had at least one clinical endocrine complication. The rate of iron deposition was 62.5% in liver, and 45% in pancreas tissue, and was 12.5% in heart tissue. Pancreatic T2* and hepatic T2* values were significantly positively correlated (p = 0.006). Pancreatic T2* and ferritin were significantly negatively correlated (p = 0.03). Cardiac T2* values were negatively correlated with fasting blood glucose (p = 0.03). Patients with short stature had significantly higher cardiac iron burden (22.3 vs. 36.6 T2*ms; p 0.01), and patients with hypothyroidism had higher liver iron concentrations (9.9 vs. 6.4 LIC mg/g; p = 0.05). The ferritin level of 841 ng/mL and liver iron concentration (LIC) value of 8.7 mg/g were detected as the threshold level for severe pancreatic iron burden (AUC 70%, p:0.04, AUC 80%, p = 0.002, respectively). Moreover, males were found to have decreased pancreas T2* values compared with the values in females (T2* 19.3 vs. 29.9, p = 0.05). Patients with higher ferritin levels over than 840 ng/mL should be closely monitored for pancreatic iron deposition, and patients with endocrine complications should be assessed in terms of cardiac iron burden.

Evaluation of iron overload by cardiac and liver T2* in β-thalassemia: Correlation with serum ferritin, heart function and liver enzymes

Introduction: In this study, we aimed to assess the relationship of cardiac and hepatic T2* magnetic resonance imaging (MRI) values as a gold standard for detecting iron overload with serum ferritin level, heart function, and liver enzymes as alternative diagnostic methods. Methods: A total 58 patients with beta-thalassemia major who were all transfusion dependent were evaluated for the study. T2* MRI of heart and liver, echocardiography, serum ferritin level, and liver enzymes measurement were performed. The relationship between T2* MRI findings and other assessments were examined. Cardiac and hepatic T2* findings were categorized as normal, mild, moderate, and severe iron overload. Results: 22% and 11% of the patients were suffering from severe iron overload in heart and liver, respectively. The echocardiographic findings were not significantly different among different iron load categories in heart or liver. ALT level was significantly higher in patient with severe iron overload than those with normal iron load in heart (P =0.005). Also, AST level was significantly lower in normal iron load group than mild, moderate, and severe iron load groups in liver (P <0.05). The serum ferritin level was significantly inversely correlated with cardiac T2* values (r = -0.34, P =0.035) and hepatic T2* values (r = -0.52, P =0.001). Conclusion: Cardiac and hepatic T2* MRI indicated significant correlation with serum ferritin level.

Risk factors for endocrine complications in transfusion-dependent thalassemia patients on chelation therapy with deferasirox: a risk assessment study from a multicentre nation-wide cohort

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.

Pituitary Iron Deposition and Endocrine Complications in Patients with β-Thalassemia: From Childhood to Adulthood

The endocrinological complications are a great concern in transfusion-dependent β-thalassemia (β-thal) patients. The pituitary iron deposition is regarded as the main cause of hormonal changes in thalassemic patients. In this study, our aim was to explore the association between endocrinological complications and pituitary iron overload by magnetic resonance imaging (MRI). Fifty transfusion-dependent thalassemia (TDT) patients were recruited for the study. Pituitary MRIs of patients were taken using a 1.5 Tesla Philips MRI machine. There was at least one clinical endocrine complication in two of three patients. The iron accumulation was moderate in the liver (60.0%) and was mild in hypophysis (16.0%) and in heart (8.0%). The hypogonadism and diabetes mellitus (DM) were not seen with a significantly increased pituitary iron burden. The hypogonadism was related to cardiac iron deposition (p = 0.04). The short stature was associated with a hepatic iron overload (p = 0.05). The conventional follow-up of patients with TDT might be inadequate and screening of patients with MRI of hypophysis along with heart and liver leads to better results.

Early detection of ventricular dysfunction by tissue Doppler echocardiography related to cardiac iron overload in patients with thalassemia

Cardiac T2* MRI is used as a gold standard for cardiac iron quantification in patients with transfusion-dependent thalassemia (TDT). We hypothesized that left ventricular (LV) diastolic dysfunction would reflect the severity of iron overload and can serve as an early detection of cardiac iron deposits. A study was conducted on all patients with TDT. Hemoglobin, serum ferritin and non-transferrin bound iron, together with a complete echocardiography and cardiac T2* MRI, were performed on all patients. Seventy-seven patients with TDT were enrolled (median age 14 years). In the patient group with a mean serum ferritin of > 2500 ng/mL during the past 12 months, there were more patients with severe cardiac iron deposits than in the group with a mean serum ferritin of ≤ 2500 ng/mL. Diastolic dysfunction was absent in all patients with a serum ferritin of < 1000 ng/mL. All patients with cardiac T2* ≤ 20 ms had grade III LV diastolic dysfunction. However, twenty-one percent of patients with cardiac T2* > 20 ms had LV diastolic dysfunction. The differences observed in pulmonary vein atrial reversal duration and mitral A-wave (PVAR-MVA) duration ≥ - 1 ms and an E/E' ratio ≥ 11 were proven to be the associated factors with the cardiac T2* ≤ 20 ms. Increased PVAR-MVA duration and increased E/E' ratio reliably reflected a severe iron overload, according to a cardiac T2* in patients with TDT. LV diastolic dysfunction can occur prior to severe cardiac iron deposition. Tissue Doppler echocardiography has the potential for the early detection of cardiac involvement in patients with TDT .

Moxibustion with deferasirox results in safe, accelerated, and sustained cardiac iron chelation for a young Diamond Blackfan Anemia patient: An integrative case report

Diamond Blackfan Anemia (DBA) is a rare blood disorder of bone marrow failure typically identified in the first year of life. Due to treatment limitations, nearly all DBA patients are reliant upon chronic red cell infusion for some period of their lives. Repeat blood transfusion invariably leads to iron overload, which creates significant and life-threatening side effects. In this case report, a female child of 2 years and 8 months with DBA was diagnosed via T2* MRI imaging with potentially emergent levels of cardiac iron overload as a result of chronic red cell infusion. According to Chinese, Japanese, and integrative medicine principles, moxibustion was applied externally in conjunction with the prescribed oral chelation agent, deferasirox (DFX), over a period of six months. Analysis of repeat imaging at six months showed complete removal of cardiac iron and a one-third decrease in hepatic iron. In addition, there was no evidence of known risks to high-dose chelation, including renal, aural, or ocular damage. Follow-up examination two years after initial imaging showed no evidence of cardiac iron deposition with hepatic iron levels below minimum levels recommended for chelation despite the medical necessity of continued red cell infusion. This case study suggests that an integrative medical approach combining DFX with moxibustion may safely accelerate and sustain iron chelation for transfusion-dependent DBA patients. Recommendations for a successful approach to integrative iron chelation are provided in the case discussion.

Growth hormone therapy for people with thalassaemia

BACKGROUND

Thalassaemia is a recessively-inherited blood disorder that leads to anaemia of varying severity. In those affected by the more severe forms, regular blood transfusions are required which may lead to iron overload. Accumulated iron from blood transfusions may be deposited in vital organs including the heart, liver and endocrine organs such as the pituitary glands which can affect growth hormone production. Growth hormone deficiency is one of the factors that can lead to short stature, a common complication in people with thalassaemia. Growth hormone replacement therapy has been used in children with thalassaemia who have short stature and growth hormone deficiency. This review on the role of growth hormone was originally published in September 2017 and updated in April 2020.

OBJECTIVES

To assess the benefits and safety of growth hormone therapy in people with thalassaemia.

SEARCH METHODS

We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. Date of latest search: 14 November 2019. We also searched the reference lists of relevant articles, reviews and clinical trial registries. Date of latest search: 06 January 2020.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials comparing the use of growth hormone therapy to placebo or standard care in people with thalassaemia of any type or severity.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials for inclusion. Data extraction and assessment of risk of bias were also conducted independently by two authors. The certainty of the evidence was assessed using GRADE criteria.

MAIN RESULTS

We included one parallel trial conducted in Turkey. The trial recruited 20 children with homozygous beta thalassaemia who had short stature; 10 children received growth hormone therapy administered subcutaneously on a daily basis at a dose of 0.7 IU/kg per week and 10 children received standard care. The overall risk of bias in this trial was low except for the selection criteria and attrition bias which were unclear. The certainty of the evidence for all major outcomes was moderate, the main concern was imprecision of the estimates due to the small sample size leading to wide confidence intervals. Final height (cm) (the review's pre-specified primary outcome) and change in height were not assessed in the included trial. The trial reported no clear difference between groups in height standard deviation (SD) score after one year, mean difference (MD) -0.09 (95% confidence interval (CI) -0.33 to 0.15 (moderate-certainty evidence). However, modest improvements appeared to be observed in the following key outcomes in children receiving growth hormone therapy compared to control (moderate-certainty evidence): change between baseline and final visit in height SD score, MD 0.26 (95% CI 0.13 to 0.39); height velocity, MD 2.28 cm/year (95% CI 1.76 to 2.80); height velocity SD score, MD 3.31 (95% CI 2.43 to 4.19); and change in height velocity SD score between baseline and final visit, MD 3.41 (95% CI 2.45 to 4.37). No adverse effects of treatment were reported in either group; however, while there was no clear difference between groups in the oral glucose tolerance test at one year, fasting blood glucose was significantly higher in the growth hormone therapy group compared to control, although both results were still within the normal range, MD 6.67 mg/dL (95% CI 2.66 to 10.68). There were no data beyond the one-year trial period.

AUTHORS' CONCLUSIONS

A small single trial contributed evidence of moderate certainty that the use of growth hormone for a year may improve height velocity of children with thalassaemia although height SD score in the treatment group was similar to the control group. There are no randomised controlled trials in adults or trials that address the use of growth hormone therapy over a longer period and assess its effect on final height and quality of life. The optimal dosage of growth hormone and the ideal time to start this therapy remain uncertain. Large well-designed randomised controlled trials over a longer period with sufficient duration of follow up are needed.

Long-term improvement in cardiac magnetic resonance in β-thalassemia major patients treated with deferasirox extends to patients with abnormal baseline cardiac function

The management of iron overload in thalassemia has changed dramatically since the implementation of magnetic resonance imaging, which allows detection of preclinical iron overload and prevention of clinical complications. This study evaluated the effect of deferasirox (DFX), the newest once-daily oral chelator, on cardiac function, iron overload and cardiovascular events over a longer follow up in a "real world" setting. Longitudinal changes in cardiac magnetic resonance T2*, cardiac function parameters and cardiovascular clinical events were assessed in a cohort of 98 TM patients exposed to DFX for a mean of 6.9 years (range 1.8-11.6 years). No cardiac death or incident heart failure occurred. Cardiac T2* significantly increased (+2.6 ± 11.9 msec; P = 0.035) in the whole population, with a significantly greater increase (+11.6 ± 15.5 msec, P = 0.019) in patients with cardiac iron overload (T2* <20 ms). A significant improvement in left-ventricular ejection fraction (LVEF) (from 50.6 ± 6 to 60.2 ± 5; P = 0.001) was observed in 11 (84.6%) out of 13 patients who normalized cardiac function (LVEF >56%). Arrhythmias were the most frequent cardiac adverse event noted but none led to DFX discontinuation. Our data indicate that DFX is effective in maintaining cardiac iron level in the normal range and in improving cardiac iron overload. No heart failure or cardiac death was reported over this longer observation up to 12 years. For the first time, a DFX-induced improvement in LVEF was observed in a subgroup of patients with abnormal cardiac function at baseline, a preliminary observation which deserves further evaluation.

Association of serum asymmetric dimethyl-arginine and troponin I levels as a risk of myocardial infarction in thalassemia

BACKGROUND

The current study evaluated level of serum asymmetric dimethylarginine (ADMA) and its association to cardiac biomarkers in thalassemia patients for early diagnosis of abnormality in myocardial infarction.

SUBJECTS AND METHODS

This study was conducted on 80 subjects divided into four groups each with 20 subjects. Group I: Control: healthy subjects. Group II: Myocardial infarction: Patients with elevated serum troponin T. Group III: thalassemia patients. Group IV: thalassemia with myocardial infarction patients: Included 20 thalassemia patients with Myocardial infarction. Serum samples were subjected for assay of creatine kinase (CK:MB), Lactate dehydrogenase, troponin I, ADMA, Serum MDA level was determined.

RESULTS

Data obtained showed that serum CKMB, LDH1, AST, Troponin T and ADMA levels were significant elevated in MI with or without Thalassemia compared with control groups. Serum MDA was statistically significantly elevated in MI with or without Thalassemia compared with control groups. The serum level of troponin T showed an area under curve (AUC) of 0.92, (sensitivity 91.0 % and specificity, 88%). Also, the ADMA supported the diagnostic profile, showing an AUC of 0.85 with (sensitivity, 92.0%; specificity, 91,9%).

CONCLUSION

Serum ADMA is sensitive marker for incidence of MI in thalassemia patients.

Predicting factors for liver iron overload at the first magnetic resonance in children with thalassaemia major

BACKGROUND

Transfusion dependency determines iron overload in thalassaemia major, with devastating complications. Significant liver iron overload has been observed from early childhood and we aimed to evaluate factors that could predict liver iron overload at the first magnetic resonance imaging (MRI).

MATERIALS AND METHODS

All transfusion-dependent children who underwent MRI to assess iron overload were retrospectively studied. Age, weight, height, blood requirement, chelation drug and dosage, serum ferritin and liver enzymes were evaluated at three specific steps: start of transfusion regimen, start of chelation therapy, and first MRI.

RESULTS

Among 198 patients, 25 children met inclusion criteria. No differences were detected in all the assessed parameters at start of transfusion regimen and chelation therapy (p>0.05) between patients with good iron balance (liver iron concentration [LIC] <7 mg Fe/g dry weight [dw]) and liver iron overload (LIC >7). At the first MRI, patients with iron overload had significantly higher serum ferritin (3,080.3±1,078.5 vs 1,672.0±705.3 ng/mL; p<0.01) while patients with good iron control maintained a stable ferritin value from the start of chelation therapy but showed significantly lower height Z-score (-1.48±1.02 vs -0.36±1.55; p=0.04). Serum ferritin >1,770 ng/mL was detected as the best threshold for predicting liver iron overload at the first MRI (p=0.0003).

CONCLUSION

In order to prevent liver iron overload at the first MRI, children should maintain a stable level of serum ferritin below 1,770 from the start of chelation therapy. However, strict monitoring of growth is mandatory.

Assessment of liver and cardiac iron overload using MRI in patients with chronic anemias in Latin American countries: results from ASIMILA study

OBJECTIVES

A multicenter, noninterventional, observational study was conducted in the Latin American countries including Argentina, Brazil, Colombia, Mexico, and Venezuela to assess the prevalence of liver and cardiac iron overload using magnetic resonance imaging (MRI) in patients with chronic anemias except thalassemia.

METHODS

Patients aged >10 years with transfusion-dependent anemias, except thalassemia, either with <20 units of red blood cell (RBC) transfusions with serum ferritin (SF) levels >2000 ng/mL or with ≥20 units of RBC transfusions regardless of SF level in their lifetime, were enrolled. Iron overload was assessed using MRI.

RESULTS

Among 175 patients included, the majority had sickle cell disease (SCD; 52%), followed by aplastic anemia (AA; 17.7%), myelodysplastic syndrome (MDS; 8.6%), Diamond-Blackfan anemia (DBA; 4%), pure red cell aplasia (1.1%), and others (16.6%). Liver iron overload was observed in 76.4% of patients, while cardiac iron overload was seen in 19.2% when assessed by MRI. The prevalence of iron overload was 80.2% in patients with SCD, 73.3% in MDS, 77.4% in AA, 100% in pure red cell aplasia, 71.4% in DBA, and 68.9% in other transfusion-related disorders. A moderate correlation between liver iron concentration (LIC) and SF was observed in patients with SCD and MDS (r = 0.47 and r = 0.61, respectively). All adverse events reported were consistent with the published data for deferasirox or underlying disease.

CONCLUSION

A high prevalence of iron overload in this patient population in Latin American countries indicates that a better diagnosis and management of iron overload is required in these countries.

Magnetic resonance imaging during management of patients with transfusion-dependent thalassemia: a single-center experience

BACKGROUND

Cardiac and hepatic magnetic resonance imaging evaluation during treatment can tailor physicians' chelation therapy titrations.

AIM

The aim of the study was to assess the relationship of cardiac and hepatic T2* values with chelation therapy in patients with transfusion-dependent thalassemia (TDT).

METHODS

A total of 106 patients with TDT who were followed up in Istanbul Medical Faculty Thalassemia Center were evaluated for the study. Forty-eight (45%) patients with TDT had more than one consecutive MRI examination. The patients were divided into three subgroups according to the cardiac T2* values as the high-risk group (T2* MRI < 10 ms), medium-risk group (T2* MRI 10-20 ms), and the low-risk group (T2* MRI > 20 ms).

RESULTS

The majority of patients used DFX (deferasirox) (79%) and deferiprone (DFP) (17%). Approximately 80% of patients according to cardiac T2* value and 40% of patients according to hepatic T2* value were initially in the low-risk group. Patients with follow-up MRI examinations exhibited significant improvement in liver iron concentration, which correlated with an increase in hepatic T2* values. The decrease of liver iron concentration was prominent in the DFX group (p < 0.01). The serum ferritin level was significantly correlated with liver iron concentrations (rs = 0.65, p < 0.001), hepatic T2* value (rs = - 0.62, p < 0.001), but not with cardiac T2* value (rs = - 0.20, p = 0.07).

CONCLUSION

Cardiovascular and hepatic MRI is a useful follow-up tool during the assessment of risk groups and chelation therapy of patients with TDT. Consecutive MRI tests showed good monitoring of cardiac and liver iron overload.

The frequency of hypothyroidism and its relationship with HCV positivity in patients with thalassemia major in southern Iran

INTRODUCTION

Hypothyroidism is one the most complication due to iron overload in patients with β-thalassemia major (TM). On the other hand these patients are prone to Hepatitis C virus (HCV) infection that can cause  thyroid dysfunction by itself or as the side effect of treatment with interferon (INF) or IFN plus ribavirin. The aim of this study is to evaluate the association of hypothyroidism with HCV positivity and serum ferritin levels in patients with TM.

METHODS

In this cross-sectional study, 201 randomly selected patients with TM who were registered at the Thalassemia Clinic of a tertiary hospital in Shiraz, southern Iran were investigated. Thyroid function tests and serologic screening assays for HCV seropositivity (HCV Ab and HCV-RNA) were conducted for all patients.

RESULTS

Frequency of hypothyroidism was 22.9% including 19.9% subclinical hypothyroidism, 2% primary overt hypothyroidism and 1% central hypothyroidism. Eighty six patients (42.8%) were HCV Ab positive and 60 patients (29.9%) were HCV RNA positive. No significant relationship was found between hypothyroidism and HCV positivity or receiving IFN-α (P>0.05). Hypothyroidism showed a borderline significant association with high serum ferritin levels in TM patients (P=0.055).

CONCLUSION

Our results showed no significant association between hypothyroidism and HCV infection in TM patients. It seems that the main mechanism of hypothyroidism in our patients is iron overload; however, for better evaluation a larger multicenter study is recommended.  Also due to the importance of consequences of HCV infection, more careful pre-transfusional screening of blood should be considered in TM patients.

The Correlation of Cardiac and Hepatic Hemosiderosis as Measured by T2*MRI Technique with Ferritin Levels and Hemochromatosis Gene Mutations in Iranian Patients with Beta Thalassemia Major

Objectives

Organ-specific hemosiderosis and iron overload complications are more serious and more frequent in some patients with beta thalassemia major (BTM) compared with others. We investigated whether coinheritance of HFE H63D or C282Y gene mutations in patients with BTM contributes to the phenotypic variation of iron overload complications and assessed the correlation of cardiac and hepatic hemosiderosis with plasma ferritin levels.

Methods

We studied 60 patients with BTM with a mean age of 17.5±9.1 years from the Northwest of Iran. HFE gene mutations were analyzed using the polymerase chain reaction-restriction fragment length polymorphism method. Cardiac and hepatic hemosiderosis was assessed using T2*magnetic resonance imaging (MRI). Ferritin levels were measured using the enzyme immunoassay method.

Results

Ferritin levels showed a strong inverse correlation with hepatic T2*MRI values (r = -0.631, p = 0.001) but a poor correlation with cardiac T2*MRI values (r = -0.297, p = 0.044). The correlation between cardiac T2*MRI values and hepatic T2*MRI values was poor and insignificant (r = 0.287, p = 0.058). Genotype and allele distribution of HFE H63D and C282Y mutation did not differ significantly between patients with and without hepatic or cardiac hemosiderosis (p > 0.050). However, carriers of HFE 63D allele had significantly higher ferritin levels compared with non-carriers (1 903±993 vs. 992±683, p < 0.001).

Conclusions

Cardiac T2*MRI values showed a poor correlation with hepatic T2*MRI values and ferritin levels. Accurate assessment of cardiac iron overload in patients with BTM can only be done using the T2*MRI technique. Additionally, HFE H63D is a significant determinant factor for elevated ferritin levels in BTM patients.

Thalassaemia

Inherited haemoglobin disorders, including thalassaemia and sickle-cell disease, are the most common monogenic diseases worldwide. Several clinical forms of α-thalassaemia and β-thalassaemia, including the co-inheritance of β-thalassaemia with haemoglobin E resulting in haemoglobin E/β-thalassaemia, have been described. The disease hallmarks include imbalance in the α/β-globin chain ratio, ineffective erythropoiesis, chronic haemolytic anaemia, compensatory haemopoietic expansion, hypercoagulability, and increased intestinal iron absorption. The complications of iron overload, arising from transfusions that represent the basis of disease management in most patients with severe thalassaemia, might further complicate the clinical phenotype. These pathophysiological mechanisms lead to an array of clinical manifestations involving numerous organ systems. Conventional management primarily relies on transfusion and iron-chelation therapy, as well as splenectomy in specific cases. An increased understanding of the molecular and pathogenic factors that govern the disease process have suggested routes for the development of new therapeutic approaches that address the underlying chain imbalance, ineffective erythropoiesis, and iron dysregulation, with several agents being evaluated in preclinical models and clinical trials.

Prevalence of low bone mass among adolescents with nontransfusion-dependent hemoglobin E/β-thalassemia and its relationship with anemia severity

BACKGROUND

Low bone mass is common among adolescents with transfusion-dependent β-thalassemia despite adequate transfusion and iron chelation. However, there are few reports regarding bone mineral density (BMD) among adolescents with nontransfusion-dependent thalassemia (NTDT). Indeed, only BMD data in patients with nontransfusion-dependent (NTD) β-thalassemia intermedia have been reported. No previous study has investigated BMD among adolescents with NTD hemoglobin (Hb) E/β-thalassemia.

OBJECTIVE

To determine the prevalence of low bone mass among adolescents with NTD Hb E/β-thalassemia and factors relating to low bone mass.

METHODS

We investigated BMD of lumbar spine (L2-L4; BMDLS) and total body (BMDTB), as measured by dual-energy X-ray absorptiometry, in 22 adolescents (aged 13.2-20 years) with NTD Hb E/β-thalassemia.

RESULTS

Low bone mass was found to be 18.2% and 22.7% at the lumbar spine (BMDLS Z-score adjusted for bone age and height age) and 13.6% and 9.1% at the total body (BMDTB Z-score adjusted for bone age and height age). Patients with mean Hb level <8 g/dl were more likely to have low bone mass (BMDLS and BMDTB Z-scores adjusted for bone age) compared to those with Hb level ≥ 8 g/dl. Mean Hb level correlated with BMDLS and BMDTB Z-scores adjusted for bone age.

CONCLUSION

We demonstrated that a low Hb level was associated with low bone mass among adolescents with NTD Hb E/β-thalassemia. A significant proportion of low bone mass among these patients highlights the importance of appropriate management, including red cell transfusion, vitamin D and calcium supplementation for improved long-term bone health.

Growth hormone therapy for people with thalassaemia

BACKGROUND

Thalassaemia is a recessively-inherited blood disorder that leads to anaemia of varying severity. In those affected by the more severe forms, regular blood transfusions are required which may lead to iron overload. Accumulated iron from blood transfusions may be deposited in vital organs including the heart, liver and endocrine organs such as the pituitary glands which can affect growth hormone production. Growth hormone deficiency is one of the factors that can lead to short stature, a common complication in people with thalassaemia. Growth hormone replacement therapy has been used in children with thalassaemia who have short stature and growth hormone deficiency.

OBJECTIVES

To assess the benefits and safety of growth hormone therapy in people with thalassaemia.

SEARCH METHODS

We searched the Cochrane Haemoglobinopathies Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles, reviews and clinical trial registries. Our database and trial registry searches are current to 10 August 2017 and 08 August 2017, respectively.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials comparing the use of growth hormone therapy to placebo or standard care in people with thalassaemia of any type or severity.

DATA COLLECTION AND ANALYSIS

Two authors independently selected trials for inclusion. Data extraction and assessment of risk of bias were also conducted independently by two authors. The quality of the evidence was assessed using GRADE criteria.

MAIN RESULTS

One parallel trial conducted in Turkey was included. The trial recruited 20 children with homozygous beta thalassaemia who had short stature; 10 children received growth hormone therapy administered subcutaneously on a daily basis at a dose of 0.7 IU/kg per week and 10 children received standard care. The overall risk of bias in this trial was low except for the selection criteria and attrition bias which were unclear. The quality of the evidence for all major outcomes was moderate, the main concern was imprecision of the estimates due to the small sample size leading to wide confidence intervals. Final height (cm) (the review's pre-specified primary outcome) and change in height were not assessed in the included trial. The trial reported no clear difference between groups in height standard deviation (SD) score after one year, mean difference (MD) -0.09 (95% confidence interval (CI) -0.33 to 0.15 (moderate quality evidence). However, modest improvements appeared to be observed in the following key outcomes in children receiving growth hormone therapy compared to control (moderate quality evidence): change between baseline and final visit in height SD score, MD 0.26 (95% CI 0.13 to 0.39); height velocity, MD 2.28 cm/year (95% CI 1.76 to 2.80); height velocity SD score, MD 3.31 (95% CI 2.43 to 4.19); and change in height velocity SD score between baseline and final visit, MD 3.41 (95% CI 2.45 to 4.37). No adverse effects of treatment were reported in either group; however, while there was no clear difference between groups in the oral glucose tolerance test at one year, fasting blood glucose was significantly higher in the growth hormone therapy group compared to control, although both results were still within the normal range, MD 6.67 mg/dL (95% CI 2.66 to 10.68). There were no data beyond the one-year trial period.

AUTHORS' CONCLUSIONS

A small single trial contributed evidence of moderate quality that the use of growth hormone for a year may improve height velocity of children with thalassaemia although height SD score in the treatment group was similar to the control group. There are no randomised controlled trials in adults or trials that address the use of growth hormone therapy over a longer period and assess its effect on final height and quality of life. The optimal dosage of growth hormone and the ideal time to start this therapy remain uncertain. Large well-designed randomised controlled trials over a longer period with sufficient duration of follow up are needed.

Correlation of Pancreatic Iron Overload Measured by T2*-Weighted Magnetic Resonance Imaging in Diabetic Patients with β-Thalassemia Major

Diabetes mellitus (DM) is one of the potential complications in patients with transfusion-dependent β-thalassemia major (β-TM). In this case-controlled study, we examined the pancreatic iron levels in outpatients with β-TM. In this study, cases of patients with β-TM and DM were gender- and age-matched with control subjects, who were non-diabetic and had normal blood glucose on standard oral glucose tolerance (OGTT) tests. One of four diagnoses [normal, pre-diabetes, impaired glucose tolerance (IGT), DM] was made according to the American Diabetes Association (ADA) criteria. The T2*-weighted magnetic resonance imaging (T2*-weighted MRI) of the heart, liver, and pancreas was performed using a 1.5 Tesla scanner. The study enrolled 26 diabetic cases, 17 non-diabetic cases, and eight cases of IGT or pre-diabetes cases. The severity of pancreatic and cardiac iron siderosis was significantly different between the groups. We found a statistically significant difference at 5.6 ms in the T2*-weighted MRI values for the pancreas between patients with normal vs. abnormal glucose metabolism [p < 0.009; odds ratio (OR): 11.2; 95% confidence interval (95% CI): 1.32-94.4)]. The receiver operating characteristic (ROC) curve for the 5.6 ms cutoff led to an area under the curve (AUC) of 0.69 (95% CI: 55.0-84.0; p < 0.02), with sensitivity and specificity of 94.0 and 42.0%, respectively. There was a moderate positive correlation between pancreatic and cardiac T2*-weighted MRI (r = 0.4; p < 0.001), and a weak correlation between the pancreas and the liver (r = 0.38; p < 0.005). To conclude, we have introduced a cutoff of 5.6 ms on T2*-weighted MRI of the pancreas for prediction of abnormal glucose metabolism in β-TM patients.

The Impact of Iron Overload in Acute Leukemia: Chronic Inflammation, But Not the Presence of Nontransferrin Bound Iron is a Determinant of Oxidative Stress

In the literature, studies on the oxidant effects of nontransferrin bound iron [NTBI (eLPI assay)] during chemotherapy of acute lymphoblastic leukemia and acute myeloblastic leukemia are lacking. We established NTBI and oxidative stress determinants (OSD), iron parameters, high-sensitive C-reactive protein (hs-CRP) levels, liver tests, cumulative chemotherapeutic doses, and transfused blood in 36 children with acute leukemia throughout chemotherapy. These parameters were determined at the beginning and end of chemotherapy blocks (11 time points) and in 20 healthy children using enzyme-linked immunosorbent assay, and colorimetric and fluorometric enzymatic methods. In acute lymphoblastic leukemia, NTBI, OSD, and hs-CRP were higher than controls at 4/11, 7/11, and 9/11 time points (P<0.05). At 3 time points, NTBI and OSD concurrently increased. Ferritin, soluble transferrin receptor, serum iron, and transferrin saturation were higher than in controls at 5 to 11/11 time points (P<0.05). Those with NTBI had higher iron parameters than those without NTBI (P<0.05), but showed similar OSD, hs-CRP, liver enzymes, cumulative chemotherapeutics, and transfused blood (P>0.05). OSD did not correlate with NTBI, but correlated with hs-CRP. In conclusion, NTBI is a poor predictor of OSD in acute leukemia possibly because of the heterogeneity of NTBI and chronic inflammation. Further studies are needed to delineate the pathophysiology of these diseases.

Heart Rate Recovery as a Novel Test for Predicting Cardiac Involvement in Beta-Thalassemia Major

BACKGROUND

Abnormal heart rate recovery (HRR) is predictive of cardiac mortality. Autonomic abnormalities in beta-thalassemia major (TM) patients have been reported in previous studies. However, the importance of low HRR in exercise stress test in TM patients has not yet been ascertained. Therefore, this study will be the first of its kind in the literature.

METHODS

Exercise stress test was performed on 56 TM patients who were being treated at the Thalassemia Center of our hospital, along with 46 non-TM iron deficiency anemia (IDA) patients as a control group. Values for HHR were recorded at 1, 2, 3, 4 and 5 min, and HRR was calculated by the difference of heart rate at peak exercise and at a specific time interval following the onset of recovery.

RESULTS

All HRR values were found to be lower in TM patients compared to those in the IDA group. Exercise capacity [metabolic equivalents (METs)] was also found to be low in these patients (p < 0.001) as well. Total exercise time was significantly lower in the TM group compared to the IDA group (8.40 ± 1.7 min vs. 11.17 ± 1.51 min, p < 0.001). Exercise capacity (METs) was also lower in the TM group compared to the IDA group. Mean T2* value was 28.3 ± 13.7 ms in TM patients on magnetic resonance imaging (MRI). In addition, there are 18 TM patients with T2* value was < 20 ms.

CONCLUSIONS

This study found that TM was independently associated with low HRR. Such a condition is an indicator of autonomic dysfunction in TM patients, since abnormal HRR is related to impaired autonomic response. In addition, impaired HRR may be a marker of early cardiac involvement in patients, whose T2* value is high on MRI. Modifying HRR with a cardiac rehabilitation program in TM patients with impaired HRR is a field open for further investigation.

How we manage iron overload in sickle cell patients

Blood transfusion plays a prominent role in the management of patients with sickle cell disease (SCD), but causes significant iron overload. As transfusions are used to treat the severe complications of SCD, it remains difficult to distinguish whether organ damage is a consequence of iron overload or is due to the complications treated by transfusion. Better management has resulted in increased survival, but prolonged exposure to iron puts SCD patients at greater risk for iron-related complications that should be treated. The success of chelation therapy is dominated by patient adherence to prescribed treatment; thus, adjustment of drug regimens to increase adherence to treatment is critical. This review will discuss the current biology of iron homeostasis in patients with SCD and how this informs our clinical approach to treatment. We will present the clinical approach to treatment of iron overload at our centre using serial assessment of organ iron by magnetic resonance imaging.

Magnetic resonance imaging for characterizing myocardial diseases

The National Institute of Health defined cardiomyopathy as diseases of the heart muscle. These myocardial diseases have different etiology, structure and treatment. This review highlights the key imaging features of different myocardial diseases. It provides information on myocardial structure/orientation, perfusion, function and viability in diseases related to cardiomyopathy. The standard cardiac magnetic resonance imaging (MRI) sequences can reveal insight on left ventricular (LV) mass, volumes and regional contractile function in all types of cardiomyopathy diseases. Contrast enhanced MRI sequences allow visualization of different infarct patterns and sizes. Enhancement of myocardial inflammation and infarct (location, transmurality and pattern) on contrast enhanced MRI have been used to highlight the key differences in myocardial diseases, predict recovery of function and healing. The common feature in many forms of cardiomyopathy is the presence of diffuse-fibrosis. Currently, imaging sequences generating the most interest in cardiomyopathy include myocardial strain analysis, tissue mapping (T₁, T_2, T₂*) and extracellular volume (ECV) estimation techniques. MRI sequences have the potential to decode the etiology by showing various patterns of infarct and diffuse fibrosis in myocarditis, amyloidosis, sarcoidosis, hypertrophic cardiomyopathy due to aortic stenosis, restrictive cardiomyopathy, arrythmogenic right ventricular dysplasia and hypertension. Integrated PET/MRI system may add in the future more information for the diagnosis and progression of cardiomyopathy diseases. With the promise of high spatial/temporal resolution and 3D coverage, MRI will be an indispensible tool in diagnosis and monitoring the benefits of new therapies designed to treat myocardial diseases.

R2*-relaxometry of the pancreas in patients with human hemochromatosis protein associated hereditary hemochromatosis

PURPOSE

To evaluate pancreatic iron in patients with human hemochromatosis protein associated hereditary hemochromatosis (HHC) using R2* relaxometry.

MATERIALS AND METHODS

81 patients (58 male, 23 female; median age 49.5, range 10-81 years) with HHC were retrospectively studied. All underwent 1.5T magnetic resonance imaging (MRI) of the abdomen. A fat-saturated multi-gradient echo sequence with 12 echoes (TR=200ms; TE-initial 0.99ms; Delta-TE 1.41ms; 12 echoes; flip-angle: 20°) was used for the R2* quantification of the liver and the pancreas. Parameter maps were analyzed using regions of interest (3 in the liver and 2 in the pancreas) and R2* values were correlated.

RESULTS

59/81 patients had a liver R2*≥70 1/s of which 10/59 patients had a pancreas R2*≥50 1/s. No patient presented with a liver R2*<70 1/s and pancreas R2*≥50 1/s. All patients with pancreas R2* values≥50 1/s had liver R2* values≥70 1/s. ROC analysis resulted in a threshold of 209.4 1/s for liver R2* values to identify HFE positive patients with pancreas R2* values≥50 1/s with a median specificity of 78.87% and a median sensitivity of 90%.

CONCLUSION

In patients with HHC R2* relaxometry of the pancreas should be performed when liver iron overload is present and can be omitted in cases with no sign of hepatic iron.

The Ferritin Superfamily

Iron is very important in many biological processes and the ferritin protein family has evolved to store iron and to maintain cellular iron homeostasis. The deletion of the coding gene for the H subunit of ferritin leads to early embryonic death in mice and mutations in the gene for the L subunits in humans has been observed in neurodegenerative diseases, such as neuroferritinopathy. Thus, understanding how ferritin works is imperative and many studies have been conducted to delineate the molecular mechanism of ferritins and bacterioferritins. In the ferritin protein family, it is clear that a catalytic center for iron oxidation, the routes for iron to reach this center and the ability to nucleate an iron core, are common requirements for all ferritins. However, there are differences in the structural and mechanistic details of iron oxidation and mineralization. Although a common mechanism has been proposed for all ferritins, this mechanism needs to be further explored. There is a mechanistic diversity related to structural variation in the ferritin protein family. It is clear that other factors appear to affect the mechanism of iron oxidation and mineralization. This review focusses on the structural features of the ferritin protein family and its role in the mechanism of iron mineralization.

Optimizing the diagnosis and the treatment of iron overload diseases

A number of human disorders are related to chronic iron overload, either of genetic or acquired origin. The multi-organ damage produced by iron excess leads, in adults and in children, to severe clinical consequences, affecting both quality of life and life expectancy. The diagnosis is increasingly based on a non-invasive strategy, resorting to clinical, biological and imaging data. The treatment rests on either venesection or chelation therapy, depending on the etiology. Major advances in the fields of molecular biology, pharmacology, and biotechnology pave the road for key improvements in the diagnostic and therapeutic management of the patients.

Heart Rate Variability for Early Detection of Cardiac Iron Deposition in Patients with Transfusion-Dependent Thalassemia

Background

Iron overload cardiomyopathy remains the major cause of death in patients with transfusion-dependent thalassemia. Cardiac T2* magnetic resonance imaging is costly yet effective in detecting cardiac iron accumulation in the heart. Heart rate variability (HRV) has been used to evaluate cardiac autonomic function and is depressed in cases of thalassemia. We evaluated whether HRV could be used as an indicator for early identification of cardiac iron deposition.

Methods

One hundred and one patients with transfusion-dependent thalassemia were enrolled in this study. The correlation between recorded HRV and hemoglobin, non-transferrin bound iron (NTBI), serum ferritin and cardiac T2* were evaluated.

Results

The median age was 18 years (range 8–59 years). The patient group with a 5-year mean serum ferritin >5,000 ng/mL included significantly more homozygous β-thalassemia and splenectomized patients, had lower hemoglobin levels, and had more cardiac iron deposit than all other groups. Anemia strongly influenced all domains of HRV. After adjusting for anemia, neither serum ferritin nor NTBI impacted the HRV. However cardiac T2* was an independent predictor of HRV, even after adjusting for anemia. For receiver operative characteristic (ROC) curve analysis of cardiac T2* ≤20 ms, only mean ferritin in the last 12 months and the average of the standard deviation of all R-R intervals for all five-minute segments in the 24-hour recording were predictors for cardiac T2* ≤20 ms, with area under the ROC curve of 0.961 (p<0.0001) and 0.701 (p = 0.05), respectively.

Conclusions

Hemoglobin and cardiac T2* as significant predictors for HRV indicate that anemia and cardiac iron deposition result in cardiac autonomic imbalance. The mean ferritin in the last 12 months could be useful as the best indicator for further evaluation of cardiac risk. The ability of serum ferritin to predict cardiac risk is stronger than observed in other thalassemia cohorts. HRV might be a stronger predictor of cardiac iron in study populations with lower somatic iron burdens and greater prevalence of cardiac iron deposition.

Imaging and quantification of iron-oxide nanoparticles (IONP) using MP-RAGE and UTE based sequences

PURPOSE

To investigate two-dimensional (2D) and three-dimensional (3D) ultrashort echo time (UTE) and 3D magnetization-prepared rapid gradient-echo (MP-RAGE) sequences for the imaging of iron-oxide nanoparticles (IONP).

METHODS

The phantoms were composed of tubes filled with different IONP concentrations ranging from 2 to 45 mM. The tubes were fixed in an agarose gel phantom (0.9% by weight). Morphological imaging was performed with 3D MP-RAGE, 2D UTE, 2D adiabatic inversion recovery-prepared UTE (2D IR-UTE), 3D UTE with Cones trajectory (3D Cones), and 3D IR-Cones sequences. Quantitative assessment of IONP concentration was performed using R2*(1/T2*) and R₁ (1/T₁ ) measurements using a 3 Tesla (T) scanner.

RESULTS

The 3D MP-RAGE sequence provides high-contrast images of IONP with concentration up to 7.5 mM. Higher IONP concentration up to 37.5 mM can be detected with the UTE sequences, with the highest IONP contrast provided by the 3D IR-Cones sequence. A linear relationship was observed between R2* and IONP concentration up to ∼45 mM, and between R₁ and IONP concentration up to ∼30 mM.

CONCLUSION

The clinical 3D MP-RAGE sequence can be used to assess lower IONP concentration up to 7.5 mM. The UTE sequences can be used to assess higher IONP concentration up to 45 mM. Magn Reson Med 78:226-232, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

Evaluation of the glucocorticoid, mineralocorticoid, and adrenal androgen secretion dynamics in a large cohort of patients aged 6-18 years with transfusion-dependent β-thalassemia major, with an emphasis on the impact of cardiac iron load

The variable presence of adrenal insufficiency (AI) due to hypocortisolemia (HC) in patients with thalassemia is well established; however, the prevalence of adrenocortical hypofunction (ACH) in the zona glomerulosa and zona reticularis of the adrenal cortex is unknown. To establish the prevalence of ACH, we examined the cortisol response to 1-µg and 250-µg ACTH tests, plasma aldosterone (A)/plasma renin activity (PRA) ratio, and serum dehydroepiandrosterone sulfate (DHEAS) levels in a large cohort of patients with thalassemia, and to investigate the impact of total body iron load (TBIL) on adrenocortical function. The setting used was University hospital and government-based tertiary care center. One hundred twenty-one (52 females) patients with β-thalassemia major (β-TM) and 72 healthy peers (38 females) were enrolled. The patients underwent a 250-µg cosyntropin test if their peak cortisol was <500 nmol/L in a 1-µg cosyntropin test. Magnetic resonance imaging (MRI) was performed to assess the MRI-based liver iron content and cardiac MRI T2* iron. The associations between ACH and TBIL were investigated. The patients with thalassemia had lower ACTH, cortisol, DHEAS, and A/PRA values compared with the controls (p < 0.001). Thirty-nine patients (32.2 %) had HC [primary (n = 1), central (n = 36), combined (n = 2)], and 47 (38.8 %) patients had reduced DHEAS levels; 29 (24.0 %) patients had reduced A/PRA ratios. Forty-six (38.0 %) patients had hypofunction in one of the adrenal zones, 26 (21.5 %) had hypofunction in two adrenal zones, and 9 (7.4 %) had hypofunction in all three zones. Patient age and TBIL surrogates were significant independent parameters associated with ACH. Cardiac MRI T2* iron was the only significant parameter that predicted the severity of ACH at a cut-off of 20.6 ms, with 81 % sensitivity and 78 % specificity. Patients with thalassemia have a high prevalence of AI due to HC and zona glomerulosa and zona reticularis hypofunction. TBIL surrogates can predict ACH, but cardiac iron was the only surrogate that was adequately sensitive to predict the severity of ACH.

Detection of Early Right Ventricular Dysfunction in Young Patients With Thalassemia Major Using Tissue Doppler Imaging

Background

Myocardial iron overload is the most common cause of mortality in patients with thalassemia major (TM), also known as beta-thalassemia. T2* cardiovascular magnetic resonance imaging (MRI) is the best way of monitoring cardiac iron, and new echocardiographic techniques can be used to assess cardiac function.

Objectives

The aim of this study was to assess the systolic and diastolic right ventricular (RV) function of patients with TM using tissue Doppler imaging (TDI) and to determine whether this echocardiographic technique is an adequate diagnostic tool for the screening and detection of subclinical cardiac dysfunction.

Patients and Methods

Eighty-four patients with TM were evaluated by conventional echocardiography and pulse-wave TDI. The data of the TM group (Group 1) were compared with that of 85 age- and sex-matched healthy controls (Group 2). Cardiovascular T2* MRI examinations were performed in 49 of the 85 patients.

Results

The patients with TM had significantly lower values for weight, height, body mass index, systolic arterial pressure, deceleration time, E’/A’, and ejection time (ET) than the controls. Group 1 also had significantly higher values for peak early diastolic velocity (E) over peak late diastolic velocity (A), peak early diastolic velocity of TDI (E’), peak late diastolic velocity of TDI (A’), E/E’, isovolumetric relaxation time, isovolumetric contraction time, and RV magnetic perfusion imaging (MPI) than Group 2.

Conclusions

RV diastolic dysfunction occurs before systolic deterioration in patients with TM and cannot be screened with conventional echocardiographic techniques. In routine practice, TDI measurements, MPI (for global function) and the E/E’ parameter (for diastolic function) can be used to screen and detect early RV dysfunction.