Preliminary Results of Full Body Iron Overload Measurement by a Magnetic Susceptometer.

Abstract Accurate assessment of body-iron accumulation is essential for managing therapy of iron-chelating diseases characterized by iron overload such as thalassemia, hereditary hemochromatosis, myelodysplasia and other forms of severe anemia. At present, the gold standard to determine liver-iron concentration (LIC) is liver needle biopsy. In this work, we present an alternative non-invasive technique to measure LIC based on a room-temperature susceptometer. SQUID biosusceptometers and MRI are currently the only validated non-invasive methods for LIC measurements. However, SQUIDs are liquid helium-cooled superconducting devices, therefore costly and resource intensive. Furthermore, SQUIDs are only sensitive to a fraction of the liver volume because of their magnetic configuration. MRI requires large magnets with dedicated software and hardware, trained operators, and is accurate only at low iron concentration. The susceptometer presented herein measures iron overload in the whole liver, as the entire human torso fits within its region of sensitivity. Since all of its components operate at room temperature, this susceptometer is more affordable then competing techniques and can reach a wider hospital base. The study was approved by the local Ethics Committee and all subjects gave informed consent. Since February 2005, 40 patients (30 thalassemia major or intermedia, 5 hereditary hemochromatosis, 5 other severe anemia) and 68 healthy volunteers have been measured. The signal picked up by the susceptometer has two sources: an overall magnetic background of the torso and an eventual contribution from liver iron excess. After measuring the magnetic signature of a patient, statistical analysis methods and neural-network simulations (trained using the control data) are employed to estimate the background signal, given the patient anthropometric data. Liver-iron overload is then determined by subtraction of the estimated background from the total measured signal. The refinement of the methodology is in progress and, at present, the error in liver iron is about 1g (SD), corresponding to typical concentrations of 0.5 mg/cm^3. A correlation study between iron overload and blood serum-ferritin concentration in the patient population attained a correlation coefficient R~0.73. Comparison with measurements of LIC via SQUID susceptometry on a subset of 30 patients participating in the present study (carried out by Dr. A. Piga at Ospedale S. Anna, Torino, Italy) yields a correlation coefficient R~0.77. Four patients (3 thalassemia major, 1 hereditary hemochromatosis) under intensive iron depletive therapy have been measured at least twice; our estimate of liver iron reduction is compatible with the clinical data (R~0.76). Comparison with LIC measured via biopsy is in progress. All comparison were blinded. These preliminary results indicate that possible applications of this non-invasive, full-body susceptometer include monitoring the efficacy of the therapy as well as improving the diagnosis and care management of patients with iron overload. Figure Figure

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Consequences and management of iron overload in sickle cell disease

Hematology ◽

10.1182/asheducation-2013.1.447 ◽

2013 ◽

Vol 2013 (1) ◽

pp. 447-456 ◽

Cited By ~ 57

Author(s):

John Porter ◽

Maciej Garbowski

Keyword(s):

Sickle Cell Disease ◽

Blood Transfusion ◽

Iron Overload ◽

Sickle Cell ◽

Iron Concentration ◽

Thalassemia Major ◽

Iron Loading ◽

Cell Disease ◽

Liver Iron Concentration ◽

Liver Iron

Abstract The aims of this review are to highlight the mechanisms and consequences of iron distribution that are most relevant to transfused sickle cell disease (SCD) patients and to address the particular challenges in the monitoring and treatment of iron overload. In contrast to many inherited anemias, in SCD, iron overload does not occur without blood transfusion. The rate of iron loading in SCD depends on the blood transfusion regime: with simple hypertransfusion regimes, rates approximate to thalassemia major, but iron loading can be minimal with automated erythrocyte apheresis. The consequences of transfusional iron overload largely reflect the distribution of storage iron. In SCD, a lower proportion of transfused iron distributes extrahepatically and occurs later than in thalassemia major, so complications of iron overload to the heart and endocrine system are less common. We discuss the mechanisms by which these differences may be mediated. Treatment with iron chelation and monitoring of transfusional iron overload in SCD aim principally at controlling liver iron, thereby reducing the risk of cirrhosis and hepatocellular carcinoma. Monitoring of liver iron concentration pretreatment and in response to chelation can be estimated using serum ferritin, but noninvasive measurement of liver iron concentration using validated and widely available MRI techniques reduces the risk of under- or overtreatment. The optimal use of chelation regimes to achieve these goals is described.

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Liver Fibrosis in Adult Thalassemia Patients Assessed by Transient Elastography.

Blood ◽

10.1182/blood.v110.11.3820.3820 ◽

2007 ◽

Vol 110 (11) ◽

pp. 3820-3820

Author(s):

Elena Cassinerio ◽

Mirella Fraquelli ◽

Elisabetta Volpato ◽

Cristina Rigamonti ◽

Massimo Colombo ◽

...

Keyword(s):

Iron Overload ◽

Transient Elastography ◽

Thalassemia Major ◽

Hcv Rna ◽

Liver Iron ◽

Non Invasive ◽

Group I ◽

Group Ii ◽

T2 Mri ◽

Severe Fibrosis

Abstract Background and aim. Transient elastography (TE) is a new, non-invasive and reproducible technique that measures liver stiffness (LSM). It has been demonstrated to be a reliable tool for assessing hepatic fibrosis and cirrhosis in patients with chronic liver disease (CLD). However, its role in patients with b- thalassemia has not been extensively investigated. The aim of the present study was to assess LSM and its possible correlation with iron overload in HCV positive patients with b- thalassemia major and intermedia. Methods. During a six-month period (from January to June 2007) 46 consecutive adults patients with b- thalassemia afferring to a single Italian Thalassemia Care Center in Milan, Italy, were enrolled in the study. Twenty-nine patients (Group I: 7 M and 23 F; mean age 31±SD 7.1 yrs; mean BMI 23.4±SD 3 Kg/m2) had b- thalassemia major and 17 intermedia (Group II: 10 M and 7 F; mean age 43±SD12.4 yrs; BMI 22 ±SD 3 Kg/m2). Sixteen patients (55%) in group I and two (12%) in group II were HCV RNA positive. All patients were examined by TE (FibroScan®; Echosens, Paris, France) and only the examinations with at least 10 validated measurements and a success rate of at least 60% were considered adequate. According to a previous study in CLD patients the considered TE cut off to diagnosing different stages of hepatic fibrosis were: >7.9 kPa for F≥2; >10.3 for ≥F3 and >11.9 for F=4. Twelve patients (all in group I) also had undergone liver biopsy. Necroinflammation and fibrosis were scored by METAVIR classification; liver iron concentration (LIC, mg/gr of liver dry weight) was measured on fresh tissue cores by atomic absorption spectrometry. Twenty-five patients underwent liver iron determination by T2* Magnetic Resonance Imaging (MRI) assessment. Results. In patients who underwent liver biopsy, LSM increased proportionally to the METAVIR stage and a significant positive correlation was observed between LSM and fibrosis stage (r=0.57, p= 0.039). Patients in group I had significantly higher values of mean LSM values (10.6± SD 9.3 kPa) and serum ferritin (SF) (1367±SD 1169 ng/mL) than those in group II (6.0± SD 3.3 kPa and 716±SD 472 ng/mL, respectively) (p<0.05). In both groups LSM did not significantly correlate with age, BMI, platelets count, serum iron and iron overload measured by T2* MRI. In group I a significant positive correlation was observed betweeen LSM and SF (r=0.47, p=0.008), ALT (r=0.87, p=0.0001) and GGT levels (r=0.80, p=0.0001). Among patients with b- thalassemia major LSM values did not differ significantly between HCV RNA positive (13.0±SD 12.5 kPa) and negative patients (7.7±SD 3.3 kPa) (p=NS) as well as the proportion of patients with significant (F>=2) or severe fibrosis (F>=3) did not differ significantly according to HCV viremic status. Conclusion TE is a reliable non invasive technique to stage liver fibrosis in patients with b- thalassemia major. In these patients with concomitant HCV infection a significant or severe fibrosis was observed in about one third of the cases. Apart from fibrosis also serum necroinflammatory activity, GGT levels and SF levels may influence LSM values. The reliability of liver iron overload by T2* MRI evaluation remains still to be validated.

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Safety of Deferasirox (Exjade®) in Patients with Transfusion-Dependent Anemias and Iron Overload Who Achieve Serum Ferritin Levels <1000 Ng/Ml during Long-Term Treatment

Blood ◽

10.1182/blood.v112.11.5423.5423 ◽

2008 ◽

Vol 112 (11) ◽

pp. 5423-5423 ◽

Cited By ~ 3

Author(s):

John B Porter ◽

Antonio Piga ◽

Alan Cohen ◽

John M Ford ◽

Janet Bodner ◽

...

Keyword(s):

Clinical Trials ◽

Abdominal Pain ◽

Iron Overload ◽

Serum Ferritin ◽

Safety Profile ◽

Iron Concentration ◽

Thalassemia Major ◽

Liver Iron ◽

Long Term Treatment ◽

Baseline Characteristics

Abstract Background: Maintaining serum ferritin (SF) levels below 1000 ng/mL has been reported to predict longer survival and a reduced risk of complications (eg heart failure) in patients with thalassemia major. Experience with deferoxamine (Desferal®, DFO) has indicated that the toxicity of DFO may increase as SF levels decrease. A target SF value in the deferasirox clinical trials was not specified per protocol, but was determined by the individual investigators. This analysis evaluates the safety of deferasirox (Exjade®) in a cohort of adult and pediatric patients with transfusion-dependent anemias and iron overload from two large clinical trials (107 and 108) who were chelated to SF levels <1000 ng/mL. Methods: In core studies 107 and 108, frequently-transfused patients with chronic anemias ≥2 years old received deferasirox 5–30 mg/kg/day for 1 year. Eligible patients were then enrolled in 4-year extension trials, where initial dosing was based on the end of core study liver iron concentration; dose adjustments were based on SF levels. Patients eligible for this analysis had an initial SF ≥1000 ng/mL. Patients who achieved a SF level <1000 ng/mL on ≥2 consecutive visits, any time after starting deferasirox, were identified. The number of days when SF was <1000 ng/mL was calculated for each patient. AEs in these patients were calculated for the entire period on deferasirox, and for the period following the first SF measurement of <1000 ng/mL, irrespective of future SF levels. Results: 474 patients were included in this analysis: underlying anemias were β-thalassemia (n=379), myelodysplastic syndromes (n=43), Diamond-Blackfan anemia (n=30) and other anemias (n=22). Overall, 13.5% patients achieved SF<1000 ng/mL in year 1, 18.6% in year 2, 25.7% in year 3, 32.5% in year 4 and 36.7% by the time of this analysis. Therefore, overall 174 patients (36.7%) reached a SF level <1000 ng/mL on ≥2 consecutive visits, while in 300 patients SF levels remained ≥1000 ng/mL. The median period for a SF value <1000 ng/mL was 149 days [range 18–1726]. Patient demographics, baseline characteristics and safety profiles of the two groups throughout deferasirox treatment are shown in Table 1. At month 54, median SF levels in the <1000 and >1000 ng/mL groups were 872 and 2118 ng/mL, respectively. The incidence of drug-related AEs (gastrointestinal, renal and liver) did not appear to increase during the periods after SF levels first decreased below 1000 ng/mL (data not shown). Table 1. Demographics, baseline characteristics and safety profile of patients who achieved SF levels <1000 ng/mL and patients who did not Patients who achieved SF <1000 ng/mL Patients who did not achieve SF <1000 ng/mL *Investigator-assessed; SCr, serum creatinine; ULN, upper limit of normal; ALT, alanine aminotransferase n 174 300 Male:female 85:89 145:155 Mean age ± SD, years 23.8 ± 16.7 23.5 ± 18.2 <16, n (%) 65 (37.4) 123 (41.0) ≥16, n (%) 109 (62.6) 177 (59.0) Enrolled from study 107:108 120:54 175:125 Median exposure to deferasirox, months 56.3 45.2 Mean actual deferasirox dose, mg/kg/day 20.3 22.9 Median baseline SF, ng/mL 1791 2883 Drug-related AEs* (≥5% in either group), n (%) Nausea 26 (14.9) 38 (12.7) Diarrhea 17 (9.8) 42 (14.0) Vomiting 14 (8.0) 25 (8.3) Abdominal pain 12 (6.9) 32 (10.7) Upper abdominal pain 6 (3.4) 20 (6.7) Rash 9 (5.2) 16 (5.3) Audiological abnormalities 7 (4.0) 4 (1.3) Ophthalmological abnormalities 4 (2.3) 5 (1.7) Two consecutive SCr increases >33% above baseline and above ULN 26 (14.9) 36 (12.0) Increase in ALT >10×ULN on at least 1 visit 12 (6.9) 20 (6.7) Baseline levels elevated 6 (3.4) 16 (5.3) Conclusions: Over the core and extension phases of these clinical studies, the safety profile of patients achieving SF levels <1000 ng/mL was similar to that observed in patients who did not achieve SF levels <1000 ng/mL. There was also no apparent increase in AEs associated with a decrease in SF levels <1000 ng/mL. In particular, no increase in the proportion of patients with creatinine increases >33% above baseline and ULN or with ALTs >10×ULN were observed in these patients. These findings suggest that ironoverloaded patients can be safely chelated with deferasirox to low SF levels.

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Target TMPRSS6 Using Antisense Technology for the Treatment of Hereditary Hemochromatosis and β-Thalassemia

Blood ◽

10.1182/blood.v120.21.481.481 ◽

2012 ◽

Vol 120 (21) ◽

pp. 481-481 ◽

Cited By ~ 1

Author(s):

Shuling Guo ◽

Carla Casu ◽

Sara Gardenghi ◽

Sheri Booten ◽

Andy Watt ◽

...

Keyword(s):

Treatment Group ◽

Iron Overload ◽

Hereditary Hemochromatosis ◽

Iron Concentration ◽

Transferrin Saturation ◽

Control Group ◽

Mrna Levels ◽

Liver Iron ◽

Hepcidin Expression ◽

Antisense Technology

Abstract Abstract 481 Hepcidin, the master regulator of iron homeostasis, is a peptide that is mainly expressed and secreted by the liver. Low levels of hepcidin are associated with increased iron absorption. In conditions in which hepcidin is chronically repressed, such as hereditary hemochromatosis and b-thalassemia, patients suffer from iron overload and very severe pathophysiological sequelae associated with this condition. Hepcidin expression is regulated predominantly at the transcriptional level by multiple factors. TMPRSS6, a transmembrane serine protease mutated in iron-refractory, iron-deficient anemia, is a major suppressor of hepcidin expression. It has been demonstrated that hepcidin expression is significantly elevated in Tmprss6−/− mice and reduction of Tmprss6 expression in hereditary hemochromatosis (Hfe−/−) mice ameliorates the iron overload phenotype (Finberg et al. Nature Genetics, 2008; Du et al. Science 2008; Folgueras et al. Blood 2008; Finberg et al., Blood, 2011). It has also been demonstrated that hepcidin up-regulation using either a hepcidin transgene or Tmprss6−/− significantly improves iron overload and anemia in a mouse model of β-thalassemia intermedia (th3/+ mice) (Gardenghi et al. JCI, 120:4466, 2010; Nai et al. Blood, 119: 5021, 2012). In this report, we have examined whether reduction of Tmprss6 expression using antisense technology is an effective approach for the treatment of hereditary hemochromatosis and β-thalassemia. Second generation antisense oligonucleotides (ASOs) targeting mouse Tmprss6 were identified. When normal male C57BL/6 mice were treated with 25, 50 and 100mg/kg/week ASO for four weeks, we achieved up to >90% reduction of liver Tmprss6 mRNA levels and up to 5-fold induction of hepcidin mRNA levels in a dose-dependent manner. Dose-dependent reductions of serum iron and transferrin saturation were also observed. ASOs were well tolerated in these animals. In Hfe−/− mice (both males and females), ASOs were administrated at 100 mg/kg for six weeks. This treatment normalized transferrin saturation (from 92% in control animals to 26% in treatment group) and significantly reduced serum iron (from >300ug/dl in control group to <150ug/dl in treatment group), as well as liver iron accumulation. Histopathological evaluation and Prussian's Perl Blue staining indicated that iron was sequestered by macrophages, which led to an increase in spleen iron concentration. The mouse model of thalassemia intermedia that we utilized mimics a condition defined as non-transfusion dependent thalassemia (NTDT) in humans. These patients exhibit increased iron absorption and iron overload due to ineffective erythropoiesis and suppression of hepcidin; iron overload is the most frequent cause of morbidity and mortality. Th3/+ animals exhibit ineffective erythropoiesis, characterized by increased proliferation and decreased differentiation of the erythroid progenitors, apoptosis of erythroblasts due to the presence of toxic hemichromes, reticulocytosis and shorter lifespan of red cells in circulation, leading to splenomegaly, extramedullary hematopoiesis and anemia (∼ 8 g/dL; Libani et al, Blood 112(3):875–85, 2008). Five month old th3/+ mice (both males and females) were treated with Tmprss6 ASO for six weeks. In th3/+ mice, ∼85% Tmprss6 reduction led to dramatic reductions of serum transferrin saturation (from 55–63% in control group down to 20–26% in treatment group). Liver iron concentration (LIC) was also greatly reduced (40–50%). Moreover, anemia endpoints were significantly improved with ASO treatment, including increases in red blood cells (∼30–40%), hemoglobin (∼2 g/dl), and hematocrit (∼20%); reduction of splenomegaly (∼50%); decrease of serum erythropoietin levels (∼50%); improved erythroid maturation as indicated by a strong reduction in reticulocyte number (50–70%) and in a normalized proportion between the pool of erythroblasts and enucleated erythroid cells. Hemichrome analysis showed a significant decrease in the formation of toxic alpha-globin/heme aggregates associated with the red cell membrane. This was consistent with a remarkable improvement of the red cell distribution width (RDW) as well as morphology of the erythrocytes. In conclusion, these data demonstrate that targeting TMPRSS6 using antisense technology is a promising novel therapy for the treatment of hereditary hemochromatosis and β-thalassemia. Disclosures: Guo: Isis Pharmaceuticals: Employment. Booten:Isis Pharmaceuticals: Employment. Watt:Isis Pharmaceuticals: Employment. Freier:Isis Pharmaceuticals: Employment. Rivella:Novartis Pharmaceuticals: Consultancy; Biomarin: Consultancy; Merganser Biotech: Consultancy, Equity Ownership, Research Funding; Isis Pharma: Consultancy, Research Funding. Monia:Isis Pharmaceuticals: Employment.

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Discrepancy between Serum Ferritin and Liver Iron Concentration in a Patient with Hereditary Hemochromatosis – The Value of T2* MRI

Case Reports in Oncology ◽

10.1159/000507756 ◽

2020 ◽

Vol 13 (2) ◽

pp. 712-715

Author(s):

Mustafa A. Al-Tikrity ◽

Mohamed A. Yassin

Keyword(s):

Iron Overload ◽

Serum Ferritin ◽

Ferritin Level ◽

Hereditary Hemochromatosis ◽

Iron Concentration ◽

Hfe Gene ◽

Liver Iron Concentration ◽

C282y Mutation ◽

Liver Iron ◽

T2 Mri

Primary hemochromatosis is an inherited disorder, and the homeostatic iron regulator (HFE) gene C282Y mutation is a common cause of hemochromatosis in Europe. We are reporting a case of a 56-year-old female known to have hemochromatosis with the HFE gene C282Y mutation with a serum ferritin level of 482 μg/L who underwent heart and liver T2* MRI which showed no evidence of iron overload – neither in the heart nor in the liver. This indicates that there is a discrepancy between serum ferritin and liver iron concentration by MRI and the superiority of T2* MRI in diagnosis and follow-up of iron overload in patients with hereditary hemochromatosis.

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Whole Liver Iron Overload Measurement by Magnetic Iron Detector (MID). A Non Cryogenic Bio-Susceptometer.

Blood ◽

10.1182/blood.v108.11.1547.1547 ◽

2006 ◽

Vol 108 (11) ◽

pp. 1547-1547

Author(s):

Mauro Marinelli ◽

Piergiorgio Beruto ◽

Barbara Gianesin ◽

Antonella Lavagetto ◽

Martina Lamagna ◽

...

Keyword(s):

Iron Overload ◽

Iron Reduction ◽

Hereditary Hemochromatosis ◽

Iron Concentration ◽

Large Error ◽

Liver Iron ◽

Heterogeneous Distribution ◽

Ferritin Concentration ◽

Liver Iron Overload ◽

Liver Needle Biopsy

Abstract Accurate assessment of body-iron accumulation is essential for diagnosis and therapy of iron-overload in diseases such as thalassemia, hereditary hemochromatosis and other forms of severe congenital or acquired anemias. At present, the gold standard to determine liver-iron concentration (LIC) is the invasive liver needle biopsy. This technique might lead to large error, in assessing iron burden, due to the heterogeneous distribution of iron deposition in the liver. SQUID bio-susceptometer and MRI are currently the only non-invasive validated methods for LIC measurements. The susceptometer presented herein, named Magnetic Iron Detector (MID), measures directly the iron overload in the whole liver. All of its components operate at room temperature. Since February 2005 about 150 patients and 90 healthy volunteers have been measured and the measures were obtained in blind. The local Ethics Committee approved the study and all subjects gave informed consent. The result of correlations with the LIC measurements by SQUID susceptometry (Dr. A. Piga, Turin) in 43 patients showed a R 0.86 (Fig 1). In 2 patients, affected by Congenital Hemocromatosis, we correlated the LIC measurement by MID with the assessment of the expected iron depletion obtained with the phlebotomy therapy R 0.94 (Fig 2). All the measurements were correlated with the serum-ferritin concentration values R 0.72. We obtained correlation with the LIC measurement by liver biopsy in 7 patients R 0.89, further measures are in progress. The reproducibility of the iron overload of the same patients, measured after a relatively short lapse of time, is better than 0.5g. In conclusion the data obtained shows that MID is a reliable instrument for the diagnosis of the liver iron overload and for the follow-up of the chelation therapy. It is simpler to operate being manageable directly in the Clinical Center and more affordable than competing techniques. Fig. 1 LIC measured by MID vs LIC measured by SQUID Fig. 1. LIC measured by MID vs LIC measured by SQUID Fig. 2 The iron reduction of two hemochromatosis patients, under phebotomy therapy, compare with the reduction measured by the MID. Fig. 2. The iron reduction of two hemochromatosis patients, under phebotomy therapy, compare with the reduction measured by the MID.

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Heightened Sulfur Amino Acid Oxidation in Plasma and Erythrocytes in β-Thalassemia Major.

Blood ◽

10.1182/blood.v114.22.4065.4065 ◽

2009 ◽

Vol 114 (22) ◽

pp. 4065-4065

Author(s):

Anurag K. Agrawal ◽

Jung H. Suh ◽

Bruce N. Ames ◽

Elliott P. Vichinsky ◽

Ashutosh Lal

Keyword(s):

Oxidative Stress ◽

Amino Acid ◽

Iron Overload ◽

Metabolic Pathways ◽

Iron Concentration ◽

Thalassemia Major ◽

Healthy Controls ◽

Liver Iron ◽

Redox States ◽

Plasma Compartment

Abstract Abstract 4065 Poster Board III-1000 Background Oxidative stress in β-thalassemia major is a well documented problem thought in part to be due to transfusional iron overload. Sulfur amino acid (SAA)-derived metabolites, chiefly glutathione (GSH), are critical components of cellular antioxidant defense. Inability to adequately regulate endogenous antioxidant status may lead to further exacerbation of oxidative stress. To characterize whether alteration in SAA metabolism contributes to heightened oxidative stress in thalassemia, we utilized a novel liquid chromatography linked electrospray positive tandem mass spectrometric (LC-MS/MS) technique to simultaneously quantify the redox states of cysteine (Cys) and GSH as well as the concentrations of major amino acid-derived metabolites in plasma and erythrocytes. Methods After institutional review board approval, adult and pediatric subjects with β-thalassemia major were recruited for fasting blood samples drawn immediately prior to the next scheduled blood transfusion. Plasma and red blood cell samples were analyzed using the LC-MS/MS technique (J Chromatogr B 2009;in press) and compared with healthy controls. Results Twelve subjects with β-thalassemia major were recruited. The median age of the group was 26.5 years (range 11-41). The median liver iron concentration (LIC) determined by ferritometer was 11.9 mg/g dry-wt (range 1.0-34.8). The median ferritin level for the group was 1980 ng/mL (379-4730). Evidence of myocardial iron overload (T2* <20 msec) was present in 5 of 11 subjects. Plasma SAA redox analysis in these subjects showed significant oxidation of Cys and GSH. Total Cys redox status (Cysteine/2*Cystine ratios) decreased from 0.1 ± 0.01 in healthy controls to 0.08 ± 0.02 in thalassemia (p=0.02). Similarly, the plasma GSH redox state (GSH/2*GSSG ratio) decreased from 38.9 ± 13.7 in healthy controls to 6.7 ± 5.3 in thalassemia subjects (p=0.005). The total GSH and total Cys pools in the plasma did not differ between the two groups. Mirroring the patterns observed in the plasma compartment, the proportion of erythrocyte GSSG was also significantly elevated in thalassemia (0.65% vs. 0.04%, p=0.009), without a concomitant decline in total erythrocyte GSH pool. A significant 3-fold elevation in plasma cystathionine and S-adenosylmethionine levels suggests that key SAA metabolic pathways to augment synthesis of GSH may be up-regulated in thalassemia. In addition to alterations in SAA metabolite profiles, the thalassemia group was >3-fold deficient in plasma valine, spermine and citrulline compared with controls. We found that within this small group, the level of iron overload measured by serum ferritin, liver iron concentration and cardiac MRI T2* showed no correlation with the amount of oxidative stress measured by glutathione redox. Discussion Assessment of SAA redox states and metabolic pathways has the potential to be a novel important marker in β-thalassemia major. The alterations in both Cys and GSH redox states without concomitant decline in their total concentration suggests either a significant increased rate of SAA oxidation and/or a decline in the capacity for NADPH-dependent reduction of oxidized disulfides. The latter may be supported by the evidence of profound hypocitrullinemia in thalassemia, which has been noted in subjects with inherited mitochondrial disorders (Proc Nat Acad Sci U S A 2009;106:3941-5). Finally, we show that the oxidative environment in the plasma affects the transfused erythrocytes which acquire characteristics of abnormal thiol metabolites observed in the plasma compartment. The demonstration of significant oxidative stress even in subjects with low body iron burden suggests that currently acceptable LIC levels may not be optimal, or that other contributors to the pro-oxidant state should be sought in thalassemia. Disclosures: No relevant conflicts of interest to declare.

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Water Only Sequence: An Accurate Method to Estimate Hepatic Siderosis in Patients with Thalassemia Major and Intermedia

Iranian Journal of Radiology ◽

10.5812/iranjradiol.96811 ◽

2020 ◽

Vol 17 (2) ◽

Author(s):

Mehrzad Lotfi ◽

Mohammad Reza Rouhezamin ◽

Bijan Bijan ◽

Sepideh Sefidbakht ◽

Mehran Karimi ◽

...

Keyword(s):

Chemical Shift ◽

Iron Overload ◽

Iron Concentration ◽

Major Complication ◽

Accurate Method ◽

Thalassemia Major ◽

Liver Iron Concentration ◽

Liver Iron ◽

Mr Relaxometry ◽

Sensitivity Specificity

Background: Thalassemia is a common hemoglobinopathy in Iran. Iron overload is a major complication of thalassemia, and an accurate quantification of iron deposition is the mainstay of treatment planning. The liver is the main organ for storage of iron, and quantification of hepatic siderosis is a reliable estimation of total iron overload. Objectives: The aim of this study was to determine the accuracy of chemical shift sequences (CSS), especially a water only sequence (WOS), to estimate hepatic siderosis in thalassemia patients. Patients and Methods: During a seven-month period, from May to December 2016, one hundred and two known cases of thalassemia major and intermedia underwent liver MRI. The liver iron concentration was estimated using T2* MR relaxometry. The iron signal percentage and fraction were calculated using chemical shift sequences and correlated with estimated liver iron concentration (LIC). Results: The correlation coefficient of in-phase and opposed-phase sequences was 0.566 in estimating hepatic siderosis, which was improved by employing water only sequence (0.640). The sensitivity, specificity and positive predictive value were 90.5%, 94.4% and 98.7% for the in-phase and opposed-phase sequences and 82.1%, 94.4% and 98.6% for the water only sequence, respectively. Conclusion: Chemical shift sequences, including a water only sequence, are accurate for the assessment of hepatic siderosis. Water only sequences can effectively minimize the confounding effect of fatty liver.

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A MRI Prospective Survey on Heart and Liver Iron and Cardiac Function in Thalassemia Major Patients Treated with Deferasirox Versus Deferiprone and Desferrioxamine in Monotherapy

Blood ◽

10.1182/blood.v128.22.3631.3631 ◽

2016 ◽

Vol 128 (22) ◽

pp. 3631-3631

Author(s):

Alessia Pepe ◽

Laura Pistoia ◽

Liana Cuccia ◽

Monica Fortini ◽

Vincenzo Caruso ◽

...

Keyword(s):

Iron Overload ◽

Iron Concentration ◽

Thalassemia Major ◽

Left Ventricular ◽

Ventricular Ejection ◽

Left Ventricular Ejection ◽

Myocardial Iron ◽

Liver Iron ◽

Biventricular Function

Abstract Background: No prospective data are available about the efficacy of deferasirox versus deferiprone and desferrioxamine in monotherapy. Our study aimed to prospectively assess the efficacy of deferasirox versus deferiprone and desferrioxamine in monotherapy in a large cohort of thalassemia major (TM) patients by quantitative Magnetic Resonance (MR). Methods: Among the 2551 TM patients enrolled in the MIOT (Myocardial Iron Overload in Thalassemia) network we selected those with an MR follow up study at 18±3 months who had been received one chelator alone between the 2 MR scans. We identified three groups of patients: 235 treated with DFX, 142 with DFP and 162 with DFO. Iron overload was measured by T2* multiecho technique. Liver T2* values were converted into liver iron concentration (LIC) values. Biventricular function parameters were quantitatively evaluated by cine images. Results: Excellent/good levels of compliance were similar in the DFX (98.7%) vs DFP (96.3%) and DFO (97.5%) groups. Among the patients with myocardial iron overload at baseline, in all three groups there was a significant improvement in the global heart T2* value (DFX: +4.58±5.91ms P<0.0001, DFP: 8.53±6.97ms P<0.0001 and DFO: +3.93±5.21 ms P<0.0001) and a reduction in the number of pathological segments (DFX: -4.49±4.55 P<0.0001, DFP: -8.08±5.5.84 ms P=0.001 and DFO: -3.65±3.81 ms P<0.0001). In DFP and in DFO groups there was a significant improvement in left ventricular ejection function (LVEF) (+4.86±6.99% P=0.044 and +3.87±7.48% P=0.004, respectively). Only in the DFP group there was a significant improvement in right ventricular ejection function (RVEF) (6.69±4.61% P=0.001). The improvement in the global heart T2* was significantly lower in the DFX versus the DFP group , but it was not significantly different in the DFX versus the DFO group (Figure 1). The improvement in the LVEF was significantly higher in both DFP and DFO groups than in the DFX group while the improvement in the RVEF was significantly higher in the DFP than in DFX group (Figure 2). Among the patients with hepatic iron at baseline (LIC≥3mg/g dw) the changes were not significantly different in DFX versus the other groups. Conclusions: Prospectively in a large clinical setting of TM patients, DFX monotherapy was significantly less effective than DFP in improving myocardial siderosis and biventricular function and it was significantly less effective than DFO in improving the LVEF. Figure 1 Figure 1. Figure 2 Figure 2. Disclosures Pepe: Chiesi Farmaceutici and ApoPharma Inc.: Other: Alessia Pepe is the PI of the MIOT project, that receives no profit support from Chiesi Farmaceutici S.p.A. and ApoPharma Inc..

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Association Between Cardiac Iron Clereance and Hepatic Siderosis

Blood ◽

10.1182/blood.v128.22.4833.4833 ◽

2016 ◽

Vol 128 (22) ◽

pp. 4833-4833

Author(s):

Alessia Pepe ◽

Laura Pistoia ◽

Domenico D'Ascola ◽

Maria Rita Gamberini ◽

Francesco Gagliardotto ◽

...

Keyword(s):

Iron Overload ◽

Iron Concentration ◽

Thalassemia Major ◽

Hepatic Iron ◽

Liver Iron Concentration ◽

Liver Iron ◽

Cardiac Iron ◽

Follow Up Study ◽

Hepatic Iron Overload

Abstract Introduction. The aim of this multicenter study was to evaluate in thalassemia major (TM) if the cardiac efficacy of the three iron chelators in monotherapy was influenced by hepatic iron levels over a follow up of 18 months. Methods. Among the 2551 TM patients enrolled in the MIOT (Myocardial Iron Overload in Thalassemia) network we evaluated prospectively the 98 patients those with an MR follow up study at 18±3 months who had been received one chelator alone between the 2 MR scans and who showed evidence of significant cardiac iron (global heart T2*<20 ms) at the basal MRI. Iron overload (IO) was measured by T2* multiecho technique. We used cardiac R2* (equal to 1000/T2*) because cardiac R2* is linearly proportional to cardiac iron and hepatic T2* values were converted into liver iron concentration (LIC) values. Results. We identified 3 groups of patients: 47 treated with deferasirox (DFX), 11 treated with deferiprone (DFP) and 40 treated with desferrioxamine (DFO). Percentage changes in cardiac R2* values correlated with changes in LIC in both DFX (R=0.469; P=0.001) and DFP (R=0.775; P=0.007) groups. All patients in these 2 groups who lowered their LIC by more than 50% improved their cardiac iron (see Figure 1). Percentage changes in cardiac R2* were linearly associated to the log of final LIC values in both DFX (R=0.437; P=0.002) and DFP groups (R=0.909; P<0.0001). Percentage changes in cardiac R2* were not predicted by initial cardiac R2* and LIC values. In each chelation group patients were divided in subgroups according to the severity of baseline hepatic iron overload (no, mild, moderate, and severe IO). The changes in cardiac R2* were comparable among subgroups (P=NS) (Figure 2). Conclusion. In patients treated with DFX and DFP percentage changes in cardiac R2* over 18 months were associated with final LIC and percentage LIC changes. In each chelation group percentage changes in cardiac R2* were no influenced by initial LIC or initial cardiac R2*. Figure 1 Figure 1. Figure 2 Figure 2. Disclosures Pepe: Chiesi Farmaceutici and ApoPharma Inc.: Other: Alessia Pepe is the PI of the MIOT project, that receives no profit support from Chiesi Farmaceutici S.p.A. and ApoPharma Inc..

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