Severe Hepatic Iron Overload Research Articles

Magnetic Resonance Imaging T2* Study of Pancreatic and Tissue Iron Overload and Glucose Dysregulation in Young Children with Transfusion Dependent Thalassemia

Abstract Background MRI has become the gold standard for monitoring somatic iron stores. It is assumed that there would be a latency time before pancreatic iron burden could give impaired glucose tolerance. The therapeutic window between clinically silent iron deposition and irreversible pancreatic damage is an appropriate timing for intensification of iron chelation and saving organ function Objective The primary objective of our study is to determine pancreatic, cardiac and hepatic iron overload using MRI T2* in patients with transfusion dependent thalassemia(TDT) and correlate it with type and dose of iron chelation and serum ferritin. The secondary objective is to correlate these findings and the effect on Beta cell function and glucose dysregulation. Subjects and Methods This was a cross sectional study of 50 patients with TDT, 30 (60%) males and 20 (40%) females, aged 7-16 years. Clinical data involved mainly; frequency of transfusion, history of splenectomy, iron chelation therapy and compliance on medications in addition to anthropometric measures and Tanner staging. Laboratory work up included mainly mean pre-transfusion Hb, serum ferritin, serum fructosamine, fasting glucose and insulin levels with calculation of (HOMA-B and HOMA-IR) and MRI T2* to assess Cardiac, liver and pancreatic MRI. Results The mean age was 9.8 ± 2.52 yrs. Almost 40% of adolescents had delayed puberty (Tanner stage 1) of the studied TDT patients, 48% were on Deferasirox, 6% on Deferiprone, 20% was on Deferasirox &Deferiprone and 18% were on Deferiprone & Deferoxamine and two thirds were compliant on iron chelation therapy. Almost 50% were on hydroxyurea. The mean serum ferritin was 2646.6 ± 2334.55ng/ml. 16% had mild hepatic iron overload, 20% had moderate hepatic iron overload while 8% only had severe hepatic iron overload. Regarding the cardiac MRI results, 96% of studied group had no evident cardiac iron overload while 4% had moderate cardiac iron overload and 8% had evidence of severe pancreatic iron overload. The mean fructosamine was 236±56.72, mean HOMA-IR value was 1.4±0.79(0.32-2.5) yet only 4 patients(8%) had HOMA-IR of ≥ 2.5 indicating mild insulin resistance. There was significant positive correlation between LIC(p0.028), fasting glucose(p0.050), insulin level(p > 0.001) and HOMA IR, positive correlation between T2*-weighted MRI pancreas and insulin level (p0.026) as well as positive correlation between mean serum ferritin and insulin level(p0.001),negative non-significant correlation(p0.455) between mean serum ferritin and cardiacMRIT2*. Conclusion In patients with TDT, pancreatic siderosis (late onset presentation) was correlated with hepatic T2*;but not with the cardiac T2* values. Glucose homeostasis and markers of insulin resistance were correlated to pancreatic and liver iron load. Glucose dysregulation may precedes evident pancreatic siderosis so strict iron chelation is essential to maintain B-cell function.

Hepatic and cardiac iron overload quantified by magnetic resonance imaging in patients on hemodialysis: A systematic review and meta-analysis.

Few studies have reported hepatic and cardiac iron overload in patients with end-stage renal disease (ESRD), and the current evidence regarding the prevalence is still scarce. This review aims to estimate the prevalence of hepatic and/or cardiac iron overload quantified by magnetic resonance imaging (MRI) in patients with ESRD who receive hemodialysis (HD), peritoneal dialysis (PD), or have undergone a kidney transplant. A systematic review with meta-analysis was conducted and reported in line with PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) guidelines. MEDLINE and Embase bibliographic databases were searched using a comprehensive list of controlled vocabulary and keywords to identify relevant studies. All studies reporting the prevalence of hepatic and/or cardiac iron overload quantified by MRI in ESRD patients were considered. The Newcastle-Ottawa scale was used to assess the methodological quality of included studies. To investigate the heterogeneity between studies, random-effect meta-analyses for proportions were used. The review comprised seven studies that included 339 patients. Using meta-analysis, the pooled prevalence of severe and mild to moderate hepatic iron overload quantified by MRI was 0.23 [95% CI: 0.08-0.43] and 0.52 [95% CI: 0.47-0.57], respectively. Only three studies included cardiac iron quantification, and none reported iron overload. This review has revealed a high prevalence of severe hepatic iron overload in patients with ESRD treated by HD. Further studies with a larger sample size are needed to determine the impact of iron overload on vital organs in patients with ESRD and guide future research in this understudied field. Proper use of iron chelation and continuous monitoring will help in the early detection of unsolicited complications; however, the low renal clearance of most iron chelators limits the options for treating iron excess in patients with ESRD.

S1419 The Relationship Between Clinical Factors and High Ferritin in Metabolic Surgery Patients With Hepatic Iron Overload

Introduction: Increased serum ferritin is a commonly used blood test that reflects iron stores including liver iron overload. However, the interpretation of ferritin levels is influenced both by iron stores and inflammation. In patients with obesity, ferritin levels may be elevated with iron overload and with inflammation. This study investigated the clinical factors associated with hyperferritinemia in patients with severe obesity and hepatic iron overload. Methods: This study included 4359 patients that had a wedge liver biopsy and documented pre-operative serum ferritin at time of primary metabolic surgery between 2004 and 2021. The standard Perls’/Prussian Blue iron stain was used to diagnose hepatic iron overload. Patients with iron deficiency (ferritin< 30 ng/ml) and extremely high ferritin levels (ferritin >1000 ng/ml) were excluded. Elevated ferritin was defined as 300-999 ng/ml in males and 200-999 ng/ml in females. Clinical data collected on each patient included sex, age, BMI, race/ethnicity, smoking, transferrin saturation, diabetes, hypertension, hyperlipidemia, liver steatosis, liver fibrosis, and type of cells involved in liver iron overload. Multiple logistic regression was used to determine which clinical factors were independently associated with elevated ferritin. Results: The 4351 metabolic surgery patients included 703 (16%) with hepatic iron overload. These 703 patients included 441 (63%) females with a mean age of 47.8 years (SD=10.6), mean BMI of 47.1 kg/m2 (SD=8.1), and 37% (n=258) with elevated ferritin. The types of cells involved with the liver iron overload included Kupffer (34%), hepatocyte (37%), and both (29%) but cell type was not associated with elevated ferritin (p=0.317). Factors that were independently related to high ferritin included increasing levels of steatosis, increasing level of fibrosis, presence of hypertension, normal transferrin saturation (≥20%), male sex, and age 40-59 years (see Table). Conclusion: The histopathological and demographic parameters significantly associated with hyperferritinemia in metabolic surgery patients with hepatic iron overload suggest the role of ferritin in clinical evaluation. The results support the potential association of chronic low-grade systemic inflammation with steatosis, fibrosis, and hypertension when differentiating between hyperferritinemia and normal ferritin levels in patients with severe obesity and excess hepatic iron. Table 1. - Multiple logistic regression for elevated ferritin (versus normal ferritin) within metabolic surgery patients with hepatic parenchymal overload OR 95% CI p-value Steatosis < 5% Reference 5-33% 1.63 [0.98, 2.69] 0.059 34-66% 2.69 [1.44, 5.03] 0.0019 67%+ 6.66 [2.43, 18.24] 0.0002 Fibrosis Grade 0 Reference Grade 1 1.62 [1.06, 2.46] 0.025 Grade 2 2.58 [1.38, 4.81] 0.0029 Hypertension [1.21, 2.45] 0.0024 Yes 1.72 No Reference Transferrin Saturation < 0.0001 ≥20% 2.67 [1.64, 4.35] < 20% Reference Sex [1.08, 2.16] 0.016 Male 1.53 Female Reference Age < 40 Reference 40-59 1.79 [1.17, 2.75] 0.0075 60+ 1.35 [0.74, 2.48] 0.328

Biopsy-based optimization and calibration of a signal-intensity-ratio-based MRI method (1.5 Tesla) in a dextran-iron loaded mini-pig model, enabling estimation of very high liver iron concentrations

ObjectiveMagnetic resonance imaging (MRI)-based techniques for non-invasive assessing liver iron concentration (LIC) in patients with iron overload have a limited upper measuring range around 35 mg/g dry weight, caused by signal loss from accelerated T1-, T2-, T2* shortening with increasing LIC. Expansion of this range is necessary to allow evaluation of patients with very high LIC.AimTo assess measuring range of a gradient-echo R2* method and a T1-weighted spin-echo (SE), signal intensity ratio (SIR)-based method (TE = 25 ms, TR = 560 ms), and to extend the upper measuring range of the SIR method by optimizing echo time (TE) and repetition time (TR) in iron-loaded minipigs.MethodsThirteen mini pigs were followed up during dextran-iron loading with repeated percutaneous liver biopsies for chemical LIC measurement and MRIs for parallel non-invasive estimation of LIC (81 examinations) using different TEs and TRs.ResultsSIR and R2* method had similar upper measuring range around 34 mg/g and similar method agreement. Using TE = 12 ms and TR = 1200 ms extended the upper measuring range to 115 mg/g and yielded good method of agreement.DiscussionThe wider measuring range is likely caused by lesser sensitivity of the SE sequence to iron, due to shorter TE, leading to later signal loss at high LIC, allowing evaluation of most severe hepatic iron overload. Validation in iron-loaded patients is necessary.

Deferoxamine as a Treatment for Cardiac Siderosis Induced Cardiomyopathy Post Liver Transplantation

Introduction Iron overload cardiomyopathy (CM) occurring after liver transplantation in the absence of preexisting myocardial dysfunction or severe hepatic iron overload (ie hemochromatosis) has been described post-mortem. Cardiac siderosis without primary iron overload syndromes was found to be positively correlated to both higher pretransplant transferrin saturation (TSAT) and transfusion of red blood cells. We report an unusual case of a patient with alcohol-induced cirrhosis and heterozygous C282Y mutation who developed a dilated CM post-liver transplant with confirmed cardiac siderosis treated with IV deferoxamine leading to improvement in cardiac function. Case Report A 47-year-old woman with alcohol-induced cirrhosis underwent liver transplantation with a normal pre-operative cardiac evaluation including a transthoracic echocardiogram (TTE) with left ventricular ejection fraction (LVEF) 55-60%. Pre-operative iron studies showed an iron saturation of 91% with ferritin of 156. Her post-op course was uncomplicated, receiving minimal blood products (4 units of packed red blood cells). Two months later she was hospitalized for dyspnea and large pleural effusions. TTE showed depressed LVEF 17%. A cardiac MRI demonstrated a severely dilated LV indexed to BSA (1.5) with severe myocardial siderosis indicated by decreased T2* of 9-14 ms as well as significant mid-wall myocardial fibrosis. Right heart catheterization demonstrated a normal right atrial pressure, wedge pressure 18 mmHg, mean pulmonary pressure 26 mmHg and Fick cardiac index of 2.02 L/min/m2 for which milrinone was initiated. Endomyocardial biopsy confirmed intramyocardial iron deposition and native liver biopsy had grade 2-3 iron deposition. Etiology of her CM post-transplant was attributed to HFE gene heterozygosity in the setting of cirrhosis with post-transplant iron sensitivity (hepcidin depletion). She was initiated on IV chelation therapy with deferoxamine with follow up CMRI showing improved cardiac siderosis indicated by T2* of 13-17 ms with RV function 41% from 20% and LV function 25% from 17%. She was weaned off milrinone and continued on weekly deferoxamine chelation sessions. Summary This case highlights an unusual cause of cardiac siderosis related cardiomyopathy post-liver transplantation treated with IV iron chelation therapy leading to partial LV/RV recovery.

The association between pre-transfusion hemoglobin levels and thalassemia complications

ABSTRACT Objectives To evaluate any association between pre-transfusion hemoglobin (Hb) levels and thalassemia complications and to identify the Hb cutoff values to predict thalassemia complications. Methods We performed a cross-sectional study in thalassemia patients who attended the Adult Hematology Clinic of the tertiary care University Hospital from October 2017 to October 2018. A point-biserial correlation was used to identify any association between Hb levels and thalassemia complications. A receiver operating characteristic (ROC) curve was used to identify the diagnostic ability of Hb levels to predict thalassemia complications and identify Hb cutoff values. Results Out of the 102 patients, there were 53 transfusion dependent thalassemia (TDT) patients and 49 non-transfusion dependent thalassemia (NTDT) patients. In theTDT group, Hb levels showed a negative correlation with severe hepatic iron overload and hypogonadism. The cutoff Hb levels to predict severe hepatic iron overload and hypogonadism were ≤7.01 and 6.81 g/dL, respectively, at which points the area under the ROC curve (AUC) were 0.721 and 0.708, respectively. In the NTDTgroup, Hb levels were negatively correlated with hepatic iron overload, osteoporosis, and pulmonary hypertension. The cutoff values of Hb levels to predict hepatic iron overload, osteoporosis, and pulmonary hypertension were ≤8.24, 7.16, and 7.16 g/dL, respectively, at which points the AUC were 0.923, 0.715, and 0.725, respectively. Conclusions Lower Hb level was associated with more frequent complications in both TDT and NTDT patients. The Hb cutoff levels to predict these complications were identified.

Effectiveness of a top up transfusion programme in preventing cerebrovascular damage in a birth cohort of sickle cell disease

Regular transfusions are effective in managing strokes in paediatric sickle cell patients. However, there are associated risks, including alloimmunisation and iron overload. This study evaluated the efficacy of top-up transfusions in primary and secondary stroke prevention in a single tertiary paediatric centre in Central London. Forty-seven children with sickle cell disease who received transfusions in the last decade were included. No patient on a primary stroke prevention transfusion programme had a cerebrovascular event during the study period but 9.5% on secondary stroke prevention programme did. Twenty-one per cent of patients in this cohort converted to exchange transfusions following transfer to adult services, of which 11% had subsequent strokes. Targeted pre-transfusion haemoglobin S % was not always met; 43% of HbS% readings in a 12- month period were above the set target of 30% and 37% were above the set target of 50%. About a third of patients had evidence of severe hepatic iron overload, but no significant cardiac iron. 25% of patients became alloimmunised, but not severe enough to warrant discontinuation of the transfusion programme. Although transfusions are effective for primary stroke prevention, iron overload remains a significant burden.

SEVERE LIVER IRON CONCENTRATIONS (LIC) IN 24 PATIENTS WITH Β-THALASSEMIA MAJOR: CORRELATIONS WITH SERUM FERRITIN, LIVER ENZYMES AND ENDOCRINE COMPLICATIONS

IntroductionChronic blood transfusion is the mainstay of care for individuals with β-thalassemia major (BTM). However, it causes iron-overload that requires monitoring and management by long-term iron chelation therapy to prevent endocrinopathies and cardiomyopathies, which can be fatal. Hepatic R2 MRI method (FerriScan®) has been validated as the gold standard for evaluation and monitoring liver iron concentration (LIC) that reflects the total body iron-overload. Although adequate oral iron chelation therapy (OIC) is promising for the treatment of transfusional iron-overload, some patients are less compliant with it, and others suffer from long-term effects of iron overload.ObjectiveThe aim of our study was to evaluate the prevalence of endocrinopathies and liver dysfunction, in relation to LIC and serum ferritin level, in a selected group of adolescents and young adult BTM patients with severe hepatic iron overload (LIC from 15 to 43 mg Fe/g dry weight).Patients and MethodsTwenty-four selected BTM patients with severe LIC, due to transfusion-related iron-overload, followed at the Haematology Section, National Centre for Cancer Care and Research, Hamad Medical Corporation of Doha (Qatar), from April 2015 to July 2017, were retrospectively evaluated. The prevalence of short stature, hypogonadism, hypothyroidism, hypoparathyroidism, impaired fasting glucose (IFG), diabetes, and adrenal insufficiency was defined and assessed according to the International Network of Clinicians for Endocrinopathies in Thalassemia (ICET) and American Diabetes Association criteria.ResultsPatients’ most common transfusion frequency was every three weeks (70.8%). At the time of LIC measurements, their median age was 21.5 years with a mean age of 21.7 ± 8.0 years. Mean LIC was 32.05 ± 10.53 mg Fe/g dry weight (range: 15 to 43 mg Fe/g dry weight), and mean serum ferritin level was 4,488.6 ± 2,779 μg/L. LIC was correlated significantly with serum ferritin levels (r = 0.512; p = 0.011). The overall prevalence of short stature was 26.1% (6/23), IFG was 16.7% (4/24), sub-clinical hypothyroidism was 14.3% (3/21), hypogonadotropic hypogonadism was 14.3% (2/14), diabetes mellitus was 12.5% (3/24), and biochemical adrenal insufficiency was 6.7% (1/15). The prevalence of hepatitis C positivity was 20.8% (5/24). No case of clinical hypothyroidism, adrenal insufficiency or hypoparathyroidism was detected in this cohort of patients. The prevalence of IFG impaired fasting glucose was significantly higher in BTM patients with very high LIC (>30 mg Fe/g dry liver) versus those with lower LIC (p = 0.044). The prevalence of endocrinopathies was not significantly different between the two groups of patients with LIC above and below 15 mg Fe/g dry weight.ConclusionsA significant number of BTM patients, with high LIC and endocrine disorders, still exist despite the recent developments of new oral iron chelating agents. Therefore, physicians’ strategies shall optimize early identification of those patients to optimise their chelation therapy and to avoid iron-induced organ damage. We believe that further studies are needed to evaluate if serial measurements of quantitative LIC may predict the risk for endocrine complications. Until these data are available, we recommend a close monitoring of endocrine and other complications, according to the international guidelines.

Life-Threatening Drug-Induced Liver Injury in a Patient with β-Thalassemia Major and Severe Iron Overload on Polypharmacy

A 20-year-old male affected by transfusion-dependent β-thalassemia (β-thal), was prescribed intensive chelation therapy with deferoxamine (DFO) and deferiprone (DFP) because of severe hepatic and cardiac iron overload and β-blocker and warfarin to manage a previous event of atrial fibrillation (AFib) and heart failure. After a few months, he developed critical liver failure, renal tubulopathy and severe electrolyte imbalance. Laboratory and instrumental evaluations were performed to carry out differential diagnosis of acute liver failure and an exclusion diagnosis of drug induced liver injury (DILI) was made. The cholestatic pattern suggested warfarin as the main causative agent and polypharmacy, liver iron overload and heart failure as aggravating factors. Warfarin is a drug commonly prescribed in thalassemia patients who often need polypharmacy for the management of anemia- and iron-related complications. Strict monitoring and multidisciplinary approaches are mandatory to avoid preventable mortality in this fragile population.

Sensitive and non-invasive assessment of hepatocellular iron using a novel room-temperature susceptometer

Liver iron accumulates in various chronic liver diseases where it is an independent factor for survival and carcinogenesis. We tested a novel room-temperature susceptometer (RTS) to non-invasively assess liver iron concentration (LIC). Two hundred and sixty-four patients with or without signs of iron overload or liver disease were prospectively enrolled. Thirty-five patients underwent liver biopsy with semiquantitative iron determination (Prussian Blue staining), atomic absorption spectroscopy (AAS, n=33), or magnetic resonance imaging (MRI, n=15). In vitro studies demonstrated a highly linear (r2=0.998) association between RTS-signal and iron concentration, with a detection limit of 0.3mM. Using an optimized algorithm, accounting for the skin-to-liver capsule distance, valid measurements could be obtained in 84% of cases. LIC-RTS showed a significant correlation with LIC-AAS (r=0.74, p<0.001), LIC-MRI (r=0.64, p<0.001) and hepatocellular iron (r=0.58, p<0.01), but not with macrophage iron (r=0.32, p=0.30). Normal LIC-RTS was 1.4mg/g dry weight. Besides hereditary and transfusional iron overload, LIC-RTS was also significantly elevated in patients with alcoholic liver disease. The areas under the receiver operating characteristic curve (AUROC) for grade 1, 2 and 3 hepatocellular iron overload were 0.72, 0.89 and 0.97, respectively, with cut-off values of 2.0, 4.0 and 5.0mg/g dry weight. Notably, the positive and negative predictive values, sensitivity, specificity and accuracy of severe hepatic iron overload (HIO) (grade ≥2) detection, were equal to AAS and superior to all serum iron markers. Depletion of hepatic iron could be efficiently monitored upon phlebotomy. RTS allows for the rapid and non-invasive measurement of LIC. In comparison to MRI, it could be a cost-effective bedside method for LIC screening. Lay summary: Novel room-temperature susceptometer (RTS) allows for the rapid, sensitive, and non-invasive measurement of liver iron concentration. In comparison to MRI, it could be a cost-effective bedside method for liver iron concentration screening.

Evaluation of cardiac and hepatic iron overload in thalassemia major patients with T2* magnetic resonance imaging

ABSTRACTObjectives: Recent advancements have promoted the use of T2* magnetic resonance imaging (MRI) in the non-invasive detection of iron overload in various organs for thalassemia major patients. This study aims to determine the iron load in the heart and liver of patients with thalassemia major using T2* MRI and to evaluate its correlation with serum ferritin level and iron chelation therapy.Methods: This cross-sectional study included 162 subjects diagnosed with thalassemia major, who were classified into acceptable, mild, moderate, or severe cardiac and hepatic iron overload following their T2* MRI results, respectively, and these were correlated to their serum ferritin levels and iron chelation therapy.Results: The study found that 85.2% of the subjects had normal cardiac iron stores. In contrast, 70.4% of the subjects had severe liver iron overload. A significant but weak correlation (r = −0.28) was found between cardiac T2* MRI and serum ferritin, and a slightly more significant correlation (r = 0.37) was found between liver iron concentration (LIC) and serum ferritin.Discussion: The findings of this study are consistent with several other studies, which show that patients generally manifest with liver iron overload prior to cardiac iron overload. Moreover, iron accumulation demonstrated by T2* MRI results also show a significant correlation to serum ferritin levels.Conclusion: This is the first study of its kind conducted in Indonesia, which supports the fact that T2* MRI is undoubtedly valuable in the early detection of cardiac and hepatic iron overload in thalassemia major patients.

Longitudinal MRI and Ferritin Monitoring of Iron Overload in Chronically Transfused and Chelated Children With Sickle Cell Anemia and Thalassemia Major.

Iron overload is an ineluctable complication in chronically transfused children warranting accurate assessment to avoid related morbidity. We investigated longitudinally the relationships between ferritin levels and hepatic and cardiac T2* magnetic resonance imaging (MRI) in a cohort of chronically transfused children receiving chelation therapy. Thirty children with sickle cell anemia (SCA) and 7 with thalassemia major (TM) chelated similarly by deferasirox were analyzed. Sex ratio, age, median duration of transfusion programs (5 y; range, 2 to 14 y), median transfusion iron intake 0.54 mg/kg/d (range, 0.27 to 0.74 mg/kg/d), and median ferritin level (1550 mg/L; range, 184 to 6204 mg/L) were comparable in TM and SCA. A significant relation was found between ferritin level and transfusion iron intake (P<0.001) despite chelation therapy. Analysis of 73 hepatic T2* MRI performed yearly demonstrated severe hepatic iron overload (≥14 mg/g) in 38.3% cases and a strong relationship between serum ferritin level and liver iron content both in SCA and TM (P<0.001). Analysis of 55 cardiac T2* MRI measurements found no cardiac overload in patients with SCA. Cardiac iron overload was moderate in 4 cases and severe in 1 case of TM. In almost half the cases, ferritin trend correctly predicted hepatic iron trend, both in patients with SCA and TM but failed to predict cardiac iron trend, notably in TM patients. Despite chelation therapy, iron burden in chronically transfused patients remains a threat. Ferritin levels are associated with liver iron overload in chelated children with SCA and TM, but iron burden should be best monitored with MRI whenever the setting allows it.

The Feasibility of Magnetic Resonance Imaging for Quantification of Liver, Pancreas, Spleen, Vertebral Bone Marrow, and Renal Cortex R2* and Proton Density Fat Fraction in Transfusion-Related Iron Overload.

Objective:We aimed to evaluate the feasibility of quantification of liver, pancreas, spleen, vertebral bone marrow, and renal cortex R2* and magnetic resonance imaging-proton density fat fraction (MRI-PDFF) and to evaluate the correlations among them in patients with transfusion-related iron overload.Materials and Methods:A total of 9 patients (5 boys, 4 girls) who were referred to our clinic with suspicion of hepatic iron overload were included in this study. All patients underwent T1-independent volumetric multi-echo gradient-echo imaging with T2* correction and spectral fat modeling. MRI examinations were performed on a 1.5 T MRI system.Results:All patients had hepatic iron overload. Severe hepatic iron overload was recorded in 5/9 patients (56%), and when we evaluated the PDFF maps of these patients, we observed an extensive patchy artifact in the liver in 4 of 5 patients (R2* greater than 671 Hz). When we performed MRI-PDFF measurements despite these artifacts, we observed artifactual high MRI-PDFF values. There was a close correlation between average pancreas R2* and average pancreas MRI-PDFF (p=0.003, r=0.860). There was a significant correlation between liver R2* and average pancreas R2* (p=0.021, r=0.747), liver R2* and renal cortex R2* (p=0.020, r=0.750), and average pancreas R2* and renal cortex R2* (p=0.003, r=0.858). There was a significant negative correlation between vertebral bone marrow R2* and age (p=0.018, r=-0.759).Conclusion:High iron content of the liver, especially with a T2* value shorter than the first echo time can spoil the efficacy of PDFF calculation. Fat deposition in the pancreas is accompanied by pancreatic iron overload. There is a significant correlation between hepatic siderosis and pancreatic siderosis. Renal cortical and pancreatic siderosis are correlated, too.

Transient Elastography of Liver in Hb E Beta Thalassemia: A Novel Tool to Determine Hepatic Iron Overload?

▪Introduction: Transient Elastography (TE) of liver is a well established tool to measure liver stiffness, mainly used for assessment of hepatic fibrosis due to chronic hepatitis. Liver biopsy is the gold standard test for measurement of liver iron concentration (LIC) whereas T2* MRI is the best available non-invasive method for the same in thalassemia. We intended to use hepatic TE as an alternative cheaper tool to assess hepatic iron overload so that it can be applied to larger number of patients.Objective: To assess degree of liver stiffness by TE in patients with HbE beta thalassemia and correlate the findings with LIC calculation by T2* MRI of liver.Materials and Method: 53 patients with HbE beta thalassemia from the thalassemia clinic of Institute of Haematology and Transfusion Medicine, Medical College, Kolkata were enrolled for the study. Patients with known liver disease were excluded. Baseline data like HbE%, mutations, transfusion requirement, growth status, serum ferritin level etc were collected. All of them underwent TE of liver in the School of Digestive and Liver Diseases, IPGMER using the FibroScan Touch 502 machine (Di Marco et al, British Journal of Haematology, Volume 148,3, 476-479, February 2010). 20 randomly selected patients were also assessed by T2*MRI of liver for hepatic iron assessment at the same time. LIC calculation was done from T2* value (J S Hankins et al, Blood, 14 May 2009, Volume 113:20). Data were analyzed by SPSS software-19, IBM.Results: The patients with HbE beta thalassemia had a mean HbE level of 53.66 (±18.45) %. Common beta mutations [mostly IVS-1-5(G-C)] usually found in this part of India, were detected. Mean and median age of the study population was 24.11±13.11 years and 20 years, respectively. Median age of 1st transfusion was 11 years. 35.84% patients were non-transfusion dependent. 39/53 patients had facial deformity and growth retardation. Mean baseline hemoglobin was 7.10±0.76 gm/ dl. Mean serum ferritin level was 3183.66±338.45 ng/ml. TE showed 30.18 % patients had severe liver stiffness (Liver stiffness measurement, LSM >15 kPa) whereas 43.34% had minimum stiffness (LSM≤7 kPa). No significant statistical correlation was found between serum ferritin and LSM. 12/20 patients showed very high calculated LIC (>15 mg/g) and lower T2* value (<1.8 ms) whereas only 10% of them showed mildly elevated calculated LIC. Rest had intermediate LIC.Discussion: There is lack of data regarding hepatic iron overload in HbE beta thalassemia and so also from this part of India. There was a trend that higher the age, higher was the LSM irrespective of the serum ferritin level though not found statistically significant (Figure 1). Serum ferritin level was also not significantly correlated with the calculated LIC in those 20 patients assessed with T2* MRI. 2 patients with mildly elevated LIC had a high ferritin level. Preliminary report indicates that with increase in LSM there was increase in calculated LIC also. Statistical analysis revealed patients with LSM≥7.2 kPa had moderate or severe hepatic iron overload and thus undermine the need for routine T2*MRI. The cut off value signifies that patients with LSM<7.2 kPa might or might not have significantly high liver iron overload, so obviously to be assessed by T2*MRI (Table 1). Therefore use of TE may be an alternative preliminary diagnostic method to gauge hepatic iron overload in HbE beta thalassemia patients. It would be of more value in countries like India where T2* MRI facility is not yet feasible in many centers catering to huge number of HbE-beta thalassemia patients. However, further exploration with larger number of patients is necessary to establish association of LIC and LSM in a more robust way.Conclusion: In resource-poor countries like India, TE may be a relatively cheap tool to be used as a marker of hepatic iron overload in future.Table 1Finding Cut off: ROC (TE-value and LIC categories), n=20Positive if Greater Than or Equal ToaSensitivity1 - Specificity2.31.001.003.41.00.504.4.94.505.7.88.506.2.83.506.5.77.507.2.77.008.2.72.008.85.66.009.45.61.0010.2.55.0011.85.50.0013.85.44.0015.75.38.0018.3.33.0022.9.27.0027.9.22.0035.9.16.0044.7.11.0048.0.05.0049.8.00.00Table 2. The smallest cutoff value is the minimum observed test value minus 1, and the largest cutoff value is the maximum observed test value plus 1. LSM more than 7.2 had a sensitivity of 77.2 % and specificity of 100%. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Transferrin Receptor 2 and HFE Regulate Hepcidin Levels Independently of Bmp6 and Hemojuvelin

Hereditary hemochromatosis (HH) is a genetically heterogeneous disorder characterized by elevated iron absorption from the diet, with consequent iron overload and tissue injury. Adult-onset forms of HH are caused by mutations in the HFE gene and in the gene for transferrin receptor 2 (TFR2). Human patients and mouse models of TFR2 and HFE-related HH show inappropriately low expression of hepcidin, the central regulator of iron metabolism. However, although these genes have been discovered far more than a decade ago, the mechanisms by which HFE and TFR2 influence hepcidin expression remain unclear.The bone morphogenetic protein BMP6 plays a key role in the regulation of hepcidin expression. BMP6 binds to type I (ALK3) and type II serine threonine kinase receptors, and to the coreceptor hemojuvelin (HJV), which phosphorylates intracellular SMAD proteins. Phosphorylated SMADs then bind to SMAD4 and translocate to the nucleus to induce the transcription of hepcidin. Inactivation of Bmp6 or Hjv in mice leads to considerably reduced hepcidin production and severe hepatic iron overload. However, there are major differences in hepcidin expression and extrahepatic tissue iron loading between Bmp6 or Hjv KO males and females, due to the suppressive effect of testosterone on hepcidin in males. In contrast to males, Bmp6-/- and Hjv-/-females still produce some hepcidin and do not massively accumulate iron in the pancreas, heart, or kidneys.The goal of this study was to investigate the role of Hfe and Tfr2 in the residual hepcidin production observed in the absence of Bmp6 in females. We used Bmp6-/-, Tfr2-/-, and B2m-/- mice to generate wild-type, single KO (Bmp6-/-, Tfr2-/-, or B2m-/-) and double KO (Tfr2-/- and Bmp6-/-, or B2m-/- and Bmp6-/-) mice, and we assessed Smad5 phosphorylation, hepcidin expression, and the sites of iron accumulation in the different groups of mice. Notably, B2m-/- mice develop spontaneously hepatic iron overload with a distribution similar to that seen in the liver of Hfe-/-mice and the lack of CD8+ lymphocytes and the absence of classical class I molecules in these mice are not responsible for their iron phenotype.Interestingly, the lack of functional Hfe or the lack of Tfr2 in Bmp6-/- females leads to a very similar phenotype that is much more severe than the single impairment of Bmp6, with massive iron loading in extrahepatic tissues, most notably the exocrine pancreas, the heart, and the kidney. Hepcidin mRNA and pSmad levels in the two categories of double KO females were much more strongly downregulated than in single Bmp6-/- females and, in contrast to Bmp6-/-females, no protein was detectable by ELISA in the double KO mice.Our findings clearly demonstrate that Hfe and Tfr2 regulate hepcidin production independently of Bmp6. The symmetrical phenotype of double Bmp6 and Tfr2, or double Bmp6 and Hfe KO mice suggests that Hfe and Tfr2 could participate in the same signaling complex affecting pSmad levels, even if they do not physically interact. Two complexes, one made of ALK3 and HJV, and the other made of ALK2, ALK3, HFE, and TFR2, very likely affect pSMAD levels independently of each other. Signaling through the second complex occurs in the absence of BMP6 and is most probably initiated by another BMP, for instance BMP2 or BMP4 that are also expressed in the liver and, although not regulated by iron, are capable of stimulating hepcidin expression in hepatocytes. Regulation of hepcidin expression by these two complexes would explain why, whereas Alk3, double Bmp6/Hfe, and double Bmp6/Tfr2 deficient females present with iron overload in extrahepatic tissues as do hepcidin KO mice, Bmp6 and Hjv single KO females present with early-onset iron overload only in the liver, similarly to patients with juvenile HH, and mice KO for Alk2, Hfe, or Tfr2 have the least severe phenotype, comparable with that of patients with adult-onset HH. Notably, TFR2 was also shown to localize in lipid rafts where it promotes MAPK activation. Thus, in addition to its role in the complex affecting pSMAD levels, TFR2 could also regulate hepcidin through a parallel pathway involving ERK1/2 signaling. This would explain the more severe phenotype of mice with combined deletion of Hfe and Tfr2 and the fact that, whereas Tfr2-/- mice do not respond to acute iron loading, Hfe-/-mice still have a significant, although blunted hepcidin response.This work was funded in part by FRM (DEQ2000326528) and ANR (ANR-13-BSV3-0015-01). DisclosuresNo relevant conflicts of interest to declare.

Inactivating Hfe Totally Abolishes Hepcidin Production and Further Aggravates Iron Overload In Bmp6-Deficient Mice

Hepcidin, a circulating hormone produced primarily by the liver, plays a central role in the regulation of systemic iron homeostasis necessary to ensure sufficient availability of iron for hemoglobin synthesis and other metabolic processes while avoiding the oxidative damage to cells that can result from excess free iron. Hepcidin triggers internalization and degradation of ferroportin, the only known iron export channel from cells into the plasma, which leads to the decrease of dietary iron absorption from duodenal enterocytes and to the sequestration of iron recycled from senescent blood cells within macrophages. Iron overload induces the expression of bone morphogenetic protein 6 (BMP6), a member of the TGF-beta superfamily of ligands, which activates a signaling cascade leading to SMAD1/5/8 phosphorylation, translocation of the phosphorylated SMADs bound to SMAD4 to the nucleus, and upregulation of hepcidin gene transcription. Inactivation of Bmp6 in mice leads to considerably reduced hepcidin production, compared with wild-type mice, and severe hepatic iron overload. However, there are major differences in hepcidin expression and extrahepatic tissue iron loading between Bmp6-deficient males and females, due to the suppressive effect of testosterone on hepcidin in males. In contrast to males, Bmp6-/- females still produce some hepcidin and do not massively accumulate iron in their pancreas, their heart or their kidneys.The goal of this study was to investigate the role of Hfe in the residual hepcidin production observed in the absence of Bmp6 in females. Mutations in the HFE gene are causing the most common form of hereditary hemochromatosis, a disorder characterized by a chronic inappropriate increase in dietary iron uptake, progressive iron overload and tissue injury. Human patients and mouse models of HFE-related hemochromatosis show inappropriately low expression of hepcidin. However, the mechanism by which HFE influences hepcidin expression is still unclear. In Hfe-/- mice and in patients with HFE-associated hemochromatosis, the induction of BMP6 mRNA by iron is intact, but hepcidin production is impaired. In the mouse, Hfe and Bmp6 genes are separated by less than 8 cM on chromosome 13, and the probability of obtaining recombinants between the 2 loci is low. However, HFE is a non-classical MHC class 1-like molecule which associates with β2-microglobulin and β2m-/- mice develop spontaneously hepatic iron overload with a distribution similar to that seen in the liver of Hfe-/- mice. We therefore generated β2m/Bmp6 double knockout mice in which the function of both Hfe and Bmp6 is impaired. Briefly, Bmp6-/- mice on a CD1 background were mated to β2m-/- mice on a C57BL/6 background and double heterozygote F1 mice were intercrossed. We assessed Smad1/5/8 phosphorylation, hepcidin expression, and the sites of iron accumulation in wild-type, simple knockout (β2m-/- or Bmp6-/-) and double knockout (β2m-/- and Bmp6-/-) mice of the F2 progeny.Interestingly, the lack of functional Hfe in Bmp6-/- females led to a much more severe phenotype than the single impairment of Bmp6, with massive iron loading in extrahepatic tissues, most notably the exocrine pancreas, the heart, and the proximal and distal convoluted tubules of the kidney. Phosphorylation of Smad1/5/8 in double knockout (β2m-/- and Bmp6-/-) mice was virtually abolished and hepcidin mRNA in double knockout females was much more strongly downregulated than in single Bmp6-/- females. In contrast to Bmp6-/- females, no protein was detectable by ELISA in double knockout mice.Our findings show that Bmp6 and Hfe regulate hepcidin production by two independent pathways that converge on Smad1/5/8 phosphorylation. The role of transferrin receptor 2 (TFR2), another hemochromatosis-associated molecule, remains a key question. The total suppression of hepcidin in mice in which both Hfe and Bmp6 have been impaired suggests that TFR2 does not regulate hepcidin through an additional pathway. Moreover, the observation that Hfe-/-/Tfr2-/- mice have a more severe phenotype than simple Hfe-/- or Tfr2-/- mice favors the interference of Tfr2 with the Bmp6 pathway. Comparison of the phenotype of mice with inactivation of both Bmp6 and Tfr2 to that of Bmp6-/- mice is likely to definitively solve this still open question. Disclosures:No relevant conflicts of interest to declare.

Neonatal hemochromatosis: management, outcome, and prevention

Neonatal hemochromatosis (NH) is a rare disorder but the most common cause of acute liver failure in neonates. NH is characterized by severe hepatic injury and iron overload and is associated with high perinatal mortality and morbidity rates. NH is often preceded by oligohydramnios and intrauterine growth restriction, suggesting an important impact of NH during fetal life. Stillbirth and prematurity are not uncommon. During the last decade, major discoveries on the etiology of NH have radically changed the management and outcome of this disease. NH is now regarded as an alloimmune disease and is, as such, often referred to as gestational alloimmune liver disease. Antenatal treatment with intravenous immunoglobulins starting at 14 weeks' gestation has been shown to prevent the development of NH in subsequent pregnancies. Postnatal treatment, previously based on the use of anti-oxidants and chelation therapy, has now successfully been replaced by exchange transfusions and intravenous immunoglobulins substitution. This review summarizes the latest discoveries on the etiology of NH and the new recommendations concerning its management and prevention.

Hemodialysis-associated Hemosiderosis in the Era of Erythropoiesis-stimulating Agents: A MRI Study

BackgroundMost dialysis patients receiving erythropoesis-stimulating agents (ESA) also receive parenteral iron supplementation. There are few data on the risk of hemosiderosis in this setting. MethodsWe prospectively measured liver iron concentration by means of T1 and T2* contrast magnetic resonance imaging (MRI) without gadolinium, in a cohort of 119 fit hemodialysis patients receiving both parenteral iron and ESA, in keeping with current guidelines. ResultsMild to severe hepatic iron overload was observed in 100 patients (84%; confidence interval, [CI] 76%-90%), of whom 36% (CI, 27%-46%) had severe hepatic iron overload (liver iron concentration >201 μmol/g of dry weight). In the cross-sectional study, infused iron, hepcidin, and C-reactive protein values correlated with hepatic iron stores in both univariate analysis (P<.05, Spearman test) and binary logistic regression (P <.05). In 11 patients who were monitored closely during parenteral iron therapy, the iron dose infused per month correlated strongly with both the overall increase and the monthly increase in liver iron concentration (respectively, rho=0.66, P=.0306 and rho=0.85, P=0.0015, Spearman test). In the 33 patients with iron overload, iron stores fell significantly after iron withdrawal or after a major reduction in the iron dose (first MRI: 220 μmol/g (range: 60-340); last MRI: 50 μmol/g (range: 5-210); P <.0001, Wilcoxon's paired test). ConclusionsMost hemodialysis patients receiving ESA and intravenous iron supplementation have hepatic iron overload on MRI. These findings call for a revision of guidelines on iron therapy in this setting, especially regarding the amount of iron infused and noninvasive methods for monitoring iron stores.

T2* MRI in Regularly Transfused Children with Thalassemia Intermedia: Serum Ferritin Does Not Reflect Liver Iron Stores

Nontransfused patients with thalassemia intermedia (TI) accumulate iron due to increased gastrointestinal absorption of iron. Recent studies using T2* MRI revealed that serum ferritin does not reflect the severity of iron overload in nontransfused TI patients. We evaluated the iron overload status in TI children on monthly transfusion. Based on serum ferritin levels, 11 such patients (mean age 13.18 ± 4.09 years), were classified into two groups, group 1 (six patients) and group 2 (five patients) with serum ferritin levels below and above 1000 ng/mL, respectively. T2* MRI assessments were done for evaluation of hepatic and cardiac iron status. Group 1 and group 2 had mean serum ferritin levels of 817.300 ± 244.690 ng/mL and 1983.80 ± 662.862 ng/mL, respectively (P = .003). T2* MRI showed comparable moderate to severe hepatic iron overload status in both. None of the patients had myocardial iron deposition. We conclude that serum ferritin does not reflect the hepatic iron overload status in our patients with TI on regular transfusion.

Disruption of hemochromatosis protein and transferrin receptor 2 causes iron-induced liver injury in mice

Mutations in hemochromatosis protein (HFE) or transferrin receptor 2 (TFR2) cause hereditary hemochromatosis (HH) by impeding production of the liver iron-regulatory hormone, hepcidin (HAMP). This study examined the effects of disruption of Hfe or Tfr2, either alone or together, on liver iron loading and injury in mouse models of HH. Iron status was determined in Hfe knockout (Hfe(-/-)), Tfr2 Y245X mutant (Tfr2(mut)), and double-mutant (Hfe(-/-) ×Tfr2(mut) ) mice by measuring plasma and liver iron levels. Plasma alanine transaminase (ALT) activity, liver histology, and collagen deposition were evaluated to assess liver injury. Hepatic oxidative stress was assessed by measuring superoxide dismutase (SOD) activity and F(2)-isoprostane levels. Gene expression was measured by real-time polymerase chain reaction. Hfe(-/-) ×Tfr2(mut) mice had elevated hepatic iron with a periportal distribution and increased plasma iron, transferrin saturation, and non-transferrin-bound iron, compared with Hfe(-/-), Tfr2(mut), and wild-type (WT) mice. Hamp1 expression was reduced to 40% (Hfe(-/-) and Tfr2(mut) ) and 1% (Hfe(-/-) ×Tfr2(mut)) of WT values. Hfe(-/-) ×Tfr2(mut) mice had elevated plasma ALT activity and mild hepatic inflammation with scattered aggregates of infiltrating inflammatory cluster of differentiation 45 (CD45)-positive cells. Increased hepatic hydoxyproline levels as well as Sirius red and Masson's Trichrome staining demonstrated advanced portal collagen deposition. Hfe(-/-) and Tfr2(mut) mice had less hepatic inflammation and collagen deposition. Liver F(2) -isoprostane levels were elevated, and copper/zinc and manganese SOD activities decreased in Hfe(-/-) ×Tfr2(mut), Tfr2(mut), and Hfe(-/-) mice, compared with WT mice. Disruption of both Hfe and Tfr2 caused more severe hepatic iron overload with more advanced lipid peroxidation, inflammation, and portal fibrosis than was observed with the disruption of either gene alone. The Hfe(-/-) ×Tfr2(mut) mouse model of iron-induced liver injury reflects the liver injury phenotype observed in human HH.