Prevalence and predictors of cardiac and liver iron overload in patients with thalassemia: A multicenter study based on real-world data

Management of iron overload: lessons from transfusion-dependent hemoglobinopathies

ABSTRACT

Before the advent of effective iron chelation, death from iron-induced cardiomyopathy and endocrine failure occurred in the second decade in patients with thalassemia major, and this experience has driven expectation of poor outcomes and caused anxiety in all disorders associated with iron loading to this day. To be clear, severe iron overload still causes significant morbidity and mortality in many parts of the world, but current understanding of iron metabolism, noninvasive monitoring of organ-specific iron loading in humans, and effective iron chelators have dramatically reduced morbidity of iron overload. Furthermore, clinical experience in hemoglobinopathies supports iron biology learned from animal studies and identifies common concepts in the biology of iron toxicity that inform the management of iron toxicity in several human disorders. The resultant significant increase in survival uncovers new complications due to much longer exposure to anemia and to iron, which must be considered in long-term therapeutic strategies. This review will discuss the management of iron toxicity in patients with hemoglobinopathies and transfusion-dependent anemias and how iron biology informs the clinical approach to treatment.

Correlation between plasma biochemical parameters and cardio-hepatic iron deposition in thalassemia major patients

INTRODUCTION

Major Thalassemia patients suffer from iron overload and organ damage, especially heart and liver damage. Early diagnosis and treatment with a chelator can reduce the complications and mortality of iron overload. Therefore, we aimed to investigate the biochemical and hematological predictors as an alternative and indirect indicator of iron deposition in heart and liver cells in comparison with the MRI T2* method as the gold standard.

MATERIAL AND METHOD

MRI T2* was evaluated in the heart and liver tissues of 62 major beta-thalassemia patients undergoing regular transfusion and chelator therapy. Biochemical and hematological factors were also measured, including serum ferritin, serum electrolytes, liver enzymes, hemoglobin, blood glucose, and serum magnesium. The correlation between these factors was assessed using statistical evaluations.

RESULT

Serum ferritin had a positive and significant correlation with liver siderosis based on MRI T2* (p-value = .015), and no significant association was observed with cardiac siderosis (p-value = .79). However, there was a significant positive correlation between cardiac iron deposition and fasting blood sugar level (p-value = -.049), and plasma level of liver enzymes (alanine aminotransferase (ALT) (p-value = .001), aspartate aminotransferase (AST ((p-value = .01)). Moreover, there was a significant negative correlation between cardiac iron overload and plasma magnesium level (p-value = .014). According to MRI T2*, there was no significant correlation between cardiac and hepatic iron overload (p value = .36).

CONCLUSION

An increase in blood sugar or liver enzymes and a decrease in serum magnesium was associated with an increase in cardiac iron overload based on MRI T2*. Liver iron overload based on MRI T2* had a significant correlation with serum ferritin.

Therapeutic potential and mechanisms of Rifaximin in ameliorating iron overload-induced ferroptosis and liver fibrosis in vivo and in vitro

Liver fibrosis could progress to liver cirrhosis with several contributing factors, one being iron overload which triggers ferroptosis, a form of regulated cell death. Rifaximin, a non-absorbable antibiotic, has shown promise in mitigating fibrosis, primarily by modulating gut microbiota. This study investigated the effects and mechanisms of rifaximin on iron overload-related hepatic fibrosis and ferroptosis. In an iron overload-induced liver fibrosis model in mice and in ferric ammonium citrate (FAC)-stimulated primary hepatocytes, treatment with rifaximin showed significant therapeutic effects. Specifically, it ameliorated the processes of ferroptosis triggered by iron overload, reduced liver injury, and alleviated fibrosis. This was demonstrated by decreased iron accumulation in the liver, improved liver function, and reduced fibrotic area and collagen deposition. Rifaximin also modulated key proteins related to iron homeostasis and ferroptosis, including reduced expression of TFR1, a protein facilitating cellular iron uptake, and increased expression of Fpn and FTH, proteins involved in iron export and storage. In the context of oxidative stress, rifaximin treatment led to a decrease in lipid peroxidation, evidenced by reduced levels of reactive oxygen species (ROS) and malondialdehyde (MDA), and an increase in the reduced glutathione (GSH) and decrease in oxidized glutathione (GSSG). Notably, rifaximin's potential functions were associated with the TGF-β pathway, evidenced by suppressed Tgfb1 protein levels and ratios of phosphorylated to total Smad2 and Smad3, whereas increased Smad7 phosphorylation. These findings indicate rifaximin's therapeutic potential in managing liver fibrosis by modulating the TGF-β pathway and reducing iron overload-induced damage. Further research is required to confirm these results and explore their clinical implications.

Justification of Universal Iron Supplementation for Infants 6-12 months in Regions with a High Prevalence of Thalassemia

Introduction

Many clinicians hesitate to adopt a universal infant iron supplementation program due to the risk of increased iron absorption for those with thalassemia. We aimed to determine thalassemia prevalence in 6- to 12-month-old infants, along with the iron status of those with and without thalassemia.

Methods

We performed a cross-sectional descriptive study of infants attending the Well Baby Clinic at Thammasat University Hospital for routine checkups. Complete blood count, hemoglobin electrophoresis, iron parameters, and molecular genetics for common α- and β-thalassemia were evaluated.

Results

Overall, 97 of 206 (47%) participants had thalassemia minor, the majority having Hb E traits. None had thalassemia intermedia or major. Familial history of anemia or thalassemia presented an increased risk of detecting thalassemia minor in offspring (OR 5.18; 95% CI 2.60-10.33, p=0.001). There were no statistical differences in transferrin saturation, serum ferritin and hepcidin between iron-replete infants with thalassemia minor and those without. However, one-third of infants with thalassemia minor (31/97) also had iron deficiency anemia (IDA), with a similar risk of having iron deficiency to infants without thalassemia. There was no hepcidin suppression in our infants with thalassemia minor as compared to controls.

Conclusions

Both thalassemia and IDA are endemic to Southeast Asia. Infants with thalassemia minor, particularly with Hb E and α-thalassemia traits, are at risk of IDA. Our short-term universal iron supplementation program for 6- to 12-month-old infants does not appear to increase the risk of those with thalassemia minor developing iron overload in the future.

Evaluation of left ventricular function and myocardial deformation in children with beta-thalassemia major by real-time three-dimensional (four-dimensional) and speckle tracking echocardiography

AIM

This study aimed to evaluate the role of real-time three-dimensional (four-dimensional) and speckle tracking echocardiography for early detection of left ventricular systolic dysfunction and also for the relationship between myocardial deformation parameters and myocardial iron load which is measured by cardiac magnetic resonance relaxation time T2* values in asymptomatic children with beta-thalassemia major.

MATERIAL AND METHODS

This multicenter cross-sectional study included 40 patients (mean age 15.4 ± 2.9, 42.1% male) and 40 healthy children whose age, gender, and body mass index-matched with patients. Each participant underwent conventional echocardiography and tissue Doppler imaging. Left ventricular ejection fraction; global longitudinal, circumferential, radial strains; twist; and torsion were measured by real-time three-dimensional and speckle tracking echocardiography. Cardiac magnetic resonance imaging T2* was measured in patients.

RESULTS

Left ventricular global longitudinal, circumferential, and radial strains were decreased despite preserved global ventricular function in patients compared to healthy children (p = p = .029, p = p < .001, p = .003, respectively). There were no statistically significant differences between patients with T2* ≥ 20 ms and patients with T2* < 20 ms for all echocardiographic parameters. Also, there were no significant correlations between all echocardiographic parameters and T2* values in all patients, those with T2* ≥ 20 ms, and T2* < 20 ms.

CONCLUSION

We found that even in asymptomatic children with beta-thalassemia major, left ventricular longitudinal, circumferential and, radial functions were impaired by real-time three-dimensional (four-dimensional) and speckle tracking echocardiography. This novel echocardiographic method might be an important tool for detecting subclinical left ventricular systolic dysfunction irrespective of T2* values.

Resveratrol ameliorates iron overload induced liver fibrosis in mice by regulating iron homeostasis

This study is intended to explore the protective effects of resveratrol (RES) on iron overload-induced liver fibrosis and its mechanism. Iron dextran (50 mg/kg) was injected intraperitoneally in all groups except the control group. Mice in the L-RES, M-RES and H-RES groups were gavaged with RES solution at 25, 50 mg/kg and 100 mg/kg, respectively, 4 h before injection of iron dextran every day; mice in the deferoxamine (DFO) group were injected with DFO intraperitoneally (100 mg/kg); mice in the control group received isovolumetric saline. After seven weeks of RES administration, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) activities and liver hydroxyproline (Hyp) levels were reduced; the malondialdehyde (MDA) activities decreased and the levels of superoxide dismutase (SOD) and glutathione (GSH) were raised. Hematoxylin and eosin (H&E), Prussian, and Masson staining indicated that RES treatment could improve cell damage and reduce hepatic iron deposition and collagen deposition in iron-overload mice. The expression of Bcl-2 was increased, the expression levels of Bax and caspase-3 were decreased under RES treatment. Moreover, RES reduced the expression of hepcidin, ferritin (Ft), divalent metal transporter-1 (DMT-1), transferrin receptor-2 (TFR-2), and raised the expression of ferroprotein-1 (FPN-1). In conclusion, RES could ameliorate iron overload-induced liver fibrosis, and the potential mechanisms may be related to antioxidant, anti-inflammatory, anti-apoptotic, and more importantly, regulation of iron homeostasis by reducing iron uptake and increasing iron export.

Left atrial deformation indices in β-thalassemia major patients

The presence of atrial cardiomyopathy in β-thalassemia major (β-TM) patients complicates their clinical condition. The diagnosis is challenging even with cardiac magnetic resonance (CMR) imaging. Novel echocardiographic techniques are applied to increase the diagnostic yield. Fifty-six β-TM patients and thirty age and sex-matched controls were included in the present cross-sectional study. Heart rate, PR duration, and P axis were measured by electrocardiography, left ventricular ejection fraction (LVEF) and end-diastolic diameter (LVEDD), ratio between early mitral inflow velocity and mitral annular early diastolic velocity (E/e'), left atrial volume index (LAVI), left atrial strain at reservoir (LASr), conduit (LAScd) and contraction (LASct) phases respectively, left ventricular global longitudinal strain (GLS) by echocardiography, and T2* calculation in patient group by CMR. PR duration, LVEF, LAVI, E/e', GLS, and left atrial deformation parameters differed between patients and controls (p <0.05). In patient group, left atrial strain was correlated with PR duration, LAVI, E/e', GLS, and T2* (p <0.05). T2* was correlated only with left atrial deformation indices (p <0.05). Patients with a history of atrial fibrillation were older, had lower heart rate, prolonged PR, increased E/e' and LAVI, and impaired left atrial strain (p <0.05). LASct differed relative to the presence of atrial fibrillation and myocardial iron overload. Atrial strain could be of clinical use in the early detection of atrial cardiomyopathy. An impaired LASct could identify β-TM patients with undetected episodes of atrial fibrillation. Finally, left atrial strain may be helpful in myocardial iron load estimation.

SLN124, a GalNac-siRNA targeting transmembrane serine protease 6, in combination with deferiprone therapy reduces ineffective erythropoiesis and hepatic iron-overload in a mouse model of β-thalassaemia

Beta‐thalassaemia is an inherited blood disorder characterised by ineffective erythropoiesis and anaemia. Consequently, hepcidin expression is reduced resulting in increased iron absorption and primary iron overload. Hepcidin is under the negative control of transmembrane serine protease 6 (TMPRSS6) via cleavage of haemojuvelin (HJV), a co‐receptor for the bone morphogenetic protein (BMP)‐mothers against decapentaplegic homologue (SMAD) signalling pathway. Considering the central role of the TMPRSS6/HJV/hepcidin axis in iron homeostasis, the inhibition of TMPRSS6 expression represents a promising therapeutic strategy to increase hepcidin production and ameliorate anaemia and iron overload in β‐thalassaemia. In the present study, we investigated a small interfering RNA (siRNA) conjugate optimised for hepatic targeting of Tmprss6 (SLN124) in β‐thalassaemia mice (Hbb^th3/+). Two subcutaneous injections of SLN124 (3 mg/kg) were sufficient to normalise hepcidin expression and reduce anaemia. We also observed a significant improvement in erythroid maturation, which was associated with a significant reduction in splenomegaly. Treatment with the iron chelator, deferiprone (DFP), did not impact any of the erythroid parameters. However, the combination of SLN124 with DFP was more effective in reducing hepatic iron overload than either treatment alone. Collectively, we show that the combination therapy can ameliorate several disease symptoms associated with chronic anaemia and iron overload, and therefore represents a promising pharmacological modality for the treatment of β‐thalassaemia and related disorders.

The Importance of Cardiac T2* Magnetic Resonance Imaging for Monitoring Cardiac Siderosis in Thalassemia Major Patients

Objective: Cardiac T2* magnetic resonance imaging (MRI) has recently attracted considerable attention as a non-invasive method for detecting iron overload in various organs in thalassemia major patients. This study aimed to identify the prevalence of cardiac siderosis in thalassemia major patients and evaluate cardiac T2* MRI for monitoring cardiac siderosis before and after patients receive iron chelation therapy and its relation to serum ferritin, left ventricular ejection fraction, and liver iron concentration. The information gathered would be used for the direct monitoring, detection, and treatment of complications early on. Methods: A total of 119 thalassemia major patients were recruited in the present study. The cardiac T2* MRI was compared to serum ferritin levels, liver iron concentration (LIC), and left ventricular ejection fraction. All patients were classified into four groups based on their cardiac siderosis as having normal, marginal, mild to moderate, or severe cardiac iron overload. At the follow-up at years one, three, and five, the cardiac T2* MRI, LIC, serum ferritin, and left ventricular ejection fraction (LVEF) were determined. Results: The prevalence of cardiac siderosis with cardiac T2* MRI ≤ 25 ms was 17.6% (n = 21). There was no correlation between cardiac T2* MRI and serum ferritin, liver iron concentration, and LVEF (p = 0.39, 0.54, and 0.09, respectively). During one year to five years’ follow-up periods, cardiac T2* MRI (ms) in patients with severe cardiac siderosis had significantly improved from 8.5 ± 1.49 at baseline to 33.9 ± 1.9 at five years (p < 0.0001). Patients with severe, mild-moderate, marginal, and no cardiac siderosis had median LIC (mg/g dw) of 23.9 ± 6.5, 21.6 ± 13.3, 25.3 ± 7.7, and 19.9 ± 5.5 at baseline, respectively. Conclusions: This study supports the use of cardiac T2* MRI to monitor cardiac iron overload in patients who have had multiple blood transfusions. Early diagnosis and treatment of patients at risk of cardiac siderosis is a reasonable method of reducing the substantial cardiac mortality burden associated with myocardial siderosis. Cardiac T2* MRI is the best test that can identify at-risk patients who can be managed with optimization of their chelation therapy.

Relation of hepcidin gene expression in blood mononuclear cells with iron overload severity among β-thalassemia major patients

Iron overload is the main cause of morbidity and mortality in β-thalassemia major patients, and cardiac iron overload is the most common reason for death in these transfusion-dependent patients. Hepcidin, a liver-derived peptide hormone, plays a key role in plasma iron levels regulation by controlling two main stages, digestive iron absorption in enterocytes, and iron recycling in macrophages. Although hepcidin is mainly secreted from hepatocytes in the liver, it is also synthesized from mononuclear cells consisting of monocytes and lymphocytes. Binding of this molecule to ferroportin, a specific cellular exporter of iron, leads to degradation of the ligand-receptor complex, which reduces the iron overload by lowering the amounts of iron released into the plasma. Likewise, the same mechanism has been proved to be true for lymphocyte-drived hepcidin. The expression levels of hepcidin mRNA were evaluated using quantitative real time PCR (qRT-PCR) in 50 β-thalassemia major patients, as well as 25 healthy volunteers as the group of control. There was a significantly positive correlation between the cardiac iron concentration, showed by higher T2 values, and hepcidin levels in the patients (p = 0.028; r = 0.311). However, hepcidin expression levels did not significantly correlate with ferritin and liver iron concentrations. Hepcidin can act as a beneficial marker to determine iron overload degrees, particularly in the heart, in β-thalassemia major patients and be used as a logical therapeutic agent for treatment of β-thalassemia disorders.

Twelve-lead and signal-averaged electrocardiographic parameters among beta-thalassemia major patients

BACKGROUND

The majority of beta thalassemia major (β-TM) patients suffer from cardiac disease, while a significant proportion of them die suddenly. Twelve-lead and signal-averaged electrocardiography (SAECG) are simple, inexpensive, readily available tools for identifying an unfavorable arrhythmiological substrate by detecting the presence of arrhythmias, conduction abnormalities, and late potentials (LPs) in these patients.

METHODS

A total of 47 β-TM patients and 30 healthy controls were submitted to 12-lead and signal-averaged electrocardiography. Basic electrocardiographic parameters and prevalence of LPs were recorded. Basic echocardiographic parameters were estimated by transthoracic echocardiography. T2* was calculated by cardiac magnetic resonance imaging wherever available.

RESULTS

β-TM patients demonstrated a more prolonged PR interval (167.74 msec vs 147.07 msec) (P = .043), a higher prevalence of PR prolongation (21.05% vs 0%) (P = .013), and a higher prevalence of LPs (18/47, 38.3% vs 2/30, 6.7%) (P = .002) compared with controls. The prevalence of atrial fibrillation among b-TM patients was estimated at 10.64%. Patients had also greater E/e' ratio (8.35, SD = 2.2 vs 7, SD = 2.07) (P = .012) and LAVI (30.7 mL/m2, SD = 8.76 vs 24.6 mL/m2, SD = 6.57) (P = .002) than controls. Regression analysis showed that QTc and LAVI could correctly predict the presence of LPs in the 80.9% of the patients.

CONCLUSIONS

β-TM patients have a higher prevalence of a prolonged PR interval, atrial fibrillation, and LPs. Twelve-lead and SAECG performance was feasible in all subjects and constitutes a readily available tool for assessing myocardial electrophysiological alterations in this patient group.

Implications of SARSr-CoV 2 infection in thalassemias: Do patients fall into the "high clinical risk" category?

We're all flying blind regarding coronavirus, but it's fair to think if thalassemic patients are particularly vulnerable to SARS-COV-2  infection or are at potential higher risk of complications from COVID-19 than normal population, specially when they become older. The frustrating thing is that, right now,  this virus is still new. It only came to the attention of the World Health Organization at the end of December. Very few cases in thalassemia have so far been reported; is this due to lack of testing or a true lack of infection/susceptibility? However, we believe that more data should be collected to better characterise the impact of SARS-CoV-2 infection in patients with thalassemias. Therefore, a multicenter registry and the collection of comprehensive data from both positive COVID-19 thalassemia major and non-transfusion dependent thalassemia are necessary to clarify debated issues. In the meantime an early and vigilant monitoring along with high quality supportive care are needed in thalassemic patients at high risk for SARS-CoV-2 infection.

Prevalence of left ventricular diastolic dysfunction by cardiac magnetic resonance imaging in thalassemia major patients with normal left ventricular systolic function

Background

The leading cause of mortality of thalassemia major patients is iron overload cardiomyopathy. Early diagnosis with searching for left ventricular diastolic dysfunction before the systolic dysfunction ensued might yield better prognosis. This study aimed to define the prevalence of the left ventricular diastolic dysfunction (LVDD) in thalassemia major patients with normal left ventricular systolic function and the associated factors.

Methods

Adult thalassemia major patients with normal left ventricular systolic function who were referred for cardiac T2* at Siriraj Hospital – Thailand’s largest national tertiary referral center – during the October 2014 to January 2017 study period. Left ventricular diastolic function was defined by mitral valve filling parameters and left atrial volume index using CMR. Patients with moderate to severe valvular heart disease, pericardial disease, or incomplete data were excluded. Baseline characteristics, comorbid diseases, current medication, and laboratory results were recorded and analyzed.

Results

One hundred and sixteen patients were included, with a mean age of 27.5 ± 13.5 years, 57.8% were female, and 87.9% were transfusion dependent. Proportions of homozygous beta-thalassemia and beta-thalassemia hemoglobin E were 12.1 and 87.9%, respectively. The baseline hematocrit was 26.3 ± 3.3%. The prevalence of LVDD was 20.7% (95% CI: 13.7–29.2%). Cardiac T2* was abnormal in 7.8% (95% CI: 3.6–14.2%). Multivariate analysis revealed age, body surface area, homozygous beta-thalassemia, splenectomy, heart rate, and diastolic blood pressure to be significantly associated with LVDD.

Conclusions

LVDD already exists from the early stages of the disease before the abnormal heart T2 * is detected. Homozygous beta-thalassemia and splenectomy were strong predictors of LVDD. These data may increase awareness of the disease, especially in the high risk groups.

Prevalence and Risk Factors for Cardiac and Liver Iron Overload in Adults with Thalassemia in Malaysia

We explored the severity and risk factors for cardiac and liver iron overload (IOL) in 69 thalassemia patients who underwent T2* magnetic resonance imaging (T2* MRI) in a Malaysian tertiary hospital from 2011 to 2015. Fifty-three patients (76.8%) had transfusion-dependent thalassemia (TDT) and 16 (23.2%) had non transfusion-dependent thalassemia (NTDT). Median serum ferritin prior to T2* MRI was 3848.0 μg/L (TDT) and 3971.0 μg/L (NTDT). Cardiac IOL was present in 16 (30.2%) TDT patients and two (12.5%) NTDT patients, in whom severe cardiac IOL defined as T2* <10 ms affected six (11.3%) TDT patients. Liver IOL was present in 51 (96.2%) TDT and 16 (100%) NTDT patients, 37 (69.8%) TDT and 13 (81.3%) NTDT patients were in the most severe category (>15 mgFe/gm dry weight). Serum ferritin showed a significantly strong negative correlation with liver T2* in both TDT (rs = -0.507, p = 0.001) and NTDT (r = -0.762, p = 0.002) but no correlation to cardiac T2* in TDT (r = -0.252, p = 0.099) as well as NTDT (r = -0.457, p = 0.100). For the TDT group, regression analysis showed that cardiac IOL was more severe in males (p = 0.022) and liver IOL was more severe in the Malay ethnic group (p = 0.028) and those with higher serum ferritin levels (p = 0.030). The high prevalence of IOL in our study and the poor correlation between serum ferritin and cardiac T2* underline the need to routinely screen thalassemia patients using T2* MRI to enable the early detection of cardiac IOL.

Cardiac complications and iron overload in beta thalassemia major patients-a systematic review and meta-analysis

Despite the major improvement in therapeutic management of thalassemia major, iron overload is considered a challenging conundrum in these patients and heart disease still remains a major cause of morbidity and mortality in these patients. Therefore, this study aimed to investigate the prevalence of cardiac iron overload and cardiovascular complications in transfusion-dependent thalassemia patients in the worldwide. The following databases were searched: ISI/Web of Science, Embase, PubMed, Scopus, up to February 30, 2018. The quality of the studies was evaluated using the Joanna Briggs Institute Prevalence Critical Appraisal Tool. The random model based on Metaprop was used. One hundred forty-two studies were included. The total number of patients included was 26,893. The mean age of patients was 22.6 (SD = 1.7) years. Based on Metaprop, the overall prevalence of cardiac iron overload/myocardial sidoresis (T2* < 20 ms) and cardiac complications in thalassemia major patients in the worldwide was 25% (95% CI 22-28%) and 42% (95% CI 37-46%), respectively. The results of this study show that the prevalence of cardiac iron overload and cardiovascular complications in patients with thalassemia major is almost high. Therefore, iron chelation and careful monitoring of serum ferritin level will prevent the cardiac iron overload, and interval monitoring of patients with transfusion-dependent thalassemia (TDT) by echocardiography and electrocardiography will help with early detection of cardiovascular complications.

The mechanisms of systemic iron homeostasis and etiology, diagnosis, and treatment of hereditary hemochromatosis

Hereditary hemochromatosis (HH) is a group of genetic iron overload disorders that manifest with various symptoms, including hepatic dysfunction, diabetes, and cardiomyopathy. Classic HH type 1, which is common in Caucasians, is caused by bi-allelic mutations of HFE. Severe types of HH are caused by either bi-allelic mutations of HFE2 that encodes hemojuvelin (type 2A) or HAMP that encodes hepcidin (type 2B). HH type 3, which is of intermediate severity, is caused by bi-allelic mutations of TFR2 that encodes transferrin receptor 2. Mutations of SLC40A1 that encodes ferroportin, the only cellular iron exporter, causes either HH type 4A (loss-of-function mutations) or HH type 4B (gain-of-function mutations). Studies on these gene products uncovered a part of the mechanisms of the systemic iron regulation; HFE, hemojuvelin, and TFR2 are involved in iron sensing and stimulating hepcidin expression, and hepcidin downregulates the expression of ferroportin of the target cells. Phlebotomy is the standard treatment for HH, and early initiation of the treatment is essential for preventing irreversible organ damage. However, because of the rarity and difficulty in making the genetic diagnosis, a large proportion of patients with non-HFE HH might have been undiagnosed; therefore, awareness of this disorder is important.