Identification of a New Mutation in the 5′-UTR of Hepcidin Gene in beta-Thalassemia Major (TM) Patients.

Abstract Hepcidin is a peptide hormone produced in the liver that acts as negative regulator of iron absorption from the enterocytes and of iron release from macrophages. Iron overload and inflammation up-regulate hepcidin synthesis, while anaemia and hypoxia suppress hepcidin expression. Thalassaemia Major (TM) is a hereditary haemolytic anaemia requiring long-life blood transfusions treatment with consequent iron overload. In β-thalassemias is a disorder in which hepcidin is regulated by opposing influences of ineffective erythropoiesis and concomitant iron overload. In order to get further insights on iron regulation in thalassemias, we screened hepcidin and HFE genes in fourty-three TM regularly transfused patients and sixty control subjects. Blood from TM was taken at least 48 hours after chelation therapy and just before blood transfusion. DNA was prepared from peripheral blood, according to standard protocols. Hepcidin and HFE sequences were amplified with PCR using specific primers and PCR products were sequenced, after purification, in a automatic sequencer. Moreover in all patients serum pro-hepcidin was evaluated by ELISA competitive binding assay (DRG,Germany); iron status was evaluated by serum ferritin (SF), percentage of transferrin saturation (TS) by standard procedures and non transferrin bound iron (NTBI) in serum by HPLC after nitrilotriacetic acid (NTA) chelation. Serum IL-6 as inflammation marker was measured by lateral flow immunoassay (Milenia QuickLine, Germany). Molecular analysis detected an undescribed G→T mutation at position +23 of the 5′-untranslated region in two unrelated TM patients; no mutations were found in control subjects. The probands have been regularly transfused since the age of 1 year, receiving 2–3 units of packed red cells and treated with Deferoxamine 40 mg/Kg/day 6 days/week. The first patient, wild type for HFE mutation, was a 29-years-old compound heterozygous IVS II-745/IVS I-110 man. The SF was 1052 ng/ml, TS 94% and NTBI 1.77 μM. Serum pro-hepcidin value was in normal range (213 ng/ml). The proband’s father was heterozygous for the same hepcidin mutation and showed signs of mild iron overload (SF 491 ng/ml and NTBI 0.50 μM). The second patient was a 26-years-old homozygous β039 man with high levels of SF (4346 ng/ml), TS (169%) and NTBI (2.10 μM), while serum pro-hepcidin was 269 ng/ml. HFE analysis revealed a homozygous genotype for H63D mutation. The patient’s mother was heterozygous for hepcidin and H63D mutation and showed mild iron overload (SF 500 ng/ml; NTBI 0.22 μM) whereas the father, heterozygous only for H63D, had normal iron status. According to recent findings (Bridle et al, 2003) our results indicate that hepcidin mutation in association with H63D synergizes the effect on iron homeostasis and it could be responsible for the development of marked iron overload poorly responsive to chelation therapy in β-thalassemia patients.

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Iron Overload in C282Y Heterozygotes: Identification of New Rare HFE Gene Mutants and a Step Strategy for Diagnosis.

Blood ◽

10.1182/blood.v112.11.1859.1859 ◽

2008 ◽

Vol 112 (11) ◽

pp. 1859-1859

Author(s):

Patricia Aguilar-Martinez ◽

Severine Cunat ◽

Fabienne Becker ◽

Francois Blanc ◽

Marlene Nourrit ◽

...

Keyword(s):

Iron Overload ◽

Iron Status ◽

Hereditary Hemochromatosis ◽

Genetic Defect ◽

Transferrin Saturation ◽

Hfe Gene ◽

Compound Heterozygous ◽

Exon 2 ◽

High Iron ◽

Iron Parameters

Abstract Introduction: Homozygozity for the p.Cys282Tyr (C282Y) mutation of the HFE gene is the main genotype associated with the common form of adult hereditary hemochromatosis. C282Y carriers do not usually develop iron overload, unless they have additional risk factors such as liver diseases, a dysmetabolic syndrome or an associated genetic defect. The commonest is the compound heterozygous state for C282Y and the widespread p.His63Asp (H63D) variant allele. However, a few rare HFE mutations can be found on the 6th chromosome in trans, some of which are of clinical interest to fully understand the disorder. Patients and Methods: We recently investigated four C282Y carrier patients with unusually high iron parameters, including increased levels of serum ferritin (SF), high transferrin saturation (TS) and high iron liver content measured by MRI. They were males, aged 37, 40, 42, 47 at diagnosis. Two brothers (aged 40 and 42) were referred separately. The HFE genotype, including the determination of the C282Y, H63D and S65C mutations was performed using PCR-RFLP. HFE sequencing was undertaken using the previously described SCA method (1). Sequencing of other genes (namely, HAMP, HJV/HFE2, SLC40A1, TFR2) was possibly performed in a last step using the same method. Results: We identified three rare HFE mutant alleles, two of which are undescribed, in the four studied patients. One patient bore a 13 nucleotide-deletion in exon 6 (c.[1022_1034del13], p.His341_Ala345>LeufsX119), which is predicted to lead to an abnormal, elongated protein. The two brothers had a substitution of the last nucleotide of exon 2 (c.[340G>A], p.Glu114Lys) that may modify the splicing of the 2d intron. The third patient, who bore an insertion of a A in exon 4 (c.[794dupA],p.[trp267LeufsX80]), has already been reported (1). Discussion: A vast majority of C282Y carriers will not develop iron overload and can be reassured. However, a careful step by step strategy at the clinical and genetic levels may allow to correctly identify those patients deserving further investigation. First, clinical examination and the assessment of iron parameters (SF and TS) allow identifying C282Y heterozygotes with an abnormal iron status. Once extrinsic factors such as heavy alcohol intake, virus or a dysmetabolic syndrome have been excluded, MRI is very useful to authenticate a high liver iron content. Second, HFE genotype must first exclude the presence of the H63D mutation. Compound heterozygozity for C282Y and H63D, a very widespread condition in our area, is usually associated with mild iron overload. Third, HFE sequencing can be undertaken and may identify new HFE variants as described here. The two novel mutations, a frameshift modifying the composition and the length of the C terminal end of the HFE protein and a substitution located at the last base of an exon, are likely to lead to an impaired function of HFE in association with the C282Y mutant. However, it is noteworthy that three of the four patients were diagnosed relatively late, after the 4th decade, as it is the case for C282Y homozygotes. Three further unrelated patients are currently under investigation in our laboratory for a similar clinical presentation. Finally, it can be noted that in those patients who will not have a HFE gene mutant identified, analysis of other genes implicated in iron overload must be performed to search for digenism or multigenism. None of our investigated patients had an additional gene abnormality.

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Iron Overload Is Highly Prevalent in All Disease Severity States in Pyruvate Kinase Deficiency (PKD)

Blood ◽

10.1182/blood.v128.22.2430.2430 ◽

2016 ◽

Vol 128 (22) ◽

pp. 2430-2430

Author(s):

Eduard J van Beers ◽

Wilma Barcellini ◽

Stefan W. Eber ◽

Janet L Kwiatkowski ◽

Jennifer A Rothman ◽

...

Keyword(s):

Iron Overload ◽

Board Of Directors ◽

Disease Severity ◽

Research Funding ◽

Chelation Therapy ◽

Iron Status ◽

Compound Heterozygous ◽

Advisory Committees ◽

Cardiac Iron ◽

Significant Difference

Abstract Background: PKD causes a defect in glycolysis resulting in a hereditary non-spherocytic hemolytic anemia. The prevalence of iron overload is not well described for PKD. Aim: We aim to describe the demographic features and prevalence of iron overload in transfusion dependent and transfusion independent patients with PKD. Methods: Between March 2014 and April 2016, 203 patients enrolled on the PKD Natural History Study at 29 IRB approved sites. All patients were confirmed to have two compound heterozygous or homozygous mutations in the PKLR gene. Children < 1 year of age (n=9) were excluded from this analysis, because elevated ferritin levels are less reliably related to iron overload. Patients were designated with iron overload at the time of enrollment if the plasma ferritin was >1000 ng/mL or the patient was on chelation therapy at any time during the prior 12 months. Patients were designated with having had iron overload if a MRI ever showed liver iron content (LIC) >3 mg/g dry weight or if they had ever received chelation therapy. Tests of association were performed using Fisher's exact test (categorical) and Wilcoxon rank sum test (continuous). Linear associations between variables were measured by Pearson correlation coefficient. P-values <0.05 were considered statistically significant. Results: Of the 194 patients, 111 (57%) were adults ≥18 years and 83 (43%) were children. The median age of enrollment was 20.6 y (range: 1.3-69.9). Splenectomy had been performed in 65% (126/194). Screening ferritin levels were available for 72% (140/194) and LIC for 32% (62/194). At enrollment, 48% (70/147) had iron overload as defined by ferritin and/or current chelation. Using the LIC criterion, iron overload had been present at some point in 86% (95/110) of patients. Ferritin positively correlated with LIC (n=45); r=0.62, p<0.0001. However, of 29 patients with an LIC measurement and a mean ferritin <1000 ng/mL, 15 (52%) had a LIC >3 mg/g DW. Baseline characteristics in patients with and without iron overload are shown in the Table. Notably, even in patients that were never regularly transfused and had a hemoglobin (Hb) >8.7 g/dl, the prevalence of iron overload was 26% (8/31). The frequency of iron overload was significantly higher in patients who had a prior splenectomy (p<0.0001), even after controlling for transfusion history (p<0.0001). Age was associated with iron overload (p=0.046); although, the age range of patients with iron overload was broad (1.3-69.9 years). The frequency of iron overload was significantly higher in those with a lower baselineHb(p=0.004) and higher bilirubin (p=0.03). Data on cardiac iron status was available for 66 patients.Only 2 had cardiac iron overload (defined as T2*<20ms); they were age 5 (T2* 17.8ms, LIC 5 mg/g) and 22 years (T2* 19.7ms, LIC 14 mg/g) at the time of the MRI. Of the 194 patients, 52 (27%) were from the Pennsylvania Amish community. These patients were managed differently than the non-Amish, in that only 2% of the Amish patients were on iron chelation therapy in the 12 months prior to enrollment compared with 43% among the non-Amish cohort. In addition, the Amish had a significant higher prevalence of splenectomy (96% vs 52%, p<0.0001) and proportion who had been historically transfused (79% vs 32%, p<0.0001). Despite these differences, the Amish patients had a lower prevalence of iron overload (34% vs. 51%). There was no significant difference inHbor enrollment age between the Amish and non-Amish cohorts. Conclusion: Iron overload is a common, serious complication in PKD, regardless of age, disease severity, or transfusion status. Although ferritin correlates with LIC for the PKD population overall, at the individual patient level, ferritin is not a good predictor of LIC and a ferritin <1000 ng/ml does not exclude hepatic iron overload. Therefore, we recommend that all patients with PKD starting at age 1 year should be screened annually for iron overload using ferritin and, at least once, using MRI. Disclosures Barcellini: Agios: Consultancy. Neufeld:Novartis: Consultancy. Morton:Agios Pharmaceuticals: Research Funding. Yaish:Octapharma: Other: Study investigator. Kuo:Agios Pharmaceuticals, Inc.: Consultancy, Membership on an entity's Board of Directors or advisory committees; Alexion: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Apotex: Other: unrestricted educational grant; Novartis: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees. Thompson:bluebird bio: Consultancy, Research Funding; Eli Lily: Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Mast: Research Funding; Baxalta (now part of Shire): Research Funding; ApoPharma: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Research Funding; Amgen: Research Funding. Grace:Agios Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees, Research Funding.

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Expression of hepcidin in hereditary hemochromatosis: evidence for a regulation in response to the serum transferrin saturation and to non-transferrin-bound iron

Blood ◽

10.1182/blood-2002-11-3610 ◽

2003 ◽

Vol 102 (1) ◽

pp. 371-376 ◽

Cited By ~ 167

Author(s):

Sven G. Gehrke ◽

Hasan Kulaksiz ◽

Thomas Herrmann ◽

Hans-Dieter Riedel ◽

Karin Bents ◽

...

Keyword(s):

Iron Overload ◽

Serum Ferritin ◽

Iron Homeostasis ◽

Iron Status ◽

Hereditary Hemochromatosis ◽

Transferrin Saturation ◽

Serum Transferrin ◽

Transcript Levels ◽

Hepcidin Expression

Abstract Experimental data suggest the antimicrobial peptide hepcidin as a central regulator in iron homeostasis. In this study, we characterized the expression of human hepcidin in experimental and clinical iron overload conditions, including hereditary hemochromatosis. Using quantitative reverse transcriptase-polymerase chain reaction (RT-PCR), we determined expression of hepcidin and the most relevant iron-related genes in liver biopsies from patients with hemochromatosis and iron-stain-negative control subjects. Regulation of hepcidin mRNA expression in response to transferrin-bound iron, non-transferrin-bound iron, and deferoxamine was analyzed in HepG2 cells. Hepcidin expression correlated significantly with serum ferritin levels in controls, whereas no significant up-regulation was observed in patients with hemochromatosis despite iron-overload conditions and high serum ferritin levels. However, patients with hemochromatosis showed an inverse correlation between hepcidin transcript levels and the serum transferrin saturation. Moreover, we found a significant correlation between hepatic transcript levels of hepcidin and transferrin receptor-2 irrespective of the iron status. In vitro data indicated that hepcidin expression is down-regulated in response to non-transferrin-bound iron. In conclusion, the presented data suggest a close relationship between the transferrin saturation and hepatic hepcidin expression in hereditary hemochromatosis. Although the causality is not yet clear, this interaction might result from a down-regulation of hepcidin expression in response to significant levels of non-transferrin-bound iron. (Blood. 2003;102:371-376)

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Clinical Relevance of Anemia and Transfusion Iron Overload in Myelodysplastic Syndromes

Hematology ◽

10.1182/asheducation-2008.1.166 ◽

2008 ◽

Vol 2008 (1) ◽

pp. 166-175 ◽

Cited By ~ 54

Author(s):

Mario Cazzola ◽

Matteo G. Della Porta ◽

Luca Malcovati

Keyword(s):

Myelodysplastic Syndrome ◽

Iron Overload ◽

Chelation Therapy ◽

Negative Impact ◽

Iron Status ◽

Transferrin Saturation ◽

Thalassemia Major ◽

Suppressive Effect ◽

Clinical Consequences ◽

Production Body

AbstractMost patients with myelodysplastic syndrome eventually become dependent on regular red cell transfusions. This dependency has a negative impact on clinical outcome, primarily because it may be associated with more severe marrow failure. In addition, however, transfusion dependency may involve clinical consequences of chronic anemia and iron overload. Although transfusion iron is primarily taken up by the reticuloendothelial cells, the metal is later redistributed to parenchymal cells. This redistribution is modulated by several factors, including the degree of ineffective erythropoiesis through its suppressive effect on hepcidin production. Body iron status is routinely assessed by serum ferritin and transferrin saturation, but there is a need of reliable tools for locating iron accumulation in patients. Magnetic resonance imaging T2* provides a non-invasive method for detecting and quantifying both liver and myocardial iron overload. Clinical consequences of parenchymal iron overload have been reported not only in thalassemia major, but also in patients with myelodysplastic syndrome. Transfusion-dependent patients with isolated erythroid dysplasia and low risk of leukemic evolution are more likely to develop parenchymal iron overload and its toxicity, and therefore may benefit from chelation therapy. There may also be a benefit of chelation therapy in patients with transfusion iron overload undergoing allogeneic stem cell transplantation. Deferoxamine and deferasirox are currently available for treatment of transfusion iron overload in patients with myelodysplastic syndrome.

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Time to Start Delivering Iron Chelation Therapy in Newly Diagnosed Severe β-Thalassemia

BioMed Research International ◽

10.1155/2020/8185016 ◽

2020 ◽

Vol 2020 ◽

pp. 1-6

Author(s):

Susi Susanah ◽

Ponpon S. Idjradinata ◽

Nur M. Sari ◽

Lulu E. Rakhmilla ◽

Yunia Sribudiani ◽

...

Keyword(s):

Iron Overload ◽

Chelation Therapy ◽

Iron Status ◽

Transferrin Saturation ◽

Iron Chelation ◽

Normal Diet ◽

Iron Chelation Therapy ◽

Newly Diagnosed ◽

Hepcidin Level ◽

Significant Difference

Background. Iron overload is still a major complication of severe β-thalassemia. Indication to start iron chelation therapy is based on serum ferritin (SF) or transferrin saturation (TS) level or the amount of transfusion. The goal of this study is to analyse the pattern of iron status, the amount of transfusion regarding the time to start iron chelator, and serum hepcidin levels in newly diagnosed severe β-thalassemia. Methods. A prospective cohort study was performed at Hasan Sadikin General Hospital on newly diagnosed severe β-thalassemia patients. Subjects had not received any blood transfusion with normal liver function test, CRP, and IL-6 levels who consumed normal diet according to age. The SF and TS levels indicate iron status, while hepcidin level indicates iron regulator status. Main indicator to start iron chelation therapy when SF level ≥1.000 ng/mL, TS level ≥70%, or after receiving transfusion at least 10 times. Statistical analysis used Mann–Whitney and Spearman. Results. Forty-two newly severe β-thalassemia, 30 (71.4%), were diagnosed before 1 year old, mean 9.9 ± 6.4 months, range 2–24 months. Range amount of transfusion until SF level reached ≥1,000 ng/mL were 4-12 times, mean 7 ± 2 times. Mean SF and TS level at diagnosis were 365.6 ± 194.9 ng / mL and 67.3 ± 22.5 % , while hepcidin level was normal, mean 242.6 ± 58 ng / mL . 36/42 patients have reached SF >1000 ng/mL with amount of transfusion less than 10 times. There was no significant difference of SF, TS, and hepcidin levels when SF >1000 ng/mL in the group with amount of transfusion 7–12 and less than 7 ( p = 0.454 , p = 0.084 , p = 0.765 ), respectively. A significant positive correlation between SF and amount of transfusion was observed ( p < 0.001 ; r = 0.781 ). Conclusion. Iron overload in severe β-thalassemia patients might occur earlier even before they received 10 times transfusion. Hepcidin serum level tends to increase when iron overload just started.

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Hepcidin Levels and Their Determinants In Different Types of Myelodysplastic Syndromes

Blood ◽

10.1182/blood.v116.21.4250.4250 ◽

2010 ◽

Vol 116 (21) ◽

pp. 4250-4250

Author(s):

Valeria Santini ◽

Domenico Girelli ◽

Alessandro Sanna ◽

Nicola Martinelli ◽

Lorena Duca ◽

...

Keyword(s):

Iron Overload ◽

Myelodysplastic Syndromes ◽

Iron Homeostasis ◽

Conflicts Of Interest ◽

Iron Status ◽

Transferrin Saturation ◽

Ineffective Erythropoiesis ◽

Transfusion Therapy ◽

Different Types ◽

Serum Hepcidin

Abstract Abstract 4250 Background and Aims. Iron overload is frequently occurring in patients with myelodysplastic syndromes (MDS), with recent data suggesting an impact on both overall and leukemia-free survival1,2. Though prolonged RBC transfusion therapy appears the main contributor, many patients develop iron overload at an early stage of the disease, before the onset of transfusion dependency. It has been postulated that an altered production of hepcidin, the key hormone regulating iron homeostasis, may play a role at this regard. Until recently, studies have been hampered by problems in the development of reliable hepcidin assays, so that only scanty and conflicting data based on semi-quantitative measurement of urinary hepcidin have been reported3,4. This study mainly focused on analyzing serum hepcidin levels in MDS patients by means of a recently validated and improved Mass-Spectrometry based method5. Patients and Methods. One hundred and thirteen consecutive patients (mean age 72.8 ± 9.2 years; 68.1% males) with different types of MDS according to the WHO classification were included in this study. To be enrolled, patients had to be previously untreated or treated only with transfusions. Besides hepcidin, in all subjects we determined serum ferritin, transferrin saturation (TS), non-transferrin-bound-iron (NTBI), along with some putative determinants of hepcidin, like GDF-156 known to be associated with ineffective erythropoiesis, and C-Reactive Protein (CRP) as a surrogate of systemic IL-6 production. Fifty-four healthy individuals (61.1% males) with rigorous definition of normal iron status were used as controls. Main Results. Biochemical markers of iron overload (ferritin and TS), but also CRP and GDF-15 were significantly higher in MDS patients than in controls, even when considering only non-transfused patients. Patients with RARS and the 5q- syndrome appeared as the most iron overloaded, having the highest levels of ferritin, TS, and NTBI. In the whole MDS population, serum hepcidin levels showed a considerable variability, with overall mean values not significantly different from controls [geometric means (gm) with 95% CIs: 5.31 (3.98-7.08) versus 4.2 (3.53-5.0) nM, P=0.28], while the hepcidin/ferritin ratio was significantly lower than in controls [10.1 (7.53-13.53) versus 52.9 (43.6-64.3), P<0.001]. After stratification according to WHO subtypes, hepcidin levels showed significant differences, with the lowest levels in patients with RARS (gm 1.43 nM) and the highest levels in patients with RAEB 1–2 (gm 11.3 nM) and with CMML (gm 10.04 nM) (P=0.003 by ANOVA). The latter groups had substantial elevation of CRP as compared to other MDS subtypes (P=0.008 by ANOVA), while GDF-15 was consistently but uniformly elevated in all MDS subtypes (P=0.97 by ANOVA). Multivariate linear regression models adjusted also for age, sex, and history of RBC transfusions, showed ferritin (β-coefficient 0.45, P=0.002), CRP (β-coefficient 0.21, P=0.02), and different MDS subtypes as the main independent predictors of hepcidin levels. The different degree of correlation between hepcidin and ferritin among the MDS subtypes were analyzed in a general linear model using the F test for slopes. Hepcidin regulation by iron appeared conserved, though relatively blunted in RA, RARS, and 5q- patients, while it was lost in RAEB 1–2 and CMML. Conclusions. Hepcidin levels are consistently heterogeneous in MDS according to different subtypes, likely as the result of the relative strength of competing stimuli. Relative inhibition by ineffective erythropoiesis (but not mediated by GDF-15) seems to prevail particularly in RARS and 5q- syndrome, and is likely to increase the risk of iron overload in these subgroups. On the other hand, patients with RAEB 1–2 and CMML appears to have hepcidin induction that could be driven by cytokines. If confirmed, these results may be relevant not only for a better understanding of iron pathophysiology in MDS, but also for possible future approach with hepcidin modulators7. References: 1) Sanz G, et al. Blood 2008;112: abs 640. 2) Alessandrino EP, et al. Haematologica 2010;95:476-84. 3) Winder A, et al. Br J Haematol 2008;142:669-71. 4) Murphy PT, et al. Br J Haematol 2009;144:451-2. 5) Campostrini N, et al. J Biomed Biotechnol 2010;2010:329646. 6) Tanno T, et al. Nat Med 2007;13:1096-101. 7) Sasu BJ, et al. Blood 2010;115:3616-24. Disclosures: No relevant conflicts of interest to declare.

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Hepcidin Dysregulation in Patients with Type 1 Gaucher’s Disease.

Blood ◽

10.1182/blood.v104.11.3824.3824 ◽

2004 ◽

Vol 104 (11) ◽

pp. 3824-3824

Author(s):

Derralynn A. Hughes ◽

Anna Li ◽

Satish Keshav ◽

Atul Mehta

Keyword(s):

Iron Deficiency ◽

Iron Overload ◽

Gaucher Disease ◽

Iron Status ◽

Negative Regulator ◽

Gaucher's Disease ◽

Gaucher’S Disease ◽

Control Subjects ◽

Type 1 Gaucher Disease

Abstract Gaucher’s Disease is a glycosphingolipid storage disorder where accumulation of glucosylceramide within reticuloendothelial cells results in diverse systemic manifestations. Patients often present with multifactorial anaemia and elevated ferritin which in the context of chronic inflammation may not truly represent their iron status. We have investigated the iron status and the role of of hepcidin, a negative regulator of iron absorption, in our cohort of patients with type 1 Gaucher Disease. Analysis of haematological indices and haematinic parameters of 57 patients with type 1 Gaucher disease revealed 31% males and 29% females to be anaemic. Of these haematinic parameters were consistent with iron deficiency or anaemia of chronic disease in 45.5% and 27.3% of patients respectively. Measurement of the soluble transferrin receptor (sTFR), which is elevated in iron deficiency and reduced in iron overload, allowed the iron status of patients to be further classified. Of 17 patients in whom the sTFR was measured 64.7% where found to have normal levels, 11.7% had elevated levels indicative of iron deficiency, and 23.5% reduced levels indicating iron overload. The mean ferritin was 79ug/l and 547ug/l in these groups respectively. Levels of serum prohepcidin, the 84 amino acid precursor of hepcidin, were measured using a competitive elisa (DRG diagnostics). Levels of prohepcidin in those patients with normal sTFR were comparable to levels in control subjects: 387.2 +/− 305ng/ml compared to 357 +/1 120 ng/ml. In those patients with elevated sTFR and iron deficiency the prohepcidin level was appropriately suppressed to 112.5 +/− 17.6 ng/ml. Similarly levels in anaemic Gaucher patients were lower than those in patients with normal haemoglobin. However, in those patients with low sTFR and high ferritin the prohepcidin measuring 225 +/−35.3 ng/ml was not appropriately elevated compared to control subjects or Gaucher patients with normal iron status. We hypothesize that storage of glucosylceramide within lysosomes of macrophages interferes with their iron sensing mechanisms and secretion of regulatory cytokines. Iron overload is not appropriately detected and hepatocyte synthesis of hepcidin not upregulated. Progressive accumulation of iron may therefore occur.

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Increased Serum Transferrin Saturation Is Associated with Lower Serum Transferrin Receptor Concentration

Clinical Chemistry ◽

10.1093/clinchem/45.12.2191 ◽

1999 ◽

Vol 45 (12) ◽

pp. 2191-2199 ◽

Cited By ~ 16

Author(s):

Anne C Looker ◽

Mark Loyevsky ◽

Victor R Gordeuk

Keyword(s):

Iron Deficiency ◽

Iron Overload ◽

Transferrin Receptor ◽

Iron Status ◽

Transferrin Saturation ◽

Reference Interval ◽

Serum Transferrin ◽

Reactive Protein ◽

Serum Transferrin Receptor ◽

Health And Nutrition

Abstract Background: Serum transferrin receptor (sTfR) concentrations are increased in iron deficiency. We wished to examine whether they are decreased in the presence of potential iron-loading conditions, as reflected by increased transferrin saturation (TS) on a single occasion. Methods: We compared sTfR concentrations between 570 controls with normal iron status and 189 cases with increased serum TS on a single occasion; these latter individuals may be potential cases of iron overload. Cases and controls were selected from adults who had been examined in the third National Health and Nutrition Examination Survey (1988–1994) and for whom excess sera were available to perform sTfR measurements after the survey’s completion. Increased TS was defined as >60% for men and >55% for women; normal iron status was defined as having no evidence of iron deficiency, iron overload, or inflammation indicated by serum ferritin, TS, erythrocyte protoporphyrin, and C-reactive protein. Results: Mean sTfR and mean log sTfR:ferritin were ∼10% and 24% lower, respectively, in cases than in controls (P <0.002). Cases were significantly more likely to have an sTfR value <2.9 mg/L, the lower limit of the reference interval, than were controls (odds ratio = 1.8; 95% confidence interval, 1.04–2.37). Conclusion: Our results support previous studies that suggested that sTfR may be useful for assessing high iron status in populations.

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Hepatic computed tomography for monitoring the iron status of haemodialysis patients with haemosiderosis treated with recombinant human erythropoietin

Clinical Science ◽

10.1042/cs0810113 ◽

1991 ◽

Vol 81 (1) ◽

pp. 113-121 ◽

Cited By ~ 8

Author(s):

Sergio De Marchi ◽

Emanuela Cecchin

Keyword(s):

Computed Tomography ◽

Serum Ferritin ◽

Recombinant Human Erythropoietin ◽

Chelation Therapy ◽

Iron Status ◽

Transferrin Saturation ◽

Ferritin Concentration ◽

Human Erythropoietin ◽

Serum Ferritin Concentration ◽

Erythropoietin Treatment

1. A randomized, partial-crossover study was conducted in uraemic patients with dialysis-associated anaemia and transfusional iron overload to evaluate the effects of desferrioxamine chelation therapy and of recombinant human erythropoietin treatment on hepatic iron storage determined by computed tomography, as well as by serum ferritin concentration and transferrin saturation. 2. Twenty-one haemodialysis patients with moderate iron overload, confirmed by values of serum ferritin concentration, transferrin saturation and hepatic computed tomography density exceeding 1000 μg/l, 45% and 68 Hounsfield units respectively, were randomly allocated to three groups and were followed for 12 months. 3. During the first 6 months group 1 (n = 7) received desferrioxamine chelation therapy (30 mg/kg intravenously three times a week) and group 2 (n = 7) underwent recombinant human erythropoietin treatment (36 units/kg intravenously three times a week). Thereafter, in the second 6 months of observation patients in group 1 were switched to receive recombinant human erythropoietin. Because of a poor response in the desferrioxaminetreated group in the initial 6 months, patients in group 2 continued on the maintenance dose of recombinant human erythropoietin (18 units/kg three times a week) until the end of the trial. Patients in group 3 (n = 7) were maintained on placebo throughout the study. 4. In comparison with placebo, recombinant human erythropoietin treatment, but not desferrioxamine chelation therapy, reduced serum ferritin concentration, transferrin saturation and hepatic computed tomography density, and was associated with a rise in haemoglobin and packed cell volume. Hepatic computed tomography density, serum ferritin concentration and transferrin saturation decreased in 13 out of 14 patients (93%) during treatment with recombinant human erythropoietin. However, when the changes in hepatic computed tomography density were compared with those in the biochemical indices, we observed that the decreases in serum ferritin concentration and transferrin saturation were much slower and delayed. More specifically, within 6 months of starting recombinant human erythropoietin treatment, hepatic computed tomography density was normalized in 13 out of 14 patients (93%), whereas serum ferritin concentration and transferrin saturation were within the normal limits in only two (14%) and six patients (43%), respectively. 5. In conclusion, the strategies for monitoring the iron status of haemodialysis patients with transfusional haemosiderosis may evolve to a new level of sophistication with the introduction of computed tomography scanning. This technique has the advantage of estimating directly the effect of recombinant human erythropoietin treatment on hepatic iron storage. Hepatic computed tomography density is complementary to serum ferritin concentration and transferrin saturation in monitoring the iron status of haemodialysis patients treated with recombinant human erythropoietin.

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Serum Prohepcidin and Iron Homeostasis in Patients with Breast Cancer

Blood ◽

10.1182/blood.v118.21.5291.5291 ◽

2011 ◽

Vol 118 (21) ◽

pp. 5291-5291

Author(s):

Janet G. Grudeva ◽

Ivanka Slavejnova Nenova ◽

Dora Dimitrova Terzieva ◽

Maria Ivanova Spasova ◽

Nikolay Petrov Boyadjiev

Keyword(s):

Breast Cancer ◽

Iron Homeostasis ◽

Conflicts Of Interest ◽

Iron Status ◽

Transferrin Saturation ◽

University Hospital ◽

Direct Result ◽

Full Blood Count ◽

Normocytic Anemia ◽

Cytotoxic Treatment

Abstract Abstract 5291 Introduction: Cancer-related anemia (CRA) has multifactorial etiology and complex pathogenesis. It is defined as normochromic, normocytic anemia with reticulocyto-penia and hypoferremia. Hepcidin is recognized as the central factor in causing CRA. Objective: To investigate the changes in the serum levels of prohepcidin (pHp) and markers of iron homeostasis for gathering more data on the pathogenesis of CRA. Patients and Methods: The authors analyzed prospectively 46 newly diagnosed women with breast cancer, aged 29–72 years (average 47.5±9.0 SD), who had the same clinical stage, histology and hormonal status. They were diagnosed and treated in the Clinic of Oncology and Hematology - University Hospital for a 2-year period (2009–2010). Serum pHp levels and common markers of iron status including serum iron (sFe), transferrin saturation, soluble tranferrin receptor (sTfR), Zn-protoporphyrin (ZPP), ferritin as well as vitamin B12 and folate were measured before treatment initiation and two months afterwards. Serum pHp was determined by a competitive immunotest. All statistical data was computed by the methods of variational and correlation analyses. Results and Discussion: For the two-month follow up interval parameters of full blood count remained without statistically significant deviation. Although the analyzed parameters in the first and second blood samples remained within the reference intervals, the decrease of pHp and the changes of iron-containing substances and ZPP in red blood cells cannot be neglected. However the correlation coefficient (R) between decreased pHp, increased sFe (R=0.314), sTfR (R=0.258), ZPP (R=0.118) and decreased ferritin (R=0.099), were low instead of the expected higher relationship. The obtained results do not support the idea that iron increase and other changes of iron homeostasis in these patients is a direct result of regulatory decrease of pHp. The two-month interval is likely short enough to rule out a potential direct suppressive effect of the specific cytotoxic treatment, and therefore we do not discuss such potential influence on iron homeostasis. Conclusion: Iron homeostasis dysregulation is one of CRA components. In its complex pathogenesis several other factors interfere e.g. such related to the disease; therapy related factors; altered erythropoietin production; activation of cytokines (IL-6 is the major promoter of hepcidin production). Disclosures: No relevant conflicts of interest to declare.

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