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Fukumoto S, Murata T, Osuga Y, Pollock RF. Incidence of Hypophosphatemia After Intravenous Administration of Iron: A Matching-Adjusted Indirect Comparison of Data from Japanese Randomized Controlled Trials. Adv Ther 2023; 40:4877-4888. [PMID: 37702931 PMCID: PMC10567814 DOI: 10.1007/s12325-023-02591-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 06/21/2023] [Indexed: 09/14/2023]
Abstract
INTRODUCTION Intravenous (IV) administration of iron is considered a safe and efficacious treatment for iron deficiency anemia (IDA), recommended in patients requiring rapid replenishment of iron, or intolerant or unresponsive to oral administration of iron. Recent randomized controlled trials (RCTs) have shown high incidence of hypophosphatemia after administration of two IV iron preparations: saccharated ferric oxide (SFO) and ferric carboxymaltose (FCM). The present study aimed to conduct matching-adjusted indirect comparison (MAIC) of hypophosphatemia incidence with these iron formulations and ferric derisomaltose (FDI) based on data from head-to-head RCTs conducted in Japan. METHODS A MAIC of hypophosphatemia incidence was conducted on the basis of data from two head-to-head RCTs. The relative odds of hypophosphatemia with FDI versus SFO were obtained from patient-level data from a recent RCT and adjusted for cumulative iron dose, while parametric models of serum phosphate levels from a separate RCT were used to estimate the relative odds of hypophosphatemia with FCM with SFO. An anchored MAIC was then conducted comparing FDI with FCM. RESULTS The adjusted odds of experiencing hypophosphatemia were significantly lower with FDI than SFO [odds ratio (OR) of 0.02; 95% confidence interval (CI) 0.01-0.05]. The parametric models of serum phosphate from the RCT comparing FCM with SFO provided an estimated OR of 1.17 for the incidence of hypophosphatemia with FCM versus SFO. Combining the two estimates in the MAIC showed that the odds of experiencing hypophosphatemia would be 52.5 (95% CI 27.7-99.4) times higher with FCM than FDI in patients with IDA associated with heavy menstrual bleeding in Japan. CONCLUSIONS Direct comparison of patient-level data and a MAIC from two RCTs in Japanese patients with heavy menstrual bleeding indicated that hypophosphatemia is less frequent in patients treated with FDI than those with FCM or SFO. Results are in agreement with RCTs comparing FDI and FCM in patients with various etiologies conducted in the USA and Europe.
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Affiliation(s)
- Seiji Fukumoto
- Fujii Memorial Institute of Medical Sciences, Institute of Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | | | - Yutaka Osuga
- Department of Obstetrics and Gynecology, University of Tokyo, Tokyo, Japan
| | - Richard F Pollock
- Covalence Research Ltd, Rivers Lodge, West Common, Harpenden, AL5 2JD, UK.
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2
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Glaspy JA, Wolf M, Strauss WE. Intravenous Iron-Induced Hypophosphatemia: An Emerging Syndrome. Adv Ther 2021; 38:3531-3549. [PMID: 34053011 PMCID: PMC8279965 DOI: 10.1007/s12325-021-01770-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 04/30/2021] [Indexed: 12/14/2022]
Abstract
Some, but not all, intravenous iron formulations have been recognized to induce renal phosphate wasting syndrome. Most commonly this has been reported following treatment of iron deficiency anemia (IDA) with ferric carboxymaltose (FCM). A search of PubMed identified relevant randomized controlled trials (RCTs), and case studies evaluating hypophosphatemia (HPP) resulting from intravenous iron treatment. While more recent larger comparative RCTs have confirmed that the majority of patients receiving FCM, especially those with normal renal function, may experience severe HPP, complete documentation is hampered by inconsistent reporting of serum phosphate in such trials. Similarly, while case series and RCTs have documented the persistence of HPP for several weeks or even months, the lack of studies lasting beyond 5–6 weeks has constrained full understanding of the duration of effect. Clinical trials have established that the mechanism involves the bone/metabolic axis with the elevation of intact fibroblast growth factor 23 playing the central role. Reports continue to accumulate of the clinical consequences of severe HPP which are, most commonly, bone abnormalities following repetitive dosing. Case reports and studies, however, have also shown that symptomatic hypophosphatemia can occur after a single FCM dose. The frequency of such events remains unknown, in part due to lack of awareness of hypophosphatemia coupled with the fact that the most common acute symptoms of HPP (fatigue and weakness) are the same for IDA and for many of the chronic diseases that cause IDA. Changes to US and European prescribing information for FCM should raise awareness of the potential for HPP and need to monitor patients at risk for it.
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Affiliation(s)
- John A Glaspy
- Division of Hematology-Oncology, Department of Medicine, UCLA School of Medicine, Los Angeles, CA, 90095, USA.
| | - Myles Wolf
- Division of Nephrology, Department of Medicine, Duke University School of Medicine, Durham, NC, USA
- Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC, USA
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3
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Lecoq AL, Dong C, Carbonnel F, Becquemont L. [Hypophosphatemia following the administration of intravenous iron formulations: A case report and literature review]. Therapie 2021; 76:705-714. [PMID: 33962799 DOI: 10.1016/j.therap.2021.04.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 03/23/2021] [Accepted: 04/13/2021] [Indexed: 12/21/2022]
Abstract
Iron deficiency and iron-deficiency anemia are common medical conditions. Management of the etiology and iron supplementation are both necessary to treat this condition. Use of intravenous iron preparations is increasing due to its advantages over oral iron. Indeed, the total dose required can be provided in a single infusion, and it is more effective and increases hemoglobin levels more quickly than oral iron. Hypophosphatemia, sometimes severe, following intravenous iron administration, has been described in literature these past years, in particular with ferric carboxymaltose. We report here a case of severe hypophosphatemia with ferric carboxymaltose and carry out a literature review to determine the incidence of hypophosphatemia and to precise its clinical presentation, its pathophysiological mechanisms and its treatment. We found that hypophosphatemia is frequent with ferric carboxymaltose. Most of the time, there are no clinical manifestations, but cases of symptomatic osteomalacia have been described. Duration of hypophosphatemia is variable, from a few weeks to several months in case of prolonged administration. Hypophosphatemia owing to renal phosphate wasting is caused by an increase in intact fibroblast growth factor 23 (FGF-23) levels. However, the mechanism of ferric carboxymaltose- induced increase in intact FGF-23 is still unknown.
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Affiliation(s)
- Anne-Lise Lecoq
- Assistance publique-Hôpitaux de Paris (AP-HP), hôpital Bicêtre, Centre de Recherche Clinique AP-HP, université Paris-Saclay, 78, rue du Général-Leclerc, 94270 Le Kremlin-Bicêtre, France.
| | - Catherine Dong
- Service de Gastro-Entérologie, Assistance publique-Hôpitaux de Paris (AP-HP), hôpital Bicêtre, 94270 Le Kremlin-Bicêtre, France
| | - Franck Carbonnel
- Service de Gastro-Entérologie, Assistance publique-Hôpitaux de Paris (AP-HP), hôpital Bicêtre, 94270 Le Kremlin-Bicêtre, France
| | - Laurent Becquemont
- Assistance publique-Hôpitaux de Paris (AP-HP), hôpital Bicêtre, Centre de Recherche Clinique AP-HP, université Paris-Saclay, 78, rue du Général-Leclerc, 94270 Le Kremlin-Bicêtre, France
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4
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Athonvarangkul D, Insogna KL. New Therapies for Hypophosphatemia-Related to FGF23 Excess. Calcif Tissue Int 2021; 108:143-157. [PMID: 32504139 DOI: 10.1007/s00223-020-00705-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 05/12/2020] [Indexed: 12/12/2022]
Abstract
FGF23 is a hormone produced by osteocytes in response to an elevation in the concentration of extracellular phosphate. Excess production of FGF23 by bone cells, or rarely by tumors, is the hormonal basis for several musculoskeletal syndromes characterized by hypophosphatemia due to renal phosphate wasting. FGF23-dependent chronic hypophosphatemia causes rickets and osteomalacia, as well as other skeletal complications. Genetic disorders of FGF23-mediated hypophosphatemia include X-linked hypophosphatemia (XLH), autosomal dominant hypophosphatemic rickets (ADHR), autosomal recessive hypophosphatemic rickets (ARHR), fibrous dysplasia of bone, McCune-Albright syndrome, and epidermal nevus syndrome (ENS), also known as cutaneous skeletal hypophosphatemia syndrome (CSHS). The principle acquired form of FGF23-mediated hypophosphatemia is tumor-induced osteomalacia (TIO). This review summarizes current knowledge about the pathophysiology and clinical presentation of the most common FGF23-mediated conditions, with a focus on new treatment modalities. For many decades, calcitriol and phosphate supplements were the mainstay of therapy. Recently, burosumab, a monoclonal blocking antibody to FGF23, has been approved for treatment of XLH in children and adults, and an active comparator trial in children has shown good efficacy and safety for this drug. The remainder of FGF23-mediated hypophosphatemic disorders continue to be treated with phosphate and calcitriol, although ongoing trials with burosumab for treatment of tumor-induced osteomalacia show early promise. Burosumab may be an effective treatment for the remainder of FGF23-mediated disorders, but clinical trials to support that possibility are at present not available.
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Affiliation(s)
- Diana Athonvarangkul
- Department of Medicine Section of Endocrinology, Yale School of Medicine, PO Box 802080, New Haven, CT, 06520, USA.
| | - Karl L Insogna
- Department of Medicine Section of Endocrinology, Yale School of Medicine, PO Box 802080, New Haven, CT, 06520, USA
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5
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Schaefer B, Tobiasch M, Viveiros A, Tilg H, Kennedy NA, Wolf M, Zoller H. Hypophosphataemia after treatment of iron deficiency with intravenous ferric carboxymaltose or iron isomaltoside-a systematic review and meta-analysis. Br J Clin Pharmacol 2020; 87:2256-2273. [PMID: 33188534 PMCID: PMC8247006 DOI: 10.1111/bcp.14643] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Revised: 10/27/2020] [Accepted: 11/03/2020] [Indexed: 12/21/2022] Open
Abstract
Aims Hypophosphataemia is an increasingly recognized side‐effect of ferric carboxymaltose (FCM) and possibly iron isomaltoside/ferric derisomaltose (IIM), which are used to treat iron deficiency. The aim of this study was to determine frequency, severity, duration and risk factors of incident hypophosphataemia after treatment with FCM and IIM. Methods A systematic literature search for articles indexed in EMBASE, PubMed and Web of Science in years 2005–2020 was carried out using the search terms ‘ferric carboxymaltose’ OR ‘iron isomaltoside’. Prospective clinical trials reporting outcomes on hypophosphataemia rate, mean nadir serum phosphate and/or change in mean serum phosphate from baseline were selected. Hypophosphataemia rate and severity were compared for studies on IIM vs. FCM after stratification for chronic kidney disease. Meta‐regression analysis was used to investigate risk factors for hypophosphataemia. Results Across the 42 clinical trials included in the meta‐analysis, FCM induced a significantly higher incidence of hypophosphataemia than IIM (47%, 95% CI 36–58% vs. 4%, 95% CI 2–5%), and significantly greater mean decreases in serum phosphate (0.40 vs. 0.06 mmol/L). Hypophosphataemia persisted at the end of the study periods (maximum 3 months) in up to 45% of patients treated with FCM. Meta‐regression analysis identified low baseline serum ferritin and transferrin saturation, and normal kidney function as significant predictors of hypophosphataemia. Conclusion FCM is associated with a high risk of hypophosphataemia, which does not resolve for at least 3 months in a large proportion of affected patients. More severe iron deficiency and normal kidney function are risk factors for hypophosphataemia.
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Affiliation(s)
- Benedikt Schaefer
- Department of Medicine I, Gastroenterology, Hepatology and Endocrinology, Medical University of Innsbruck, Innsbruck, Austria.,Christian Doppler Laboratory of Iron and Phosphate Biology, Medical University of Innsbruck, Innsbruck, Austria
| | - Moritz Tobiasch
- Department of Medicine, University Teaching Hospital of Hall in Tirol, Hall, Austria
| | - André Viveiros
- Department of Medicine I, Gastroenterology, Hepatology and Endocrinology, Medical University of Innsbruck, Innsbruck, Austria.,Christian Doppler Laboratory of Iron and Phosphate Biology, Medical University of Innsbruck, Innsbruck, Austria
| | - Herbert Tilg
- Department of Medicine I, Gastroenterology, Hepatology and Endocrinology, Medical University of Innsbruck, Innsbruck, Austria
| | - Nicholas A Kennedy
- IBD Pharmacogenetics, University of Exeter, Exeter, UK.,Gastrointestinal Unit, Western General Hospital, Edinburgh, UK
| | - Myles Wolf
- Department of Medicine, Division of Nephrology, and Duke Clinical Research Institute, Duke University School of Medicine, Durham, NC, USA
| | - Heinz Zoller
- Department of Medicine I, Gastroenterology, Hepatology and Endocrinology, Medical University of Innsbruck, Innsbruck, Austria.,Christian Doppler Laboratory of Iron and Phosphate Biology, Medical University of Innsbruck, Innsbruck, Austria
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6
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Wako Y, Hiratsuka H, Kurotaki T, Tsuchitani M, Umemura T. Relationship between osteoid formation and iron deposition induced by chronic cadmium exposure in ovariectomized rats. J Appl Toxicol 2020; 41:1304-1315. [PMID: 33283302 DOI: 10.1002/jat.4118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 10/24/2020] [Accepted: 11/08/2020] [Indexed: 11/10/2022]
Abstract
Itai-itai (Japanese, "It hurts! It hurts!") disease (IID), a form of osteomalacia, can be induced in ovariectomized rats by long-term administration of cadmium (Cd). This IID rat model shows severe anemia, severe nephropathy, and osteomalacia accompanied by iron (Fe) deposition at the mineralization front. We characterized the pathogenesis of Cd-induced bone lesions by investigating the relationship between Fe deposition and osteoid tissue formation in ovariectomized rats. The rats were injected with CdCl2 (0.5 mg/kg) for 70 weeks, with or without co-injection of erythropoietin (EPO) for varying lengths of time to elucidate whether EPO prevents and/or cures anemia, and, with the restoration from anemia, lessens the osteoid tissue formation. Necropsies were performed at 25, 50, or 70 weeks. Fe deposition at the mineralization front of bone was found at 50 weeks and increased thereafter. Animals injected with EPO showed decreased Fe deposition, although there was no relation between EPO administration and osteoid formation in the femur. Because the increase in bone lesion severity was independent of the amount of Fe deposition, we suggest that Fe deposition is not involved in the etiology of Cd-induced femoral bone lesions.
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Affiliation(s)
- Yumi Wako
- Kashima Laboratory, Nonclinical Research Center, LSI Medience Corporation, Ibaraki, Japan.,Kumamoto Laboratory, Nonclinical Research Center, LSI Medience Corporation, Kumamoto, Japan
| | - Hideaki Hiratsuka
- Head Office for Open Innovation Strategy, Tohoku University, Sendai, Japan
| | - Tetsurou Kurotaki
- Kashima Laboratory, Nonclinical Research Center, LSI Medience Corporation, Ibaraki, Japan
| | - Minoru Tsuchitani
- Kashima Laboratory, Nonclinical Research Center, LSI Medience Corporation, Ibaraki, Japan
| | - Takashi Umemura
- Laboratory of Comparative Pathology, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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7
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Rund D. Intravenous iron: do we adequately understand the short- and long-term risks in clinical practice? Br J Haematol 2020; 193:466-480. [PMID: 33216989 DOI: 10.1111/bjh.17202] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2020] [Accepted: 09/28/2020] [Indexed: 12/31/2022]
Abstract
Intravenous (IV) iron as a therapeutic agent is often administered but not always fully understood. The benefits of IV iron are well proven in many fields, particularly in nephrology. IV iron is beneficial not only for true iron deficiency but also for iron-restricted anaemia (functional iron deficiency). Yet, the literature on intravenous iron has many inconsistencies regarding its adverse effects. Over the last several years, newer forms of iron have been developed, leading to the more regular use of iron and in larger doses. This review will summarize some of the older and newer literature regarding the differences among iron products, including the mechanisms and frequency of their adverse events (AEs). The pathway and frequency of an underrecognized adverse event (hypophosphataemia) will be discussed. Recent insights on infection risk and iron handling by macrophages are examined. Potential but presently unproven risks of iron overload due to IV iron are discussed. The impact of these on the risk:benefit ratio and dosing of intravenous iron are considered in different clinical settings, including pregnancy and cancer. IV iron is an essential component of the therapy of anaemia and understanding these issues will enable more informed treatment decisions and knowledgeable use of these drugs.
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Affiliation(s)
- Deborah Rund
- Hebrew University-Hadassah Medical Organization, Ein Kerem, Jerusalem, Israel
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8
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Min HK, Sung SA, Oh YK, Kim YH, Chung W, Park SK, Ahn C, Lee SW. Hepcidin, iron indices and bone mineral metabolism in non-dialysis chronic kidney disease. Nephrol Dial Transplant 2020; 35:147-154. [PMID: 30053139 DOI: 10.1093/ndt/gfy235] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 06/13/2018] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Few studies have examined the association between hepcidin, iron indices and bone mineral metabolism in non-dialysis chronic kidney disease (CKD) patients. METHODS We reviewed the data of 2238 patients from a large-scale multicenter prospective Korean study (2011-16) and excluded 214 patients with missing data on markers and related medications of iron and bone mineral metabolism, hemoglobin, blood pressure and causes of CKD. Multivariate linear regression analysis was used to identify the association between iron and bone mineral metabolism. RESULTS The proportion of CKD Stages 1-5 were 16.2, 18.7, 37.1, 21.6 and 6.4%, respectively. Per each 10% increase in transferrin saturation (TSAT), there was a 0.013 mmol/L decrease in phosphorus [95% confidence interval (CI) -0.021 to -0.004; P = 0.003] and a 0.022 nmol/L increase in logarithmic 25-hydroxyvitamin D (Ln-25OHD) levels (95% CI 0.005-0.040; P = 0.019). A 1 pmol/L increase in Ln-ferritin was associated with a 0.080 ng/L decrease in Ln-intact parathyroid hormone (Ln-iPTH; 95% CI -0.122 to -0.039; P < 0.001). Meanwhile, beta (95% CI) per 1 unit increase in phosphorus, Ln-25OHD and Ln-iPTH for the square root of the serum hepcidin were 0.594 (0.257-0.932; P = 0.001), -0.270 (-0.431 to -0.108; P = 0.001) and 0.115 (0.004-0.226; P = 0.042), respectively. In subgroup analysis, the relationship between phosphorus, 25OHD and hepcidin was strongest in the positive-inflammation group. CONCLUSIONS Markers of bone mineral metabolism and iron status, including hepcidin, were closely correlated to each other. Potential mechanisms of the relationship warrant further studies.
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Affiliation(s)
- Hyang Ki Min
- Department of Internal Medicine, Eulji Medical Center, Eulji University, Seoul, Korea
| | - Su Ah Sung
- Department of Internal Medicine, Eulji Medical Center, Eulji University, Seoul, Korea
| | - Yun Kyu Oh
- Department of Internal Medicine, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, Korea
| | - Yeong Hoon Kim
- Department of Internal Medicine, Inje University, Busan Paik Hospital, Busan, Korea
| | - Wookyung Chung
- Department of Internal Medicine, Gachon University, Gil Hospital, Incheon, Korea
| | - Sue K Park
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea.,Cancer Research Institute, Seoul National University, Seoul, Korea.,Department of Biomedical Science, Seoul National University Graduate School, Seoul, Korea
| | - Curie Ahn
- Department of Internal Medicine, Seoul National University, Seoul, Korea
| | - Sung Woo Lee
- Department of Internal Medicine, Eulji Medical Center, Eulji University, Seoul, Korea
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Ghafourian K, Shapiro JS, Goodman L, Ardehali H. Iron and Heart Failure: Diagnosis, Therapies, and Future Directions. JACC Basic Transl Sci 2020; 5:300-313. [PMID: 32215351 PMCID: PMC7091506 DOI: 10.1016/j.jacbts.2019.08.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 08/29/2019] [Accepted: 08/29/2019] [Indexed: 12/11/2022]
Abstract
To date, 3 clinical trials have shown symptomatic benefit from the use of intravenous (IV) iron in patients with heart failure (HF) with low serum iron. This has led to recommendations in support of the use of IV iron in this population. However, the systemic and cellular mechanisms of iron homeostasis in cardiomyocyte health and disease are distinct, complex, and poorly understood. Iron metabolism in HF appears dysregulated, but it is still unclear whether the changes are maladaptive and pathologic or compensatory and protective for the cardiomyocytes. The serum markers of iron deficiency in HF do not accurately reflect cellular and mitochondrial iron levels, and the current definition based on the ferritin and transferrin saturation values is broad and inclusive of patients who do not need IV iron. This is particularly relevant in view of the potential risks that are associated with the use of IV iron. Reliable markers of cellular iron status may differentiate subgroups of HF patients who would benefit from cellular and mitochondrial iron chelation rather than IV iron.
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Key Words
- 6MWT, 6-min walk test
- CKD, chronic kidney disease
- DMT1, divalent metal transporter 1 protein
- FCM, ferric carboxymaltose
- FGF, fibroblast growth factor
- Fpn1, ferroportin 1
- Hb, hemoglobin
- I/R, ischemia/reperfusion
- ID, iron deficiency
- IV, intravenous
- LVEF, left ventricular ejection fraction
- NTBI, non–transferrin-bound iron
- NYHA, New York Heart Association
- PGA, Patient Global Assessment
- RCT, randomized clinical trial
- ROS, reactive oxygen species
- TSAT, transferrin saturation
- TfR1, transferrin receptor protein 1
- VO2, peak oxygen uptake
- heart failure
- intravenous iron
- iron chelation
- iron deficiency
- sTfR, soluble transferrin receptor
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Affiliation(s)
| | | | | | - Hossein Ardehali
- Feinberg Cardiovascular and Renal Research Institute, Northwestern University, Chicago, Illinois
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10
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Nataatmadja MS, Francis R. Recurrent severe hypophosphatemia following intravenous iron administration. Clin Case Rep 2020; 8:243-246. [PMID: 32128165 PMCID: PMC7044372 DOI: 10.1002/ccr3.2595] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 07/31/2019] [Accepted: 09/02/2019] [Indexed: 12/24/2022] Open
Abstract
Hypophosphatemia postintravenous iron is frequent but under-recognized. If prolonged or recurrent, it can cause osteomalacia. The likely mechanisms are direct toxicity to proximal tubular cells causing phosphate wasting, elevated Fibroblast growth factor-23 (FGF-23), and reduced 1,25-dihydroxyvitamin D (1,25(OH)2D). Hypophosphatemia may be severe and persist for months, necessitating phosphate replacement until normalization of serum levels occurs.
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Affiliation(s)
- Melissa Stephanie Nataatmadja
- Renal Services Sunshine Coast University Hospital and Health Service Birtinya Australia
- Faculty of Medicine University of Queensland Brisbane Australia
| | - Ross Francis
- Faculty of Medicine University of Queensland Brisbane Australia
- Department of Nephrology Princess Alexandra Hospital Brisbane Australia
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11
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Bartko J, Roschger P, Zandieh S, Brehm A, Zwerina J, Klaushofer K. Hypophosphatemia, Severe Bone Pain, Gait Disturbance, and Fatigue Fractures After Iron Substitution in Inflammatory Bowel Disease: A Case Report. J Bone Miner Res 2018; 33:534-539. [PMID: 29068481 DOI: 10.1002/jbmr.3319] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 10/02/2017] [Accepted: 10/20/2017] [Indexed: 01/12/2023]
Abstract
Intravenous infusions of different iron formulations are recognized as a cause of hypophosphatemia. Chronic hypophosphatemia can alter bone metabolism and bone material structure. As a consequence, osteomalacia may develop and lead to bone fragility. Herein, we report a patient with Crohn's disease presenting with persistent hypophosphatemia and insufficiency fractures while receiving regular iron infusions due to chronic gastrointestinal bleeding. Previously, the patient regularly received vitamin D and also zoledronic acid. The patient underwent bone biopsy of the iliac crest that showed typical signs of osteomalacia with dramatically increased osteoid volume and decreased bone formation. Analysis of the bone mineralization density distribution (BMDD) revealed a more complex picture: On the one hand, there was a shift to higher matrix mineralization, presumably owing to low bone turnover; on the other hand, a broadening of the BMDD indicating more heterogeneous mineralization due to osteomalacia was also evident. This is the first report on changes of bone histomorphometry and bone matrix mineralization in iron-induced osteomalacia. © 2017 American Society for Bone and Mineral Research.
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Affiliation(s)
- Johann Bartko
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Med. Dept., Hanusch Hospital, Vienna, Austria
| | - Paul Roschger
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Med. Dept., Hanusch Hospital, Vienna, Austria
| | - Shahin Zandieh
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Med. Dept., Hanusch Hospital, Vienna, Austria.,Institute of Radiology and Nuclear Medicine, Hanusch Hospital, Vienna, Austria
| | - Attila Brehm
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Med. Dept., Hanusch Hospital, Vienna, Austria
| | - Jochen Zwerina
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Med. Dept., Hanusch Hospital, Vienna, Austria
| | - Klaus Klaushofer
- Ludwig Boltzmann Institute of Osteology at the Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Med. Dept., Hanusch Hospital, Vienna, Austria
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12
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Lim J, Miles L, Litton E. Intravenous Iron Therapy in Patients Undergoing Cardiovascular Surgery: A Narrative Review. J Cardiothorac Vasc Anesth 2017; 32:1439-1451. [PMID: 29246691 DOI: 10.1053/j.jvca.2017.11.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Indexed: 12/26/2022]
Affiliation(s)
- Jolene Lim
- Intensive Care Unit, Fiona Stanley Hospital, Perth, Western Australia, Australia
| | - Lachlan Miles
- Department of Anaesthesia, Austin Health, Melbourne, Australia; Anaesthesia, Perioperative and Pain Medicine Unit, School of Medicine, University of Melbourne, Parkville, Australia
| | - Edward Litton
- Intensive Care Unit, Fiona Stanley Hospital, Perth, Western Australia, Australia; School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia; Australia.
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13
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Adkinson NF, Strauss WE, Bernard K, Kaper RF, Macdougall IC, Krop JS. Comparative safety of intravenous Ferumoxytol versus Ferric Carboxymaltose for the Treatment of Iron Deficiency Anemia: rationale and study design of a randomized double-blind study with a focus on acute hypersensitivity reactions. J Blood Med 2017; 8:155-163. [PMID: 29033620 PMCID: PMC5628663 DOI: 10.2147/jbm.s142236] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Background Intravenous (IV) iron is often used to treat iron deficiency anemia in patients who are unable to tolerate or are inadequately managed with oral iron. However, IV iron treatment has been associated with acute hypersensitivity reactions. The comparative risk of adverse events (AEs) with IV iron preparations has been assessed by a few randomized controlled trials, which are most often limited by small patient numbers, which lack statistical power to identify differences in low-frequency AE such as hypersensitivity reactions. Materials and methods Ferumoxytol versus Ferric Carboxymaltose for the Treatment of Iron Deficiency Anemia (FIRM) is a randomized, double-blind, international, multicenter, Phase III study designed to compare the safety of ferumoxytol and ferric carboxymaltose (FCM). The study includes adults with hemoglobin <12.0 g/dL (females) or <14.0 g/dL (males), transferrin saturation ≤20% or ferritin ≤100 ng/mL within 60 days of dosing, and a history of unsatisfactory or nontolerated oral iron therapy or in whom oral iron therapy is inappropriate. Patients are randomized (1:1) to ferumoxytol 510 mg or FCM 750 mg, each given intravenously on days 1 and 8. Primary end points are the incidence of moderate-to-severe hypersensitivity reactions, including anaphylaxis, and moderate-to-severe hypotension. All potential hypersensitivity and hypotensive reactions will be adjudicated by a blinded, independent Clinical Events Committee. A secondary safety end point is the composite frequency of moderate-to-severe hypersensitivity reactions, including anaphylaxis, serious cardiovascular events, and death. Secondary efficacy end points include mean change in hemoglobin and mean change in hemoglobin per milligram of iron administered from baseline to week 5. Urinary excretion of phosphorus and the occurrence of hypophosphatemia after IV iron administration will be examined as well as the mechanisms of such hypophosphatemia in a substudy. Conclusion FIRM will provide data on the comparative safety of ferumoxytol and FCM, two IV iron preparations with similar dosing schedules, focusing on moderate-to-severe hypersensitivity reactions, including anaphylaxis, and moderate-to-severe hypotension. The study plans to enroll 2000 patients and is expected to complete in 2017.
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Affiliation(s)
- N Franklin Adkinson
- Department of Medicine, Division of Allergy and Clinical Immunology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Sanai T, Ono T, Fukumitsu T. Beneficial Effects of Oral Iron in Japanese Patients on Hemodialysis. Intern Med 2017; 56:2395-2399. [PMID: 28824065 PMCID: PMC5643164 DOI: 10.2169/internalmedicine.8520-16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 02/17/2017] [Indexed: 11/30/2022] Open
Abstract
Objective Iron deficiency anemia (IDA) has become important with regard to mortality in hemodialysis (HD) patients. Therefore, it is necessary to optimize the treatment of these patients. Methods IDA in end-stage renal disease patients on HD was observed in 42 (33.6%) of 125 patients. We examined the influence of daily orally iron [sodium ferrous citrate (SFC) iron/tablet 50 mg, 1-2 tablets] on the renal function markers, anemia and iron data for about 6 months. Results The hematocrit and hemoglobin levels were significantly increased in the patients treated with SFC [hematocrit: before 28.5%±2.1% (mean ± standard deviation), 1st month 30.0%±2.3%, p<0.05; 3rd month 32.4%±2.9%, p<0.05; 6th month 31.3%±3.4%, p<0.05; and hemoglobin: before 9.25±0.70, 1st month 9.72±0.71, p<0.05; 3rd month 10.54±0.96, p<0.05; 6th month 10.25±1.21 g/dL, p<0.05]. The transferrin saturation (TSAT) and serum ferritin levels were significantly increased in the patients treated with SFC (TSAT: before 21.5%±10.0%, 1st-3rd month, 34.1%±15.1%, p<0.05; 6-8th month 34.7%±11.9%, p<0.05; and ferritin: before 38.2±37.1, 6-8th month 67.5±44.0 ng/mL, p<0.05). The present findings clearly indicate that oral iron is an effective route of iron supplementation in HD patients, and no adverse effects associated with SFC occurred during the treatment and follow-up period. Conclusion Our results clearly indicate that oral iron delivered via SFC is a well-tolerated and effective form of iron supplementation in long-term HD and IDA patients in Japan.
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Affiliation(s)
- Toru Sanai
- The Division of Nephrology, Department of Internal Medicine, Fukumitsu Hospital, Japan
| | - Takashi Ono
- The Division of Nephrology, Department of Internal Medicine, Fukumitsu Hospital, Japan
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Nomoto H, Miyoshi H, Nakamura A, Nagai S, Kitao N, Shimizu C, Atsumi T. A case of osteomalacia due to deranged mineral balance caused by saccharated ferric oxide and short-bowel syndrome: A case report. Medicine (Baltimore) 2017; 96:e8147. [PMID: 28953654 PMCID: PMC5626297 DOI: 10.1097/md.0000000000008147] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
RATIONALE Saccharated ferric oxide has been shown to lead to elevation of fibroblast growth factor 23, hypophosphatemia, and, consequently, osteomalacia. Moreover, mineral imbalance is often observed in patients with short-bowel syndrome to some degree. PATIENT CONCERNS A 62-year-old woman with short-bowel syndrome related with multiple resections of small intestines due to Crohn disease received regular intravenous administration of saccharated ferric oxide. Over the course of treatment, she was diagnosed with tetany, which was attributed to hypocalcemia. Additional assessments of the patient revealed not only hypocalcemia, but also hypophosphatemia, hypomagnesemia, osteomalacia, and a high concentration of fibroblast growth factor 23 (314 pg/mL). DIAGNOSES We diagnosed her with mineral imbalance-induced osteomalacia due to saccharated ferric oxide and short-bowel syndrome. INTERVENTIONS Magnesium replacement therapy and discontinuation of saccharated ferric oxide alone. OUTCOMES These treatments were able to normalize her serum mineral levels and increase her bone mineral density. LESSONS This case suggests that adequate evaluation of serum minerals, including phosphate and magnesium, during saccharated ferric oxide administration may be necessary, especially in patients with short-bowel syndrome.
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Affiliation(s)
- Hiroshi Nomoto
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University
| | - Hideaki Miyoshi
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University
| | - Akinobu Nakamura
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University
| | - So Nagai
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University
| | - Naoyuki Kitao
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University
| | - Chikara Shimizu
- Division of Laboratory and Transfusion Medicine, Hokkaido University Hospital, Sapporo, Japan
| | - Tatsuya Atsumi
- Department of Rheumatology, Endocrinology and Nephrology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University
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A Case of an Insufficiency Fracture of the Medial Proximal Tibia Secondary to Osteomalacia Associated with Long-Term Saccharated Ferric Oxide Administration. Case Rep Orthop 2017; 2017:1675654. [PMID: 28744387 PMCID: PMC5514337 DOI: 10.1155/2017/1675654] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Accepted: 06/04/2017] [Indexed: 11/18/2022] Open
Abstract
This article presents a case of insufficiency fracture of medial proximal tibia caused by long-term administration of saccharated ferric oxide (SFO) in a 77-year-old female. In this case, 2-year administration of SFO for iron deficit anemia induced hypophosphatemic osteomalacia and finally resulted in an insufficiency fracture of medial proximal tibia. Hypophosphatemia and pain due to the insufficiency fracture were recovered promptly by withdrawing SFO administration and rest. This case represented varus deformity of the knee associated with osteoarthritis, which may also cause the insufficiency fracture of medial proximal tibia in addition to osteomalacia due to long-term administration of SFO. Long-term SFO administration should be avoided because of a definitive risk of osteomalacia and fragile fracture.
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Kalra PA, Bhandari S. Efficacy and safety of iron isomaltoside (Monofer(®)) in the management of patients with iron deficiency anemia. Int J Nephrol Renovasc Dis 2016; 9:53-64. [PMID: 27022297 PMCID: PMC4790490 DOI: 10.2147/ijnrd.s89704] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
New intravenous (IV) iron preparations should ideally be capable of delivering a wide dosing range to allow iron correction in a single or low number of visits, a rapid infusion (doses up to 1,000 mg must be administered over more than 15 minutes and doses exceeding 1,000 mg must be administered over 30 minutes or more), and minimal potential side effects including low catalytic/labile iron release with minimal risk of anaphylaxis. Furthermore, they should be convenient for the patient and health-care professional, and cost effective for the health-care system. The intention behind the development of iron isomaltoside (Monofer(®)) was to fulfill these requirements. Iron isomaltoside has been shown to be effective in treating iron deficiency anemia across multiple therapeutic patient groups and compared to placebo, IV iron sucrose, and oral iron. Iron isomaltoside consists of iron and a carbohydrate moiety where the iron is tightly bound in a matrix structure. It has a low immunogenic potential, a low potential to release labile iron, and does not appear to be associated with clinically significant hypophosphatemia. Due to the structure of iron isomaltoside, it can be administered in high doses with a maximum single dosage of 20 mg/kg body weight. Clinical trials and observational studies of iron isomaltoside show that it is an effective and well-tolerated treatment of anemia across different therapeutic areas with a favorable safety profile.
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Affiliation(s)
- Philip A Kalra
- Department of Renal Medicine, Salford Royal NHS Foundation Trust, Salford, UK
| | - Sunil Bhandari
- Hull and East Yorkshire Hospitals NHS Trust, Hull, UK; Hull York Medical School, Hull, UK
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Intravenous iron administration and hypophosphatemia in clinical practice. Int J Rheumatol 2015; 2015:468675. [PMID: 26000018 PMCID: PMC4426778 DOI: 10.1155/2015/468675] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 04/12/2015] [Accepted: 04/19/2015] [Indexed: 12/20/2022] Open
Abstract
Introduction. Parenteral iron formulations are frequently used to correct iron deficiency anemia (IDA) and iron deficiency (ID). Intravenous formulation efficacy on ferritin and hemoglobin level improvement is greater than that of oral formulations while they are associated with lower gastrointestinal side effects. Ferric carboxymaltose- (FCM-) related hypophosphatemia is frequent and appears without clinical significance. The aim of this study was to assess the prevalence, duration, and potential consequences of hypophosphatemia after iron injection. Patients and Methods. The medical records of all patients who underwent parenteral iron injection between 2012 and 2014 were retrospectively reviewed. Pre- and postinjection hemoglobin, ferritin, plasma phosphate, creatinine, and vitamin D levels were assessed. Patients who developed moderate (range: 0.32–0.80 mmol/L) or severe (<0.32 mmol/L) hypophosphatemia were questioned for symptoms. Results. During the study period, 234 patients received iron preparations but 104 were excluded because of missing data. Among the 130 patients included, 52 received iron sucrose (FS) and 78 FCM formulations. Among FS-treated patients, 22% developed hypophosphatemia versus 51% of FCM-treated patients, including 13% who developed profound hypophosphatemia. Hypophosphatemia severity correlated with the dose of FCM (p = 0.04) but not with the initial ferritin, hemoglobin, or vitamin D level. Mean hypophosphatemia duration was 6 months. No immediate clinical consequence was found except for persistent fatigue despite anemia correction in some patients. Conclusions. Hypophosphatemia is frequent after parenteral FCM injection and may have clinical consequences, including persistent fatigue. Further studies of chronic hypophosphatemia long-term consequences, especially bone assessments, are needed.
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Endo I, Fukumoto S, Ozono K, Namba N, Inoue D, Okazaki R, Yamauchi M, Sugimoto T, Minagawa M, Michigami T, Nagai M, Matsumoto T. Nationwide survey of fibroblast growth factor 23 (FGF23)-related hypophosphatemic diseases in Japan: prevalence, biochemical data and treatment. Endocr J 2015; 62:811-6. [PMID: 26135520 DOI: 10.1507/endocrj.ej15-0275] [Citation(s) in RCA: 105] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
A nationwide epidemiologic survey of fibroblast growth factor 23 (FGF23)-related hypophosphatemic diseases was conducted in 2010 to clarify the prevalence and the clinical presentations of the disorders. A questionnaire inquiring the experience of patients with these diseases was sent to randomly selected hospitals throughout Japan. The estimated annual incidence of the diseases was 117 cases (95% CI 75 - 160), 55 males (95% CI 30 - 81) and 62 females (95% CI 40 - 84). Tumor-induced osteomalacia (TIO) and X-linked hypophosphatemic rickets (XLH) were the most prevalent causes of acquired and genetic FGF23-related hypophosphatemic diseases, respectively. The estimated incidence of XLH was about 1 in 20,000. We have also collected clinical data of the patients by a secondary survey. These patients showed FGF23 levels of above 30 pg/mL by intact assay in the presence of hypophosphatemia. While complete resection of responsible tumors improved biochemical abnormalities in patients with TIO, treatment with phosphate and/or active vitamin D3 did not normalize serum phosphate and tubular maximum transport of phosphate in patients with XLH. Our results suggest that there is no racial difference in the incidence of XLH. While FGF23 measurement is useful for the diagnosis of FGF23-related hypophosphatemic diseases, the better management is necessary especially for patients with genetic hypophosphatemic rickets caused by excessive actions of FGF23.
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Affiliation(s)
- Itsuro Endo
- Department of Hematology, Endocrinology & Metabolism Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima 770-8503 Japan
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Abstract
Recent studies of inherited disorders of phosphate metabolism have shed new light on the understanding of phosphate metabolism. Phosphate has important functions in the body and several mechanisms have evolved to regulate phosphate balance including vitamin D, parathyroid hormone and phosphatonins such as fibroblast growth factor-23 (FGF23). Disorders of phosphate homeostasis leading to hypo- and hyperphosphataemia are common and have clinical and biochemical consequences. Notably, recent studies have linked hyperphosphataemia with an increased risk of cardiovascular disease. This review outlines the recent advances in the understanding of phosphate homeostasis and describes the causes, investigation and management of hypo- and hyperphosphataemia.
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Affiliation(s)
- P Manghat
- Department of Chemical Pathology, Darent Valley Hospital, Dartford, UK
| | - R Sodi
- Department of Biochemistry, NHS Lanarkshire, East Kilbride, UK
| | - R Swaminathan
- Department of Chemical Pathology, St. Thomas Hospital, London, UK
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Tejera Segura B, Martínez-Morillo M, Cañellas J, Holgado S. [Arthralgias and fractures in an adult male: beyond hypovitaminosis D]. Med Clin (Barc) 2014; 142:423-4. [PMID: 24035413 DOI: 10.1016/j.medcli.2013.06.024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 06/13/2013] [Accepted: 06/20/2013] [Indexed: 11/28/2022]
Affiliation(s)
- Beatriz Tejera Segura
- Servicio de Reumatología, Hospital Germans Trias i Pujol, Badalona, Barcelona, España.
| | | | - Jeronima Cañellas
- Servicio de Reumatología, Hospital Germans Trias i Pujol, Badalona, Barcelona, España
| | - Susana Holgado
- Servicio de Reumatología, Hospital Germans Trias i Pujol, Badalona, Barcelona, España
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A randomized, open-label, non-inferiority study of intravenous iron isomaltoside 1,000 (Monofer) compared with oral iron for treatment of anemia in IBD (PROCEED). Am J Gastroenterol 2013; 108:1877-88. [PMID: 24145678 PMCID: PMC3853365 DOI: 10.1038/ajg.2013.335] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2013] [Accepted: 07/03/2013] [Indexed: 12/11/2022]
Abstract
OBJECTIVES In the largest head-to-head comparison between an oral and an intravenous (IV) iron compound in patients with inflammatory bowel disease (IBD) so far, we strived to determine whether IV iron isomaltoside 1,000 is non-inferior to oral iron sulfate in the treatment of iron deficiency anemia (IDA). METHODS This prospective, randomized, comparative, open-label, non-inferiority study was conducted at 36 sites in Europe and India. Patients with known intolerance to oral iron were excluded. A total of 338 IBD patients in clinical remission or with mild disease, a hemoglobin (Hb) <12 g/dl, and a transferrin saturation (TSAT) <20% were randomized 2:1 to receive either IV iron isomaltoside 1,000 according to the Ganzoni formula (225 patients) or oral iron sulfate 200 mg daily (equivalent to 200 mg elemental iron; 113 patients). An interactive web response system method was used to randomize the eligible patient to the treatment groups. The primary end point was change in Hb from baseline to week 8. Iron isomaltoside 1,000 and iron sulfate was compared by a non-inferiority assessment with a margin of -0.5 g/dl. The secondary end points, which tested for superiority, included change in Hb from baseline to weeks 2 and 4, change in s-ferritin, and TSAT to week 8, number of patients who discontinued study because of lack of response or intolerance of investigational drugs, change in total quality of life (QoL) score to weeks 4 and 8, and safety. Exploratory analyses included a responder analysis (proportion of patients with an increase in Hb ≥2 g/dl after 8 weeks), the effect of regional differences and total iron dose level, and other potential predictors of the treatment response. RESULTS Non-inferiority in change of Hb to week 8 could not be demonstrated. There was a trend for oral iron sulfate being more effective in increasing Hb than iron isomaltoside 1,000. The estimated treatment effect was -0.37 (95% confidence interval (CI): -0.80, 0.06) with P=0.09 in the full analysis set (N=327) and -0.45 (95% CI: -0.88, -0.03) with P=0.04 in the per protocol analysis set (N=299). In patients treated with IV iron isomaltoside 1,000, the mean change in s-ferritin concentration was higher with an estimated treatment effect of 48.7 (95% CI: 18.6, 78.8) with P=0.002, whereas the mean change in TSAT was lower with an estimated treatment effect of -4.4 (95% CI: -7.4, -1.4) with P=0.005, compared with patients treated with oral iron. No differences in changes of QoL were observed. The safety profile was similar between the groups. The proportion of responders with Hb ≥2 g/dl (IV group: 67%; oral group: 61%) were comparable between the groups (P=0.32). Iron isomaltoside 1,000 was more efficacious with higher cumulative doses of >1,000 mg IV. Significant predictors of Hb response to IV iron treatment were baseline Hb and C-reactive protein (CRP). CONCLUSIONS We could not demonstrate non-inferiority of IV iron isomaltoside 1,000 compared with oral iron in this study. Based on the dose-response relationship observed with the IV iron compound, we suggest that the true iron demand of IV iron was underestimated by the Ganzoni formula in our study. Alternative calculations including Hb and CRP should be explored to gauge iron stores in patients with IBD.
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Wolf M, Koch TA, Bregman DB. Effects of iron deficiency anemia and its treatment on fibroblast growth factor 23 and phosphate homeostasis in women. J Bone Miner Res 2013; 28:1793-803. [PMID: 23505057 DOI: 10.1002/jbmr.1923] [Citation(s) in RCA: 281] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 02/10/2013] [Accepted: 03/04/2013] [Indexed: 12/13/2022]
Abstract
Fibroblast growth factor 23 (FGF23) is an osteocyte-derived hormone that regulates phosphate and vitamin D homeostasis. Through unknown mechanisms, certain intravenous iron preparations induce acute, reversible increases in circulating FGF23 levels that lower serum phosphate in association with inappropriately low levels of calcitriol, similar to genetic diseases of primary FGF23 excess. In contrast, studies in wild-type mice suggest that iron deficiency stimulates fgf23 transcription but does not result in hypophosphatemia because FGF23 is cleaved within osteocytes by an unknown catabolic system. We tested the association of iron deficiency anemia with C-terminal FGF23 (cFGF23) and intact FGF23 (iFGF23) levels in 55 women with a history of heavy uterine bleeding, and assessed the longitudinal biochemical response over 35 days to equivalent doses of randomly-assigned, intravenous elemental iron in the form of ferric carboxymaltose (FCM) or iron dextran. Iron deficiency was associated with markedly elevated cFGF23 (807.8 ± 123.9 relative units [RU]/mL) but normal iFGF23 (28.5 ± 1.1 pg/mL) levels at baseline. Within 24 hours of iron administration, cFGF23 levels fell by approximately 80% in both groups. In contrast, iFGF23 transiently increased in the FCM group alone, and was followed by a transient, asymptomatic reduction in serum phosphate <2.0 mg/dL in 10 women in the FCM group compared to none in the iron dextran group. Reduced serum phosphate was accompanied by increased urinary fractional excretion of phosphate, decreased calcitriol levels, and increased parathyroid hormone levels. These findings suggest that iron deficiency increases cFGF23 levels, and that certain iron preparations temporarily increase iFGF23 levels. We propose that intravenous iron lowers cFGF23 in humans by reducing fgf23 transcription as it does in mice, whereas carbohydrate moieties in certain iron preparations may simultaneously inhibit FGF23 degradation in osteocytes leading to transient increases in iFGF23 and reduced serum phosphate.
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Affiliation(s)
- Myles Wolf
- Division of Nephrology and Hypertension, University of Miami Miller School of Medicine, Miami, FL 33136, USA.
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Prats M, Font R, García C, Cabré C, Jariod M, Vea AM. Effect of ferric carboxymaltose on serum phosphate and C-terminal FGF23 levels in non-dialysis chronic kidney disease patients: post-hoc analysis of a prospective study. BMC Nephrol 2013; 14:167. [PMID: 23902731 PMCID: PMC3751040 DOI: 10.1186/1471-2369-14-167] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 07/12/2013] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Some parenteral iron therapies have been found to be associated with hypophosphatemia. The mechanism of the decrease in serum phosphate is unknown. The aim of this study is to examine the effect of IV ferric carboxymaltose(FCM) on phosphate metabolism and FGF23 levels in patients with chronic kidney disease(CKD). METHODS This is a post-hoc analysis of a prospective study carried out in 47 non-dialysis CKD patients with iron-deficiency anaemia who received a single 1000 mg injection of FCM. Markers of mineral metabolism (calcium, phosphate, 1,25-dihydroxyvitamin D, PTH and FGF23[c-terminal]) were measured prior to FCM administration and at week 3 and week 12 after FCM administration. Based on the measured levels of serum phosphate at week 3, patiens were classified as hypophosphatemic or non-hypophosphatemic. RESULTS Serum phosphate levels decreased significantly three weeks after FCM administration and remained at lower levels at week 12 (4.24 ± 0.84 vs 3.69 ± 1.10 vs 3.83 ± 0.68 mg/dL, respectively, p < 0.0001. Serum calcium, PTH and 1,25-dihydroxyvitamin D did not change over the course of the study. Serum FGF23 decreased significantly from 442(44.9-4079.2) at baseline to 340(68.5-2603.3) at week 3 and 191.6(51.3-2465.9) RU/mL at week 12, p < 0.0001. Twelve patients were non-hypophosphatemic and 35 hypophosphatemic. FGF23 levels decreased in both groups, whereas no changes were documented in any of the other mineral parameters. CONCLUSIONS In non-dialysis CKD patients, FCM induces reduction in serum phosphate levels that persists for three months. FCM causes a significant decrease in FGF23 levels without changes to other bone metabolism parameters.
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Yamamoto S, Okada Y, Mori H, Kurozumi A, Torimoto K, Arao T, Tanaka Y. Iatrogenic osteomalacia: report of two cases. J UOEH 2013; 35:25-31. [PMID: 23475021 DOI: 10.7888/juoeh.35.25] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
UNLABELLED CASE 1: An 80-year-old man presented at our hospital with pain in both knees.He had received continuous intravenous administration of saccharated ferric oxide (SFO) over a period of five years following a diagnosis of iron-deficiency anemia.Blood tests revealed hypophosphatemia (1.4 mg/dl) and high circulating levels of fibroblast growth factor 23 (FGF23) at 248.8 mg/dl.These findings led to the diagnosis of FGF23-related osteomalacia due to SFO administration.Accordingly, the treatment plan was first to discontinue SFO, which led to a decrease in pain and normalization of phosphorus and FGF23 after 1 month.CASE 2: A 63-year-old woman presented at our hospital with leg pain.She had undergone total gastrectomy for gastric cancer at 36 years of age.Blood tests revealed hypocalcemia (8.3 mg/dl) and hypophosphatemia (2.2 mg/dl), and 25(OH)D at no more than 5 pg/ml.Bone X-rays showed significantly diminished bone shadowing.These findings led to a diagnosis of vitamin D-deficient osteomalacia due to impaired absorption following total gastrectomy.For therapy, she was treated with 1 μg/day oral alfacalcidol.Two months after initiating treatment, the pain improved. CONCLUSION When a patient is diagnosed with unexplained pain, it is important to pay attention to the possibility of an iatrogenic etiology.
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Affiliation(s)
- Sunao Yamamoto
- First Department of Internal Medicine, University of Occupational and Environmental Health, Japan
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Moore KLF, Kildahl-Andersen O, Kildahl-Andersen R, Tjønnfjord GE. Uvanlig bivirkning av et vanlig legemiddel. TIDSSKRIFT FOR DEN NORSKE LEGEFORENING 2013; 133:165. [DOI: 10.4045/tidsskr.12.0494] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
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Deger SM, Erten Y, Pasaoglu OT, Derici UB, Reis KA, Onec K, Pasaoglu H. The effects of iron on FGF23-mediated Ca-P metabolism in CKD patients. Clin Exp Nephrol 2012. [PMID: 23180041 DOI: 10.1007/s10157-012-0725-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Fibroblast growth factor 23 (FGF23) is an important counterregulatory hormone for phosphate homeostasis. Since it has been reported that iron administration induces hypophosphatemic osteomalacia by triggering FGF23 synthesis, we hypothesized that iron administration might lead to a further increase in FGF23, resulting in alterations to Ca-P metabolism in a stage 5 CKD population. METHODS This cross-sectional study was performed in a single center, and involved 73 hemodialysis patients (47.7 ± 15.74 years old, 68.5% men), 29 peritoneal dialysis patients (44.55 ± 15.05 years old, 62.1% men), and 55 healthy (43.57 ± 14.36 years old, 55.6% men) subjects. The dialysis group was subcategorized according to iron therapy administration into users and nonusers. RESULTS The median iFGF23 level was significantly higher in the dialysis population than in the healthy controls [88.050 (25.2-1038.3) pg/ml versus 46.95 (2.4-356) pg/ml (p < 0.001)]. In the dialysis population, a significantly lower median iFGF23 level was observed in iron therapy users than in nonusers [87.6 (25.2-1038.3) versus 119 (51.6-1031); respectively, p = 0.045]. A significant negative association between iron administration and iFGF23 level was revealed by both univariate (r = -0.237, p = 0.016) and multivariate (β = -0.221, p = 0.032) analysis. No association was found between iFGF23 and serum ferritin and iron levels. Also, there was no association between iron therapy and serum phosphate level. CONCLUSION In contrast to what is seen for the general population, this study showed that there was a negative relationship between iron administration and serum iFGF23 level in a dialysis population. We can therefore conclude that if high levels of FGF23 are harmful, iron therapy may have a beneficial effect on bone metabolism by reducing FGF23 levels in a dialysis population.
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Affiliation(s)
- Serpil Muge Deger
- Department of Internal Medicine, Department of Nephrology, Gazi University Faculty of Medicine, Besevler, Ankara, 06500, Turkey.
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Yamamoto S, Okada Y, Mori H, Fukumoto S, Tanaka Y. Fibroblast growth factor 23-related osteomalacia caused by the prolonged administration of saccharated ferric oxide. Intern Med 2012; 51:2375-8. [PMID: 22975552 DOI: 10.2169/internalmedicine.51.7450] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 44-year-old woman with iron deficiency anemia was on a continuous course of intravenous saccharated ferric oxide (SFO). She came to our hospital because of right hip joint pain. She was found to have hypophosphatemia caused by impaired phosphorus resorption and her fibroblast growth factor 23 (FGF-23) levels were elevated. Therefore, she was diagnosed with FGF-23-related osteomalacia due to SFO administration. Discontinuation of the SFO treatment rapidly improved the impaired phosphorus resorption and also normalized the blood levels of phosphorus and FGF-23. During the treatment with SFO, it is important to regularly measure the blood levels of phosphorus in order to prevent the occurrence of osteomalacia.
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Affiliation(s)
- Sunao Yamamoto
- The First Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Japan
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Iron deficiency drives an autosomal dominant hypophosphatemic rickets (ADHR) phenotype in fibroblast growth factor-23 (Fgf23) knock-in mice. Proc Natl Acad Sci U S A 2011; 108:E1146-55. [PMID: 22006328 DOI: 10.1073/pnas.1110905108] [Citation(s) in RCA: 261] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Autosomal dominant hypophosphatemic rickets (ADHR) is unique among the disorders involving Fibroblast growth factor 23 (FGF23) because individuals with R176Q/W and R179Q/W mutations in the FGF23 (176)RXXR(179)/S(180) proteolytic cleavage motif can cycle from unaffected status to delayed onset of disease. This onset may occur in physiological states associated with iron deficiency, including puberty and pregnancy. To test the role of iron status in development of the ADHR phenotype, WT and R176Q-Fgf23 knock-in (ADHR) mice were placed on control or low-iron diets. Both the WT and ADHR mice receiving low-iron diet had significantly elevated bone Fgf23 mRNA. WT mice on a low-iron diet maintained normal serum intact Fgf23 and phosphate metabolism, with elevated serum C-terminal Fgf23 fragments. In contrast, the ADHR mice on the low-iron diet had elevated intact and C-terminal Fgf23 with hypophosphatemic osteomalacia. We used in vitro iron chelation to isolate the effects of iron deficiency on Fgf23 expression. We found that iron chelation in vitro resulted in a significant increase in Fgf23 mRNA that was dependent upon Mapk. Thus, unlike other syndromes of elevated FGF23, our findings support the concept that late-onset ADHR is the product of gene-environment interactions whereby the combined presence of an Fgf23-stabilizing mutation and iron deficiency can lead to ADHR.
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Wada Y, Kinoshita Y, Taguchi M, Fukumoto S, Fujita T. [Case report; A case of FGF23-related hypophosphatemic osteomalacia caused by long-term administration of saccharated ferric oxide]. NIHON NAIKA GAKKAI ZASSHI. THE JOURNAL OF THE JAPANESE SOCIETY OF INTERNAL MEDICINE 2011; 100:3031-3033. [PMID: 22175146 DOI: 10.2169/naika.100.3031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Affiliation(s)
- Yumie Wada
- Division of Nephrology & Endocrinology, Department of Medicine, The University of Tokyo Hospital, Japan
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Takeda Y, Komaba H, Goto S, Fujii H, Umezu M, Hasegawa H, Fujimori A, Nishioka M, Nishi S, Fukagawa M. Effect of intravenous saccharated ferric oxide on serum FGF23 and mineral metabolism in hemodialysis patients. Am J Nephrol 2011; 33:421-6. [PMID: 21502756 DOI: 10.1159/000327019] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Accepted: 03/02/2011] [Indexed: 12/20/2022]
Abstract
BACKGROUND/AIMS Fibroblast growth factor-23 (FGF23) plays a central role in the development of hypophosphatemia and inappropriately low 1,25-dihydroxyvitamin D induced by iron therapy for iron-deficiency anemia. The aim of this study was to examine the effect of intravenous saccharated ferric oxide on serum FGF23 levels and mineral metabolism in hemodialysis patients. METHODS This prospective study enrolled 27 hemodialysis patients who had iron-deficiency anemia defined by a hemoglobin concentration < 10.5 g/dl and serum ferritin < 100 ng/ml. Intravenous saccharated ferric oxide at a dose of 40 mg was administered three times weekly over 3 weeks. The dose of active vitamin D and phosphate binders was kept unchanged. Serum FGF23, intact parathyroid hormone (PTH) and other parameters were prospectively monitored for 5 weeks. RESULTS Serum FGF23 levels were markedly elevated [3,453 (338-6,383) pg/ml] at baseline. After 3 weeks of intravenous saccharated ferric oxide treatment, serum FGF23 further increased to 4,701 (1,251-14,396) pg/ml, and returned to the baseline values after 2 weeks of observation. There was also a significant decrease in intact PTH but no changes in serum calcium and phosphorus. CONCLUSIONS Intravenous saccharated ferric oxide induces further increase in elevated FGF23 levels in hemodialysis patients. This increase does not induce hypophosphatemia and inappropriately low 1,25-dihydroxyvitamin D in the absence of functioning kidney, but may result in transient PTH suppression - possibly by directly acting on the parathyroid.
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Affiliation(s)
- Yoko Takeda
- Division of Nephrology and Kidney Center, Kobe University Graduate School of Medicine, Kobe, Japan
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Neven E, De Schutter TM, Behets GJ, Gupta A, D'Haese PC. Iron and vascular calcification. Is there a link? Nephrol Dial Transplant 2011; 26:1137-45. [PMID: 21325349 DOI: 10.1093/ndt/gfq858] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Iron deficiency is frequently seen in patients with end-stage renal disease, particularly in those treated by dialysis, this is because of an impairment in gastrointestinal absorption and ongoing blood losses or alternatively, due to an impaired capacity to mobilize iron from its stores, called functional iron deficiency. Therefore, these patients may require intravenous iron to sustain adequate treatment with erythropoietin-stimulating agents. Aside from this, they are also prone to vascular calcification, which has been reported a major contributing factor in the development of cardiovascular disease and the increased mortality associated herewith. Several factors and mechanisms underlying the development of vascular calcification in chronic kidney diseased patients have been put forward during recent years. In view of the ability of iron to exert direct toxic effects and to induce oxidative stress on the one hand versus its essential role in various cellular processes on the other hand, the possible role of iron in the development of vascular calcification should be considered.
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Affiliation(s)
- Ellen Neven
- Laboratory of Pathophysiology, Faculties of Medicine and Pharmaceutical, Biomedical and Veterinary Sciences, University of Antwerp, Wilrijk, Belgium
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Holick MF. Osteomalacia and rickets. Rheumatology (Oxford) 2011. [DOI: 10.1016/b978-0-323-06551-1.00199-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Abstract
Hypophosphatemia (serum phosphorus concentration <2.5 mg/dl, 0.8 mmol/l), although rare in the general population, is commonly observed in hospitalized patients and may be associated with drug therapy. In fact, hypophosphatemia frequently develops in the course of treatment with drugs used in every-day clinical practice including diuretics and bisphosphonates. Proper diagnostic approach of patients with low serum phosphorus concentrations should involve a detailed medical history with special attention to the recent use of medications. The clinical manifestations of drug-induced hypophosphatemia are usually mild but might also be severe and potentially life-threatening. This review aims at a thorough understanding of the underlying pathophysiological mechanisms and risk factors of drug therapy-related hypophosphatemia thus allowing prevention and effective intervention strategies.
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Affiliation(s)
- G Liamis
- Department of Internal Medicine, School of Medicine, University of Ioannina, 45110 Ioannina, Greece
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Aranami F, Segawa H, Furutani J, Kuwahara S, Tominaga R, Hanabusa E, Tatsumi S, Kido S, Ito M, Miyamoto KI. Fibroblast growth factor 23 mediates the phosphaturic actions of cadmium. THE JOURNAL OF MEDICAL INVESTIGATION 2010; 57:95-108. [PMID: 20299748 DOI: 10.2152/jmi.57.95] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
Phosphaturia has been documented following cadmium (Cd) exposure in both humans and experimental animals. The fibroblast growth factor 23 (FGF23)/klotho axis serves as an essential phosphate homeostasis pathway in the bone-kidney axis. In the present study, we investigated the effects of Cd on phosphate (Pi) homeostasis in mice. Following Cd injection into WT mice, plasma FGF23 concentration was significantly increased. Urinary Pi excretion levels were significantly higher in Cd-injected WT mice than in control group. Plasma Pi concentration decreased only slightly compared with control group. No change was observed in plasma parathyroid hormone and 1,25-dihydroxy vitamin D(3) in both group of mice. We observed a decrease in phosphate transport activity and also decrease in expression of renal phosphate transporter SLC34A3 [NaPi-IIc/NPT2c], but not SLC34A1 [NaPi-IIa/NPT2a]. Furthermore, we examined the effect of Cd on Npt2c in Npt2a-knockout (KO) mice which expresses Npt2c as a major NaPi co-transporter. Injecting Cd to Npt2aKO mice induced significant increase in plasma FGF23 concentration and urinary Pi excretion levels. Furthermore, we observed a decrease in phosphate transport activity and renal Npt2c expression in Cd-injected Npt2a KO mice. The present study suggests that hypophosphatemia induced by Cd may be closely associated with the FGF23/klotho axis.
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Affiliation(s)
- Fumito Aranami
- Deprtment of Molecular Nutrition, Institution of Health Biosciences, University of Tokushima Graduate School, Tokushima, Japan
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Abstract
Phosphate is critical for the maintenance of skeletal integrity, is a necessary component of important biomolecules, and is central to signal transduction and cell metabolism. It is becoming clear that endocrine communication between the skeleton, kidney, and the intestine is involved in maintaining appropriate serum phosphate concentrations, and that the kidney is the primary site for minute-to-minute regulation of phosphate levels. The identification of genetic alterations in Mendelian disorders of hypophosphatemia and hyperphosphatemia has led to the isolation of novel genes and the identification of new roles for existing proteins--such as fibroblast growth factor 23 and its processing systems, the co-receptor alpha-klotho, and phosphate transporters--in the control of renal phosphate handling. Recent findings also indicate that fibroblast growth factor 23 has feedback mechanisms involving parathyroid hormone and vitamin D that control phosphate homeostasis. This Review will highlight genetic, in vitro and in vivo findings, and will discuss how these clinical and experimental discoveries have uncovered novel aspects of renal phosphate handling and opened new research and therapeutic avenues.
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Shimizu Y, Tada Y, Yamauchi M, Okamoto T, Suzuki H, Ito N, Fukumoto S, Sugimoto T, Fujita T. Hypophosphatemia induced by intravenous administration of saccharated ferric oxide: another form of FGF23-related hypophosphatemia. Bone 2009; 45:814-6. [PMID: 19555782 DOI: 10.1016/j.bone.2009.06.017] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Accepted: 06/16/2009] [Indexed: 11/15/2022]
Abstract
Fibroblast growth factor 23 (FGF23) is a humoral factor that is produced by osteocytes and regulates phosphate and vitamin D metabolism. Several hypophosphatemic diseases including X-linked, autosomal dominant and autosomal recessive hypophosphatemic rickets/osteomalacia and tumor-induced rickets/osteomalacia are caused by excess actions of FGF23. These diseases are characterized by hypophosphatemia associated with impaired proximal tubular phosphate reabsorption and inappropriately low serum 1,25-dihydroxyvitamin D [1,25(OH)(2)D] levels for hypophosphatemia. Saccharated ferric oxide is widely used in Japan for iron-deficiency anemia. While it has been shown that saccharated ferric oxide induces hypophosphatemic osteomalacia, the mechanism of this hypophosphatemia remains to be clarified. We here describe three hypophosphatemic patients caused by intravenous administration of saccharated ferric oxide. Hypophosphatemia in these patients were associated with impaired renal tubular phosphate reabsorption, rather low serum 1,25(OH)(2)D and high FGF23 levels. All these biochemical features improved by the cessation of saccharated ferric oxide. These results indicate that hypophosphatemia caused by saccharated ferric oxide is another form of FGF23-related hypophosphatemia.
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Affiliation(s)
- Yuichiro Shimizu
- Division of Nephrology and Endocrinology, Department of Medicine, The University of Tokyo Hospital, Tokyo, Japan
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Schouten BJ, Hunt PJ, Livesey JH, Frampton CM, Soule SG. FGF23 elevation and hypophosphatemia after intravenous iron polymaltose: a prospective study. J Clin Endocrinol Metab 2009; 94:2332-7. [PMID: 19366850 DOI: 10.1210/jc.2008-2396] [Citation(s) in RCA: 160] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
CONTEXT Parenteral iron administration has been associated with hypophosphatemia. Fibroblast growth factor 23 (FGF23) has a physiological role in phosphate homeostasis via suppression of 25-hydroxyvitamin D [25(OH)D] activation and promotion of phosphaturia. We recently reported a case of iron-induced hypophosphatemic osteomalacia associated with marked FGF23 elevation. OBJECTIVE Our objective was to prospectively investigate the effect of parenteral iron polymaltose on phosphate homeostasis and to determine whether any observed change was related to alterations in circulating FGF23. DESIGN, SETTING, AND PARTICIPANTS Eight medical outpatients prescribed iv iron polymaltose were recruited. Plasma phosphate, 25(OH)D, 1,25-dihydroxyvitamin D [1,25(OH)(2)D], PTH, FGF23, and urinary tubular reabsorption of phosphate were measured prior to iron administration and then weekly for a minimum of 3 wk. RESULTS Plasma phosphate fell from 3.4 +/- 0.6 mg/dl at baseline to 1.8 +/- 0.6 mg/dl at wk 1 (P < 0.0001) associated with a fall in percentage tubular reabsorption of phosphate (90 +/- 4.8 to 68 +/- 13; P < 0.001) and 1,25(OH)(2)D (54 +/- 25 to 9 +/- 8 pg/ml; P < 0.001). These indices remained significantly suppressed at wk 2 and 3. 25(OH)D levels were unchanged. FGF23 increased significantly from 43.5 pg/ml at baseline to 177 pg/ml at wk 1 (P < 0.001) with levels correlating with both serum phosphate (R = -0.74; P <0.05) and 1,25(OH)(2)D (R = -0.71; P < 0.05). CONCLUSION Parenteral iron suppresses renal tubular phosphate reabsorption and 1alpha-hydroxylation of vitamin D resulting in hypophosphatemia. Our data suggest that this is mediated by an increase in FGF23.
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Affiliation(s)
- Belinda J Schouten
- Department of Endocrinology, Christchurch Hospital, Christchurch, New Zealand.
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Schouten BJ, Doogue MP, Soule SG, Hunt PJ. Iron polymaltose-induced FGF23 elevation complicated by hypophosphataemic osteomalacia. Ann Clin Biochem 2009; 46:167-9. [PMID: 19151167 DOI: 10.1258/acb.2008.008151] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Iron-induced renal phosphate wasting, hypophosphataemia and osteomalacia have previously been reported in a small number of Japanese patients receiving parenteral iron sucrose. We report the case history of a European male who, as a result of regular intravenous iron polymaltose, developed prolonged hypophosphataemia complicated by widespread insufficiency fractures. The pathogenesis of this complication remains unknown however our novel finding of a marked elevation in fibroblast growth factor 23 (FGF23), which normalized after ceasing parenteral iron, suggests an important and previously unreported effect of iron on FGF23 homeostasis.
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Affiliation(s)
- Belinda J Schouten
- Department of Endocrinology, Christchurch Public Hospital, Christchurch, New Zealand.
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Iron, oxidative stress, and clinical outcomes. Pediatr Nephrol 2008; 23:1195-9. [PMID: 18030498 DOI: 10.1007/s00467-007-0673-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2007] [Revised: 10/04/2007] [Accepted: 10/08/2007] [Indexed: 11/27/2022]
Abstract
It is well known that iron is pro-oxidant. Chronic kidney disease (CKD) is a pro-oxidant state, and intravenous administration of iron is frequently used to correct anemia. On one hand, there is little doubt that iron causes oxidative stress. On the other, it is far from clear whether oxidative stress, so generated, leads to poor clinical outcomes. Iron has benefits that may be independent of the correction of anemia. Furthermore, concerns surround the use of high doses of erythropoietin in causing excess heart failure and death in patients with CKD. Thus, it would be prudent if iron were to continue to be used judiciously in patients who require erythropoietin. Iron, given orally, would be the preferred first-line agent in patients not on hemodialysis. In patients with sepsis, intravenous treatment with iron should be avoided, because, in animal experiments, intravenous administration of iron can compound the inflammatory response and increase mortality. Clinical trials are needed to ascertain the risk and benefits of the intravenous administration of iron in patients with CKD.
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Tanimoto K, Okubo Y, Harada C, Saito H, Sata A, Nishikawa A, Ohwada R, Tsuiki M, Yamamoto M, Hashimoto E, Sato K, Takano K. Latent hypoparathyroidism in an osteoporotic patient with multiple endocrinopathies and secondary hemochromatosis due to multiple blood transfusions, unmasked by alendronate and glucocorticoid at adrenal crisis. Intern Med 2008; 47:515-20. [PMID: 18344638 DOI: 10.2169/internalmedicine.47.0642] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A 30-year-old normocalcemic man with hypopituitarism, hypogonadism, diabetes mellitus, and secondary hemochromatosis due to multiple blood transfusions was admitted because of adrenal crisis. After intravenous administration of saline and cortisol, the corrected serum level of calcium decreased to 7.3 mg/dl. This osteoporotic patient had been prescribed alendronate for radial bone fracture. Since the increase in intact PTH (68 pg/ml) was impaired compared to that seen in hypocalcemic patients with secondary hyperparathyroidism, we presume that the patient has had latent hypoparathyroidism, which was unmasked by the administration of glucocorticoid and bisphosphonate. With a supplemented dose of 1alpha-OHD3, the patient has been eucalcemic.
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Affiliation(s)
- Keiji Tanimoto
- Department of Medicine, Institute of Clinical Endocrinology, Tokyo Women's Medical University
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Michael B, Fishbane S, Coyne DW, Agarwal R, Warnock DG. Drug Insight: safety of intravenous iron supplementation with sodium ferric gluconate complex. ACTA ACUST UNITED AC 2006; 2:92-100. [PMID: 16932400 DOI: 10.1038/ncpneph0068] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2005] [Accepted: 10/03/2005] [Indexed: 11/09/2022]
Abstract
Intravenous iron is necessary for optimal management of anemia in patients receiving hemodialysis and is utilized in the majority of these patients in the US. The availability of nondextran formulations of intravenous iron has significantly improved the safety of its use. The nondextran iron formulation sodium ferric gluconate complex (SFGC) has been extensively studied in the hemodialysis population, with two large phase IV trials documenting its safety. SFGC is efficacious and, at recommended doses, is associated with a low incidence of adverse events. There have been few comparative studies of the nondextran intravenous iron preparations; however, they are known to have different pharmacokinetic characteristics. There is also evidence to indicate that these compounds differ in terms of their cytotoxic and proinflammatory properties, and their propensity to induce oxidative stress. This paper reviews the current literature on the safety of SFGC and examines the emerging safety issues surrounding the use of intravenous iron.
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Affiliation(s)
- Beckie Michael
- Thomas Jefferson University, Philadelphia, PA 19107, USA.
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Fishbane S. Opinion: How Should Chronic Medical Therapies be Altered with the Onset of End-Stage Renal Disease and Initiation of Dialysis? Semin Dial 2006. [DOI: 10.1111/j.1525-139x.2006.00112.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Agarwal R, Vasavada N, Sachs NG, Chase S. Oxidative stress and renal injury with intravenous iron in patients with chronic kidney disease. Kidney Int 2004; 65:2279-89. [PMID: 15149341 DOI: 10.1111/j.1523-1755.2004.00648.x] [Citation(s) in RCA: 193] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Intravenous iron is widely prescribed in patients with chronic kidney disease (CKD) and can cause oxidative stress. The relationship of oxidative stress and renal injury in patients with CKD is unknown. Whether renal injury can occur at a time point when transferrin is incompletely saturated is also unclear. METHODS We conducted a randomized, open-label, parallel group trial to compare the oxidative stress induced by intravenous administration of 100 mg iron sucrose over 5 minutes and its protection with N-acetylcysteine (NAC) in 20 subjects with stage 3 or 4 CKD. Transferrin saturation was measured with urea polyacrylamide gel electrophoresis, oxidative stress by malondialdehyde (MDA) measurement by high-performance liquid chromatography, and renal injury by enzymuria and proteinuria. Reduced and oxidized glutathione and free radical scavengers as well as urinary monocyte chemoattractant protein-1 were also measured. RESULTS Parenteral iron increased plasma concentration and urinary excretion rate of MDA, a biomarker of lipid peroxidation, within 15 to 30 minutes of iron sucrose administration. This was accompanied by enzymuria and increase in proteinuria. In contrast, saturation of transferrin was not maximally seen until 3 hours after the end of infusion. Oxidative stress, enzymuria and proteinuria were transient and were completely resolved in 24 hours. NAC reduced acute generation of systemic oxidative stress but failed to abrogate proteinuria or enzymuria. CONCLUSION Intravenous iron produces oxidative stress that is associated with transient proteinuria and tubular damage. The rapid production of oxidative stress even when transferrin is not completely saturation suggests free iron independent mechanism(s) to be operative in producing oxidative stress and transient renal injury. Long-term implications of these findings need further study.
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Affiliation(s)
- Rajiv Agarwal
- Division of Nephrology, Department of Medicine, Indiana University School of Medicine, and Richard L. Roudebush VA Medical Center, Indianapolis, 46202, USA.
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