[Evaluation of serum iron as a predictor of a hemoglobin response to injectable iron treatment in chronic hemodialysis patients]. / Évaluation du fer sérique comme facteur prédictif d'une réponse de l'hémoglobine au traitement par fer injectable chez les patients hémodialysés chroniques.

BACKGROUND: The detection and correction of iron deficiency are essential for the treatment of anemia in chronic hemodialysis patients. The aim of our study was to assess the ability of serum iron to predict hemoglobin response to intravenous iron supplementation in hemodialysis patients. METHODS: It is a retrospective study in 91 hemodialysis patients during 2016 at Clermont-Ferrand University Hospital for whom intravenous iron supplementation had been started. A responder patient was defined as an increase in hemoglobin greater than or equal to 1 g/dL/month and/or a decrease in the dose of erythropoiesis stimulating agent after two months of iron supplementation. RESULTS: In responding patients, serum iron was significantly lower (6.7 ± 2.7 µmol/L) compared to non-responding patients (8.9±2.9 µmol/L; P<0.001). The positive response to iron supplementation was significantly associated with low serum iron (odds ratio = 0.58 [0.42-0.81]; P=0.002) in a logistic regression model taking into account ferritin, transferrin saturation coefficient, dose variation monthly iron and erythropoiesis stimulating agent and the duration of dialysis. The area under the receiver operating characteristic curve of serum iron, ferritin and transferrin saturation coefficient to predict the response to iron supplementation were 0.72, 0.51 and 0.64, respectively (serum iron versus ferritin [P=0.006] and serum iron versus transferrin saturation coefficient [P=0.04]). The sensitivity for serum iron below 7.5 µmol/L was better than that for ferritin below 86 ng/mL (P<0.001) and the specificity for serum iron below 7.5 µmol/L was better than that for TSC less than 19% (P=0.02). CONCLUSION: Serum iron below 7.5 µmol/L can predict the success of the response to iron supplementation in chronic hemodialysis patients.

Therapeutic use of transferrin to modulate anemia and conditions of iron toxicity.

As the main iron transporter, transferrin delivers iron to target tissues like the bone marrow for erythropoiesis. Also, by binding free iron, transferrin prevents formation of reactive oxygen species. Transferrin deficiency due to congenital hypotransferrinemia is characterized by anemia as well as oxidative stress related to toxic free iron. Transferrin supplementation may be beneficial in two ways. First, transferrin can correct anemia by modulating the amount of iron that is available for erythropoiesis. This is obvious for patients that suffer from hypotransferrinemia, but may also have beneficial effects for ß-thalassemia patients. Second, under conditions of iron overload, transferrin reduces oxidative stress by binding free iron in the circulation and in tissues. Hereby, transferrin protects the host against the reactive oxygen species that can be formed as a consequence of free iron. This beneficial effect is shown in hematological patients undergoing chemotherapy and stem cell transplantation. Transferrin may also be beneficial in lung injury, ischemia-reperfusion injury and hypomyelination. This review summarizes the preclinical and clinical data on the efficacy of exogenous transferrin administration to modulate certain forms of anemia and to prevent the toxic effects of free iron. Thereby, we show that transferrin has promising therapeutic potential in a wide variety of conditions.

Iron deficiency in patients with solid tumours: prevalence and management in clinical practice

PURPOSE: The objective of the present study was to describe the prevalence and management of anaemia and iron deficiency (ID) in treatment-naïve patients with solid tumours in Spain and the incidence of anaemia over 4 months of cancer treatment in clinical practice. METHODS: Multicentre, prospective and observational study in newly diagnosed cancer patients. Data on anaemia and iron parameters and its management were collected prior to the initiation of chemotherapy, at each cycle of chemotherapy and after 4 months of treatment. The main outcomes of the study were the prevalence of anaemia at baseline, its incidence during cancer treatment and the prevalence of absolute ID (AID) and functional ID (FID) prior to chemotherapy initiation. RESULTS: A total of 295 patients were included in the study. Anaemia was present at diagnosis in 38.6 % of patients and was treated only in 32.5 % of those. A total of 106 patients (60.2 %) without anaemia at baseline developed anaemia during cancer treatment. Serum ferritin and transferrin saturation data were available for 151 of the patients (51.2 %) included in the study. The overall prevalence of ID was 59 %: 48 patients (31.8 %) presented with AID and 41 patients (27.2 %) presented with FID before starting anti-cancer therapy. Thirty-three of 44 non-anaemic iron-deficient patients did not receive any type of iron supplementation before initiating cancer therapy. CONCLUSIONS: Iron parameters are not commonly measured in newly diagnosed cancer patients. A correct evaluation and early management of ID could reduce the incidence of treatment-related anaemia in cancer patients (AU)

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Iron overload, hematopoietic cell transplantation, and graft-versus-host disease.

Many patients who undergo hematopoietic cell transplantation (HCT) present with anemia and have received red blood cell transfusions before HCT. As a result, iron overload is frequent and appears to be particularly prominent in patients with myelodysplastic syndromes. There is evidence that peritransplant events contribute to further iron accumulation, although the mechanism that disrupts normal iron homeostasis remains to be determined. Recent studies suggest that iron overload, as determined by ferritin levels, a surrogate marker for iron, is a risk factor for increased non-relapse mortality after HCT. Iron overload is associated with an increased rate of infections, in particular with fungal organisms. Furthermore anecdotal data suggest that increased hepatic iron may mimic the clinical picture of (chronic) graft-versus-host-disease (GVHD). Whether excess iron contributes to GVHD and whether iron depletion, be it by phlebotomy or chelation, reduces the post-transplantation complication rate and improves transplant outcome is yet to be determined.

The anti-malaria drug artesunate inhibits replication of cytomegalovirus in vitro and in vivo.

Treatment of human cytomegalovirus (HCMV) infections with any of the currently available antiviral agents is frequently associated with the occurrence of severe complications, seriously threatening the successful outcome of treatment. Therefore, the development of novel antiviral strategies is a challenging goal of current investigations. Previously, we reported that artesunate (ART) is an effective, non-cytotoxic inhibitor of HCMV in vitro. Here, we demonstrate that the efficacy of the antiviral effect of ART is augmented by co-treatment of HCMV-infected fibroblasts with ferrous iron, i.e. Ferrosanol, and/or the iron transfer-mediating molecule holo-transferrin. This could alleviate the HCMV-induced modulation of cell surface expression of adhesion molecule Thy-1, suggesting that ART might be able to prevent pro-inflammatory effects of infection. The iron-enhanced, antiviral effect of ART could also be demonstrated in cultured cells infected with rat cytomegalovirus. Experiments using the RCMV/rat model showed that both the viral DNA load and virus titers in the salivary glands from infected rats were significantly reduced upon treatment with ART. Furthermore, an additive antiviral effect for ART together with each one of conventional anti-HCMV drugs, i.e. ganciclovir, cidofovir or foscarnet, was detected in HCMV-infected fibroblasts. These findings might open new perspectives regarding the use of ART in clinical trials.

Development of a pharmaceutical apotransferrin product for iron binding therapy.

High-dose chemotherapy of patients with haematological malignancies results in extracellular iron accumulation and appearance of non-transferrin-bound iron, which is thought to predispose the patients to septic infections and contribute to organ toxicity. We describe the development of a human plasma-derived apotransferrin product for iron binding therapy. The product is purified from Cohn fraction IV of human plasma by two ion exchange chromatography steps and ultrafiltration. The process comprises solvent detergent treatment as the main virus inactivation step and 15 nm virus filtration and polyethylene glycol precipitation as removal steps for physico-chemically resistant infectious agents. Product characterization by electrospray and MALDI-TOF mass spectrometry indicated no other chemical modifications than N-linked glycan chains and disulphide bonds, except minor oxidation. The purity of the product was more than 98%, main impurities being IgG, IgA and hemopexin. The product had intact iron binding capacity and native conformation. A stable liquid formulation for the finished product was developed. The product has proved safe and well tolerated in early clinical trials in iron binding therapy.

Alteration in the organ distribution of iron by truncated transferrin: implications for iron chelation therapy.

The ability of the partial molecule of transferrin, truncated transferrin (t-Tf), to act as an excretable biologic iron chelator was examined. We confirmed the observations of Zak and Aisen (Zak O, Aisen P. Biochem Biophys Acta 1985;1952:24-8) that thermolysin treatment of human transferrin produces half molecules that retain iron-binding capacity. These molecules are poorly recognized by surface receptors on either human or murine cells. Although the plasma half-life of human transferrin in mice is moderately long (40 hours), injection of t-Tf into mice results in its rapid clearance (half-life = 10 minutes). Injection of iron 59-labeled transferrin results in the deposition of iron in the major hematopoetic organs of mice such as the spleen, bone marrow, and liver. Injection of 59Fe-labeled t-Tf results in the quantitative recovery of iron in the kidneys: 59Fe is retained in the kidney for substantial periods of time with little evidence of its excretion into urine. Injection of iodine 125-labeled t-Tf also results in the deposition of radioactivity in the kidneys, but 125I is rapidly excreted into the urine, where it is detected as free iodine. These results indicate that although t-Tf is directed to the kidney and filtered by the glomerulus, the molecule is reabsorbed and degraded, and iron is retained. These results have implications in the design of iron chelators.

Estusio de los valores de hemoglobina, hierro sérico, transferrina, proteínas totales y fraccionadas y su relación con el estado nutricional en niños con neumonía / Study of the valors of hemoglobin silken iron, transferrin, proteins totals and fractionals and its relations with the state nutritional in the children with pneumonia

Se realizó un estudio descriptivo prospectivo para explorar las modificaciones en parámetros bioquímicos durante la fase aguda y de convalecencia en niños con Neumonía y la relevancia del estado nutricional en el proceso infeccioso. Se estudiaron 51 niños (1 a 6 años de edad) que ingresaron al Hospital Pediátrico "Dr. Elías Toro", en el período abril 1994-febrero 1995, con diagnóstico de neumonía según criterios IRA-OMS. Los niños se clasificaron nutricionalmente empleando indicadores antropométricos OMS. Se determinó al ingreso y egreso; concentración de Hemoglobina (Hb), hierro sérico (Fe), capacidad total de enlazamiento de hierro por la Transferrina (TIBC), proteínas séricas totales y fraccionadas. Al ingreso 73.6 por ciento de los niños poseía valores de Hb menores a 10 g/dL, 98 por ciento presentaron Fe menor al 11 µmol/L. Los valores TIBC de todos los niños estaban en el rango de referencia tanto al ingreso como al egreso. No se encontraron diferencias estadísticamente significativas en las concentraciones de proteínas séricas totales respecto a la condición nutricional. La variación en la fracción proteica Alfa-1, observada al ingreso respecto al egreso, mostró diferencia estadística en los grupos de nutridos y desnutridos agudos. El proceso infeccioso pareciera modular los cambios bioquímicos descritos en el grupo de niños nutridos y desnutridos leves incluidos en el presente estudio

Protective effect of exogenous transferrin against hyperoxia: a study on premature rabbits.

We hypothesized that an increase in plasma iron binding capacity would decrease the generation of oxygen radicals and of lipid peroxides. To test this hypothesis, we studied whether supplementation of transferrin (TF) in premature rabbits would modify the degree of hyperoxic lung injury. Animals, delivered prematurely at 29 days of gestation (term 31 days), were randomized and given either 0.5 g/kg of albumin (Alb) (n = 116) or 0.5 g/kg of iron-free TF (n = 132) intravenously within 2 hours after birth. Another group was randomized to receive saline (n = 15), or either 0.35 g/kg (n = 12) or 0.70 g/kg of iron-free TF (n = 8). After exposure to a 100% oxygen environment for 2 or 4 days, the animals were killed, and plasma and bronchoalveolar lavage (BAL) fluid was recovered. Infusion of TF caused a dose-dependent increase in the concentration of TF and an increase in the unsaturated iron-binding capacity. Administration of TF at birth increased the gradient of TF between serum and alveolar epithelial lining fluid on day 4, suggesting decreased alveolar-capillary permeability. BAL fluid and plasma from TF-supplemented animals contained less lipid peroxidation products and more inhibitor of lipid peroxidation than BAL fluid or plasma from Alb-treated animals. In TF-treated animals, the recovery of protein in BAL fluid (TF group, 1.26 +/- 0.07 mg; Alb group, 1.78 +/- 0.10 mg; P = 0.02) and the water content of the extravascular lung tissue (TF group, 78.5 +/- 1.4%; Alb group, 83.2 +/- 1.3%; P = 0.05) were lower than in Alb-treated animals. We propose that supplementation of iron-free TF decreases iron-catalyzed redox reactions and may decrease hyperoxic lung injury in the premature.