ferric-oxide--saccharated and ferric-hydroxide

Iron deficiency often occurs in patients with chronic kidney disease and can be effectively treated with parenteral supplementation of iron. In these patients, prompt application of iron therapy can help to reduce the dependence of erythropoietin-stimulating agents and effectively treat anemia. Correct evaluation of iron metabolism in CKD patients can be difficult. Duration of and response to therapy should always be considered while planning parenteral supplementation of iron. The main safety aspects of parenteral iron preparations relate to their possible anaphylactic potential and the potential induction of oxidative stress due to the release of free iron. However, parenteral iron supplementation is usually safe and without major side effects. Regarding current data, none of the iron preparations is showing definitive superiority. Although uncommon, iron preparations containing dextran can lead to severe side effects, therefore these preparations appear to have an inferior safety profile. Due to limited data, a comparison of third-generation iron preparations with previous preparations is not possible. Recently, for the first time, the third generation iron preparation ferumoxytol has been directly compared to iron sucrose. From this data and others, it remains unclear whether third generation iron preparations show safety-relevant superiority.

Topics: Administration, Oral; Anaphylaxis; Anemia, Iron-Deficiency; Disaccharides; Ferric Compounds; Ferric Oxide, Saccharated; Ferrosoferric Oxide; Glucaric Acid; Humans; Infusions, Intravenous; Iron Compounds; Iron-Dextran Complex; Kidney Failure, Chronic; Maltose; Oxidative Stress; Renal Dialysis

Hypoxia is a major cause of pulmonary hypertension in respiratory disease and at high altitude. Recent work has established that the effect of hypoxia on pulmonary arterial pressure may depend on iron status, possibly acting through the transcription factor hypoxia-inducible factor, but the pathophysiological and clinical importance of this interaction is unknown.. To determine whether increasing or decreasing iron availability modifies altitude-induced hypoxic pulmonary hypertension.. Two randomized, double-blind, placebo-controlled protocols conducted in October-November 2008. In the first protocol, 22 healthy sea-level resident men (aged 19-60 years) were studied over 1 week of hypoxia at Cerro de Pasco, Peru (altitude 4340 m). In the second protocol, 11 high-altitude resident men (aged 30-59 years) diagnosed with chronic mountain sickness were studied over 1 month of hypoxia at Cerro de Pasco, Peru.. In the first protocol, participants received intravenous infusions of Fe(III)-hydroxide sucrose (200 mg) or placebo on the third day of hypoxia. In the second protocol, patients underwent staged isovolemic venesection of 2 L of blood. Two weeks later, patients received intravenous infusions of Fe(III)-hydroxide sucrose (400 mg) or placebo, which were subsequently crossed over.. Effect of varying iron availability on pulmonary artery systolic pressure (PASP) assessed by Doppler echocardiography.. In the sea-level resident protocol, approximately 40% of the pulmonary hypertensive response to hypoxia was reversed by infusion of iron, which reduced PASP by 6 mm Hg (95% confidence interval [CI], 4-8 mm Hg), from 37 mm Hg (95% CI, 34-40 mm Hg) to 31 mm Hg (95% CI, 29-33 mm Hg; P = .01). In the chronic mountain sickness protocol, progressive iron deficiency induced by venesection was associated with an approximately 25% increase in PASP of 9 mm Hg (95% CI, 4-14 mm Hg), from 37 mm Hg (95% CI, 30-44 mm Hg) to 46 mm Hg (95% CI, 40-52 mm Hg; P = .003). During the subsequent crossover period, no acute effect of iron replacement on PASP was detected.. Hypoxic pulmonary hypertension may be attenuated by iron supplementation and exacerbated by iron depletion.. clinicaltrials.gov Identifier: NCT00952302.

Topics: Adult; Altitude; Altitude Sickness; Blood Pressure; Cross-Over Studies; Double-Blind Method; Echocardiography, Doppler; Ferric Compounds; Ferric Oxide, Saccharated; Glucaric Acid; Humans; Hypertension, Pulmonary; Hypoxia; Iron Deficiencies; Male; Middle Aged; Phlebotomy; Pulmonary Artery; Systole; Young Adult

Phosphate binders that contain aluminum or calcium are frequently prescribed to treat hyperphosphatemia in patients with end-stage renal disease (ESRD), but an accumulation of aluminum can lead to encephalopathy, aluminum-related bone disease (ARBD) such as osteomalacia, anaemia, and resistance to erythropoietin, and calcium accumulation can lead to hypercalcaemia. High phosphate concentrations are reduced in vitro and in vivo by a phosphate adsorption pill, which is synthesized by hydrolyzing ferrous sulfate in the presence of saccharides, to form an iron (III)-saccharide complex that is acid resistant and binds phosphate greater than iron (III) hydroxide alone. Under in vitro conditions, containing 3.26 mg P/dL, the iron (III)-sucrose complex showed the highest phosphate adsorption capacity at pH 2 with artificial gastric juice, 58.9 mg P/g binder. For the 7 day in vivo study, 0% (Group 1), 1% (Group 2), 4% (Group 3), and 8% (Group 4) iron (III)-sucrose complex was admixed into the rodent chow by weight and fed to 15 male Wistar rats. The weight and volume of the feces and urine, and the calcium, iron, and phosphorus excretions in the feces and urine samples were monitored for any signs of irregularity. Total urine outflow was collected during a 24-h period to determine the amount of phosphate recovered, which indicates the ability of the phosphate binder to reduce gastrointestinal phosphate absorption. The fecal iron excretion was significantly effected by the amount of binder ingested throughout the study for Group 2 (p < 0.001), Group 3 (p < 0.01), and Group 4 (p < 0.001). The urinary calcium excretion (mg/rat/24-h) significantly increased by the 7th day for Group 2 (p < 0.05) and Group 4 (p < 0.01) in comparison to the control. Finally, after 7 days, there was a significant drop in the urinary phosphorus levels (mg P/rat/24-h) in a dose dependent manner for Group 2: from 7.82 +/- 1.46 to 1.98 +/- 0.10 mg P/rat/24-h (102 mg P/dL/24-h; p < 0.05); Group 3: from 6.70 +/- 1.14 to 0.16 +/- 0.09 mg P/rat/24-h (6.0 mg P/dL/24-h; p < 0.01); and Group 4: from 8.25 +/- 0.67 to 0.04 +/- 0.01 mg P/rat/24-h (0.9 mg P/dL/24-h; p < 0.01). The results show that this new adsorbent might provide an alternative to conventional aluminum and calcium containing phosphate-binding agents for combating hyperphosphataemia.

Topics: Administration, Oral; Adsorption; Animals; Calcium; Feces; Ferric Compounds; Ferric Oxide, Saccharated; Glucaric Acid; Hydrogen-Ion Concentration; In Vitro Techniques; Male; Phosphates; Random Allocation; Rats; Rats, Wistar; Structure-Activity Relationship; Sucrose; Time Factors

As revealed by electron microscopy and electron diffraction, the physical state of ferric hydroxide micelles contained in iron-dextran, saccharated iron oxide, and hydrous ferric oxide ("ferric hydroxide") differs notably from the state of the ferric hydroxide in ferritin or hemosiderin. By virtue of this difference one can trace the intracellular transformation of colloidal iron, administered parenterally, into ferritin and hemosiderin. One hour after intraperitoneal injection of iron-dextran or saccharated iron oxide into mice, characteristic deposits were present in splenic macrophages, in sinusoidal endothelial cells of spleen and liver, and in vascular endothelial cells of various renal capillaries. Four hours after injection, small numbers of ferritin molecules were identifiable about intracellular aggregates of injected iron compounds; and by the 6th day, ferritin was abundant in close proximity to deposits of injected iron compounds. The latter were frequently situated in cytoplasmic vesicles delimited by single membranes. These vesicles were most frequently found in tissue obtained during the first 6 days after injection; and in certain of the vesicles ferritin molecules surrounded closely packed aggregates of injected material. Much unchanged ferric hydroxide was still present in macrophages and vascular endothelial cells 3 to 4 weeks after injection. While electron microscopy left no doubt about the identity of injected ferric hydroxide on the one hand, and of ferritin or hemosiderin on the other, histochemical tests for iron failed in this respect. Precipitation of ferric hydroxide (hydrous ferric oxide) from stabilized colloidal dispersions of iron-dextran was brought about in vitro by incubation with minced mouse tissue (e.g. liver), but not by incubation with mouse serum or blood. Subcutaneous injections of hydrous gel of ferric oxide into mice initially produced localized extracellular precipitates. Most of the material was still extracellular 16 days after injection, though part of it was phagocytized by macrophages near the site of injection; but apparently none reached the spleen in unaltered form. Five days after injection and thereafter, much ferritin was present in macrophages about the site of injection and in the spleen. The findings show that iron preparations widely used in therapy can be identified within cells, and that their intracellular disposition and fate can be followed at the molecular level. Considered in the light of p

Topics: Animals; Animals, Laboratory; Cytoplasm; Electrons; Ferric Compounds; Ferric Oxide, Saccharated; Ferritins; Glucaric Acid; Hemosiderin; Injections, Intraperitoneal; Iron; Liver; Macrophages; Mice; Microscopy; Microscopy, Electron; Pigments, Biological; Spleen