Iron Administration, Infection, and Anemia Management in CKD: Untangling the Effects of Intravenous Iron Therapy on Immunity and Infection Risk

Patients with chronic kidney disease (CKD) are at increased risk for infection, attributable to immune dysfunction, increased exposure to infectious agents, loss of cutaneous barriers, comorbid conditions, and treatment-related factors (eg, hemodialysis and immunosuppressant therapy). Because iron plays a vital role in pathogen reproduction and host immunity, it is biologically plausible that intravenous iron therapy and/or iron deficiency influence infection risk in CKD. Available data from preclinical experiments, observational studies, and randomized controlled trials are summarized to explore the interplay between intravenous iron and infection risk among patients with CKD, particularly those receiving maintenance hemodialysis. The current evidence base, including data from a recent randomized controlled trial, suggests that proactive judicious use of intravenous iron (in a manner that minimizes the accumulation of non-transferrin-bound iron) beneficially replaces iron stores while avoiding a clinically relevant effect on infection risk. In the absence of an urgent clinical need, intravenous iron therapy should be avoided in patients with active infection. Although serum ferritin concentration and transferrin saturation can help guide clinical decision making about intravenous iron therapy, definition of an optimal iron status and its precise determination in individual patients remain clinically challenging in CKD and warrant additional study.

Efficacy of a Low-Dose Intravenous Iron Sucrose Regimen in Peritoneal Dialysis Patients

Objective

Sufficient iron substitution leads to a decrease in the required recombinant human erythropoietin (rHuEPO) dose and/or an increased hematocrit in dialysis patients. Intravenous (IV) application of larger doses of iron sucrose may be associated with hyperferritinemia, appearance of catalytically free iron, and impaired phagocyte function. Therefore, we investigated the effectiveness of a low-dose IV iron regimen in peritoneal dialysis (PD) patients.

Patients and Interventions

Forty-five PD patients were followed over a period of 1 year. Serum ferritin, serum transferrin saturation, and hemoglobin were measured monthly. In cases of absolute iron deficiency (serum ferritin < 100 μg/L), 50 mg iron sucrose was given IV every second week. In cases of functional iron deficiency (ferritin ≥ 100 μg/L and transferrin saturation < 20%) and in iron repleted patients (ferritin ≥ 100 μg/L and transferrin saturation ≥ 20%), 50 mg IV iron sucrose was applied monthly. Iron therapy was stopped in cases of acute infection (until complete recovery) and when serum ferritin level was ≥ 600 μg/L.

Results

To analyze the influence of iron substitution on erythropoiesis and rHuEPO requirements, the EPO resistance index (ERI; quotient of rHuEPO dose in units/kilogram/week and hemoglobin in grams per deciliter) was calculated every 3 months. The ERI decreased significantly during the course of the study in the whole patient group ( p = 0.009) as well as in the subgroup of 21 patients with absolute iron deficiency ( p = 0.01). A nonsignificant decrease in the ERI was observed within the group of 14 iron repleted patients ( p = 0.5). There was no significant change in the ERI in 10 patients with functional iron deficiency ( p = 0.6).

Conclusion

The low-dose IV iron regimen used in this study substantially decreased rHuEPO requirements in patients with absolute iron deficiency and was effective in maintaining iron stores in iron repleted patients. However, in the absence of significant hyperparathyroidism, aluminum toxicity, or inadequate dialysis, it did not improve the ERI in patients with functional iron deficiency.

Efficacy and safety of a low monthly dose of intravenous iron sucrose in peritoneal dialysis patients

PURPOSE

Scientific data regarding intravenous iron supplementation in peritoneal dialysis (PD) patients are scarce. In attempting to administer the minimum monthly IV iron dose that could improve erythropoiesis, we wanted to assess the safety and efficacy of monthly maintenance intravenous administration of 100 mg iron sucrose in PD patients.

METHODS

In a 9-month prospective study, all clinically stable PD patients received intravenously 200 mg of iron sucrose as a loading dose, followed by monthly doses of 100 mg for five consecutive months. Levels of hemoglobin (Hb), ferritin, transferrin saturation (TSAT), reticulocyte hemoglobin content (CHr) and C-reactive protein (CRP) were measured before each administration and 3 months after the last iron infusion. Also, doses of concurrent erythropoietin administration were recorded.

RESULTS

Eighteen patients were eligible for the study. Mean levels of Hb and ferritin increased significantly (from 10.0 to 10.9 mg/dL, p = 0.01 and from 143 to 260 ng/mL, p = 0.005), as well as the increase in TSAT levels approached borderline significance (from 26.2 to 33.1%, p = 0.07). During the 6 months of iron administration, the erythropoietin dose was reduced in five patients and discontinued in one. During the 3 months following the last iron infusion, three of them again raised the erythropoietin dose to previous levels. None of the patients experienced any side effects related to IV iron administration.

CONCLUSIONS

A monthly maintenance intravenous dose of 100 mg iron sucrose may be a practical, effective, and safe in the short term, treatment of anemia in PD patients resulting in improved hemoglobin levels, iron indices, and erythropoietin response.

Effectiveness and safety of ferric carboxymaltose therapy in peritoneal dialysis patients: an observational study

Background

The efficacy of intravenous (IV) ferric carboxymaltose (FCM) has been demonstrated in haemodialysis and non-dialysis studies, but evidence is lacking in patients undergoing peritoneal dialysis (PD).

Methods

This multicentre, retrospective study evaluated the effectiveness and safety of FCM in patients on PD over 12 months. We retrospectively reviewed the electronic medical records of PD patients who initiated FCM treatment between 2014 and 2017 across seven Spanish centres.

Results

Ninety-one patients were included in the safety population (mean ± SD age 57.7 ± 15.0 years) and 70 in the efficacy population (mean age 50.9 ± 14.5 years). No hypersensitivity reaction, FCM discontinuation or dose adjustment due to a serious adverse event (SAE) was registered in the safety population. The most common non-SAEs reported were headache (four events), mild hypotension (three events) and hypertension (two events), among others. In the efficacy population (n = 70), 68.6% of patients achieved ferritin levels of 200–800 ng/mL, 78.4% achieved transferrin saturation (TSAT) >20%, and 62.8% achieved TSAT >20% and ferritin >200 ng/mL after 12 months of FCM initiation (P < 0.01). Haemoglobin (Hb) levels were maintained at >11 g/dL with a lower dose of darbepoetin throughout the follow-up. The sub-analysis of patients naïve to IV iron and with absolute or relative iron deficiency (n = 51) showed that 76.5% reached ferritin >200 ng/mL, 80.4% TSAT >20% and Hb increased (1.2 g/dL) after 4 months of FCM treatment (P < 0.01).

Conclusion

In this multicentre, retrospective, real-world study conducted in the PD population, FCM was effective, safe and easy to administer during routine clinical visits.

Randomized double-blind safety comparison of intravenous iron dextran versus iron sucrose in an adult non-hemodialysis outpatient population: A feasibility study

Background

Intravenous iron therapy is a treatment option for iron deficient patients who are intolerant to oral iron or where oral iron is ineffective, but with possible adverse effects. Currently, prospective studies comparing different intravenous iron formulations are needed to determine safety and efficacy of these agents.

Methods

We conducted a prospective, double-blind, randomized controlled trial (RCT) to assess the feasibility of a trial comparing the safety of high molecular weight intravenous iron dextran, Infufer®, with intravenous iron sucrose, Venofer®, in non-hemodialysis adult outpatients. Primary outcome was the occurrence of immediate severe drug reactions.

Results

We enrolled 143 patients in a one-year period. Overall, 45/143 (31.5 %) patients (20 iron dextran, 25 iron sucrose) developed 48 infusion reactions (14 immediate, 28 delayed, and 3 both). The risk of an immediate reaction was similar in both groups, 9/73 (12.3 %) iron dextran versus 8/70 (11.4 %) iron sucrose, RR = 0.93 (95 % CI; 0.38 to 2.27). The risk of a delayed reaction was significantly higher in the iron sucrose group 22/70 (31.4 %) versus the iron dextran group 9/73 (12.3 %), RR = 2.55 (95 % CI; 1.26 to 5.15; p = 0.0078).

Conclusion

In this limited feasibility study, no major differences in immediate reactions were seen, but a significantly higher number of delayed reactions were seen in the iron sucrose group. Further, under our assumptions and design a full RCT to evaluate the safety of different intravenous iron preparations is not feasible. Future studies should consider modifying the clinical outcomes, utilize multiple centers, and consider other emerging parenteral iron formulations. (ClinicalTrials.gov NCT005936197 January 3, 2008).

Safety and effectiveness of ferumoxytol in hemodialysis patients at 3 dialysis chains in the United States over a 12-month period

BACKGROUND

Intravenous (IV) iron is the treatment of choice for iron-deficiency anemia (IDA) in patients with dialysis-dependent chronic kidney disease (DD-CKD). However, IV iron products have been associated with serious adverse events (SAEs), including anaphylactoid reactions. Ferumoxytol is an IV iron preparation that can be injected over a short period of time. Although randomized clinical trials support ferumoxytol's efficacy and safety, additional insights may be drawn from the acquisition of long-term, repeat dosing efficacy and safety data in a real-world setting.

OBJECTIVE

The goal of this study was to characterize the effectiveness and safety profile of ferumoxytol as administered to adult DD-CKD patients with IDA in a real-world setting. The ability of ferumoxytol to maintain hemoglobin (Hb), transferrin saturation (TSAT), and ferritin treatment targets established by the 2006 Kidney Disease Outcomes Quality Initiative guidelines was determined in 3 medium-sized US-based dialysis chains.

METHODS

This retrospective, observational study was conducted to examine laboratory and dosing data for all patients who received any dose of ferumoxytol at 3 US-based dialysis chains over a 12-month period. Investigators and/or physicians from each of the chains also made independent determinations regarding the seriousness of any adverse event (AE). Special attention was paid to the incidence and types of AEs and SAEs that were potentially associated with ferumoxytol.

RESULTS

Over the 12-month observation period, 8666 patients (mean [SD] age in chains A, B and C, 63.9 [14.8], 63.9 [14.9] and 63.6 [15.1], respectively), were treated with 33,358 doses of ferumoxytol across the 3 chains. Treatment with ferumoxytol corresponded to an increased mean monthly Hb level relative to baseline (0.13-0.69 g/dL) and led to an increase in the proportion of patients maintained within the target Hb range of 10 to 12 g/dL (61%-72%). Ferumoxytol was also associated with increases in TSAT and ferritin that stabilized throughout the observation period. Incidence of AEs was similar across the 3 chains; between 0.07% and 1.77% of all patients treated at each chain experienced an AE associated with ferumoxytol administration. SAEs were reported in 0.2% of patients. The most common AEs reported (≥6 patients) were nausea (0.37% of patients), pruritus (0.29%), vomiting (0.25%), hypotension (0.21%), and dyspnea (0.20%). Two patients (0.02%) experienced anaphylactoid reactions. The AE profile of ferumoxytol remained consistent with that reported from controlled clinical trials.

CONCLUSIONS

These long-term data, which include repeat dosing in a large number of DD-CKD patients with IDA in a real-world setting, confirm the effectiveness of ferumoxytol in increasing and maintaining Hb levels within the target range and with favorable assessments of long-term safety.

Dialysis and pregnancy in end stage kidney disease associated with lupus nephritis

Female patients with systemic lupus erythematosus are often of childbearing age at diagnosis, and though fertility in these patients is similar to the general population, successful pregnancy remains a rare occurrence. This incidence is, however, increasing and the management of these high risk pregnancies is often further complicated by the patient's need for dialysis as a result of lupus nephritis (LN). We share our experience in managing two LN patients with successful pregnancies, one on automated peritoneal dialysis and the other on haemodialysis, as well as a review of cases in the literature.

Iron replacement therapy in cancer-related anemia

PURPOSE

The incidence, etiology, and management of cancer-related anemia is reviewed and the role of i.v. iron therapy in its treatment is described.

SUMMARY

Between 30% and 90% of patients with cancer develop anemia due to direct effects of the disease, its treatment, underlying nutritional deficiencies, and the inflammation that characterizes chronic disease. Although the use of erythropoiesis-stimulating agents (ESAs) increases hemoglobin levels and decreases the need for transfusions, up to 50% of patients do not to respond to these drugs, usually due to the presence of absolute or functional iron deficiency. Multiple clinical trials have demonstrated that i.v. iron supplementation in patients with cancer-related anemia improves the response rate to ESAs, reduces the time to target hemoglobin levels, decreases ESA requirements, reduces costs, and is more efficacious than oral iron. These benefits are seen without increased toxicity. Nonetheless, i.v. iron remains underused in patients with cancer, partly due to misinformation and misinterpretation of the clinical nature of adverse events.

CONCLUSION

Intravenous iron is underutilized in patients with cancer-related anemia. Based on published evidence, i.v. iron supplementation in patients with absolute or functional iron deficiency can improve patient responses to ESAs and reduce ESA requirements and may also reduce the need for transfusions and improve quality of life.

Is There a Difference between the Allergic Potencies of the Iron Sucrose and Low Molecular Weight Iron Dextran?

BACKGROUND

The objectives of the present trial were to compare the side effects and safety of two intravenous iron preparations (iron-dextran, iron-sucrose) in patients with end stage renal disease.

METHODS

A total of 60 patients were randomized and assigned to one of two treatment groups (iron-dextran, n = 30; iron-sucrose, n = 30). A standard test dose of 25 mg of low molecular weight iron-dextran and iron-sucrose were administered over 15 minutes during the initial visit, monitoring very closely for adverse reactions. If this dose was well tolerated, 75 mg of iron diluted in 100 mL of normal saline was administered over 30 minutes. Adverse reactions were recorded.

RESULTS

The mean age of the patients was 51.5+/-17.4 years (range, 21 to 80 years). Of the 30 patients who received low molecular weight iron-dextran, 11 developed side effects (pruritus, 1 patient; wheezing, 1 patient; chest pain, 1 patient; nausea, 4 patients; hypotension, 1 patient; swelling, 1 patient; headache, 2 patients). Of the 30 patients who received iron-sucrose, 13 developed side effects (pruritus, 1 patient; wheezing, 1 patient; diarrhea, 1 patient; nausea, 4 patients; hypotension, 2 patients; swelling, 1 patient; headache, 3 patients). Adverse events occurred with similar frequency in the two treatment groups in our study (p > 0.05). We did not observe any serious reactions in the two groups.

CONCLUSION

We conclude that the incidence of side effects associated with iron-dextran was not different than that of iron-sucrose in our study. Large scale randomized studies are needed to compare the full side effect profile of intravenous iron preparations more precisely.

Safety of ferumoxytol in patients with anemia and CKD

BACKGROUND

Iron deficiency anemia is a common complication in patients with chronic kidney disease (CKD). Currently available intravenous (IV) iron replacement therapies have either inconvenient regimens of administration or adverse event profiles that limit their utility in the outpatient setting. Ferumoxytol is a novel, semisynthetic, carbohydrate-coated, superparamagnetic iron oxide nanoparticle that is administered IV as an injection. The main objective of this study was to assess the safety of ferumoxytol for the treatment of patients with CKD stages 1 to 5 and 5D.

STUDY DESIGN

Phase 3, randomized, double-blind, placebo-controlled, crossover, multicenter study of a single 510-mg dose of ferumoxytol versus saline as placebo.

SETTING & PARTICIPANTS

750 patients with CKD stages 1 to 5 and 5D.

INTERVENTION

An IV injection of either 17 mL of ferumoxytol or saline placebo over 17 seconds on day 0 and the alternate agent on day 7.

OUTCOMES & MEASUREMENTS

Descriptive comparison of adverse events, laboratory tests, and vital signs.

RESULTS

Of 750 randomly assigned patients with CKD, 60% were not on dialysis therapy. 713 patients received ferumoxytol, and 711 received placebo. There were 420 adverse events reported; 242 in 152 patients (21.3%) with ferumoxytol and 178 in 119 patients (16.7%) with placebo. The incidence of related adverse events was 5.2% with ferumoxytol and 4.5% with placebo. The most common related adverse events after each treatment included symptoms related to the injection/infusion site, dizziness, pruritus, headache, fatigue, and nausea. Serious adverse events occurred in 21 patients (2.9%) after ferumoxytol and 13 patients (1.8%) after placebo. Serious related adverse events were observed in 1 patient (0.1%) after each treatment. There was no meaningful decrease in blood pressure after administration of ferumoxytol or placebo.

LIMITATIONS

Follow-up was 7 days after each study treatment.

CONCLUSIONS

Ferumoxytol is well tolerated and has a safety profile similar to placebo in anemic patients with CKD stages 1 to 5 and 5D.

Peritoneal effects of intravenous iron sucrose administration in rats

Intravenous iron supplementation is commonly used in uremic patients treated with peritoneal dialysis. Infusion of iron compounds results in various systemic noxious effects, mainly because of its prooxidant and proinflammatory actions. The authors studied how the intravenous infusion of iron sucrose (IS) affects intraperitoneal homeostasis in rats undergoing acute peritoneal dialysis. Experiments were performed on Wistar rats, which were infused intravenously with IS in a dose 10 mg/kg body weight or with normal saline in the controls. Simultaneously, 4-hour acute peritoneal dialysis was started. At the end of the dialysis, systemic and peritoneal inflammatory reaction and peritoneal permeability were evaluated. Compared with controls, rats exposed to IS showed increased dialysate iron concentration by +70%, P<0.001, and in the differential cell count, more eosinophils (+113%, P<0.05) and fewer macrophages (-16%, P<0.05) existed. In in vitro conditions, macrophages obtained from IS-treated rats released more tumor necrosis factor-alpha (TNF-alpha; +173%, P<0.05) upon stimulation with endotoxin. Additionally increased (+73%, P<0.01) dialysate elastase activity was found in IS-treated animals. Rats infused with IS demonstrated increased peritoneal permeability to total protein (+60%, P<0.001) as compared with control animals. When rats with simultaneous peritonitis received intravenous IS, ex vivo isolated peritoneal leukocytes generated more free radicals (+73%, P<0.05) than did cells harvested from control animals. It has been concluded that intravenous infusion of IS affects the intraperitoneal homeostasis in rats, moving it toward the inflammatory state. These changes may contribute to peritoneal damage.

Intravenous versus Oral Iron Supplementation in Peritoneal Dialysis Patients

Iron supplementation is required in a preponderance of peritoneal dialysis (PD) patients treated with erythropoietic stimulatory agents (ESAs). Although many authors and clinical practice guidelines recommend primary oral iron supplementation in ESA-treated PD patients, numerous studies have clearly demonstrated that, because of a combination of poor bioavailability of oral iron, gastrointestinal intolerance, and noncompliance, oral iron supplementation is insufficient for maintaining a positive iron balance in these patients over time. Controlled trials have demonstrated that, in iron-deficient and iron-replete PD patients alike, intravenous (IV) iron supplementation results in superior iron stores and hemoglobin levels with fewer side effects than oral iron produces. Careful monitoring of iron stores in patients receiving IV iron supplementation is important in view of conflicting epidemiologic links between IV iron loading and infection and cardiovascular disease. Emerging new iron therapies such as heme iron polypeptide and ferumoxytol may further enhance the tolerability, efficacy, and ease of administration of iron in PD patients.

A randomized controlled trial of oral versus intravenous iron in chronic kidney disease

BACKGROUND

It is unknown whether intravenous iron or oral iron repletion alone can correct anemia associated with chronic kidney disease (CKD). We conducted a randomized multicenter controlled trial in adult anemic, iron-deficient non-dialysis CKD (ND-CKD) patients (>or=stage 3) not receiving erythropoiesis-stimulating agents (ESAs).

METHODS

The participants were randomized to receive either a sodium ferric gluconate complex (intravenous iron) 250 mg i.v. weekly x 4 or ferrous sulfate (oral iron) 325 mg t.i.d. x 42 days. Hemoglobin (Hgb), ferritin and transferrin saturation (TSAT) were measured serially, and the Kidney Disease Quality of Life (KDQoL) questionnaire was administered on days 1 and 43. The primary outcome variable was change from baseline (CFB) to endpoint in Hgb values.

RESULTS

Seventy-five patients were analyzed (intravenous iron n = 36, oral iron n = 39). CFB in Hgb was similar in the two groups (intravenous iron 0.4 g/dl vs. oral iron 0.2 g/dl, p = n.s.). However, the increase in Hgb was only significant with intravenous iron (p < 0.01). In comparison to oral iron, intravenous iron achieved greater improvements in ferritin (232.0 +/- 160.8 vs. 55.9 +/- 236.2 ng/ml, p < 0.001) and TSAT (8.3 +/- 7.5 vs. 2.9 +/- 8.8%, p = 0.007). Intravenous iron caused greater improvements in KDQoL scores than oral iron (p < 0.05). The most common side effect reported with intravenous iron was hypotension, while constipation was more common with oral iron.

CONCLUSIONS

Oral and intravenous iron similarly increase Hgb in anemic iron-depleted ND-CKD patients not receiving ESAs. Although in comparison to oral iron, intravenous iron may result in a more rapid repletion of iron stores and greater improvement in quality of life, it exposes the patients to a greater risk of adverse effects and increases inconvenience and cost.

The safety and efficacy of ferumoxytol therapy in anemic chronic kidney disease patients

BACKGROUND

Administration of safe and effective iron therapy in patients with chronic kidney disease is a time consuming process. This phase II clinical trial studied ferumoxytol, a semi-synthetic carbohydrate-coated iron oxide administered by rapid intravenous injection to anemic chronic kidney disease patients (predialysis or undergoing peritoneal dialysis).

METHODS

Inclusion criteria included hemoglobin < or =12.5 g/dL and transferrin saturation < or =35%. Twenty-one adult patients were randomized to receive ferumoxytol in a regimen of 4 doses of 255 mg iron in 2 weeks or 2 doses of 510 mg iron in 1 to 2 weeks. Ferumoxytol was administered at a rate of up to 30 mg iron/sec.

RESULTS

The maximum hemoglobin response following ferumoxytol administration occurred at 6 weeks, increasing from a baseline of 10.4 +/- 1.3 g/dL to 11.4 +/- 1.2 g/dL (P < 0.05). Ferritin increased from a baseline of 232 +/- 216 ng/mL to a maximum of 931 +/- 361 ng/mL at 2 weeks (P < 0.05), while the baseline transferrin saturation increased from 21 +/- 10% to 37 +/- 22% at 1 week (P < 0.05). Seven adverse events in 5 patients during this trial were deemed possibly related to ferumoxytol, none serious. These events included constipation, chills, tingling, a gastrointestinal viral syndrome, delayed pruritic erythematous rash, and transient pain at the injection site.

CONCLUSION

Although larger studies are required, this small study demonstrates that ferumoxytol can be safe and effective in increasing iron stores, is associated with an increased hemoglobin response, and is well tolerated at a rapid infusion rate.

The safety and efficacy of an accelerated iron sucrose dosing regimen in patients with chronic kidney disease

BACKGROUND

Provision of adequate iron to support erythropoiesis in patients with chronic kidney disease (CKD) is time consuming and may present adherence problems for patients in the outpatient setting. We studied an accelerated regimen of high-dose intravenous iron sucrose therapy in a cohort of iron-deficient, anemic CKD patients.

METHODS

Intravenous iron sucrose 500 mg was infused over three hours on two consecutive days in 107 CKD patients (glomerular filtration rate, 32.3 +/- 19.6 mL/min/1.73m2, baseline hemoglobin 10.2 +/- 1.7 g/dL). Iron indices (transferrin saturation, ferritin) were measured at baseline and at two and seven days after completion of the iron regimen. Blood pressures were monitored immediately prior to, and hourly throughout the iron sucrose infusions.

RESULTS

Transferrin saturation and serum ferritin increased from 18.5 +/- 8.5% and 177 +/- 123.8 ng/mL at baseline to 40.2 +/- 22.3% and 811 +/- 294.1 ng/mL in 102 evaluated patients (P < 0.015). In 55 patients with additional measurements at 7 days post-dosing, the transferrin saturation and ferritin had fallen to 26.3 +/- 10.6% and 691 +/- 261.8 ng/mL (P < 0.015 compared to two days' post-dose). Blood pressure rose slightly, but not significantly, throughout the infusions, and altering the infusion rate was not necessary. Two patients had seven adverse events that were considered related to iron sucrose.

CONCLUSION

An accelerated regimen of high-dose intravenous iron sucrose therapy in CKD patients is safe and effective in restoring iron stores, and may potentially save time and improve patient adherence.

Controversies in iron management

BACKGROUND

Iron therapy is required in hemodialysis patients receiving erythropoietic stimulators in order to achieve the target hemoglobin in the most efficient way. While oral iron has been disappointing in this regard, parenteral iron has been widely used, despite a significant incidence of severe side effects when iron dextran is used. The recent availability of a more effective form of oral iron (heme-iron), and safer forms of parenteral iron (iron sucrose and iron gluconate) has made iron management in this population simpler. Many questions remain, however, about the use, efficacy, and safety of these compounds in hemodialysis patients.

METHODS

Current literature was reviewed and combined with the authors' clinical experience to address a number of current questions regarding the use of iron in hemodialysis patients.

RESULTS

Although oral non-heme iron is infrequently sufficient to maintain iron stores in hemodialysis patients, recent studies suggest that heme-iron may be more useful in this regard. Heme-iron is absorbed to a greater extent than non-heme iron, and is better tolerated. Small studies have shown that when heme-iron is administered, less parenteral iron and lower doses of erythropoietin (EPO) are needed to maintain target hemoglobin. Current evidence suggests that both iron sucrose and iron gluconate are safer than iron dextran, and the latter should only be used in extraordinary circumstances. While in vitro studies have demonstrated some differences in the effects of iron sucrose and iron gluconate on cellular toxicity, the clinical importance of these has not been determined. Both compounds can be used safely for repletion and maintenance therapy, and doses of up to 300 mg of either are generally well tolerated when such higher doses are needed, as in peritoneal dialysis (PD) patients or chronic kidney disease (CKD) patients not on dialysis.

CONCLUSION

A number of questions remain regarding the appropriate use, efficacy, and potential toxicity of iron therapy in dialysis patients. Further prospective research should address the myriad questions raised in this review.

Chronic use of sodium ferric gluconate complex in hemodialysis patients: safety of higher-dose (> or =250 mg) administration

BACKGROUND

Almost all hemodialysis (HD) patients require intravenous iron therapy to correct their anemia and maintain their iron stores. Sodium ferric gluconate complex (SFGC) is approved by the Food and Drug Administration (FDA) for treatment of iron deficiency anemia in HD patients at individual doses up to 125 mg over 10 minutes (12.5 mg/min) and has been shown to have a superior safety profile compared with iron-dextran. Higher individual doses of SFGC would permit more rapid repletion of iron stores and greater flexibility in maintenance iron therapy as well as simplify treatment of peritoneal dialysis patients and chronic kidney disease patients.

METHODS

The authors reviewed the safety and tolerability of higher-dose SFGC infusions (> or =250 mg) in 144 HD patients who were previously tolerant to a single 125-mg dose of SFGC. These 144 patients received a total of 590 doses of > or =250 mg of SFGC; 571 doses were 250 mg SFGC, and most of these were infused over 1 hour, an infusion rate of 4.17 mg/min. The other 19 doses were 312.5 mg (n = 1), 375 mg (n = 14), and 500 mg (n = 4). Infusion rates varied from 1.22 mg/min to 25.0 mg/min.

RESULTS

Only one patient was considered intolerant to higher-dosing SFGC after having pruritus after a second 250-mg dose of SFGC. Three patients had nonserious events that did not preclude further dosing of SFGC.

CONCLUSION

Administration of 250 mg SFGC over 1 hour is safe and well tolerated. Individual doses of 375 mg and 500 mg SFGC also were well tolerated, but further research and experience are needed to confirm the safety and tolerance of these doses.