Serum soluble transferrin receptor reflects erythropoiesis but not iron availability in erythropoietin-treated chronic hemodialysis patients

BACKGROUND: The diagnosis of iron deficiency using the current commonly used tests is usually difficult in hemodialysis patients. Soluble transferrin receptor (sTfR) has caught the attention of physicians recently as regards its use as a parameter for the evaluation of iron status. This study was conducted in order to evaluate the correlation of serum soluble transferrin receptor (sTfR) concentration with hematological parameters and iron profiles, in the role of identifying iron deficiency among dialysis patients. METHODS: Seventy-three patients having received chronic hemodialysis and stable maintenance recombinant human erythropoietin (rHuEPO) therapy were included. Iron, total iron-binding capacity, ferritin and sTfR were measured in the first week. Following this, these patients began to receive intravenous iron dextran (2 mg/kg/week) for 4 weeks. The hematocrit (Hct), hemoglobin (Hb) levels and reticulocyte counts were evaluated weekly. At the beginning of fifth week, the sTfR level was measured again. Patients were classified as belonging to one of the following groups: serum ferritin < 100 microg/L - absolute iron-deficient group; initial ferritin level > or = 100 microg/L with an increase in hemoglobin of greater than 1 g/dL at the end of the study occult iron deficiency group; others - non iron-deficient group. RESULTS: Seventy-one patients completed the study. The concentration of sTfR was positively correlated with Hct, Hb and reticulocyte index at the beginning (r = 0.236, p = 0.047; r = 0.257, p = 0.04; r = 0.401, p < 0.01, respectively) and at the end of the study (r = 0.384, p < 0.01; r = 0.338, p < 0.01; r = 0.427, p < 0.001, respectively). After 4 weeks of iron and rHuEPO therapy, the sTfR concentration increased, rather than declined, from 21.85 +/- 8.06 nM to 23.76 +/- 7.42 nM (p = 0.04) and the change was positively correlated with the changes in Hct, Hb and reticulocyte index. The administered rHuEPO doses did not differbetween the iron deficiency group (absolute deficiency, n = 3; occult deficiency, n = 10) and non-iron deficiency group (n = 58). The sTfR levels failed to identify the occult iron deficiency group because there was no difference between occult iron-deficient and non-iron-deficient patients (24.73 +/- 9.09 nM versus 21.60 +/- 7.89 nM, p = 0.34). Instead, transferrin saturation (TS) could be a differential marker between the 2 groups (19.0 +/- 10.9% versus 30.1 +/- 12.7%, p = 0.012). CONCLUSION: The serum sTfR concentration is indeed an appropriate marker for erythropoiesis. The erythropoitic effect of administered rHuEPO could mask the effect of iron status on the sTfR concentration. This might make the sTfR concentration no longer an appropriate index to identify the presence of occult iron deficiency. Thus, TS and ferritin currently remain better methods for the evaluation of iron status in rHuEPO-treated chronic hemodialysis patients.     

Continuous intravenous sodium ferric gluconate improves efficacy in the maintenance phase of EPOrHu administration in hemodialysis patients

Although intravenous iron has proved to optimize the efficacy of EPOrHu in hemodialysis patients, hitherto no consensus exists with respect to the best regimen of intravenous iron administration. We started a prospective randomized study in 26 patients undergoing chronic hemodialysis who had adequate iron metabolism indices (serum ferritin >100 microg/l; %TSAT >20%; %HypoE <10% and CHr >26 pg) and were in the maintenance phase of EPOrHu administration (target hemoglobin obtained >10 g/dl). All patients were receiving sodium ferric gluconate (Ferrlecit) intermittently prior to the study and after a 1-month wash-out period where iron was not administered patients were randomized to receive the same previous dose of intravenous iron either in a continuous (6.25-21.3 mg in every hemodialysis session) or an intermittent regimen (62.5 mg every 1-4 weeks, not modifying the previous schedule of administration). At 16 weeks, the continuous group showed a significant increment in serum Hb (11.83 +/- 1.12 g/dl) with respect to baseline (10.96 +/- 1.31 g/dl) (p < 0.05), whereas no differences were obtained in intermittent group (baseline: 11.16 +/- 1.03 g/dl; 16 weeks: 11.14 +/- 0.90 g/dl, NS). In contrast with the intermittent group, serum ferritin increased significantly in the continuous group (16 weeks: 508 +/- 157 microg/l; baseline: 368 +/- 56 microg/l; p < 0.05), whereas %TSAT and CHr did not modified during the study in both groups. %HypoE increased significantly with respect to baseline values in the continuous group (p < 0.05) and close to significantly different in the intermittent group (p = 0.06). Our study suggests that hemodialysis patients in the maintenance phase of EPOrHu administration would obtain further benefit in terms of serum hemoglobin level with a continuous intravenous serum ferric gluconate regimen, at least in the short term.     

Comparison of intravenous ascorbic acid versus intravenous iron for functional iron deficiency in hemodialysis patients

The effect of intravenous ascorbic acid was compared with that of intravenous iron in the treatment of functional iron deficiency, as defined as serum ferritin levels over 300 ng/ml and serum iron levels below 50 microg/dl, in patients on chronic hemodialysis. Thirteen patients on chronic hemodialysis with functional iron deficiency received intravenous injections of ascorbic acid, 100 mg, three times a week, after hemodialysis. The therapy was continued until serum ferritin decreased to below 300 ng/ml (3 months at the maximum). The iron and control group were composed of patients who had serum iron levels below 50 microg/dl within 3 months after serum ferritin rose to over 300 ng/ml. Seven patients with the iron group received more than a total of 10 intravenous injections of saccharated ferric oxide (40 mg/dose) after hemodialysis, and seven patients with the control group received no iron preparation during the 3 months. In the ascorbic acid group, while hemoglobin did not change from 10.9 +/- 0.5 g/dl (mean +/- SE) during the three-month period, serum iron increased significantly from 37 +/- 4 microg/dl to 49 +/- 4 microg/dl after one month (p<0.01), and remained elevated until the end of the three-month period. Serum ferritin decreased significantly from 607 +/- 118 ng/ml to 354 +/- 30 ng/ml after 3 months (p<0.01). In the iron group, hemoglobin and serum iron increased significantly from the respective pre-treatment levels during the 2-month period, and serum ferritin rose significantly after 3 months. In the control group, hemoglobin, serum iron and ferritin levels decreased significantly from the respective pre-treatment levels during the 3 months. The recombinant erythropoietin dose remained stable for three months in the ascorbic acid, iron, and control groups, respectively. These results suggest that in hemodialysis patients with a functional iron deficiency, treatment with intravenous ascorbic acid can prevent iron overload due to treatment with intravenous iron, and provide a useful adjuvant means of maintaining hemoglobin and serum iron levels.     

Intravenous ascorbic acid as an adjuvant therapy for recombinant erythropoietin in hemodialysis patients with hyperferritinemia.

BACKGROUND: Inadequate iron mobilization and defective iron utilization may cause recombinant erythropoietin (rEPO) hyporesponsiveness in hemodialysis (HD) patients with iron overload. We have demonstrated that intravenous ascorbic acid (IVAA), but not intravenous iron medication, can effectively circumvent the functional iron-deficient erythropoiesis associated with iron overload in HD patients. However, it is uncertain whether all HD patients with hyperferritinemia will consistently respond to IVAA and which index may indicate functional iron deficiency in the special entity. Therefore, a prospective study was conducted to establish the guidelines for IVAA adjuvant therapy. METHODS: Sixty-five HD patients with serum ferritin levels of more than 500 microgram/liter were recruited and divided into the control (N = 19) and IVAA (N = 46) groups. IVAA patients with a hematocrit (Hct) of less than 30% received 300 mg of ascorbic acid three times per week for eight weeks. Controls had a Hct of more than 30% and did not receive the adjuvant therapy. Red blood cell and reticulocyte counts, iron metabolism indices, erythrocyte zinc protoporphyrin (E-ZPP), and the concentrations of plasma ascorbate and oxalate were examined before and following the therapy. RESULTS: Thirteen patients (four controls and nine IVAA patients) withdrew by the end of the study. Eighteen patients had a dramatic response to IVAA with a significant increase in their hemoglobin and reticulocyte index and a concomitant 24% reduction in rEPO dose after eight weeks. This paralleled a significant rise in serum iron and transferrin saturation (TS) and a fall in E-ZPP and serum ferritin (baselines vs. 8 weeks, serum iron 68 +/- 37 vs. 124 +/- 64 microgram/dl, TS 27 +/- 10 vs. 48 +/- 19%, E-ZPP 123 +/- 44 vs. 70 +/- 13 micromol/mol heme, and serum ferritin 816 +/- 435 vs. 587 +/- 323 microgram/liter, P < 0. 05). Compared with responders, mean values of hemoglobin, rEPO dose, iron metabolism parameters, and E-ZPP showed no significant changes in controls (N = 15) and in non-responders (N = 19). Thirty-seven patients (18 responders and 19 non-responders) were further analyzed by receiver operating characteristic curves to seek the criteria for prediction of a response to IVAA treatment. The results showed that E-ZPP at a cut-off level of more than 105 micromol/mol heme and TS at a level of less than 25% were more specific to confirm the status of functional iron deficiency in iron-overloaded patients. The two criterion values had the highest accuracy to predict a response to treatment. CONCLUSIONS: Functional iron-deficient erythropoiesis plays a role in rEPO-hyporesponsive anemia in HD patients with hyperferritinemia. IVAA may be an adjuvant therapy for rEPO in these patients, and E-ZPP of more than 105 micromol/mol heme and TS of less than 25% should be used to guide the IVAA treatment.     

Predictors of the response to treatment in anemic hemodialysis patients with high serum ferritin and low transferrin saturation

Treating hemodialysis patients to combat anemia corrects hemoglobin but exacerbates iron deficiency by utilizing iron stores. Patients needing iron should receive this by intravenous (i.v.) means. The Dialysis patients' Response to IV iron with Elevated ferritin (DRIVE) trial investigated the role of i.v. iron in anemic patients with high ferritin, low transferrin saturation, and adequate epoetin doses. We examined whether baseline iron and inflammation markers predict the response of hemoglobin to treatment. Patients (134) were randomized to no added iron or to i.v. ferric gluconate for eight consecutive hemodialysis sessions spanning 6 weeks with epoetin increased by 25% in both groups. The patients started with hemoglobin less than or equal to 11 g/dl, ferritin between 500 and 1200 ng/ml, and transferrin saturation of less than 25%. Significantly, patients with a reticulocyte hemoglobin content greater than or equal to 31.2 pg were over five times more likely to achieve a clinically significant increase in hemoglobin of greater than 2 g/dl. Lower reticulocyte hemoglobin contents did not preclude a response to i.v. iron. Significantly higher transferrin saturation or lower C-reactive protein but not ferritin or soluble transferrin receptor levels predicted a greater response; however their influence was not clinically significant in either group. We conclude that none of the studied markers is a good predictor of response to anemia treatment in this patient sub-population.     

Increase of body iron stores estimated by the increase of serum ferritin concentration during a treatment of 200 mg Fe++ daily after gastrointestinal surgery

A 6-week iron therapy of 200 mg Fe++ daily was given to 13 men and 12 women who had previously undergone various kinds of common gastrointestinal surgery and who had empty iron stores estimated from low serum ferritin concentration. The results were compared with those of a control group corresponding to the study group in respect of sex, number of patients, primary disease, previous operation, empty iron stores (serum ferritin), blood hemoglobin, serum iron, sedimentation rate, blood leukocytes, serum transferrin, folate and vitamin B12. The iron therapy restored the lack of body iron, for the serum ferritin concentrations increased from 12 +/- 7 to 30 +/- 11 micrograms/l (p less than 0.001) in the men and from 10 +/- 6 to 30 +/- 12 micrograms/l (p less than 0.001) in the women, whereas the corresponding changes in the control group were from 10 +/- 9 to 11 +/- 8 micrograms/l and from 11 +/- 8 to 13 +/- 11 micrograms/l in the men and women, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Noninvasive assessment of skin iron content in hemodialysis patients. An index of parenchymal tissue iron content?

Iron overload has been described in patients undergoing chronic hemodialysis. The present study was undertaken to evaluate a rapid, noninvasive method for determination of skin iron by the technique of diagnostic x-ray spectrometry (DXS). Thirty-five patients receiving chronic hemodialysis treatment entered the study and were compared with 25 normal controls. Since pathological skin iron deposition occurs mainly at the dermal-epidermal junction in the basal cells of the epidermis, measurements were made in the thenar eminence representing mainly epidermal tissue (FeE), and in the forearm representative mainly of dermis (FeD). The mean +/- SD FeE iron concentrations were equivalent to 14.5 +/- 8.8 and 18.2 +/- 10.2 parts per million wet weight tissue (ppm) and both were significantly higher than in normal controls in which they averaged 9.2 +/- 2.5 ppm (P less than 0.005) and 10.2 +/- 3.2 ppm (P less than 0.001), respectively. There was significant positive correlation between individual skin iron determinations with the total number of blood transfusions received, the rate of blood transfusion, and with serum ferritin levels. Bone marrow hemosiderin was examined in six patients and showed a similar trend. Despite correlation only with indirect indices of tissue iron, our findings suggest that DXS may serve as a reliable quick method for noninvasive estimation of nonreticuloendothelial tissue iron deposition in hemodialysis patients suspected of having transfusional iron overload. The method may be valuable in monitoring the effects of chelation therapy.     

Impairment of phagocyte oxidative metabolism in hemodialyzed patients with iron overload

In order to study the influence of iron overload on the polymorphonuclear leucocyte (PMN) metabolism of patients on chronic hemodialysis, generation of superoxide anion (O2-) by PMN in whole blood was compared in two groups of hemodialyzed patients: group A consisted of twenty-one individuals with serum ferritin levels above 1000 ng/ml and group B of nineteen individuals with serum ferritin levels below 1000 ng/ml. Whereas basal production of O2- was similar in the two groups (6.3 +/- 4.6 vs 11.5 +/- 8.3 nmoles O2- 10(6) granulocytes-1 15 min-1) (mean +/- s.e.m.), PMN response to opsonized zymosan was significantly lower in group A as compared with group B (86.5 +/- 6.3 vs 120.4 +/- 8.2 nmoles O2- 10(6) granulocytes-1 15 min-1) (p less than 0.01). Superoxide anion generation induced by the dialysis procedure was reduced in eight patients from group A (89.2 +/- 32.1) as compared with eight patients from group B (374.3 +/- 100.0 nmoles O2- 10(6) granulocytes-1 15 min-1) (p less than 0.05). These data suggest that iron overload may be involved in the impairment of neutrophil phagocytosis in patients on chronic hemodialysis.     

Determinants of soluble CD23 antigen levels in hemodialysis patients: effect of 1.25 dihydroxyvitamin D3 and recombinant human erythropoietin treatment.

BACKGROUND: The immunodeficiency of end-stage renal disease (ESRD) paradoxically coexists with T cell and monocyte activation. In spite of well known defective antibody responses in ESRD, the functional status of B cells in the immune system dysregulation of uremia is still controversial. Soluble CD23 (sCD23) antigen is a recently identified B cell activation marker and is also involved in T cell activation process. Effects of parathyroid hormone (PTH), red blood cells and ferritin on T and B cell functions have been shown both in vivo and in vitro. PATIENTS AND METHODS: In this study, serum levels of sCD23 in hemodialysis patients were determined to evaluate the functional status of B cells and possible linkages between this cytokine and PTH levels, ferritin levels, red blood cell counts were investigated. RESULTS: Serum sCD23 levels were significantly elevated in hemodialysis patients relative to healthy controls (12.5+/-8.4 micro/l vs. 2.4+/-1.1 micro/l, p<0.001). Serum sCD23 levels were negatively correlated with red blood cell count (r = -0.61, p = 0.009) and serum PTH levels (r = -0.62, p = 0.008), while positively correlated with serum ferritin levels (r = 0.63, p = 0.007) in hemodialysis patients. We also investigated the immunumodulator effects of 1.25 dihydroxyvitamin D3 (1.25OHD3) and recombinant human erythropoietin (rHu-Epo) treatment in hemodialysis patients. 1.25OHD3 treatment for eight weeks did not change serum sCD23 levels in hemodialysis patients (n = 8). On the other side, rHu-Epo administration for 16 weeks led to a decrease in serum sCD23 levels (17.7+/-8.6 microg/l vs. 9.8+/-3.5 microg/l, p = 0.007) in these patients (n = 9). CONCLUSION: These results suggests that similar to T cells, B cells are activated in uremia and the degree of this activation is correlated with red blood cell count, serum parathyroid hormone levels and iron status of the hemodialysis patients. Moreover, B cell activation could be altered by recombinant human erythropoietin therapy in hemodialysis patients.     

Effect of body iron stores on serum aluminum level in hemodialysis patients.

To evaluate the influence of body iron stores on the serum aluminum (Al) level, we studied the correlation between iron status (the serum ferritin, serum iron and transferrin saturation) and serum Al levels in 68 severely anemic hemodialysis patients. Among them, 36 underwent the desferrioxamine (DFO) mobilization test. These 68 patients were divided into three groups according to their serum ferritin level. The basal Al level in the patient group was 41.4 +/- 37.4 micrograms/l (control, 4.1 +/- 2.4 micrograms/l). The serum Al level after DFO infusion of the patient group was 111.1 +/- 86.8 micrograms/l. A significantly higher basal Al and peak Al level after DFO infusion were found in group 1 patients (serum ferritin less than 300 micrograms/l) when compared to group 2 (serum ferritin 300-1,000 micrograms/l) and group 3 (serum ferritin greater than 1,000 micrograms/l) patients. A significant negative correlation between serum ferritin and basal serum Al (r = -0.544, p = 0.0001), as well as peak serum Al after DFO infusion (r = -0.556, p = 0.0001), was noted. Similarly, a negative relationship between serum Al (both basal and peak) and either serum iron or transferrin saturation was noted. However, there was no correlation between the serum Al level and the dosage of aluminum hydroxide. In conclusion, serum ferritin, serum iron and transferrin saturation were inversely correlated with serum Al in our hemodialysis patients. Iron deficiency may probably increase Al accumulation in these patients.     

Total dose infusion iron dextran therapy in predialysis chronic renal failure patients

BACKGROUND: Intravenous iron therapy is now the standard modality of iron supplementation in hemodialysis patients, but its role in predialysis chronic renal failure patients is less well established. The efficacy and safety of intravenous iron dextran as a total dose infusion in predialysis chronic renal failure patients, not receiving erythropoietin was assessed in this study. METHODS: Fifty-six predialysis chronic renal failure patients with anemia, not receiving erythropoietin were included in the study, after obtaining informed consent. Hemoglobin, serum creatinine, creatinine clearance rate and serum ferritin were assessed in all the patients at baseline. Iron dextran in a dose of 1 g dissolved in 500 mL normal saline was administered to all patients as a total dose infusion over 6 h after a prior test dose. Patients were kept in hospital under observation for at least 24 h. All the parameters were repeated in all the patients at 12 weeks and in 21 patients at 1 year. RESULTS: The mean hemoglobin (g/dL) in the patients at baseline and at 12 weeks was 8.28 +/- 0.57 and 9.22 +/- 0.44 respectively (p < 0.001). The mean serum ferritin (ng/mL) increased from 29.73 +/- 9.38 at baseline to 218.43 +/- 15.66 at 12 weeks (p < 0.00001). The mean ferritin value in the 21 patients at 1 year was 136.5 +/- 23.4 (p < 0.01). There were no major adverse events and only minor side effects were observed in 4.9% patients. CONCLUSION: Iron dextran as a total dose infusion corrects anemia in predialysis patients and is an effective method to replenish iron stores. The effect on serum ferritin are evident even at 1 year after the total dose infusion.     

Iron overload and mobilization in long-term hemodialysis patients

Iron overload from repeated transfusions of RBCs in long-term hemodialysis patients is a problem of increasing clinical significance. We report on the prevalence of and diagnostic criteria for identification of hemodialysis patients with iron overload. In 150 unselected hemodialysis patients, 62 (41%) had ferritin levels greater than 2,000 ng/mL (normal = 10 to 360 ng/mL). In 16 of these patients, accurate transfusion histories were obtained and ferritin levels correlated with calculated transfusional iron burden (r = 0.553, P less than .05). These patients could be divided into two distinct groups on the basis of their response to a single dose (2 g, IV) of deferoxamine: "high" responders had twice the level of feroxamine (the chelated product of deferoxamine and iron) of the "low" responders (P less than .001). High responders also had significantly higher prevalence of the "hemochromatosis" alleles A3, B7, and B14 than a large group of dialysis patients awaiting transplantation (71% v 37%, P less than .001). In two patients with iron overload and clinically significant bone disease, bone histology revealed prominent iron staining at the calcification front. We conclude that transfusional iron overload is a significant clinical problem in long-term hemodialysis patients, that may also be associated with bone pathology.     

Erythropoietin requirements increase following hospitalization in end-stage renal disease patients.

The effect of hospitalization on an ESRD patient's hemoglobin (Hgb) level and erythropoietin (Epo) requirement has not been investigated. We postulated patients with end stage renal disease required an increased Epo dose to maintain stable Hgb during hospitalization and for a period following discharge. To evaluate this hypothesis, we conducted a retrospective chart review on 65 hemodialysis patients. All hemodialysis patients admitted for more than 2 days who did not have more than the index hospitalizations for 2 months prior to and following discharge were included. Multiple parameters including Hgb, Epo dose, intravenous iron dose, serum iron, TIBC, and ferritin during the 2 months before and the two months after hospitalization, Hgb at admission and discharge, Hgb trough, surgery, blood transfusions and co-morbid factors were evaluated. Statistical significance was evaluated using ANOVA or rank-sum testing, as appropriate. In 65 hemodialysis patients (24 M/41 F, age 58 +/- 2.2 years, mean +/- SEM), Hgb levels following discharge and for 2 subsequent months were significantly lower than 2 months prior to admission (11.4 +/- 0.25 vs. 10.7 +/- 0.22 g/dl, p < 0.01). This occurred in spite of an increase in Epo dose (128 +/- 14 vs. 185 +/- 21 U/kg/week, p < 0.0001) over this 2-month period. There was no difference in the iron saturation before and after hospitalization (22 vs. 23%,p > 0.05). There were also no apparent effects of comorbid factors, including surgery, or discharge diagnosis on the changes in Hgb or Epo requirements. However, patients who required a blood transfusion during the hospitalization had lower Hgb levels and higher Epo doses both prior to and after hospitalization, as well as lower Hgb trough levels. In addition, females had lower Hgb levels than males both prior to and after hospitalization, and were receiving a higher Epo dose 191 +/- 18 vs. 129 +/- 20 U/kg/week at 1 month and 215 +/- 18 U/kg/week vs. 134 +/- 22, p < 0.005 at 2 months after hospitalization. CONCLUSION: This study points out that hemodialysis patients experience a significant and prolonged decrease in Hgb levels after hospitalization, even despite a moderate increase in Epo dosing.     

Recombinant human erythropoietin and phlebotomy in the treatment of iron overload in chronic hemodialysis patients

Five long-term hemodialysis patients with clinical iron overload were treated with 300 U/kg of recombinant human erythropoietin (rHuEPO) intravenously (IV) after each hemodialysis. The patients were phlebotomized after each hemodialysis at any time the predialysis hematocrit was 35% or greater. Over a period of 1 year, the average phlebotomy rate varied from 0.5 to 1.1 U/wk with a mean phlebotomy rate of 45.8 +/- 5.6 U/yr (range, 27 to 57 U). The mean serum ferritin decreased from 8,412 +/- 1,599 micrograms/L (ng/mL) to 3,007 +/- 1,129 micrograms/L (ng/mL), and the mean iron removal over this period was 9.5 g. Liver iron deposition, as measured by density on computed tomographic (CT) scan, improved, while skin color lightened significantly. Patients tolerated phlebotomy with no major symptoms or complications and exhibited no change in the hemogram or serum chemistries. In patients with severe iron overload, changes in serum ferritin with erythropoietin treatment alone may not reflect true change in iron burden. Use of high-dose erythropoietin and phlebotomy is an effective and safe (at least for 1 year) method of reducing iron overload in long-term hemodialysis patients.     

Serial ferritin concentrations in hemodialysis patients receiving intravenous iron

BACKGROUND: Treatment of the anemia of chronic renal failure with intravenous iron and erythropoietin is highly effective, but frequently leads to ferritin levels which are much higher than those seen in the general population. High ferritin concentrations raise concern about the potential toxicity of increased body iron stores. PATIENTS AND METHODS: We retrospectively evaluated parameters of iron metabolism over a 4-year period among all our chronic hemodialysis patients who had been receiving intravenous iron and erythropoietin. Initially, patients received intermittent infusions of 300 mg intravenous iron x 3 doses for a low ferritin or low percent saturation of total iron binding capacity (TIBC), but this protocol was subsequently changed to weekly or biweekly infusions of 50-100 mg. RESULTS: We observed an improvement in average hemoglobin values, modest increases in serum iron and saturation of iron binding capacity, and a 125% increase in ferritin levels over 4 years. TIBC decreased. Overall, ferritin values increased 79 microg/l for each 1% increase in TIBC saturation. Ten patients with ferritin concentration greater than 1,000 pg/l received a three month course of vitamin C with no decline in the ferritin concentration. CONCLUSION: Current protocols for iron delivery may result in progressive increases in ferritin levels. Concern about the risks of iron overload should temper the quantity of iron used in dialysis programs.     

Treatment of Iron Deficiency Anemia in Orthopedic Surgery with Intravenous Iron: Efficacy and Limits: A Prospective Study

Background: Preoperative anemia is frequent in patients undergoing orthopedic surgery. The purpose of this study was to assess the preoperative increase of hemoglobin in iron deficiency anemia patients treated with intravenous iron.

Methods: After obtaining written informed consent, 20 patients with iron deficiency anemia received 900 mg intravenous iron sucrose over 10 days starting 4 weeks before surgery. Changes of hemoglobin and iron status were measured over 4 weeks and at discharge. In the last 11 patients, endogenous erythropoietin was also measured. Data were analyzed using the Friedman test followed by pairwise Wilcoxon signed rank tests with Bonferroni correction.

Results: Hemoglobin increased significantly (P < 0.0001) after intravenous iron treatment. Overall, the mean maximum increase was 1.0 +/- 0.6 g/dl (range, 0.2-2.2 g/dl). Ferritin increased from 78 +/- 70 to 428 +/- 191 [mu]g/l (P = 0.0001), ferritin index decreased from 2.7 +/- 2.4 to 1.5 +/- 1.0 (P = 0.0001), and soluble transferrin receptor decreased from 4.1 +/- 2.3 mg/l to 3.7 +/- 2.3 mg/l (P = 0.049), whereas transferrin saturation (20.5 +/- 9.0 to 22.9 +/- 9.0%) and serum iron (13.3 +/- 4.6 to 13.1 +/- 4.5 [mu]m) did not change significantly after intravenous iron treatment. Endogenous erythropoietin decreased from 261 +/- 130 pg/ml to 190 +/- 49 pg/ml 2 weeks after intravenous iron treatment (P = 0.050, not significant after Bonferroni correction). No adverse events related to intravenous iron were observed. The maximum increase of hemoglobin was observed 2 weeks after the start of intravenous iron treatment, indicating that administration of intravenous iron 2-3 weeks before surgery may be optimal.     

Effect of weekly or successive iron supplementation on erythropoietin doses in patients receiving hemodialysis

AIMS: To conduct a 3-month prospective study to determine the optimal way for intravenous iron supplementation in hemodialysis (HD) patients with resistance to recombinant human erythropoietin (rHuEPO) therapy due to deficient iron storage. METHODS: Thirty-five HD patients with iron deficiency were divided into three groups: (1) patients receiving an intravenous infusion of 40 mg of iron during the first ten HD sessions (n = 12); (2) patients receiving 40 mg of iron injected once a week for 10 weeks (n = 12), and (3) patients without any iron supplementation (n = 11). The rHuEPO dosage was adjusted to maintain hemoglobin levels >10.0 g/dl, and the degree of anemia was assessed 3 months later. RESULTS: In group 1, the hemoglobin levels were significantly increased after 4 weeks and remained increased until the end of the study (p < 0.01). In group 2, the hemoglobin levels were gradually increased until the end of the study (p < 0.01). There was no difference in the final hemoglobin values between both groups. The rHuEPO dosage was significantly decreased from 131 +/- 18 to 90 +/- 17 U/kg/week in group 1 (p < 0.01), but could not be changed in group 2 during the observation period despite a similar elevation of the serum ferritin level. In group 3, the rHuEPO doses were rather increased at the end of the study (p < 0.05). CONCLUSION: Aggressive iron supplementation for the short term may be effective to restore rHuEPO hyporesponsiveness in HD patients with functional iron deficiency.     

Content of reticulocyte hemoglobin is a reliable tool for determining iron deficiency in dialysis patients

BACKGROUND: The evaluation of iron status in dialysis patients provides information essential to the planning of adequate recombinant human erythropoietin (rHuEPO) treatment. Iron status of the patients can be determined from the recently available measurement of content of reticulocyte hemoglobin (CHr). METHODS: In this study, to clarify the accuracy of CHr in diagnosing iron deficiency in hemodialysis (HD) patients, we initially compared CHr with such conventional iron parameters as serum ferritin levels, transferrin saturation and serum soluble transferrin receptor levels. Secondly, we investigated the changes in CHr during iron supplementation for iron-deficient patients to determine whether this marker is a prospective and reliable indicator of iron sufficiency. The participants in this study were 149 hemodialysis (HD) patients and 53 age-matched healthy subjects. Iron deficiency was defined as having a TSAT of less than 20% and serum ferritin of less than 100 ng/ml. Conventional parameters of red blood cells and CHr were measured by an ADVIA120 autoanalyzer. RESULTS: Mean CHr was 32.3 +/- 2.2 pg in the patients undergoing hemodialysis treatment. CHr significantly correlated with iron parameters in the dialysis patients. Logistic regression analysis was performed to determine the relationship between CHr and each outcome measure, and CHr was the significant multivariate predictor of iron deficiency. Iron supplements given to the patients with low CHr and hematocrit (Hct) significantly increased Hct, resulting in a decrease in the weekly dosage of rHuEPO. CONCLUSIONS: CHr, measured simultaneously with Hct, is a sensitive and specific marker of iron status in dialysis patients.     

Ascorbic acid does not augment the restoration effect of iron treatment for empty iron stores in patients after gastrointestinal surgery

The effect of a 6-week combined treatment with ferrous sulfate (80 mg Fe++ three times daily) and ascorbic acid (75 mg three times daily) on the empty iron stores in 20 patients after gastrointestinal surgery was examined from changes of serum ferritin. One group of 20 patients with similar clinical characteristics served as controls. The treatment replaced the empty iron stores. Since mean serum ferritin concentrations increased from 9 +/- 8 to 29 +/- 11 micrograms/l (P less than 0.001) in males and from 8 +/- 8 to 26 +/- 10 micrograms/l (P less than 0.001) in the females. Also blood hemoglobin and serum iron concentrations increased significantly (P less than 0.01). Among the controls there were no marked changes in serum ferritin, blood hemoglobin or serum iron concentrations. However, the increase of serum ferritin caused by this combined treatment was similar with that caused previously by pure ferrous sulfate treatment. Thus, it is considered that the combined treatment with ferrous sulfate (80 mg Fe++ three times daily) and ascorbic acid (75 mg three times daily) restores the empty iron stores in patients after gastrointestinal surgery, but that the increase is not augmented by the ascorbic acid. Thus, a pure iron therapy is recommended to fill up the empty iron stores in these patients.     

The effect of an iron supplement on serum aluminum level and desferrioxamine mobilization test in hemodialysis patients.

BACKGROUND: The serum aluminum (Al) measurement with desferrioxamine (DFO) mobilization is a screening test for uremic patients with an Al overload. In these patients, body iron status is one of the factors affecting the serum Al level. This study is designed to elucidate the effects of iron supplements on the serum Al and the DFO mobilization test. METHODS: Our study featured ten hemodialysis patients with iron deficiency anemia. The iron supplement was given intravenously with saccharated ferric oxide, 40 mg three times weekly, at the end of each hemodialysis. The total amount of iron supplement was 1,000 mg. All the patients underwent a DFO test at a dose of 5 mg/kg. The same test was repeated two weeks after completion of the iron supplement. RESULTS: After the iron supplement, patients' iron deficiency anemia improved with a serum ferritin elevation from 312.4 +/- 589.5 to 748.2 +/- 566.2 microg/L (p < 0.01), and iron saturation from 21.6 +/- 20.3 to 41.1 +/- 21.7% (p = 0.06). The basal serum Al level decreased from 34.3 +/- 13.8 to 21.8 +/- 8.5 microg/L (p = 0.01). In the DFO mobilization test, the peak serum Al level decreased from 63.4 +/- 19.3 to 50.7 +/- 20.5 microg/L (p < 0.01). The amount of Al increment (deltaAl) in DFO test was not changed (29.1 +/- 12.0 vs. 28.9 +/- 15.9 microg/L, p = 0.86). The change in basal Al level tended to negatively correlate with the percentage of increment in iron saturation (r = -0.628, p = 0.05). CONCLUSION: Results in this study suggest that iron supplements may significantly reduce the basal serum Al and peak Al in DFO mobilization test, without significant change of the mean deltaAl. The data presented indicate that in the interpretation of serum aluminum levels the iron status should be taken into account.