The relationship of Prohepcidin levels with anemia and inflammatory markers in non-diabetic uremic patients: a controlled study

Impact of Inflammation on Ferritin, Hepcidin and the Management of Iron Deficiency Anemia in Chronic Kidney Disease

Iron deficiency anemia (IDA) is a major problem in chronic kidney disease (CKD), causing increased mortality. Ferritin stores iron, representing iron status. Hepcidin binds to ferroportin, thereby inhibiting iron absorption/efflux. Inflammation in CKD increases ferritin and hepcidin independent of iron status, which reduce iron availability. While intravenous iron therapy (IIT) is superior to oral iron therapy (OIT) in CKD patients with inflammation, OIT is as effective as IIT in those without. Inflammation reduces predictive values of ferritin and hepcidin for iron status and responsiveness to iron therapy. Upper limit of ferritin to predict iron overload is higher in CKD patients with inflammation than in those without. However, magnetic resonance imaging studies show lower cutoff levels of serum ferritin to predict iron overload in dialysis patients with apparent inflammation than upper limit of ferritin proposed by international guidelines. Compared to CKD patients with inflammation, optimal ferritin levels for IDA are lower in those without, requiring reduced iron dose and leading to decreased mortality. The management of IDA should differ between CKD patients with and without inflammation and include minimization of inflammation. Further studies are needed to determine the impact of inflammation on ferritin, hepcidin and therapeutic strategy for IDA in CKD.

Optimal Serum Ferritin Levels for Iron Deficiency Anemia during Oral Iron Therapy (OIT) in Japanese Hemodialysis Patients with Minor Inflammation and Benefit of Intravenous Iron Therapy for OIT-Nonresponders

Background: We determined optimal serum ferritin for oral iron therapy (OIT) in hemodialysis (HD) patients with iron deficiency anemia (IDA)/minor inflammation, and benefit of intravenous iron therapy (IIT) for OIT-nonresponders. Methods: Inclusion criteria were IDA (Hb <120 g/L, serum ferritin <227.4 pmol/L). Exclusion criteria were inflammation (C-reactive protein (CRP) ≥ 5 mg/L), bleeding, or cancer. IIT was withheld >3 months before the study. ΔHb ≥ 20 g/L above baseline or maintaining target Hb (tHB; 120-130 g/L) was considered responsive. Fifty-one patients received OIT (ferrous fumarate, 50 mg/day) for 3 months; this continued in OIT-responders but was switched to IIT (saccharated ferric oxide, 40 mg/week) in OIT-nonresponders for 4 months. All received continuous erythropoietin receptor activator (CERA). Hb, ferritin, hepcidin-25, and CERA dose were measured. Results: Demographics before OIT were similar between OIT-responders and OIT-nonresponders except low Hb and high triglycerides in OIT-nonresponders. Thirty-nine were OIT-responders with reduced CERA dose. Hb rose with a peak at 5 months. Ferritin and hepcidin-25 continuously increased. Hb positively correlated with ferritin in OIT-responders (r = 0.913, p = 0.03) till 5 months after OIT. The correlation equation estimated optimal ferritin of 30-40 ng/mL using tHb (120-130 g/L). Seven OIT-nonresponders were IIT-responders. Conclusions: Optimal serum ferritin for OIT is 67.4-89.9 pmol/L in HD patients with IDA/minor inflammation. IIT may be a second line of treatment for OIT-nonreponders.

Effect of peritoneal dialysis versus hemodialysis on renal anemia in renal in end-stage disease patients: a meta-analysis

The aim of this meta-analysis was to evaluate the effect of peritoneal dialysis (PD) and hemodialysis (HD) on renal anemia (RA) in renal disease patients by a meta-analysis. Relevant studies published before June 2015 were searched. Pooled odds ratio (OR) with 95% confidence interval (CI) was used to evaluate the effect of HD and PD on RA based on five indexes: hemoglobin, ferritin, transferrin saturation index, serum albumin, and parathyroid hormone. Sensitivity analysis and publication bias assessment were conducted to evaluate the stability and reliability of our results. A total of fourteen eligible studies with 1103 cases underwent HD and 625 cases underwent PD were used for this meta-analysis. There were no significant difference for levels of hemoglobin (SMD = -0.23, 95% CI: -0.74 to 0.28), ferritin (SMD = 0.01, 95% CI: -0.59 to 0.62), parathyroid hormone (SMD = 0.11, 95% CI: -1.53 to 1.75) and transferrin saturation index (SMD = -0.06, 95% CI: -0.67 to 0.56) between HD and PD group. However, the content of serum albumin in HD group was much more than that in PD group (SMD = 1.58, 95% CI: 0.35 to 2.81). Neither of the included studies could reverse the pooled side effect and Egger's test demonstrated no publication bias. Both of the two dialysis strategies have a similar effect on RA in renal disease patients.

Management of anemia in patients with diabetic kidney disease: A consensus statement

This consensus statement focuses on the window of opportunity, which exists while treating patients with diabetic kidney disease and anemia.

C-reactive protein but not hepcidin, NGAL and transferrin determines the ESA resistance in hemodialysis patients

BACKGROUND

Erythropoiesis-stimulating agents (ESA) are commonly used for the treatment of anemia in hemodialysis (HD) patients, however, 5-10% of these patients have resistance to ESA treatment. Hepcidin and neutrophil-gelatinase associated lipocalin (NGAL) are induced by inflammation and these proteins may take role in ESA resistance. Herein, we aimed to investigate the effects of serum hepcidin, NGAL, transferrin and C-reactive protein (CRP) levels on ESA resistance in HD patients.

METHODS

A total of 63 chronic HD patients (6.0 ± 17 years, M/F:44/19) and 20 healthy controls (6.0 ± 4 years, M/F:14/6) were enrolled. ESA resistance index (ERI) was calculated as weekly ESA dose (IU)/body weight (kg)/hemoglobin level (g/dL). Patients on ESA treatment were divided into two groups depending on the median ERI value as low and high ERI groups.

RESULTS

Serum ferritin, hepcidin and NGAL levels were significantly higher in HD patients compared with controls. Serum transferrin levels were lower in high ESA index group compared with patients without ESA treatment and healthy controls. ERI was significantly correlated with serum CRP levels (r = 0.55, p < 0.001). In HD patients, serum hepcidin levels were associated with ferritin (r = 0.55, p < 0.01) and creatinine (r = 0.27, p = 0.03). Dose of ESA was significantly associated with serum CRP (r = 0.34, p = 0.02), total protein (r = -0.34, p = 0.01), transferrin (r = -0.28, p = 0.04) and ferritin (r = 0.31, p = 0.02). In linear regression analysis to predict ERI, age, gender, serum CRP, hepcidin, NGAL, albumin, ferritin and BMI were included (Model R = 0.62, R(2) =0 .38, p = 0.02). Serum CRP was the only significant factor predicting ERI.

CONCLUSION

CRP was the only predictor of ESA resistance index in HD patients. Hepcidin, NGAL and transferrin were not found to be markers of ESA resistance.