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

C-reactive protein concentrations are higher in dogs with stage IV chronic kidney disease treated with intermittent hemodialysis

In chronic kidney disease dogs, the inflammatory process increases C-reactive protein concentrations. This study aimed to determine C-reactive protein serum concentrations in stage IV chronic kidney disease dogs treated with intermittent hemodialysis. A prospective cohort study was conducted with 23 dogs allocated into three groups: control group (CG, n = 7), intermittent hemodialysis group (IHG, n = 8) and clinical treatment group (CTG, n = 8), both comprised of stage IV chronic kidney disease dogs. One blood sample from CG (initial evaluation) and two samples from IHG and CTG (first- and last-moment) were obtained to determine C-reactive protein concentration, total leukocytes, platelets, erythrocytes, total plasma protein, serum albumin, urea, creatinine, and phosphorus. C-reactive protein was higher in IHG compared to CG in the first- and last-moments (p <0.001) and compared to CTG in the first-moment (p = 0.0406). C-reactive protein presented moderate positive correlation with leukocytes (r = 0.5479; p = 0.01), and moderate negative correlation with albumin (r = - 0.5974; p = 0.006) and red blood cells (r = - 0.5878, p = 0.01). A high correlation coefficient was observed in the tests’ evaluation (CI = 0.59–0.78; r = 0.70; P<0.0001). In conclusion, both assays used in this study to measure C-reactive protein have provided safe and reliable quantification of the results. Additionally, despite IHG dogs presented an active inflammatory profile, intermittent hemodialysis has proven to be beneficial, leading to a clinical improvement in life quality of patients, and thus being recommended for stage IV CKD dogs when performed by trained professionals.

Ineffective Erythropoietin Response to Anemia in Sepsis

Background: To determine whether degree of anemia at sepsis onset is predictive of inflammatory cytokine trajectory, erythropoietin response, and recovery. Patients and Methods: Critically ill patients with sepsis were stratified into three groups based on initial hemoglobin (Hgb): Hgb <8 g/dL (severe); 8-10 g/dL (moderate); and >10 g/dL (mild). Granulocyte colony stimulating factor (G-CSF), interferon (IFN)-γ, tumor necrosis factor (TNF)-α, C-reactive protein (CRP), erythropoietin (EPO), and Zubrod scores were measured serially. Results: Thirty-four percent had severe anemia (Hgb, 7.2 ± 0.7g/dL), 35% had moderate anemia (Hgb, 9.1 ± 0.6g/dL), and 31% had mild anemia (Hgb, 11.3 ± 1.1g/dL). All groups experienced persistently high EPO levels without resolution of anemia. IFN-γ and CRP was persistently elevated in all groups. At three, six, and 12 months, the severe anemia group had higher Zubrod scores. Conclusions: Degree of anemia at sepsis onset was not associated with a difference in proinflammatory cytokine trajectory but was associated with a worse functional outcome. Despite initial elevated EPO levels, it did not correlate with resolution of anemia.

Managing Anemia across the Stages of Kidney Disease in Those Hyporesponsive to Erythropoiesis-Stimulating Agents

BACKGROUND

Patients with CKD frequently have anemia that results from iron-restricted erythropoiesis and inflammation. Anemia of CKD is currently managed with iron supplements and erythropoiesis-stimulating agents (ESAs) to promote erythropoiesis and with RBC transfusion in severe cases. Hyporesponse to ESAs, or the need for larger than usual doses to attain a given hemoglobin (Hb) level, is associated with increased morbidity and mortality and presents a pressing clinical challenge, particularly for patients on dialysis. This paper reviews ESA hyporesponse and potential new therapeutic options in the management of anemia of CKD.

SUMMARY

The most common causes of ESA hyporesponse include iron deficiency and inflammation, and to a lesser degree, secondary hyperparathyroidism, inadequate dialysis, malnutrition, and concomitant medications. Management of ESA hyporesponse is multipronged and involves treating low level infections, ensuring adequate nutrition, and optimizing iron status and dialysis modality, although some patients can remain refractory. Inflammation directly increases production and secretion of hepcidin, contributes to an impaired response to hypoxia, and suppresses proliferation of erythroid progenitors. Coordination of renal and hepatic erythropoietin (EPO) production and iron metabolism is under the control of hypoxia-inducible factors (HIF), which are in turn regulated by HIF-prolyl hydroxylases (HIF-PHs). HIF-PHs and hepcidin are therefore attractive potential drug targets particularly in patients with ESA hyporesponse. Several oral HIF-PH inhibitors have been evaluated in patients with anemia of CKD and have been shown to increase Hb and reduce hepcidin regardless of inflammation, iron status, or dialysis modality. These sustained effects are achieved through more modest increases in endogenous EPO compared with ESAs. Key Messages: Treatments that address ESA hyporesponse remain a significant unmet clinical need in patients with anemia of CKD. New therapies such as HIF-PH inhibitors have the potential to address fundamental aspects of ESA hyporesponse and provide a new therapeutic option in these patients.

Factors associated with hepcidin-25 levels in maintenance hemodialysis patients

This study aimed to investigate the factors that are independently associated with hepcidin-25 and its relationship with doses of erythropoiesis-stimulating agents (ESAs) and intravenous iron in stable maintenance hemodialysis patients (smHD) stratified by ESAs administration. In 103 adult smHD (ESAs therapy (N = 64) and ESAs-free (N = 39)), median values of biologically active hepcidin-25 (chemiluminescent direct ELISA assay) and ferritin levels were significantly higher whereas red blood cell count, hemoglobin, and hematocrit values were lower in ESAs therapy compared to ESAs-free group (P < .001, for all). Our results suggest that ESAs-independent smHD exhibit supposedly normal hepcidin-25 levels and preserved iron homeostasis, with a lower degree of anemia. The results of our multivariable model indicate that hepcidin-25 levels are independently and positively associated with iron stores and inflammation, and inversely with active erythropoiesis, regardless of ESAs administration. Maintenance ESAs and the intravenous iron dose were not related to hepcidin-25 levels.

A pharmacist-managed dosing algorithm for darbepoetin alfa and iron sucrose in hemodialysis patients: A randomized, controlled trial

The attainment of target hemoglobin levels in hemodialysis patients is low. Several factors play a role, such as hyporesponsiveness to erythropoiesis-stimulating agents (ESA), but also suboptimal prescribing of ESA and iron. The goal of this study was to investigate if a pharmacist-managed dosing algorithm for darbepoetin alfa (DA) and iron sucrose improves the attainment of target hemoglobin levels. In this randomized controlled trial, 200 hemodialysis patients from a Dutch teaching hospital were included. In the intervention group (n = 100), a pharmacist monthly provided dose recommendations for DA and iron sucrose based on dosing algorithms. The control group (n = 100) received usual care. In the intervention group, the percentage per patient within the target range (PTR) for hemoglobin (target range 6.8-7.4 mmol/L) and iron status was higher than in the control group (for hemoglobin median 38.5% vs 23.1%, P = .001 and for iron status median 21.1% vs 8.3%, P = .003). The percentage of high hemoglobin levels (>8.1 mmol/L) was lower in the intervention group (median 0.0% vs 7.7%, P = .034). The weekly dose of DA was lower in the intervention group (median 34.0 vs 46.9 mcg, P = .020), whereas iron dose was higher (median 75 vs 0 mg). No difference was found for the percentage of hemoglobin levels below the target range. In conclusion, a pharmacist-managed dosing algorithm for DA and iron sucrose increased the attainment of target levels for hemoglobin and iron status, reduced the percentage of high hemoglobin levels, and was associated with a lower DA and a higher iron sucrose dose.

Neutrophil Elastase Inhibitors and Chronic Kidney Disease

End-stage renal disease (ESRD), the last stage of chronic kidney disease (CKD), is characterized by chronic inflammation and oxidative stress. Neutrophils are the front line cells that mediate an inflammatory response against microorganisms as they can migrate, produce reactive oxygen species (ROS), secrete neutrophil serine proteases (NSPs), and release neutrophil extracellular traps (NETs). Serine proteases inhibitors regulate the activity of serine proteases and reduce neutrophil accumulation at inflammatory sites. This review intends to relate the role of neutrophil elastase in CKD and the effects of neutrophil elastase inhibitors in predicting or preventing inflammation.

Epoetin alfa resistance in hemodialysis patients with chronic kidney disease: a longitudinal study

Anemia is an inevitable complication of hemodialysis, and the primary cause is erythropoietin deficiency. After diagnosis, treatment begins with an erythropoiesis-stimulating agent (ESA). However, some patients remain anemic even after receiving this medication. This study aimed to investigate the factors associated with resistance to recombinant human erythropoietin therapy with epoetin alfa (αEPO). We performed a prospective, longitudinal study of hemodialysis patients receiving treatment with αEPO at our reference hospital from July 2015 to June 2016. Clinical data was collected, and the response to αEPO treatment was evaluated using the erythropoietin resistance index (ERI). The ERI was defined as the weekly weight-adjusted αEPO dose (U/kg per week)/hemoglobin level (g/dL). A longitudinal linear regression model was fitted with random effects to verify the relationships between clinical and laboratory data and ERI. We enrolled 99 patients (average age, 45.7 (±17.6) years; male, 51.5%; 86.8% with hypertension). The ERI showed a significant positive association with serum ferritin and C-reactive protein, percentage interdialytic weight gain, and continuous usage of angiotensin receptor blocker (ARB) hypertension medication. The ERI was negatively associated with serum iron and albumin, age, urea reduction ratio, and body mass index. Our findings indicate that resistance to αEPO was related to a low serum iron reserve, an inflammatory state, poor nutritional status, and continuous usage of ARBs.

Proteogenomic studies on cancer drug resistance: towards biomarker discovery and target identification

INTRODUCTION

Chemoresistance is a major obstacle for current cancer treatment. Proteogenomics is a powerful multi-omics research field that uses customized protein sequence databases generated by genomic and transcriptomic information to identify novel genes (e.g. noncoding, mutation and fusion genes) from mass spectrometry-based proteomic data. By identifying aberrations that are differentially expressed between tumor and normal pairs, this approach can also be applied to validate protein variants in cancer, which may reveal the response to drug treatment. Areas covered: In this review, we will present recent advances in proteogenomic investigations of cancer drug resistance with an emphasis on integrative proteogenomic pipelines and the biomarker discovery which contributes to achieving the goal of using precision/personalized medicine for cancer treatment. Expert commentary: The discovery and comprehensive understanding of potential biomarkers help identify the cohort of patients who may benefit from particular treatments, and will assist real-time clinical decision-making to maximize therapeutic efficacy and minimize adverse effects. With the development of MS-based proteomics and NGS-based sequencing, a growing number of proteogenomic tools are being developed specifically to investigate cancer drug resistance.