Recombinant Human Erythropoietin Therapy Research Articles

Pattern of Monthly Percentage of Hemodialysis Children Achieving the KDIGO Recommended Hemoglobin Targets: A Twelve-Month Prospective Study to Assess the Trend of Anemia

Abstract Background Anemia is one of the common problems in children on maintenance hemodialysis (HD). It leads to poor quality of life and when severe, it is associated with cardiovascular dysfunction, cardiomyopathy, and death. Proper treatment of anemia in these patients results in better physical and mental performance. So, our study aimed to assess the trend of anemia among HD children by following the monthly percentage of patients capable of achieving Hb level between 11-12g/dl. Methods For optimum treatment of anemia, the Kidney Disease Improving Global Outcomes (KDIGO) guidelines (2012) recommended to measure Hb every month in HD children targeting monthly Hb concentration of 11-12 g/dl. So, we conducted this 12-months prospective study to assess the trend of anemia among HD children at Pediatric Dialysis Unit of Ain Shams University by following the monthly percentage of patients capable of achieving Hb level between 11-12g/dl. Results This study was done over 12 month-period from April 1st, 2020, till March 31st, 2021. A total of 78 patients were included with a mean age at the time of enrollment in the study of 12.16 ± 3.3 years. They were 45 (57.7%) males and 33 (42.3%) females. All patients were receiving 3 hours every other day HD session for 3 sessions a week with a HD duration range of 3.0 - 140.88 months and a median of 16.51 months. All patients were receiving proper doses of recombinant human erythropoietin (rHuEPO) and intravenous iron therapy. Our study showed that the monthly reported percentages of patients achieved Hb level between 11-12g/dl ranged from 14.7% to 40.8% and that of patients with Hb level <11g/dl ranged between 51.4 – 73.5%. It also revealed statistical evidence of significant association between the presence of anemia in our patients at the time of enrollment in the study and HD durations < 6 months (p < 0.05). Conclusion Despite proper HD treatment and proper doses of recombinant human erythropoietin (rHuEPO) and intravenous iron therapy, anemia is still a prevalent problem among our HD children.

Short-term effect of low-dose roxadustat combined with erythropoiesis-stimulating agent treatment for erythropoietin-resistant anemia in patients undergoing maintenance hemodialysis.

Erythropoietin resistance is present in some patients with chronic kidney disease, especially in those undergoing hemodialysis, and is often treated using roxadustat rather than iron supplements and erythropoiesis-stimulating agents (ESAs). However, some patients cannot afford full doses of roxadustat. This retrospective study investigated the efficacy of low-dose roxadustat combined with recombinant human erythropoietin (rhuEPO) therapy in 39 patients with erythropoietin-resistant renal anemia undergoing maintenance hemodialysis (3-4 sessions/week). The ability of the combination of low-dose roxadustat and rhuEPO to increase the hemoglobin concentration over 12 weeks was assessed. Markers of iron metabolism were evaluated. Eligible adults received 50-60% of the recommended dose of roxadustat and higher doses of rhuEPO. The mean hemoglobin level increased from 77.67 ± 11.18 g/dL to 92.0 ± 8.35 g/dL after treatment, and the hemoglobin response rate increased to 72%. The mean hematocrit level significantly increased from 24.26 ± 3.99% to 30.04 ± 3.69%. The soluble transferrin receptor level increased (27.29 ± 13.60 mg/L to 38.09 ± 12.78 mg/L), while the total iron binding capacity (49.22 ± 11.29 mg/L to 43.91 ± 12.88 mg/L) and ferritin level (171.05 ± 54.75 ng/mL to 140.83 ± 42.03 ng/mL) decreased. Therefore, in patients with ESA-resistant anemia who are undergoing hemodialysis, the combination of low-dose roxadustat and rhuEPO effectively improves renal anemia and iron metabolism.

Positive response of a hemodialysis patient with pure red cell aplasia on recombinant human erythropoietin therapy to cyclosporine and Roxadustat.

Recombinant human erythropoietin (rHuEPO) is commonly used to treat anemia associated with chronic kidney disease (CKD). EPO-induced Pure Red Cell Aplasia (PRCA) is a rare condition of profound anemia with EPO treatment. Upon finding the development of EPO-induced PRCA, the treatment requires immediate withdrawal of EPO therapy and initiate new treatments with immunosuppression or renal transplantation. Anti-EPO antibody assay is not always positive in EPO-induced PRCA. Here, we report a case on the sudden development of PRCA in a hemodialysis patient receiving EPO and how we treated the condition successfully with cyclosporine and subsequently maintained the hemoglobin with Roxadustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI). Even though the anti-EPO antibody was negative by Enzyme Linked Immunosorbent Assay (ELISA) in our case, the clinical course, the markedly reduced reticulocyte count < 10,000/μL, the bone marrow (BM) biopsy revealing reduced erythroblasts, and its subsequent response to cyclosporine, were similar to EPO-induced PRCA. The clinical picture of EPO-induced PRCA, the limitation of the EPO-neutralizing antibody (Ab) assay, and treatment strategies were discussed.

Intravenous iron and erythropoietin therapy for postoperative anemia among orthopedic surgery patients

BackgroundPostoperative anemia is a risk factor for adverse surgical outcomes. Our study aimed to assess the role of intravenous iron and erythropoietin therapy for the rapid correction of anemia following orthopedic surgery.MethodsPatients undergoing elective orthopedic surgery were prospectively enrolled and randomly divided into three groups: Control (placebo), Group 1 (IV iron monotherapy), and Group 2 [combined IV iron and recombinant human erythropoietin (rHuEPO) therapy]. Blood tests were performed preoperative (baseline) and on postoperative days (PODs) 1, 3, and 7.ResultsAll groups demonstrated significantly lower hemoglobin (Hb) concentrations compared to baseline, with no significant inter-group differences in postoperative Hb concentrations (p > 0.05). Serum erythropoietin, ferritin, and vitamin B12 levels, and reticulocyte count increased beyond normal ranges in all groups. Significantly lower serum iron levels were observed postoperatively in all groups (p < 0.05). No significant inter-group differences in hepcidin level were observed (p > 0.05).ConclusionPostoperative treatment with combined intravenous iron and rHuEPO was ineffective in correcting postoperative anemia among orthopedic surgery patients, besides achieving higher reticulocyte counts in the first week of surgery. No improvement in mobilization of storage iron was achieved with rHuEPO. We further suggest against vitamin B12 administration during the early postoperative period.

The effectiveness of umbilical cord milking/ delayed cord clamping and recombinant human erythropoietin in reducing red blood cell transfusions in extremely and very low birth weight infants

Anemia of prematurity is one of the most common and serious problems of neonatology. The main focus is to prevent of anemia in preterm infants. The aim of the study was to assess effectiveness of umbilical cord milking/delayed cord clamping and erythropoietin therapy in reducing red blood cell transfusions in extremely and very low birth weight infants. This clinical study was approved by the Commission on ethics of biomedical research (Protocol No. 12 November 17, 2016) and approved by the Scientific Council of National Medical Research Center for obstetrics, gynecology and perinatology named academician V.I. Kulakov of the ministry of Healthcare of the Russian Federation (Protocol No. 19 of November 29, 2016). Analysis of 482 extremely and very low birth weight infants was conducted (from 2008 to 2018). Umbilical cord milking or delayed umbilical cord clamping, both, and in combination with recombinant human erythropoietin therapy, decreasing the phlebotomy losses significantly reduces the need for transfusions of red blood cells in extremely and very low birth weight infants. The effectiveness of erythropoietin therapy, time of its start and various treatment schemes remain controversial, therefore further researches are necessary.

Haematological Indicators of Response to Erythropoietin Therapy in Chronic Renal Failure Patients on Haemodialysis: Impact of Angiotensin-Converting Enzyme rs4343 Gene Polymorphism.

PurposeThis is the first cross-sectional study studying the changes in haematological indicators of the response to recombinant human erythropoietin (rHuEPO) therapy in chronic renal failure (CRF) patients on haemodialysis (HD) stratified according to ACE G2350A (rs4343) gene polymorphism.DesignAn observational cross-sectional study.SettingNephrology department and Biochemistry and molecular biology department, faculty of medicine, Cairo University.PatientsA total of 256 CRF patients on HD for at least six months (162 male and 103 female) and 160 healthy subjects (122 male and 38 female) were recruited in the current study after signing a consent form. ACE G2350A (rs4343) Insertion/Deletion (I/D) was tested, the association between ACE G2350A (RS4343) gene polymorphisms and patients response to rHuEpo was evaluated.ResultsACE G2350A (rs4343) I/D was the most prevalent genotype, while I/I genotype was the lowest prevalent among patient or control subjects included in the study. D allele is the most prevalent allele, either among patients or the control group. Hemoglobin (Hb) level in patients with I/I and Deletion/Deletion (D/D) genotype was significantly higher compared to those with I/D genotype (P = 0.012 and P = 0.005, respectively). Serum iron in the I/D genotype was significantly higher than those with either I/I or D/D genotype (P = 0.045 and P = 0.018, respectively). Angiotensin-converting enzyme (ACE) content, total leukocytic count (TLC), and soluble erythropoietin receptor (sEpoR) were independent predictors of Hb level. The ACE gene, TLC, and serum iron were the independent factors that may affect the Haematocrit (Hct) level. ACE G2350A (rs4343) gene polymorphisms may affect the HD patient’s responses to rHuEPOs.ConclusionIn HD patients, screening for ACE G2350A (rs4343) gene polymorphisms before rHuEpo administration may help predict patient response.

High Prevalence of Iron Deficiency Despite Standardized High-Dose Iron Supplementation During Recombinant Erythropoietin Therapy in Extremely Low Gestational Age Newborns

To assess the effects of protocolized recombinant human erythropoietin (r-HuEPO) therapy and standardized high dose iron supplementation on hematologic and iron status measures in a cohort of extremely low gestational age newborns (ELGANs). Charts of extremely low gestational age newborns admitted from 2006 to 2016 and who had received r-HuEPO per neonatal intensive care unit protocol were reviewed. The r-HuEPO was started at a dose of 900 IU/kg per week after 7days of age and continued until 35weeks postmenstrual age. Oral iron supplementation at 6-12mg/kg per day was used to maintain a transferrin saturation of >20% during r-HuEPO treatment. Data on demographic features, hematologic and iron panel indices, red blood cell transfusions, and clinical outcomes were collected. Quartile groups were created based on serum ferritin levels at the conclusion of the r-HuEPO treatment and the quartiles were compared. The cohort included 116 infants with mean gestational age 25.8±1.5weeks and birth weight 793±174.1g. The r-HuEPO promoted erythropoiesis as indicated by increasing hemoglobin, hematocrit, and reticulocyte count. Serum ferritin decreased over time and was ≤75ng/mL in 60.2% of infants at the conclusion of r-HuEPO therapy; 87% received packed red blood cell transfusions. Transfusion volume, total iron intake, total iron binding capacity, and transferrin concentration differed among infants in the different serum ferritin quartiles (P<.05). In extremely low gestational age newborns, r-HuEPO therapy promoted erythropoiesis. Despite a biomarker-based standardized high-dose iron supplementation, the majority of infants had evidence of iron deficiency to a degree that is associated with reduced brain function.

The recombinant human erythropoietin therapy for extremely and very low birth weight infants

Anemia of prematurity is a common pathology in premature infants. The prevalence of anemia of prematurity is inversely proportional to the gestational age and body weight at birth. The pathogenetic importance of impaired erythropoietin (EPO) production in anemia of prematurity provides the rationale for therapy with erythropoiesis stimulating agents (ESAs) including recombinant EPO. A comparative analysis of the effectiveness of different regimens of recombinant human erythropoietin in extremely and very low birth weight infants (ELBW and VLBW) was studied. Research has been set as a prospective analysis of 133 VLBW and ELBW infants (in the period from December 2017 to February 2019). Gestational age (GA) of the children ranged from 26 to 33 weeks, of these, GA of 75 children (56%) was 30 weeks or less. Depending on the treatment of anemia of prematurity all infants were divided into 5 groups: group 1 (n = 26) – premature babies who were prescribed ESAs since 3 day of life 200 IU/kg 3 times per week subcutaneously; group 2 (n = 21) – premature babies who were prescribed ESAs since 3 day of life 400 IU/kg 3 times per week subcutaneously; group 3 (n = 37) – premature babies who were prescribed ESAs since 8 day of life 200 IU/kg 3 times per week subcutaneously; group 4 (n = 18) – premature babies who were prescribed ESAs since 8 day of life 400 IU/kg 3 times per week subcutaneously; group 5 (n = 31) premature infants who did not receive treatment with recombinant human erythropoietin (control group). Subgroups of children of gestational age ≤ 30 weeks were identified in each group. The groups and subgroups did not differ significantly in gestational age, weight, birth length, and Apgar score at 1 and 5 minutes of life, p &gt; 0.05. Also, there were no statistically significant differences in the age of the 1st transfusion, the frequency and total volume of transfusions, the duration of respiratory therapy, the duration of hospitalization, including treatment in NICU, body weight and age at discharge. The frequency of retinopathy of prematurity stage ≥ 3, periventricular leukomalacia, bronchopulmonary dysplasia of moderate and severe severity, intraventricular hemorrhages of varying severity, necrotizing enterocolitis was not statistically significant in the study groups and subgroups. Statistically significant differences in the concentration of hemoglobin in the peripheral blood of premature infants were revealed at discharge. In the control group, children had a lower level of hemoglobin at discharge (94 g/l) compared with the groups with early appointment of ESAs (109 g/l and 107 g/l in groups 1 and 2, respectively, P0-1 = 0.048 and P0-2 = 0.047) due to newborn GA ≤ 30 weeks. It is preferable to use of the drug ESAs at a dose of 200 IU/kg 3 p/week p/, starting from the 3rd day of life. The effectiveness of erythropoietin therapy, the time of its start and various treatment regimens remain controversial issues that require further study. The study was approved by the Independent Ethics Committee of the National Medical Research Center for Obstetrics, Gynecology and Perinatology named after Academician V.I. Kulakov.

Does a Single Low Dose Preoperative Intravenous Erythropoietin Affect Postoperative Blood Loss and Transfusion in Elderly Hip Fracture Patients Receiving Intravenous Iron Therapy: A Randomized Controlled Trial

Background: Combined recombinant human erythropoietin (rHuEPO) and iron therapy significantly reduced postoperative blood loss (PBL) and allogeneic blood transfusion (ABT) in elderly hip fracture (HF) patients. However, the minimum effective rHuEPO dosage and route had not been studied before.&#x0D; Objective: To evaluate the efficacy of single low dose preoperative intravenous rHuEPO on PBL and ABT in elderly HF.&#x0D; Methods: A randomized controlled trial (RCT) in 32 elderly HF underwent surgical intervention was conducted. The patients were randomly assigned to receive a single dose of 10 000 IU rHuEPO (EPO group, n = 16) or placebo (control group, n = 16) on admission. All patients were given 200-mg iron sucrose intravenously for 3 days after admission. Perioperative data, outcome related to PBL, ABT, rHuEPO adverse effects, and functional outcome during 1-year period were collected and analyzed.&#x0D; Results: There was no significant difference in demographic data, postoperative complication, and functional outcome between both groups (P &lt; .05). Total hemoglobin loss (THL) and the number of patients receiving ABT in EPO group (2.1 ± 1.0 g/dL and 12 patients) did not significant differ from those in control group (2.2 ± 0.8 g/dL and 10 patients) (P = .81 and P = .44, respectively). However, EPO group demonstrated a nonsignificant greater in hemoglobin recovery (P = .07) and increase in reticulocyte count (P = .10).&#x0D; Conclusion: Combined single low dose preoperative intravenous rHuEPO with iron therapy does not significantly reduce PBL and ABT in elderly HF compared to who received intravenous iron therapy alone. However, this adjunct rHuEPO may hasten the hemoglobin recovery and helpful for the patients’ outcome.

A working model for hypothermic neuroprotection.

Therapeutic hypothermia significantly improves survival without disability in near-term and full-term newborns with moderate to severe hypoxic-ischaemic encephalopathy. However, hypothermic neuroprotection is incomplete. The challenge now is to find ways to further improve outcomes. One major limitation to progress is that the specific mechanisms of hypothermia are only partly understood. Evidence supports the concept that therapeutic cooling suppresses multiple extracellular death signals, including intracellular pathways of apoptotic and necrotic cell death and inappropriate microglial activation. Thus, the optimal depth of induced hypothermia is that which effectively suppresses the cell death pathways after hypoxia-ischaemia, but without inhibiting recovery of the cellular environment. Thus mild hypothermia needs to be continued until the cell environment has recovered until it can actively support cell survival. This review highlights that key survival cues likely include the inter-related restoration of neuronal activity and growth factor release. This working model suggests that interventions that target overlapping mechanisms, such as anticonvulsants, are unlikely to materially augment hypothermic neuroprotection. We suggest that further improvements are most likely to be achieved with late interventions that maximise restoration of the normal cell environment after therapeutic hypothermia, such as recombinant human erythropoietin or stem cell therapy.

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.

Pathophysiological aspects of red blood cells in end-stage renal disease patients resistant to recombinant human erythropoietin therapy.

Modified, bioreactive red blood cells (RBCs) and RBC-derived microvesicles (MVs) likely contribute to the hematological and cardiovascular complications in end-stage renal disease (ESRD). This study assesses the physiological profile of RBCs in patients with ESRD receiving standard or high doses of recombinant human erythropoietin (rhEPO). Blood samples from twenty-eight patients under sustained hemodialysis, responsive, or not to standard rhEPO administration were examined for RBC morphology, fragility, hemolysis, redox status, removal signaling, membrane protein composition, and microvesiculation before and after dialysis. Acute effects of uremic plasma on RBC features were examined in vitro through reconstitution experiments. Overall, the ESRD RBCs were characterized by pathological levels of shape distortions, surface removal signaling, and membrane exovesiculation, but reduced fragility compared to healthy RBCs. Irreversible transformation of RBCs was found to be a function of baseline Hb concentration. The more toxic uremic context in non-responsive patients compared to rhEPO responders was blunted in part by the antioxidant, antihemolytic, and anti-apoptotic effects of high rhEPO doses, and probably, of serum uric acid. A selective lower expression of RBC membrane in complement regulators (CD59, clusterin) and of CD47 "marker-of-self" was detected in non-responders and responders, respectively. Evidence for different short-term dialysis effects and probably for a different erythrocyte vesiculation mechanism in rhEPO responsive compared to non-responsive patients was also revealed. Deregulation of RBC homeostasis might involve diverse molecular pathways driving erythrocyte signaling and removal in rhEPO non-responders compared to responsive patients.

Effect of Short-term Erythropoietin Therapy on Insulin Resistance and Serum Levels of Leptin and Neuropeptide Y in Hemodialysis Patients.

Introduction:Insulin resistance (IR) is a known complication of end-stage kidney disease (ESKD). It may be an important therapeutic target in stages of chronic kidney disease.Aim:The study was conducted to evaluate the effect of short-term treatment with recombinant human erythropoietin (rHuEpo) therapy on IR, serum leptin, and neuropeptide Y in ESKD patients on hemodialysis.Materials and Methods:Thirty ESKD patients were enrolled in the study and were randomly assigned into two groups. Erythropoietin (rHuEpo) group consisted of 15 patients (7 females, 8 males, mean age 47.8 ± 9.3 years) treated with rHuEpo therapy after each session of dialysis. No-rHuEpo group consisted of 15 patients (7 females, 8 males, mean age 45.5 ± 8.6 years) not treated with rHuEpo. In addition to, control group consisted of 15 healthy controls (6 females, 9 males, mean age 48.8 ± 11 years).Results:The mean fasting insulin (11 ± 4.2 mU/L) and homeostatic model assessment of IR (HOMA-IR) test (2.6 ± 1.1) were significantly higher in ESKD patients than control group (6.6 ± 1.4 mU/L and 1.5 ± 0.3, respectively). There were significant decreases in glycated hemoglobin (HbA1c) (5.6 ± 1%), fasting insulin level (9.3 ± 3.1 μU/mL), HOMA-IR (2.2 ± 0.7), and serum leptin levels (17.4 ± 8.7 ng/mL) also significant increase in neuropeptide Y levels (113 ± 9.9 pg/mL) after 3 months of rHuEpo therapy, in addition to further significantly decrease fasting insulin levels (7.1 ± 2.1 μU/mL) and HOMA-IR (1.7 ± 6) after 6 months in rHuEpo group. In contrast, there were significantly increases in HbA1c% (5.9 ± 0.5%) and leptin levels (42.3 ± 25.3 ng/mL) in No-rHuEpo group throughout the study.Conclusion:IR and hyperleptinemia are improved by recombinant human erythropoietin therapy.

Hepcidin serum levels and resistance to recombinant human erythropoietin therapy in hemodialysis patients

ObjectiveThe aim of this study was to analyze the factors that are associated with the response to erythropoiesis-stimulating agents (ESAs) and its association with hospitalization and mortality rates; to evaluate the serum hepcidin level and its associations with iron profile, inflammatory markers, ESA responsiveness, and mortality; and to determine independent factors affecting ERI and hepcidin. Materials and methodsTo evaluate a dose-response effect of ESAs we used the erythropoietin resistance index (ERI). Patients were stratified in two groups: nonresponders and responders (ERI>15, n=20, and ERI ≤15U/kg/week/g per 100mL, n=153, respectively). Hematological data, hepcidin levels, iron parameters, inflammatory markers, hospitalization and mortality rates were compared between the groups. Multiple regression analysis was used to determine independent factors affecting ERI and hepcidin. ResultsC-reactive protein (CRP) (β=0.078, P=0.007), albumin (β=−0.436, P=0.004), body mass index (β=−0.374, P<0.001), and hospitalization rate per year (β=3.017, P<0.001) were found to be significant determinants of ERI in maintenance hemodialysis (MHD) patients. Inadequate dialysis was associated with higher ERI. Patients with concomitant oncological diseases had higher ERI (31.2±12.4 vs 9.7±8.1U/kg/week/g per 100mL, P=0.002). The hepcidin level was 158.51±162.57 and 120.65±67.28ng/mL in nonresponders and responders, respectively (P=0.33). Hepcidin correlated directly with ERI, dose of ESAs, ferritin and inversely with Hb, transferrin saturation, and albumin. ERI (β=4.869, P=0.002) and ferritin (β=0.242, P=0.003) were found to be significant determinants of hepcidin in MHD patients. The hospitalization rate per year was 2.35±1.8 and 1.04±1.04 in nonresponders and responders, respectively (P=0.011). The mean length of one hospitalization was 25.12±21.26 and 10.82±17.25 days, respectively (P=0.012). Death occurred in 30% of the patients from the responders’ group and in 50% from the nonresponders’ group (P=0.289). The mean hepcidin concentration of patients who died was 141.9±129.62ng/mL and who survived, 132.98±109.27ng/mL (P=0.797). ConclusionsCRP, albumin, BMI, and hospitalization rate per year were found to be significant determinants of ERI in MHD patients. Inadequate dialysis was associated with higher epoetin requirements. There were no difference in patient mortality by ERI, but a significant difference in hospitalization rates and mean length of one hospitalization was revealed. A significant positive relation between hepcidin and ERI was revealed. ERI and ferritin were found to be significant determinants of hepcidin in MHD patients. Hepcidin was not related to mortality.

Pathological and molecular mechanisms underlying resistance to recombinant human erythropoietin therapy in the remnant kidney rat model of chronic kidney disease associated anemia.

Anemia of chronic kidney disease (CKD) can be corrected by treatment with recombinant human erythropoietin (rHuEPO); however, some patients become hyporesponsive. The molecular mechanisms underlying this resistance remain to be elucidated. Our aim was to study hyporesponsiveness to rHuEPO therapy using the remnant kidney rat model of anemia associated with CKD induced by 5/6 nephrectomy. At starting, male Wistar rats were divided in 3 groups, for a 3-week protocol: Sham, CRF (vehicle) and two rHuEPO (200k/kg body weight [BW]/week) treated groups; at the end of protocol, the rHuEPO treated rats were subdivided in responders (CRF200) and non-responders (CRF200NR), according to their hematologic response; blood, cellular and tissue studies were performed. The CRF200 group achieved correction of anemia, while the CRF200NR group developed anemia, after an initial response (1st week) to rHuEPO therapy. CRF and CRF200NR groups presented a trend to higher serum CRP levels; CRF200NR showed also high levels of renal inflammatory markers, such as interleukin (IL)-6, IL-1β, nuclear factor kappa B, connective tissue growth factor (CTGF) and transforming growth factor beta 1 (TGF-β1); no changes were found in iron metabolism. Our data suggest that the development of anemia/rHuEPO hyporesponsiveness is associated with a higher systemic and renal inflammatory condition, favoring hypoxia and triggering an increase in renal expression of HIF-1α, TGF-β1 and CTGF that will further aggravate renal fibrosis, which will enhance the inflammatory response, creating a cycle that promotes disease progression. New therapeutic strategies to reduce inflammation in CKD patients could improve the response to rHuEPO therapy and reduce hyporesponsiveness.

Oxidative stress during erythropoietin hyporesponsiveness anemia at end stage renal disease: Molecular and biochemical studies

Inflammation and oxidative stress are two faces of one coin in end stage renal disease patients (ESRD) on maintenance hemodialysis. Their interconnection induces anemia complicated with erythropoietin hyporesponsiveness. The biochemical bases behind the resistance to erythropoietin therapy with frequent hemoglobinemia, oxidative stress and iron status have not been fully understood. Here two equal groups (40 patients each) of responders and non-responders to recombinant human erythropoietin therapy (higher than 300IU/kg/wk of epoetin) were investigated. Hematological and biochemical analyses of collected blood and serum samples were performed along with serum electrophoretic protein footprinting. The leukocytic DNA fragmentation was used to evaluate the degree of oxidative insult. The good responders showed lower erythrocyte malondialdehyde (E-MDA) level and less DNA fragmentation of circulating leukocytes than poor responders with elevated hemoglobin, albumin, A/G ratio, total iron, and ferritin levels. Contrariwise, lower erythrocyte superoxide dismutase (E-SOD) and catalase activities in EPO poor responder group were noticed. Neither other serum constituents nor electrophoretic protein pattern showed any difference between the two groups. There were higher levels of inflammatory markers, interleukin-6 (IL6) and C-reactive protein (CRP) in EPO poor responder than good responder. The negative correlations between Hb and both IL6 and CRP levels in the present data remotely indicate a positive correlation between inflammatory markers and severity of anemia. A direct correlation between Hb and antioxidant enzymes (E-SOD and catalase) was noticed, while inverse correlation with E-MDA was recorded. The study proved that oral supplementation of vitamin C to ESRD patients might mitigate the previously elevated serum MDA level in these patients.

Renal risk-benefit determinants of recombinant human erythropoietin therapy in the remnant kidney rat model - hypertension, anaemia, inflammation and drug dose.

Clinical studies showed that high doses of recombinant human erythropoietin (rHuEPO) used to correct anaemia in chronic kidney disease (CKD) hyporesponsive patients may lead to deleterious effects. The aim of this study was to analyze the effects of rHuEPO in doses usually used to correct CKD-anaemia (100, 200IU/kg body weight (BW) per week) and in higher doses used in the treatment of hyporesponsive patients (400, 600IU/kg BW per week), focusing on renal damage, hypoxia, inflammation and fibrosis. Male Wistar rats with chronic renal failure (CRF) induced by 5/6 nephrectomy were treated with rHuEPO or with vehicle, over a 3-week period. Haematological, biochemical and renal function analyses were performed. Kidney and liver mRNA levels were evaluated by quantitative real-time polymerase chain reaction (qPCR) and protein expression by Western blot and immunohistochemistry. Kidney histopathological evaluations were also performed. The CRF group developed anaemia, hypertension and a high score of renal histopathologic lesions. Correction of anaemia was achieved with all rHuEPO doses, with improvement in hypertension, renal function and renal lesions. In addition, the higher rHuEPO doses also improved inflammation. Blood pressure was reduced in all rHuEPO-treated groups, compared to the CRF group, but increased in a dose-dependent manner. The current study showed that rHuEPO treatment corrected anaemia and improved urinary albumin excretion, particularly at lower doses. In addition, it is suggested that a short-term treatment with high doses, used to overcome an episode of hyporesponsiveness to rHuEPO therapy, can present benefits by reducing inflammation, without worsening of renal lesions; however, the pro-hypertensive effect should be considered, and carefully managed to avoid a negative cardiorenal impact.

Recombinant Human Erythropoietin Therapy for a Jehovah's Witness Child With Severe Anemia due to Hemolytic-Uremic Syndrome.

Patients with hemolytic-uremic syndrome (HUS) can rapidly develop profound anemia as the disease progresses, as a consequence of red blood cell (RBC) hemolysis and inadequate erythropoietin synthesis. Therefore, RBC transfusion should be considered in HUS patients with severe anemia to avoid cardiac or pulmonary complications. Most patients who are Jehovah's Witnesses refuse blood transfusion, even in the face of life-threatening medical conditions due to their religious convictions. These patients require management alternatives to blood transfusions. Erythropoietin is a glycopeptide that enhances endogenous erythropoiesis in the bone marrow. With the availability of recombinant human erythropoietin (rHuEPO), several authors have reported its successful use in patients refusing blood transfusion. However, the optimal dose and duration of treatment with rHuEPO are not established. We report a case of a 2-year-old boy with diarrhea-associated HUS whose family members are Jehovah's Witnesses. He had severe anemia with acute kidney injury. His lowest hemoglobin level was 3.6 g/dL, but his parents refused treatment with packed RBC transfusion due to their religious beliefs. Therefore, we treated him with high-dose rHuEPO (300 IU/kg/day) as well as folic acid, vitamin B12, and intravenous iron. The hemoglobin level increased steadily to 7.4 g/dL after 10 days of treatment and his renal function improved without any complications. To our knowledge, this is the first case of successful rHuEPO treatment in a Jehovah's Witness child with severe anemia due to HUS.

Resistance to Recombinant Human Erythropoietin Therapy in a Rat Model of Chronic Kidney Disease Associated Anemia.

This study aimed to elucidate the mechanisms explaining the persistence of anemia and resistance to recombinant human erythropoietin (rHuEPO) therapy in a rat model of chronic kidney disease (CKD)-associated anemia with formation of anti-rHuEPO antibodies. The remnant kidney rat model of CKD induced by 5/6 nephrectomy was used to test a long-term (nine weeks) high dose of rHuEPO (200 UI/kg bw/week) treatment. Hematological and biochemical parameters were evaluated as well as serum and tissue (kidney, liver and/or duodenum) protein and/or gene expression of mediators of erythropoiesis, iron metabolism and tissue hypoxia, inflammation, and fibrosis. Long-term treatment with a high rHuEPO dose is associated with development of resistance to therapy as a result of antibodies formation. In this condition, serum EPO levels are not deficient and iron availability is recovered by increased duodenal absorption. However, erythropoiesis is not stimulated, and the resistance to endogenous EPO effect and to rHuEPO therapy results from the development of a hypoxic, inflammatory and fibrotic milieu in the kidney tissue. This study provides new insights that could be important to ameliorate the current therapeutic strategies used to treat patients with CKD-associated anemia, in particular those that become resistant to rHuEPO therapy.

Recombinant human erythropoietin (rHuEPO) reduces transfusion requirements in anaemia of prematurity

Background: During the last two decades with the application of advanced technological supports have improved the survival rate of preterm very low birth weight (PT VLBW) infants. At the same time anemia of prematurity (AOP) one of the most frequent complications of these patients also has been increased in the neonatal units. Packed red blood cell (PRBC) transfusions are the mainstay of treatment of AOP. The frequency of blood transfusion is directly related to the exposure of the tiny preterm infants to various risks of transfusion.Objectives : To evaluate whether recombinant human erythropoietin (rHuEPO) therapy reduces the need of transfusions in AOP.Methods : A randomized controlled trial study was carried out at Neonatal Unit and Intensive Care Unit (ICU) of Dhaka Shishu (children) Hospital, Dhaka, Bangladesh with 60 PTVLBW neonates. Among them 30 in group I (rHuEPO group) and 30 in group II (control) were assigned. Therapy with rHuEPO (200 IU / kg / dose) thrice weekly was initiated on day 7 of life to group I for 2 weeks. From day 14 or after that as soon as enteral feeding was initiated oral iron and folic acid were received by both groups. Hematological assessment (haemoglobin, haematocrit level and reticulocyte count) were done at 6 and 10 weeks of life.Results : At the time of enrollment in the study PTLBW babies of both groups were almost similar in gestetional age, birth weight, hemoglobin, hematocrit values and reticulocyte count (p&gt;0.05). During the 10 weeks observation period, hematological values were increased and the number of blood transfusions as well as the number of infants who received any transfusion were reduced in rHuEPO group compared to control group (p&lt;0.01). No adverse effect of erythropoietin were found.Conclusion : The combination of rHuEPO and Iron, folic acid therapy significantly reduces the number of blood transfusion as well as the percentage of infants who received any transfusion in AOP.Northern International Medical College Journal Vol.6(2) 2015: 53-56