EPO Dose Research Articles

Characterization of DNA concentration in urine and dried blood samples to detect the c.577 deletion within the EPO gene.

The EPO gene variant, c.577del (VAR-EPO), was discovered in the Chinese population in 2021. The mutated protein is naturally present in urine from individuals heterozygous for the variant. Electrophoresis methods currently applied in anti-doping laboratories produce a pattern in samples from individuals carrying VAR-EPO that cannot be unambiguously distinguished from individuals who received recombinant EPO doses. Consequently, the analysis of blood samples is obligatory to facilitate interpretation of suspicious findings from urine samples. However, this complicates the process and delays the reporting. Objective of this study was to develop EPO c.577del detection in urine and dried blood samples (DBS) in order to facilitate and accelerate EPO results management. Moreover, estimation of the success rate of sequencing regarding concentration of DNA in urine and DBS was evaluated. Conclusive results regarding Sanger sequencing were obtained for all samples with DNA concentrations above 0.024 ng/μL DNA in 80% of urines samples from volunteers. The potential success of DNA sequencing rate in athletes' urines was investigated. A total of 191 urine samples were considered. DNA concentration exceeding 0.024 ng/μL was detected in 85% of the samples. Interestingly, in-competition samples had a significantly higher DNA concentration than out-of-competition male urine samples (0.330 vs. 0.084 ng/μL). Moreover, conclusive EPO sequences were obtained for 100% of DBS (cellulose and polymer matrices). In conclusion, method for detection of EPO gene variant was developed in urine and DBS. Characterization of DNA concentration was performed in order to evaluate the probability of success of sequencing EPO gene in anti-doping field.

PB2045: POLYCYTHEMIA VERA IN YOUNG SUBJECTS: ABOUT A COHORT OF 11 CASES

Background: Polycythemia Vera (PV) is a typical Philadelphia-negative (Ph_) myeloproliferative disease. It is secondary in 95% of cases to the JAK 2 mutation on exon 14. The median age at diagnosis is 65 years. PV is unusual in young patients, so that little information is available on long-term clinical evolution in this particular group. Aims: The aim of this study is to describe the clinical presentation, biologic features, treatment approaches, and long-term outcome especially the risk of thrombosis. Methods: Of all the 64 patients followed in our department for PV, we report 11 cases aged less than 55 years. The inclusion criteria were a diagnosis satisfying the PVSG criteria and, from 2016 on, the WHO criteria. Secondary causes of erythrocytosis were carefully ruled out in all patients. At diagnosis, cytogenetic and molecular analysis were not done in our patients. Search for JAK2 mutation and serum EPO dosage were performed in all cases. Results: PV in young patients represents 17% of all PV followed. Median age of our population is 44 years, range 32-52, with 27% of patients under 40 years old. slightly more often in men with (sex ratio 1.75). Arterial hypertension is the most common comorbidity and it is a cardiovascular risk factor in the majority of patients. A thromboembolic event revealing PV is found in 2 patients. The main clinical signs were significant burning sensation in fingers and palms due to the increased blood viscosity, splenomegaly which observed in 63% of patients, and the occurrence of severe itching on contact with warm bath. Thromboembolic events occurred in 3 patients during the evolution. All patients had the diagnosis of absolute erythrocytosis with moderate hyperleukocytosis and thrombocytosis. Bone marrow biopsy showed hypercellular bone marrow with erythroid and megakaryocytic lineage hyperplasia. The JAK2 V617F mutation was positive with an average allelic load high at 63.1% [22.9 - 93.6]. The dosage of serum EPO was low with an average of 1 mU/ML. During the follow-up period, no patient had progression into acute leukemia or myelofibrosis with myeloid metaplasia, thus no death. The median survival is 49 months [3-99] and the survival without thromboembolic event is 42 months [3-99]. The majority of patients were treated by phlebotomy with 1 or 2 units per month, before starting hydroxy urea. The use of the latter in association with Aspirin (n=10 pts) reduced the use of bloodletting. The thrombotic events required treatment with antithrombotic drug. No patient was treated with Ruxolitinib (treatment not available). Summary/Conclusion: PV remains rare in patients under 55 years of age (17% in our cohort). This has an impact on overall survival and thromboembolic event-free survival with a good prognosis in the young population.

Enhancing Erythropoiesis by a Phytoestrogen Diarylheptanoid from Curcuma comosa.

Erythropoietin (Epo) is widely used for the treatment of anemia; however, non-hematopoietic effects and cancer risk limit its clinical applications. Therefore, alternative molecules to improve erythropoiesis in anemia patients are urgently needed. Here, we investigated the potential effects of a phytoestrogen diarylheptanoid (3R)-1,7-diphenyl-(4E,6E)-4,6-heptadien-3-ol, (ASPP 049) isolated from Curcuma comosa on promoting erythropoiesis. Treatment with C. comosa extract improved anemia symptoms demonstrated by increasing red blood cell numbers, hematocrit, and hemoglobin content in anemic mice. In addition, ASPP 049, the major compound isolated from C. comosa, enhanced the suboptimal Epo dosages to improve erythroid cell differentiation from hematopoietic stem cells, which was inhibited by the estrogen receptor (ER) antagonist, ICI 182,780. Moreover, the ASPP 049-activated Epo-Epo receptor (EpoR) complex subsequently induced phosphorylation of EpoR-mediated erythropoiesis pathways: STAT5, MAPK/ERK, and PI3K/AKT in Epo-sensitive UT-7 cells. Taken together, these results suggest that C. comosa extract and ASPP 049 increased erythropoiesis through ER- and EpoR-mediated signaling cascades. Our findings provide insight into the specific interaction between a phytoestrogen diarylheptanoid and Epo-EpoR in a hematopoietic system for the potential treatment of anemia.

A multicenter study of the clinical, laboratory characteristics, and potential prognostic factors in patients with amyloid A amyloidosis on hemodialysis.

While light chain (AL) amyloidosis is more common in western countries, the most common type of amyloidosis is amyloid A (AA) amyloidosis in Eastern Mediterranean Region, including Turkey. Although worse prognosis has been attributed to the AL amyloidosis, AA amyloidosis can be related to higher mortality under renal replacement therapies. However, there are no sufficient data regarding etiology, clinical presentation, and prognostic factors of AA amyloidosis. The objective of our study is to evaluate the clinical, laboratory characteristics, and possible predictive factors related to mortality in patients with AA amyloidosis undergoing hemodialysis (HD). This multicenter, cross-sectional study was a retrospective analysis of 2100 patients on HD. It was carried out in 14 selected HD centers throughout Turkey. Thirty-two patients with biopsy-proven AA amyloidosis and thirty-two control patients without AA amyloidosis undergoing HD were included between October 2018 and October 2019. There was no significant difference between the groups in terms of age and dialysis vintage. Causes of AA amyloidosis, treatment (colchicine and/or anti-interleukin 1 [IL] treatment), and the number of familial Mediterranean fever (FMF) attacks in the last year in case of FMF, systolic and diastolic blood pressures, biochemical values such as mean CRP, hemoglobin, serum albumin, phosphorus, calcium, PTH, ferritin, transferrin saturation, total cholesterol levels, EPO dose, erythropoietin-stimulating agents resistance index, interdialytic fluid intake, body mass indexes, heparin dosage, UF volume, and Kt/V data in the last year were collected by retrospective review of medical records. Prevalence of AA amyloidosis was found to be 1.87% in HD centers. In amyloidosis and control groups, 56% and 53% were male, mean age was 54 ± 11 and 53 ± 11 years, and mean dialysis vintage was 104 ± 94 and 107 ± 95 months, respectively. FMF was the most common cause of AA amyloidosis (59.5%). All FMF patients received colchicine and the mean colchicine dose was 0.70 ± 0.30 mg/day. 26.3% of FMF patients were unresponsive to colchicine and anti-IL-1 treatment was used in these patients. In AA amyloid and control groups, erythropoietin-stimulating agents resistance index were 7.88 ± 3.78 and 5.41 ± 3.06 IU/kg/week/g/dl, respectively (p=0.008). Additionally, higher CRP values (18.78 ± 18.74 and 10.61 ± 10.47 mg/L, p=0.037), lower phosphorus (4.68 ± 0.73 vs. 5.25 ± 1.04 mg/dl, p=0.014), total cholesterol (135 ± 42 vs. 174 ± 39 mg/dl, p < 0.01), and serum albumin (3.67 ± 0.49 mg/dl, 4.03 ± 0.22, p < 0.01) were observed in patients with AA amyloidosis compared to the control group. In this study, we found that long-term prognostic factors including higher inflammation, malnutritional parameters, and higher erythropoietin-stimulating agents resistance index were more frequent in AA amyloidosis patients under HD treatment.

Erythropoietin and derivatives: Potential beneficial effects on the brain.

Erythropoietin (Epo), the main erythropoiesis-stimulating factor widely prescribed to overcome anemia, is also known nowadays for its cytoprotective action on non-hematopoietic tissues. In this context, Epo showed not only its ability to cross the blood-brain barrier, but also its expression in the brain of mammals. In clinical trials, recombinant Epo treatment has been shown to stimulate neurogenesis; improve cognition; and activate antiapoptotic, antioxidant, and anti-inflammatory signaling pathways. These mechanisms, proposed to characterize a neuroprotective property, opened new perspectives on the Epo pharmacological potencies. However, many questions arise about a possible physiological role of Epo in the central nervous system (CNS) and the factors or environmental conditions that induce its expression. Although Epo may be considered a strong candidate to be used against neuronal damage, long-term treatments, particularly when high Epo doses are needed, may induce thromboembolic complications associated with increases in hematocrit and blood viscosity. To avoid these adverse effects, different Epo analogs without erythropoietic activity but maintaining neuroprotection ability are currently being investigated. Carbamylated erythropoietin, as well as alternative molecules like Epo fusion proteins and partial peptides of Epo, seems to match this profile. This review will focus on the discussion of experimental evidence reported in recent years linking erythropoietin and CNS function through investigations aimed at finding benefits in the treatment of neurodegenerative diseases. In addition, it will review the proposed mechanisms for novel derivatives which may clarify and, eventually, improve the neuroprotective action of Epo.

Selective Proliferation of Gene-Modified Human Erythroid Cells with Truncated Erythropoietin Receptors

Hematopoietic stem cell gene therapy for hemoglobin disorders, such as sickle cell disease, has stringent requirements for high-level gene marking with robust β-globin expression in erythroid cells for widespread successful clinical application. In vivo selection of gene-modified cells could allow for enhanced therapeutic effects. Erythropoietin (Epo) is a key cytokine for erythroid cell proliferation and differentiation. Various mutations in a C-terminal negative regulatory region of Epo receptor (EpoR) were reported in familial polycythemia. We hypothesized that coexpression of EpoR activated by C-terminal deletions could confer a selective advantage among gene-modified erythroid cells, thus raising the curative potential of therapeutic globin vectors.We generated a selectable truncated human EpoR (thEpoR) by deleting a 40 amino acid C-terminus, and prepared lentiviral vectors encoding both thEpoR and GFP (thEpoR/GFP) connected by internal ribosome entry site (IRES) controlled by murine stem cell virus promoter (Mp). K562 cells, Epo-dependent immortalized erythrocyte HUDEP-2 cells, and human CD34+ cell-derived erythroid cells (Epo-based differentiation) were transduced with thEpoR/GFP vector, and GFP-positive percentages (%GFP) were evaluated for 1-2 weeks. We observed increasing %GFP over 1 week for thEpoR/GFP-transduced HUDEP-2 cells at various Epo doses (3, 1, 0.3, and 0.1U/ml, p<0.01 in all doses) but not in the GFP only control (Figure). Additionally, there was no increase of %GFP for both thEpoR/GFP and GFP only vectors in Epo-independent K562 cells. Two weeks after erythroid differentiation of transduced CD34+ cells (2U/ml Epo), we observed higher glycophorin A-positive erythroid cell percentages (%GPA; 81±0 vs 50±3%, p<0.01), higher GFP and GPA-double positive percentages (%GFP+GPA+; 63±0 vs 44±3%, p<0.01), and larger cell expansion (2.8±0.6 vs 1.6±1.0 fold, p<0.01) in thEpoR/GFP transduction, as compared to GFP only control. These data demonstrate that thEpoR enhances erythroid cell expansion under Epo exposure in human erythroid cells. Accelerated erythroid differentiation can be induced by thEpoR in human CD34+ cells.Since Epo-based negative feedback among erythroid cells is required to maintain normal hematopoiesis, we switched from the constitutive Mp to the erythroid specific Ankyrin-1 (ANKp) or EpoR promoter with or without a WPRE enhancer. After erythroid differentiation of transduced CD34+ cells with the erythroid specific thEpoR/GFP vectors, we observed higher %GPA (81-85% vs 69±4%, p<0.01) in all thEpoR/GFP vectors, and higher %GFP+GPA+ (32±3 and 45±0 vs 22±1%, p<0.01) in thEpoR/GFP vectors with Mp and ANKp-WPRE, as compared to GFP only (Mp). Interestingly, higher γ-globin production in thEpoR/GFP transduction (12±0 vs 8±0%, p<0.01) was detected by HPLC, as compared to GFP only and no transduction controls. These data demonstrate that a thEpoR-based selective advantage in human erythroid cells can be controlled by erythroid specific promoters, and possibly induce γ-globin production.We then evaluated the ANKp-WPRE-derived thEpoR/GFP utilizing either an IRES or a 2A sequence to coexpress a GFP reporter (thEpoR-IRES-GFP, thEpoR-2A-GFP, and GFP-2A-thEpoR), since lower GFP intensity was observed in all thEpoR-IRES-GFP vectors (17-24 vs 95±5, p<0.01) than GFP only vector (Mp). In transduced CD34+ cell-derived erythroid cells, we observed higher %GFP+GPA+ in the GFP-2A-thEpoR vector (50±2 vs 37±3%, p<0.01), and greater cell expansion in thEpoR-IRES-GFP and GFP-2A-thEpoR vectors (100±7 and 88±6 vs 62±5 fold, p<0.05), as compared to GFP only vector with ANKp-WPRE. Lower GFP intensity was observed in all thEpoR/GFP vectors (14-34 vs 106±5, p<0.01) than the GFP only control, while the highest GFP intensity was obtained in GFP-2A-thEpoR (34±0). These data suggest that ANKp-WPRE with GFP-2A-thEpoR is optimal for erythroid specific expression, which should allow for both selection and detection of GFP signals in gene-modified erythroid cells in vitro and in vivo animal models.In summary, we developed erythroid specific thEpoR-expressing vectors, allowing for larger expansion and accelerated differentiation in human erythroid cells. While farther in vivo studies are desirable, this system should be beneficial for providing a selective advantage for gene-modified erythroid cells in gene therapy strategies for hemoglobin disorders. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

MO799IS COMBINATION OF MAINTENANCE HEMODIALYSIS WITH HEMOPERFUSION AN EFFECTIVE METHOD IN MANAGEMENT OF RENAL OSTEODYSTROPHY AND INFLAMMATION IN HEMODIALYSIS PATIENTS?

Abstract Background and Aims Some of the conditions which occur in maintenance hemodialysis (MHD) patients with a high incidence resulting in a decline in their quality of life, include malnutrition, renal osteodystrophy, refractory hypertension and chronic systemic inflammation. In developing countries, due to the low level of economic development, low-flux dialysis is the main means of extracorporeal blood purification therapy. But it can hardly remove the middle and large molecule uremic toxins and protein-bound toxins; as a result, the patients suffer from long-term complications and poor quality of life. In this study, we attempted to investigate whether the combination of maintenance hemodialysis (MHD) with hemoperfusion (HP) could improve the clearance rate of middle and large molecule uremic toxins so as to improve their uremic complications. Method A total of 54 patients, who underwent routine hemodialysis, were assessed in this study. Those patients were randomly divided into two groups: Group 1 (27 patients) received combined treatment of HD with hemoperfusion (HP) in this regimen: HD 2 times a week with HD+HP once a week two times in a row, then after two weeks, and afterwards once a month as a maintenance treatment. Group 2 (27 patients) was only undergoing maintenance HD 3 times a week. The clinical and laboratory properties of both groups were followed up for 18 months, whereas the primary outcomes included normal clinical data, high sensitive C-reactive protein (hsCRP), immunoreactive parathyroid hormone (iPTH), phosphorus (P04), calcium (Ca), albumin, iron (Fe), total iron binding capacity (TIBC), hemoglobin, Epo doses and types of hypertensive drugs. Results At the end of the 18-month observation, the serum concentration of albumin, P04, hsCRP, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were lower with Group 1 than with Group 2 (p&amp;lt;0.05). Whereas, higher levels of iPTH were noticed in group 1, but when the laboratory and clinical data are analysed of the group 1 alone a statistically significant lower values after the observational period are noticed especially in the serum values of iPTH (p&amp;lt;0.05), P04 (p&amp;lt;0.001), CRP (p&amp;lt;0.011), SBP and DBP (p&amp;lt;0.05). Conclusion HD+HP was superior to HD in regularly eliminating middle and large molecule uremic toxins accumulated in the body which is mostly shown through reducing the values of iPTH and hsCRP. These findings suggest a potential role for HD+HP in the treatment of inflammation and renal osteodystrophy as well, because lowering these values of iPTH leads to a normalization of other minerals which is expected and therefore leads to a stabilization of this long-term uremic complications, which can improve the overall general condition of the MHD patient.

Plasma Hepcidin Level in Hemodialysis Patients and its Relationship to Anemia Therapy and Dialysis Efficiency

Background: Hepcidin is a small peptide produced mainly by hepatocytes, macrophages and other cells. In addition to its antimicrobial effects, it is the primary regulator of iron metabolism as it controls both dietary iron absorption from the duodenum and the release of that iron by reticuloendothelial cells. Objective: Study of plasma hepcidin level and its relationship to the parameters of iron status, anemia therapy, and parameters of dialysis efficiency in hemodialysis patient. Patients and Methods: 106 subjects were enrolled in our study. They were divided into two groups: Group 1 (control group) included10 healthy subjects. Group 2 included96 end-stage renal disease (ESRD) patients on regular hemodialysis; they were subdivided into two groups according to the median plasma hepcidin level. full history, physical examination and detailed analysis of medical records to elucidate the cause of renal failure if present and duration of hemodialysis, estimation of glomerular filtration rate (eGFR) and calculating Kt/V. Laboratory investigations includingCBC, liver function tests, kidney function tests, serum iron, serum ferritin, total iron binding capacity (TIBC), transferrin saturation and plasma hepcidin level were measured. In addition to Pelvi-abdominal ultrasound was done. Results: Plasma hepcidin levels were higher in maintenance hemodialysis patients than in healthy control subjects. Also, there was a significant and independent positive correlation between hepcidin and both serum ferritin levels and KT/V. While there was significant negative correlation between serum hepcidin levels & EPO dose. Conclusion: High plasma hepcidin levels in HD patients depending on the magnitude of the inflammatory process and on rhEPO doses. Close interaction between hematological indices, iron status and plasma hepcidin levels.

Repetitive Erythropoietin Treatment Improves Long-Term Neurocognitive Outcome by Attenuating Hyperoxia-Induced Hypomyelination in the Developing Brain.

Introduction: Preterm infants born before 28 weeks of gestation are at high risk of neurodevelopmental impairment in later life. Cerebral white and gray matter injury is associated with adverse outcomes. High oxygen levels, often unavoidable in neonatal intensive care, have been identified as one of the main contributing factors to preterm brain injury. Thus, preventive and therapeutic strategies against hyperoxia-induced brain injury are needed. Erythropoietin (Epo) is a promising and also neuroprotective candidate due to its clinical use in infants as erythropoiesis-stimulating agent.Objective: The objective of this study was to investigate the effects of repetitive Epo treatment on the cerebral white matter and long-term motor-cognitive outcome in a neonatal rodent model of hyperoxia-induced brain injury.Methods: Three-day old Wistar rats were exposed to hyperoxia (48 h, 80% oxygen). Four doses of Epo (5,000 IU/kg body weight per day) were applied intraperitoneally from P3-P6 with the first dose at the onset of hyperoxia. Oligodendrocyte maturation and myelination were evaluated via immunohistochemistry and Western blot on P11. Motor-cognitive deficits were assessed in a battery of complex behavior tests (Open Field, Novel Object Recognition, Barnes maze) in adolescent and fully adult animals. Following behavior tests animals underwent post-mortem diffusion tensor imaging to investigate long-lasting microstructural alterations of the white matter.Results: Repetitive treatment with Epo significantly improved myelination deficits following neonatal hyperoxia at P11. Behavioral testing revealed attenuated hyperoxia-induced cognitive deficits in Epo-treated adolescent and adult rats.Conclusion: A multiple Epo dosage regimen protects the developing brain against hyperoxia-induced brain injury by improving myelination and long-term cognitive outcome. Though current clinical studies on short-term outcome of Epo-treated prematurely born children contradict our findings, long-term effects up to adulthood are still lacking. Our data support the essential need for long-term follow-up of preterm infants in current clinical trials.

Conversion of haemodialysis patients from iron sucrose to iron isomaltoside: a real-world experience

BackgroundAnaemia is common in haemodialysis (HD) patients and associated with significant morbidity and mortality. Intravenous (IV) iron combined with erythropoiesis-stimulating agents (ESA) is the mainstay treatment of anaemia in these patients. The comparative efficacy and risk of adverse events with IV iron preparations have been assessed in only a few trials.MethodsThis was a retrospective observational study in 2 centres designed to compare the safety and efficacy of iron sucrose (IS-Venofer®) versus iron isomaltoside (IIM-Diafer®) in haemodialysis patients. The study included patients currently on dialysis and receiving Venofer who were switched to Diafer® and monitored for at least 12 months for each iron preparation.ResultsA total of 190 patients were included and had a mean age of 65.8 years (SD ± 15.5). Non-inferiority was confirmed with no change in mean haemoglobin per mg of iron administered over a 12-month period.In total there were 41,295 prescriptions of iron isomaltoside and 14,685 of iron sucrose with no difference in the number of reported adverse events during the study period (7 each, none were severe).There was a statistically significant effect on Hb over time after conversion, including adjustment for multiple comparisons. There were significant improvements in ferritin over time, which remained at 6 months (P < 0.01). The weekly iron dose was similar after adjustment (P = 0.02). The EPO dose did not differ significantly after month 0 in patients switched to IIM.ConclusionsThis study demonstrates the comparative safety and efficacy of iron isomaltoside versus iron sucrose, with similar dosing schedules in dialysis patients. Iron isomaltoside is non-inferior to iron sucrose in maintaining Hb in patients on regular haemodialysis/haemodiafiltration with no difference in the number of reported adverse events.

P1112COMPARISON OF EFFICACY BETWEEN MAINTENANCE HEMODIALYSIS AND THEIR COMBINATION WITH HEMOPERFUSION IN PATIENTS UNDERGOING CHRONIC HEMODIALYSIS TREATMENT

Abstract Background and Aims The occurance of mid- and longterm uremic complications is related to the low clearance rate of middle and large molecule uremic toxins when hemodialysis (HD) alone is adopted. As the uremic toxins and their corresponding biological effects become increasingly clear, blood purification treatment that aims to remove these toxins, has developed from a stage of life-sustaining to improving the quality of life. The objective of this study was to evaluated demographic, clinical and laboratory data in patients who underwent the combination of maintenance hemodialysis with hemoperfusion (HP) and in those who recieved HD alone and to investigate whether this combination could improve the clearance rate of middle and large molecule uremic toxins. Method A total of 26 patients, who underwent routine hemodialysis, were assessed in this study. Those patients were randomly divided into three groups: Group 1 (7 patients) received combined treatment of HD with HP biweekly (HD 2 times a week with HD+HP once a week), whereas Group 2 (10 patients) was given HD with high flux dialyzer and Group 3 (9 patients) was given HD with low flux dialyzer 3 times a week. This study was followed for 4 months. Before and after the observational period demographic and clinical data were taken from the medical history and blood samples were taken for hemoglobin (Hb), iron (Fe), total iron binding capacity (TIBC), albumin (Alb), calcium (Ca), phosphorus (P04) and parathyroid hormone (PTH). Results This study included 13 female and 13 male patients with a mean age of 41, 62 + 11.12 and a mean dialysis duration of 62, 78+53, 33 months. When it comes to baseline characteristics, patients of the group 3 were significantly older than patients in other groups (p=0.001). At the end of the four months observation period, the same difference according to age was noticed (p=0.01). Also, HD+HP group had significantly higher values of TIBC (p=0.006) and significantly lower serum levels of P04 (p=0.001). EPO doses were very similar in group 1 and 2, but in group 3 there were noticeably lower than in those two groups but without a significant difference. The serum levels of albumin were higher in group 3 compared to the other two groups but also without statistical difference. No statistical difference between groups after the follow up period was observed in terms of Hb, Fe, PTH, Ca, BMI, duration of dialysis treatment and vascular access. When groups are viewed individually, in the HD+HP group serum P04 levels were significantly lower after the 4 months off the follow up period than it was at the beginning (p=0.031) and also TIBC was significantly higher (p=0.018). In group 2 the values of TIBC were significantly lower after the follow up period than it was at the beginning (p=0.025). No significant difference was noticed in group 3 but serum PTH levels tends to decrease after 4 months compared to baseline measurement. Conclusion This combination treatment of HD with HP was superior to HD in reducing levels of phosphorus. These findings suggests a potential role of reducing the risk of cardiovascular events in this population especially when it is known that hyperphosphatemia has been pointed out as the primary culprit in the process of cardiovascular calcification. Also, patients who underwent the combined treatment showed higher values of TIBC but unfortunately no difference was noticed between Hb levels and EPO doses. These results eventually demonstrates their role in the improvement of renal disease anemia, which opens up the possibility of further research on a larger sample and over a longer period of time.

P0303IS THERE ANY UTILITY OF USING A RATIO BETWEEN SERUM BIOMARKERS AND PREDIALYSIS SERUM CREATININE IN ESKD PATIENTS TREATED WITH HEMODIALYSIS?

Abstract Background and Aims Serum creatinine is mainly used to estimate GFR in a patient with steady state kidney function. In ESKD patients on HD therapy however it may be used as a surrogate muscle mass indicator The predialysis serum creatinine decreases in time with HD therapy duration and low pre dialysis concentrations have been associated with increased all cause and cardiovascular mortality probably related to protein energy wasting. Under these conditions our working hypothesis was that exploring blood cytokine biomarkers (BM) and their significance in HD patients the correction of BM blood values to a prognosis marker (as pre dialysis serum creatinine) may change the results of our findings. Method 63 G5D patients (21 female and 42 male median age 61years.) have been included in a prospective study concerning assessment of 5 blood cytokine biomarkers (KIM-1,TGF beta, IL-6, soluble Klotho and VEGF) and their prognosis significance. At inclusion, the median duration of HD therapy was 3.2 years. Patients have been assessed for cardiovascular disease (including history, EKG and cardiac ultrasound, PVW). Standard blood biochemistry and blood count have been performed. Enzyme- linked immunosorbent assays were used for the assessment of blood BM. Statistical correlations of cytokine values and cytokine/predialysis serum creatinine with the collected data were performed Results The average plasma levels of the investigated biomarkers were: KIM-1 267.1+/-482.9 pg/ml, IL-6 7.3+/-5.1 pg/ml, TGFβ 298.9+/-609.5 pg/ml, VEGF 1371.3+/-787.5 pg/ml, Soluble Klotho 305.7+/-341.6 pg/ml. The average predialysis serum creatinine (SCr) was 8.4+/-1.9 mg/dl. KIM-1 levels correlated with CRP (r=0.28, p=0.028) and Left Ventricular Hypertrophy (LVH) (r= - 0.28, p=0.026). The correlations of KIM-1/SCr did not significantly differ (with CRP r= 0.29, p=0.023 and LVH r= - 0.25, p= 0.047). IL-6 levels correlated with sKlotho (r=0.37, p=0.003), IL-6/SCr however correlated with iPTH (r=0.26, p=0.045), sKlotho (r=0.90, p=0.001), Alc.P (r=0.32, p=0.012), Ferritin (r= - 0.28, p=0.029), monthly EPO dose (r= - 0.26, p=0.044), TGFβ (r=0.36, p=0.023), VEGF/SCr (r=0.43, p= 0.000). TGFβ correlated with SCr levels (r= - 0.32, p=0.047) but TGFβ/SCr correlated with sKlotho (r=0.36, p=0.005), IL-6 (r=0.98, p=0.000), Ferritin levels (r= - 0.28, p=0.027). VEGF did not correlate with any of our investigated data however when reported to SCr, VEGF/SCr correlated with sKlotho (r=0.34, p=0.008), monthly EPO dose (r= - 0.27, p=0.035), PWW results (r= - 0.33, p=0.034), IL-6/SCr (r= 0.43, p=0.000), sKloto/SCr (r=0.39, p=0.002). sKlotho correlated with IL-6 (see above), daily EPO dose (r= - 0.31, p=0.013). sKlotho/SCr correlated with eKt/V (r=0.25, p=0.048), TGFβ (r=0.34, p=0.034), IL-6 (as above), iPTH (r=0.26, p=0.043), Ferritin (r= - 0.27, p=0.024). Conclusion With the exception of KIM-1 our working hypothesis was confirmed and it seems that in HD patients statistics are modified if blood biomarkers (BM) are referred to predialysis serum creatinine. More research is needed in order to verify the validity and significance of our observations.

P1503A MULTICENTER STUDY OF THE CLINICAL, LABORATORY CHARACTERISTICS AND POTENTIAL PROGNOSTIC FACTORS IN PATIENTS WITH AA AMYLOIDOSIS ON HEMODIALYSIS

Abstract Background and Aims While, AL amyloidosis is more common in western countries, the most common type of amyloidosis is AA amyloidosis in eastern Mediterranean region including Turkey. Although worse prognosis has been attributed to the AL amyloidosis, AA amyloidosis can also be related to higher mortality under renal replacement therapies. However, there are no sufficient data regarding etiology, clinical presentation and prognostic factors of AA amyloidosis. The objective of our study is to evaluate the clinical, laboratory characteristics and possible predictive factors related to mortality in patients with AA amyloidosis undergoing hemodialysis (HD). Method This multicenter, cross-sectional study was a retrospective analysis of 2100 patients on HD and carried out in 14 selected hemodialysis centers throughout Turkey. Thirty-two patients with biopsy proven AA amyloidosis and thirty-two control patients without AA amyloidosis undergoing HD were included between October 2018 and October 2019. There was no significant difference between the groups in terms of the age and dialysis vintage. Causes of AA amyloidosis, treatment (colchicine and/or anti-interleukin 1 (IL) treatment; canakinumab or anakinra) and number of Familial Mediterranean Fever (FMF) attacks in the last year in case of FMF, systolic and diastolic blood pressures, biochemical values such as mean CRP, hemoglobin, serum albumin, phosphorus, calcium, PTH, ferritin, transferrin saturation, total cholesterol levels and EPO dose, erythropoietin resistance index (ERI), interdialytic fluid intake, body mass indexes, heparin dosage, UF volume and Kt/V data in the last year were collected by retrospective review of medical records. Results Prevalence of AA amyloidosis was found 1.87% in HD centers. In amyloidosis and control groups, 56% and 53% were male, mean age was 54±11 and 53±11 years, mean dialysis vintage was 104±94 and 107±95 months, respectively. FMF was the most common cause of AA amyloidosis (59.5%). All FMF patients received colchicine and the mean colchicine dose was 0,70 ±0,30 mg/day. 26,3 % of FMF patients were unresponsive to colchicine and anti-IL-1 treatment was used in these patients. In AA amyloid and control groups, ERI were 7,88±3,78 and 5,41±3,06 IU/kg/week/g/dl, respectively, (p=0.008). Additionally, higher CRP values (18,78±18,74 and 10,61±10,47 mg/L, p=0.037), lower phosphorus (4,68±0,73 mg/dL vs 5,25±1,04, p=0.014), total cholesterol (135±42 vs 174±39 mg/dL, p&amp;lt;0.01) and serum albumin (3,67±0,49 mg/dL, 4,03±0,22, p&amp;lt;0.01) were observed in patients with AA amyloidosis compared to the control group. Conclusion In this study, we found that long term prognostic factors including higher inflammation, malnutritional parameters and higher ERI were more frequent in AA amyloidosis patients under hemodialysis treatment. Figure Demographic, clinical and laboratory characteristics of patients

P1084LONG TERM EVALUATION OF THE EXPANDED HEMODIALYSIS (HDX) ON DIALYSIS ADEQUACY, ANEMIA AND QUALITY OF LIFE

Abstract Background and Aims The High-Flux (HF) dialyzer in standard hemodialysis (HD) allow the removal of a wider spectrum of uremic toxin. However, the HD can remove mostly low molecular weight solutes while the HDF can remove solutes around 15kDa, so-called Middle Molecules (MM), improving morbidity and mortality by exchange volumes &amp;gt;23L per session. The new medium cut-off (MCO) filter Theranova® is designed to expand the removal of toxins up to 45kDa in HD compared to HF membranes (HemoDialysis eXpanded, HDx) even with conventional blood flows and without exchange fluid infusion. The aim of this study is to evaluate the performance of HDx and its impact on anemia and quality of life (QoL) in haemodialysis patients. Method 11 stable HDs patients were enrolled (M/F 8/3, age 70.8±9) with Qb ≤300 ml/min in a 12 months observational case-control study. Each patient was evaluated first with HF filter (T0) and then in HDx for 12 months (T12). At T0-T6-T12 were evaluated: urea, phosphate (P), beta2-microglobulin (B2m), myoglobin (Myo), free light-chains k and λ (FLC- K and FLC- λ), C-Reactive Protein (CRP), hemoglobin (Hb) and albumin as well. Furthermore Kt/V, dose of EPO, ERI and SF-36 questionnaire were evaluated at the beginning and end of observation. We treat HD patients accordingly to the KDIGO Guideline for Anemia in CKD. The values have been reported as mean ±SD. Results HDx (Qb = 275 ± 41 ml/min, TT 215 ± 21 m) shows a significant increase in KT/V (T0 1,33 ± 0,19; T12 1,57 ± 0,16; p = 0.001) with relevant RR of: Urea 73.5%; P 58.4%; B2m 66,1 % (p&amp;lt; 0.05); Myo 55,1% (p&amp;lt; 0.05); FLC-k 64.1 % (p&amp;lt; 0.05); FLC-λ 59.9% (p&amp;lt; 0.05). There is a significant reduction at 12months for PCR (Tab.1). HDx reduced ERI [T0 10.1 ± 11.2; T6 4.1 ± 5.3 (p &amp;lt;0.05); T12 6±9.8] and EPO dose [T0 8182 ± 9141; T6 3545 ± 4547 (p &amp;lt;0.05); T12 5273±8912], keeping the Hb unchanged. QoL is significantly improved (ISF: T0 27.3 ± 10.1; T12 40.2 ± 8.4 p = 0.0001) (ISM: T0 43.8 ± 14.2; T12 51.1 ± 9.8 p = 0.001). Conclusion HDx effectively removes uremic toxins up to 45kDa, even with Qb &amp;lt;300 ml/min, without reducing serum albumin and with interesting results on inflammation. Reduction of ERI and improvement of QoL are encouraging and suggest the use of HDx even in patients who cannot benefit from convective techniques because of vascular access or intolerance to high volumes of exchange.

P1423INCREASED BLOOD FLOW RATE IN HIGH-FLUX HAEMODIALYSIS - IS IT RELEVANT FOR PHOSPHORUS REMOVAL IN HAEMODIALYSIS PATIENTS?

Abstract Background and Aims High-flux haemodialysis (HD), beside other uremic solutes harmful for patients, controls the level of phosphorus, major factor for HD-related morbidity and mortality. First line in phosphorus control in HD patients is dietary phosphorus intake reduction, whereas its’ removal is undervalued by hemodialysis. The primary objective was to analyse whether change in the rate of blood flow is relevant in phosphorus removal in HD patients. Second objective was to evaluate other variables impacted by higher blood flow rates. Method Retrospective study was conducted enrolling 80 patients from a single center in a period of 12 months. In the first six months, all patients were on lower blood flow rate (LBFR group) than the same patient group was switched to a higher blood flow rate in the following six months (HBFR group). Demographic, clinical and laboratory variables were collected and intra/inter-patient group analysis was performed. Results Forty-seven patients were male, and 41.3% were female. Mean age of the study population was 61.2±13.47 years (males 60.3±13.38, females 62.4±13.68). Mean dialysis vintage was 63.31±66.57 months. The average real blood flow rate in LBFR group was 290.75±19.65 ml/min (median 285.34 ml/min), 344.87±9.12 ml/min in HBFR group (median 339 ml/min), p=0.0002. The level of phosphorus in LBFR group was 1.52±0.03 mmol/L, and 1.45±0.04 in HBFR group, p=0.007. Other variables that significantly showed improvement following the increase of blood flow rate were eKT/V (p=0.0006), urea clearance (p=0.02) and transferrin saturation (p=0.04). The level of post-HD urea (p=0.02) and body surface area (p=0.04) were decreased. Weekly EPO dosage decrease in HBFR group (p=0.02) was not correlated with increased iron sucrose administration (LBFR group 59.99±36.18 mg/wk, HBFR group 65.8±28.7, p=0.45). There were no significant changes related to cardiac function; systolic (p=0.44) and diastolic pressure (p=0.36), mean arterial (p=0.43) and pulse pressure (p=0.26) remained in reference range. Also, the average dose of calcium-based phosphate binders did not change significantly (p=0.34). Conclusion This study showed that increased blood flow rate in HD patients reduces phosphorus and EPO consumption, improves urea clearance without significant impact on cardiac function and calcium overload with calcium-based phosphate binders.

P0854THE ENDOGENOUS ERYTHROPOIETIN EXPRESSION IN CKD PATIENTS AT HIGH ALTITUDE: DATA FROM TIBETAN PLATEAU

Abstract Background and Aims Some studies have shown that higher altitude was associated with lower EPO doses and higher hematocrit levels in HD patients. Our pre-study also confirmed that the higher the altitude, the lower the EPO resistance index [weekly weight-adjusted dose of erythropoietin (IU/kg/week) divided by Hb concentration (g/dl)]. Possible explanations included that patients at higher altitude produce more endogenous EPO or they respond more efficiently to EPO than patients at lower altitude. The aim of this study was to determine whether endogenous EPO production was up-regulated in CKD patients at high altitude. Method Three cohorts from different altitude were compared. Among them, 58 CKD patients were from Tibet Autonomous Region People's Hospital (3650m above sea level, recruited between March 2019 and July 2019. The other two cohorts were from the literatures. [1,2] The exclusion criteria included patients under EPO substitution or those with acute renal failure, polycystic kidney disease, renal carcinoma or polycythemia. The subjects were then stratified into groups according to the CKD stage. EPO concentrations were determined by using electrochemiluminescent immunoassay. Change of endogenous EPO levels with altitude by CKD stage was studied. Results The characteristics of the Tibet cohort were shown in table 1, the other two can be found in references. In Tibet cohort, there was a significant correlation between serum EPO concentrations and CKD stages as well as eGFR. The equation derived from liner regression analysis was EPO (mIU/ml) =-1.941*CKD stage+17.67 (r2 = 0.093, P = 0.020) and log EPO (mIU/ml) =-0.0002311*eGFR (ml/min/1.73m2) + 1.025 (r2 = 0.097, P = 0.017). Serum EPO concentrations dropped with decreasing of eGFR, see in Figure 1. Normally there was an exponential relation between hemoglobin and endogenous EPO in healthy people. The correlation was attenuated and even absent in CKD patients. In Tibet cohort, there was no linear relation between hemoglobin and endogenous EPO (r2 &amp;lt; 0.001, P =0.907), see in Figure 2. Compared with the other two cohorts at lower altitude, the average EPO concentration of Tibetan patients was higher in CKD stage one, however, it decreased quickly with increasing stages of CKD. The average EPO concentration were even lower in CKD stage two to five, see in Figure 3. Conclusion Endogenous EPO production was only up-regulated in patients with normal renal function at high altitude, those with impaired renal function failed to produce more EPO. Our results suggest that the possible explanation for CKD patients at high altitude had better EPO responsiveness is that they respond more efficiently to EPO other than they produce more endogenous EPO.

Mixed hemodiafiltration reduces erythropoiesis stimulating agents requirement in dialysis patients: a prospective randomized study.

Improved responsiveness to erythropoiesis stimulating agents (ESAs) in patients on on-line post-dilution hemodiafiltration (Post-HDF) compared with conventional hemodialysis (HD) was reported by some authors but challenged by others. This prospective, cross-over randomized study tested the hypothesis that an alternative infusion modality of HDF, mixed-dilution HDF (Mixed HDF), could further reduce ESAs requirement in dialysis patients compared to the traditional Post-HDF. One-hundred-twenty prevalent patients from 6 Dialysis Centers were randomly assigned to two six-months treatment sequences: A-B and B-A (A, Mixed HDF; B, Post-HDF). Primary outcome was comparative evaluation of ESA (darbepoetin alfa) requirement and ESA resistance. Treatments efficiency, iron and vitamins status, inflammation and nutrition parameters were monitored. In sequence A, darbepoetin requirement decreased during Mixed HDF from 29.5 to 23.7µg/month and increased significantly during Post-HDF (32.3µg/month at 6th month) while, in sequence B, it increased during Post-HDF from 38.2 to 43.7µg/month and decreased during Mixed HDF (23.9µg/month at 6th month). Overall, EPO doses at 6months on Mixed and Post-HDF were 23.8 and 38.4µg/month, respectively, P < 0.01. A multiple linear model confirmed that Mixed HDF vs Post-HDF reduced significantly ESA requirement and ESA resistance (P < 0.0001), by a mean of 29% (CI 23-35%) in the last three months of the observation periods. Mixed HDF decreased darbepoetin-alfa requirement in dialysis patients. This might help preventing the untoward side effects of high ESA doses, besides having a remarkable economic impact. Additional evidence is needed to confirm this potential benefit of Mixed-HDF.

Effect of Intradialytic Exercise on Physical Performance and Cardiovascular Risk Factors in Patients Receiving Maintenance Hemodialysis: A Pilot and Feasibility Study

Introduction: Although intradialytic exercise is considered a form of “nonpharmacological medicine” for patients receiving maintenance hemodialysis (MHD), this practice has not been widely implemented in most dialysis centers because of clinical limitations. We, therefore, aimed to design an intradialytic exercise training program to improve the implementation of this practice and determine its impact on physical performance and cardiovascular risk factors in patients receiving MHD. Methods: A total of 132 MHD patients at 4 outpatient dialysis units were enrolled and assigned randomly into exercise (n = 67) and control groups (n = 65). During a 2-year period, patients in the exercise group participated in 20-min exercise training sessions within dialysis sessions on 3 days per week. All patients underwent assessments of physical function (6-min walk test) and cardiovascular risk factors (blood pressure [BP], total cholesterol [TC], low-density lipoprotein [LDL], high-sensitivity C-reactive protein [hsCRP], albumin [Alb], hemoglobin [Hb], and erythropoietin [EPO] dose) at the baseline and annually thereafter. Results: Of the participants, 50.8% had completed the study after 2 years. No statistically significant intragroup or intergroup differences were observed in the measures of 6MD, BP, TC, hsCRP, Alb, Hb, and EPO dose. Conclusion: The results suggest that although this low-intensity, nonprogressive intradialytic exercise program may be practical, it was not sufficient to improve physiological function and reduce cardiovascular disease risk factors in patients receiving MHD.

Effects of changes in adult erythropoietin dosing guidelines on erythropoietin dosing practices, anemia, and blood transfusion in children on hemodialysis: findings from North American Pediatric Renal Trials and Collaborative Studies (NAPRTCS).

While adult hemodialysis (HD) patients have increased morbidity with higher target hemoglobin levels, similar findings have not been demonstrated in pediatric patients. We evaluated changes in transfusions, anemia frequency, and erythropoietin (epo) dosing among pediatric HD patients before, during, and after implementation of federal dialysis payment policies regarding epo dosing for adult HD patients. This is a retrospective cohort study of pediatric HD patients enrolled in NAPRTCS. We evaluated need for transfusion, anemia, median hemoglobin, and median epo dose 6 months after starting HD in 3 eras: baseline (2003-2007), implementation (2008-2011), and post implementation (2012-2016). We used multivariate logistic regression models to evaluate potential differences in transfusion across the eras. Six months after dialysis initiation, 12.6% of patients required transfusion pre-implementation, 17.9% during implementation, and 15.5% post implementation. Anemia occurred in 17.4% of patients pre, 23.5% during, and 23.8% post implementation, with median hemoglobin levels of 11.9 g/dL pre, 11 g/dL during, and 11 g/dL post implementation. Epo use was high across all 3 eras, but epo dosing decreased during and post implementation, despite more anemia during these periods. Odds of transfusion in implementation era compared with pre-implementation was 1.75 (95% CI 1.11-2.77) and odds of transfusion in post implementation era compared with pre was 1.19 (95% CI 0.71-1.98), controlling for age, race, gender, and prior transplant status. During and following implementation of adult epo dosing guidelines, transfusion and anemia frequency increased in pediatric HD patients. Ideal target hemoglobin levels for pediatric dialysis patients warrant further study.

SAT-036 ERYTHROPOIESIS STIMULATING AGENT HYPORESPONSIVENESS AND ITS ASSOCIATION WITH MORTALITY AND HOSPITALISATION

In patients with CKD, higher erythropoiesis stimulating agents (ESA) dose might cause higher mortality and increased cardiovascular complications. Hyporesponsiveness to ESA treatment is a known predictor of poor clinical outcomes in haemodialysis (HD) patients. Poor outcomes could be the result of high ESA dosage required in these groups or patient related cause of hypo-responsiveness or a combination of both. We sought to examine whether high erythropoietin resistance index (ERI) was associated with increased all-cause mortality and hospitalisation among incident HD patients. Incident HD patients between January 2010 and December 2016, who completed six months of HD were included in this retrospective observational cohort study. Patients were followed up for one year from the index date (last day of 6 months exposure period) until first of the following – death, withdrawal or end of study (Dec 31, 2017). The main predictor variable was ESA responsiveness measured by ERI (IU/kg/week/g/dl) which was defined as average weekly weight-adjusted EPO dose per average haemoglobin concentration. Patients were divided into 2 groups based on ERI quartiles - ESA hyporesponsive (4th quartile, ERI >15.25+) and ESA responsive group (1st, 2nd and 3rd quartile combined, ERI < 15.25). ESA responsiveness was also assessed by a combination of ESA dosage (high: ≥ median value of ESA dose or low: < median value of ESA dose) and haemoglobin levels (high: ≥ 10 g/dl or low: <10 g/dl). Patients were then divided into 4 groups with low-dose ESA therapy and high haemoglobin (Hb) level as reference category.Primary outcomes were all-cause mortality and hospitalisation during the one year follow-up. Cox regression and Negative binomial regression models were used to determine associations with mortality and hospitalisation among the ERI groups. Binary logistic regression model was used to define the predictors of high ERI. A total of 2302 incident HD patients (mean age 60.1 ± 11.4 years, 56.2% male, 59% Chinese and 69.9% with diabetes as cause of ESRD) were included in the study. During the mean follow-up time of 0.95 ± 0.16 years, 113 (4.9%) patients died. The median EPO dose and mean ERI were 113.9 (IQR, 77.8 to 154.8) IU/kg/week and 12.1± 6.4 IU/kg/week/g/dl respectively. The ESA hyporesponsive group (ERI >15.25+) were more likely to be females, have low albumin, low BMI, low SGA scores and low transferrin saturation % levels but higher KT/V and ferritin levels compared to the ESA responsive group (p<0.001). ESA hyporesponsive group (ERI>15.25+) had 83% higher risk of all-cause mortality (aHR 1.83, 95% CI 1.20 – 2.79, p=0.005) after adjusting for potential confounders. HD patients with high-dose EPO and low Hb levels (ESA hyporesponsive) had significantly higher risk of mortality (aHR 2.42, 95% CI 1.41 – 4.19, p=0.001). The high ERI group also had 36% higher incidence of hospitalisation (IRR 1.36, 95% CI 1.20 – 1.54, p<0.001) compared to low ERI group. The independent predictors of high ERI were female gender, low albumin, high ferritin, low transferrin saturation %, low BMI, high KT/V, high acuity status and increased hospital admissions in the exposure period.View Large Image Figure ViewerDownload Hi-res image Download (PPT) High ERI levels are associated with increased risk of all-cause mortality and hospitalisation in incident HD patients. Lack of data on inflammatory markers is a study limitation.