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J W Eschbach

Publications and source records attributed to J W Eschbach.

At least 37 records · Page 2Linked to original sources

Treatment of the anemia of chronic renal failure with recombinant human erythropoietin.

The anemia of chronic renal failure can now be effectively treated with recombinant human erythropoietin when given in adequate doses. This hormone replacement therapy is associated with significant clinical benefits but it requires adequate iron stores for maximal effectiveness, it may result in elevation in diastolic blood pressure, and the response may be blunted by the presence of infection or inflammation.

Anemia↗

The use of recombinant human erythropoietin (rHuEpo) in humans.

Recombinant human erythropoietin (rHuEpo) has now been in clinical trials for over four years. rHuEpo has been shown to be nearly uniformly effective in correcting the anaemia of patients on haemodialysis or patients with progressive chronic renal failure not yet on dialysis. rHuEpo has been shown to be effective in increasing the ability of individuals to donate blood for self-use and to increase the haematocrit in patients with rheumatoid arthritis. Preliminary results indicate that rHuEpo will decrease transfusion requirements of patients with the acquired immune deficiency syndrome who are anaemic. Trials in patients with anaemia associated with cancer or myelodysplastic syndromes are in early stages. rHuEpo will have a major impact as a therapeutic agent, particularly in patients with renal disease.

Acquired Immunodeficiency Syndrome↗

Recombinant human erythropoietin in anemic patients with end-stage renal disease. Results of a phase III multicenter clinical trial.

STUDY OBJECTIVE: To determine the effectiveness and safety of recombinant human erythropoietin (rHuEpo). PATIENTS: Hemodialysis patients (333) with uncomplicated anemia (hematocrit less than 0.30). All received rHuEpo intravenously, three times per week at 300 or 150 U/kg body weight, which was then reduced to 75 U/kg and adjusted to maintain the hematocrit at 0.35 +/- 0.03 (SD). RESULTS: The baseline hematocrit (0.223 +/- 0.002) increased to 0.35, more than 0.06 over baseline within 12 weeks in 97.4% of patients. Erythrocyte transfusions (1030 within the 6 months before rHuEpo therapy) were eliminated in all patients within 2 months of therapy. Sixty-eight patients with iron overload had a 39% reduction in serum ferritin levels after 6 months of therapy. The median maintenance dose of rHuEpo was 75 U/kg, three times per week (range, 12.5 to 525 U/kg). Nonresponders had complicating causes for anemia, myelofibrosis, osteitis fibrosa, osteomyelitis, and acute or chronic blood loss. Adverse effects included myalgias, 5%; iron deficiency, 43%; increased blood pressure, 35%; and seizures, 5.4%. The creatinine, potassium, and phosphate levels increased slightly but significantly. The platelet count increased slightly but there was no increase in clotting of vascular accesses. CONCLUSIONS: The anemia of hemodialysis patients is corrected by rHuEpo resulting in the elimination of transfusions, reduction in iron overload, and improved quality of life. Iron stores and blood pressure must be monitored and treated to maintain the effectiveness of rHuEpo and to minimize the threat of hypertensive encephalopathy.

Adolescent↗

Treatment of the anemia of progressive renal failure with recombinant human erythropoietin.

To examine the effects of erythropoietin on the anemia of chronic renal disease and on the rate of renal deterioration, we administered recombinant human erythropoietin to 17 patients with anemia and progressive renal failure who did not yet require dialysis (serum creatinine level, 353 to 972 mumol per liter [4.0 to 11.0 mg per deciliter]). The dose of erythropoietin (50 to 150 units per kilogram of body weight) was adjusted according to the hematocrit response. In all 17 patients the anemia responded to erythropoietin. The median hematocrit increased from 0.27 to 0.37. The rate of the response depended on the initial erythropoietin dose and was similar to that observed in patients who were on dialysis. Hypertension was present in 14 patients before therapy, developed during therapy in 2 of the normotensive patients, and worsened in 9 patients, who required additional antihypertensive medications. The rate of the decline in renal function, as measured by serial determination of the reciprocal of the serum creatinine level, did not change significantly as the hematocrit rose (P = 0.78 by the paired t-test) during erythropoietin therapy. All the patients reported improvements in appetite, activity level, and sense of well-being. We conclude that erythropoietin therapy is effective in correcting the anemia of patients with progressive renal failure without affecting renal function, although it may be associated with an increase in blood pressure.

Adult↗

Guidelines for recombinant human erythropoietin therapy.

Extensive testing has proven that recombinant human erythropoietin (r-HuEPO; EPOGEN [epoetin alfa], AMGEN Inc, Thousand Oaks, CA) corrects the anemia of end-stage renal disease and eliminates the need for transfusions in virtually all patients. Patients whose hematocrit levels are less than 0.30 or who are transfusion dependent are candidates for therapy. A dosage of 50 to 150 U/kg body weight intravenously three times a week produces an increase in hematocrit by approximately 0.01 to 0.02 per week. Once the hematocrit reaches 0.30 the dose is adjusted so that a target hematocrit of 0.32 to 0.38 is maintained. Eighty percent of patients need maintenance doses of r-HuEPO of less than or equal to 150 U/kg; the other 20% of patients require larger doses. Reasons for poor responses include iron deficiency, inflammation due to surgery or infection, and osteitis fibrosa. Most patients require iron supplementation to prevent functional iron deficiency. BP increased in one third of patients, and in 3% seizures occurred during the initial phase of therapy, often associated with a sudden increase in BP. This hypertension can be controlled with medication. Increased dialyzer clotting may occur, which is prevented when heparin doses are adjusted, and dialyzer solute clearances may decrease slightly. Treatment with r-HuEPO does not elicit an antibody response. The mechanism of action of r-HuEPO is identical to that of natural erythropoietin, and therefore is an appropriate therapy for the long-term management of anemia in chronic renal failure.

Anemia↗

Recombinant human erythropoietin: implications for nephrology.

The pathophysiology of the anemia of chronic renal failure (CRF), erythropoietin physiology, the characteristics of recombinant human erythropoietin, and the results of nearly 2 years of therapy with this product in hemodialysis patients are detailed in this review. This anemia is primarily an endocrine deficiency state corrected by the hormone erythropoietin. Correction of the anemia eliminates transfusions and their associated risks, improves physical endurance, and results in healthier patients beginning dialysis. Adequate support services will be necessary to maximize patient rehabilitation and employment potential. Further research is needed to better understand erythropoietin physiology and metabolism, and the impact of uremia on end organ function in the absence of anemia.

Anemia↗

The anemia of end-stage renal disease: hematopoietic progenitor cell response.

Patients with the anemia of end-stage renal disease (ESRD) fail to display an appropriate compensatory increase in red cell production. In order to investigate the extent to which the impaired erythropoietic response is determined at the progenitor cell level, we determined the frequencies of marrow colony-forming cells in 11 anemic and 3 non-anemic, dialysis-dependent ESRD patients and 10 healthy individuals. In addition, we measured serum levels of erythropoietin (Epo) by radioimmunoassay. There were no significant differences (P greater than 0.1) between normal and ESRD groups in the frequencies of primitive or late erythroid (BFU-E and CFU-E, respectively), granulocyte-macrophage, and megakaryocyte progenitors, CFU-E/BFU-E ratios, or serum Epo levels. In contrast, 5 non-uremic patients with chronic anemia comparable in severity to the anemic ESRD patients had serum Epo levels and CFU-E/BFU-E ratios that were significantly increased (P less than 0.05 and P less than 0.001, respectively) in comparison to the normal controls and ESRD patients. Pre-dialysis serum and plasma from both ESRD groups were as supportive of autologous erythroid and non-erythroid colony growth in vitro as normal serum and plasma; inhibition was not observed. We conclude that the relative numbers of erythroid and non-erythroid progenitors and the majority of serum Epo levels are unchanged from normal in patients with the anemia of ESRD. However, their normal CFU-E/BFU-E ratio reflects an inadequate compensatory erythropoietic response due to their inability to appropriately increase Epo production in response to anemia. Inhibitors of autologous erythroid colony formation were not detected in ESRD serum.(ABSTRACT TRUNCATED AT 250 WORDS)

Anemia↗

Correction of the anemia of end-stage renal disease with recombinant human erythropoietin. Results of a combined phase I and II clinical trial.

We administered recombinant human erythropoietin to 25 anemic patients with end-stage renal disease who were undergoing hemodialysis. The recombinant human erythropoietin was given intravenously three times weekly after dialysis, and transfusion requirements, hematocrit, ferrokinetics, and reticulocyte responses were monitored. Over a range of doses between 15 and 500 units per kilogram of body weight, dose-dependent increases in effective erythropoiesis were noted. At 500 units per kilogram, changes in the hematocrit of as much as 10 percentage points were seen within three weeks, and increases in ferrokinetics of three to four times basal values, as measured by erythron transferrin uptake, were observed. Of 18 patients receiving effective doses of recombinant human erythropoietin, 12 who had required transfusions no longer needed them, and in 11 the hematocrit increased to 35 percent or more. Along with the rise in hematocrit, four patients had an increase in blood pressure, and a majority had increases in serum creatinine and potassium levels. No organ dysfunction or other toxic effects were observed, and no antibodies to the recombinant hormone were formed. These results demonstrate that recombinant human erythropoietin is effective, can eliminate the need for transfusions with their risks of immunologic sensitization, infection, and iron overload, and can restore the hematocrit to normal in many patients with the anemia of end-stage renal disease.

Adult↗

Hematopoietic inhibitors in chronic renal failure: lack of in vitro specificity.

To assess the potential role of retained inhibitors in the pathogenesis of the anemia of chronic renal failure, we have studied simultaneously the effects of increasing concentrations of normal or uremic sera on the growth of erythroid colonies (from CFU-E), granulocyte-macrophage colonies (from CFU-GM), and megakaryocytic colonies (from CFU-Meg) in mouse marrow cell cultures. As compared to normal human serum, increasing concentrations of uremic sera induced a dose-dependent inhibition in the growth of all colony types. Significant correlations (P less than 0.001) were found between the ability of any individual uremic serum to support CFU-E, CFU-GM, and CFU-Meg growth, and, whenever significant inhibition was seen, all three progenitor types were affected. The inhibitory effect on CFU-E growth was significantly greater (P less than 0.01) in patients with serum creatinine concentrations greater than or equal to 7 mg/dl, but no correlation was found between CFU-E inhibition and hematocrit. Likewise, inhibition of CFU-GM and CFU-Meg growth was not associated with leukopenia or thrombocytopenia, respectively. Sera from patients undergoing chronic intermittent hemodialysis were assayed before and after one hemodialysis session. In each case, the degree of inhibition of CFU-E and CFU-GM growth decreased after hemodialysis, but improvement in CFU-Meg growth was more variable. These data indicate that uremic sera contain dialyzable inhibitors of in vitro hematopoiesis which increase with the severity of renal dysfunction, but these inhibitors lack specificity. If uremic inhibitors of erythropoiesis are of pathophysiologic significance in vivo, there must be unrecognized repair mechanisms for granulopoiesis and thrombopoiesis.

Animals↗