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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Age-density fractionation, in-vitro erythrophagocytosis, and enumeration of membrane-bound antibodies were monitored for circulating red blood cells (RBC) from five anemic patients with myelodysplastic syndromes (MDS), in relation to administration of recombinant human erythropoietin (rhEPO). The density distribution patterns of erythrocytes from the patients prior to treatment were in accordance with their inability to produce compensating levels of circulating RBC. The complete response of one patient to rhEPO and partial responses of two other patients were accompanied by shifts to larger proportions of low density (young) RBC. In vitro phagocytosis of density-fractionated RBC from the complete responder was similar to those of age-matched non-anemic donors. Elevated erythrophagocytosis prior to rhEPO administration was observed for the partial responders and further increased during treatment in one, suggesting the stimulation of abnormal progenitors producing highly defective erythrocytes. There was no correlation between levels of erythrophagocytosis and RBC membrane-bound immunoglobulins in this group of patients. Our findings suggest that density distribution analysis of circulating RBC coupled with in vitro erythrophagocytosis may provide useful predictive tools for selecting potential responders to rhEPO administration among anemic MDS patients.
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PMID:Characterization of circulating erythrocytes from myelodysplastic patients treated with recombinant human erythropoietin. 837 83

We studied the efficacy of high doses (100,000 IU intravenously (IV)/twice a week) of human recombinant erythropoietin (rHuEpo) in patients with transfusion dependent myelodysplastic syndromes (MDS). Rationale for such dose of IV Epo was the poor in vitro response of MDS erythroid progenitors (CFU-E) to physiological concentrations of Epo, and the usual high endogenous serum Epo levels of MDS patients. Seventeen patients (nine males, eight females) were included, five refractory anaemia (RA), six RA with blasts excess (RAEB), five RA with ringed sideroblasts (RARS). Tolerance was good, except in three patients who experienced severe flu-like syndrome after Epo injection. None of the patients showed hypertension or developed anti rHuEpo antibodies. Three patients (17.6%) with RAEB had 35-60% reduction of transfusion requirements. No progression of disease occurred. Percentage of erythroblasts, endogenous baseline Epo level and in vitro cultures of erythroid progenitors did not correlate with response to Epo treatment. This study shows that very high IV doses induce only seldom and partial improvement in the status of transfusion dependent MDS. This rate of response, not higher than described with lower dosage, probably represents the maximum expectable response to rHuEpo in this category of patients.
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PMID:High doses of intravenous recombinant erythropoietin for the treatment of anaemia in myelodysplastic syndrome. 839 23

The red-cell mass is continuously adjusted to the optimal size for its function as an oxygen carrier by messages transmitted to the bone marrow from an oxygen sensor in the kidney. These messages are mediated by the hormone erythropoietin. Erythropoietin is a glycoprotein growth factor synthesized by cells adjacent to the proximal renal tubule in response to signals from a renal oxygen-sensing device, probably a heme protein (1). In the bone marrow, erythropoietin binds to and activates specific receptors on the erythroid progenitor cells (2). In the presence of this erythropoietin-receptor complex the progenitor cells continue their predestined development into mature erythrocytes. Erythropoietin was the first hemopoietic growth factor to be molecularly cloned in 1985 (3). Our understanding of the biology and physiology of erythropoietin has been considerably improved with the advent of recombinant human erythropoietin (rHuEpo). During the past 7 years, rHuEpo has undergone extensive testing in clinical trials. It has been approved for treatment of the anemia of chronic renal failure, both in progressive renal failure and endstage renal failure (ESRD). In these instances, the administration of rHuEpo has been used in effect as a substitutive therapy, since patients' erythropoietin levels are very low despite severe anemia, due to the failure of affected kidneys to produce adequate amounts of the hormone. However, the application of rHuEpo has now moved largely from the primitive indication of renal diseases, and the hormone is currently under study in a number of anemic states of different etiologies, even with relatively high serum erythropoietin levels. Among these, some of the best documented indications are the anemia associated with malignancies, either due to neoplastic bone marrow infiltration or to chemotherapy-related myelosuppression, the anemia of myelodysplastic syndromes and AIDS, the anemia of chronic inflammatory diseases, prematurity, and bone marrow transplantation (4). The purpose of this review is to provide a summary of our present knowledge regarding rHuEpo therapy for the anemia of renal failure. We provide some clues for the correct use of rHuEpo in the treatment of the anemia of chronic inflammatory diseases. In addition, we address a series of new issues in the attempt to better understand the relationship between erythropoietin and liver disease.
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PMID:Erythropoietin and the anemia of chronic diseases. 840 91

The safety and efficacy of recombinant human erythropoietin (epoetin alpha) were investigated in anemic patients with myelodysplastic syndrome (MDS) whose hemoglobin (Hb) concentration was less than 10g/dl. Epoetin alpha was given subcutaneously daily at a dose of 3,000IU/body for two weeks and the dosage was increased to 6,000IU, 12,000IU, and 24,000IU at two week interval when the increment of Hb was insufficient. Patients in whom the Hb concentration increased by more than 1g/dl or whose blood transfusion requirement reduced to below 50% were considered to be cases of effective treatment. The overall rate of effectiveness was 20.6% (7/34). Response to epoetin alpha treatment was better in patients with refractory anemia (RA) or RA with ringed sideroblasts (RARS). The high dose epoetin alpha (12,000-24,000IU/body/day) was required for the patients to respond. These results suggest that the high dose subcutaneous epoetin alpha treatment is effective for the anemia associated with MDS in terms of increasing Hb concentration and reducing blood transfusion.
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PMID:[Phase II clinical study of recombinant human erythropoietin on the anemia of myelodysplastic syndrome]. 841 47

Myelodysplastic syndrome is a frustrating disorder, which until recently lacked effective treatment. Patients usually succumb to infection, bleeding complications, or progression to acute leukemia. Recombinant cytokines such as granulocyte macrophage-colony stimulating factor, granulocyte-colony stimulating factor, interleukin-3, and erythropoietin have been used to ameliorate the cytopenias associated with this disease. Small clinical trials in myelodysplastic syndrome patients, using cytokines with myeloid activity (G-CSF, GMCSF, IL-3), have shown consistent elevations in the white blood cell counts with little success in elevating hemoglobin or platelets. Erythropoietin is able to increase the hemoglobin in a small group of myelodysplastic syndrome patients. Future trials using combinations of these cytokines may lead to multilineage effects.
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PMID:Will cytokines alter the treatment of myelodysplastic syndrome? 842 96

Haematological complications frequently occur in patients treated with chemotherapeutic agents. The degree and duration of bone marrow suppression depends upon the type of agent used. In general, agents that are cell cycle phase-specific tend to cause early myelosuppression with rapid marrow recovery, as compared to the non-phase-specific agents. Host factors including patient age, nutritional status, marrow infiltration or damage, and hepatic and renal function also affect haemotoxicity. Chemotherapeutic agents suppress proliferating or potentially proliferating precursors of neutrophils, platelets and red blood cells to the same extent. With most drugs, neutropenia tends to be dose limiting and more severe than thrombocytopenia. Because of the longer life span of red blood cells, severe anaemia is rarely a problem. The management of myelosuppression is multifaceted, and consists of aggressive antibiotic therapy to treat or prevent the infections that occur with neutropenia, as well as red blood cell and platelet transfusion support to correct anaemia and prevent bleeding. The role of the haemopoietic growth factors including erythropoietin, colony-stimulating factors and the interleukins is currently being evaluated in clinical trials. Haemolytic uraemic syndrome, haemolytic anaemia and therapy-induced myelodysplasia and/or acute leukaemia are uncommon and potentially severe complications of chemotherapeutic agents.
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PMID:Adverse haematological complications of anticancer drugs. Clinical presentation, management and avoidance. 845 62

Sixteen patients (ages 53 to 85) with myelodysplastic syndrome (MDS) were treated with recombinant human erythropoietin (rHuEPO) to observe its effects on hematopoiesis. All were transfusion dependent and had Hb levels less than 9.0 g/dl and less than 10% marrow blasts. Eight patients had refractory anemia (RA), one had refractory anemia with excess blasts (RAEB), and seven had refractory anemia with ringed sideroblasts (RARS). A response was defined as an increase in Hb by greater than 2 g/dl and/or a decrease in transfusion requirement by greater than 50%. Patients were considered to be evaluable if on study greater than two months. Three of thirteen evaluable patients had a response. One patient with RA had a sustained trilineage hematologic response with no evidence of disease progression. None of the patients had trouble with hypertension or with thrombotic events. This suggests than an occasional patient with MDS will respond to rHuEPO. In some patients, this may be beneficial clinically.
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PMID:Recombinant human erythropoietin (rHuEPO) for treatment of myelodysplastic syndrome. 845 81

It has been recently demonstrated that erythropoietin increases the haemoglobin levels in anemia secondary to chronic renal failure. Moreover some recent experiences also suggested a possible role in the treatment of MDS. From April 1990 to April 1992, 23 patients (16 males and 7 females, median age 63.5 years) affected with low risk myelodysplastic syndrome (MDS) were treated with recombinant human erythropoietin (rHuEPO) to ameliorate Hb levels and transfusional requirement. All patients received high doses of rHuEPO (800 U/Kg weekly s.c. in 2-3 divided doses, for 3 months). A complete remission, defined as stable normalization of Hb level, was achieved in 1/23 patients. This patient had refractory anemia, by FAB criteria. A partial response, defined as stable increase of Hb levels > or = 1 g/dl and/or reduction of transfusional requirement > or = 50% lasting at least 3 months, was achieved in 7/23 patients. Patients with a partial response received rHuEPO at increased dosages (1200 U/Kg weekly s.c. 2-3 times): 1/7 achieved a complete response, 4/7 remained stable and 2/7 decreased to pre-therapy Hb value. These results suggest that rHuEPO may be a promising therapeutic tool for some MDS patients.
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PMID:Is recombinant human erythropoietin treatment in myelodysplastic syndromes worthwhile? 847 5

Recombinant human erythropoietin (rhEpo) was administered to 14 patients with myelodysplastic syndrome (MDS) and seven patients with aplastic anemia (AA). In 19 patients, doses of 6000 units were given intravenously three times a week (t.i.w.) with the dose being doubled up to 24,000 units every 8 weeks until a response was obtained. RhEpo was given subcutaneously in two patients. Seven patients, four with MDS and three with AA, showed a significant response with an increase of hemoglobin concentration during therapy. The response occurred at doses of 12,000 units in five and 24,000 units in two patients. Responding patients with both MDS and AA had a relatively low serum Epo (s-Epo) level prior to Epo therapy. MDS responders had either refractory anemia (RA) or RA with ring sideroblasts (RARS), while two of the Epo responders in AA had a severe form of the disease. However, since some of the Epo responders had a high initial s-Epo concentration, a high s-Epo level does not preclude the use of rhEpo. Serial determination of s-Epo levels showed a progressive decline in six of the seven responders even when they were on rhEpo therapy, while the s-Epo levels remained elevated or further increased with time in most nonresponders. RhEpo was well tolerated by all patients. The results suggest that rhEpo is a safe and effective treatment for a certain proportion of patients with MDS and AA. Moreover, serial determination of s-Epo during therapy may be useful in monitoring and predicting the therapeutic effect of rhEpo.
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PMID:Serial changes in endogenous erythropoietin levels in patients with myelodysplastic syndromes and aplastic anemia undergoing erythropoietin treatment. 848 5

Serum erythropoietin (EP) concentration was measured by the recombinant EP-based radioimmunoassay and was examined to standardize the hemoglobin (Hb) related level of 144 normal control and 56 patients with iron deficiency anemia and hemolytic anemia excluding paroxysmal nocturnal hemoglobinuria. The standardization was achieved by logarithmic regression of the EP titier on Hb either by the two-phase linear form or by the third degree sigmoid form at a 95% confidence limit for each regression. The third degree regression was found to be preferable from the view point of both statistics and the negative feedback mechanism. The average and scattering of the deviation from the standard level thus determined of the disease groups indicated that the EP level is: (1) 12 fold higher than the standard level in 42 aplastic anemias (the most in excess and a few in standard). (2) three fold higher than that in 27 myelodysplastic syndromes (relatively higher dispersed state). (3) 29% of the standard level in 33 anemias associated with chronic renal failure (deficient state). (4) 105% of the extrapolated standard level in 22 polycythemia veras (standard state). The standardization of Hb-related Ep titer may provide new pathophysiological approaches in a variety of hematopoietic disorders.
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PMID:[Determination of the standard level of serum erythropoietin in relation to hemoglobin concentration]. 851 Mar 35


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