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

The measurement of erythrocyte zinc protoporphyrin (ZPP) with a hematofluorometer is known to be a simple and cost-effective method to screen iron deficiency and lead poisoning. We measured ZPP on blood samples from 201 children suffering from various diseases, which revealed that ZPP has better sensitivity and specificity for identifying iron deficiency than serum ferritin and percent transferrin saturation. ZPP levels in various anemias were also measured. ZPP rose markedly (> 200 mumol/mol heme) in untreated iron deficiency anemia and returned to normal in 3-4 months since the initiation of iron therapy. Moderate elevation of ZPP was observed in acute leukemia (at onset and during induction therapy), MDS, aplastic anemia and some other anemic conditions. These findings suggest that erythrocyte ferrochelatase may be unexpectedly affected in anemias even except lead poisoning.
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PMID:[The measurement of erythrocyte zinc protoporphyrin/heme ratio in various anemias in childhood]. 143 41

A ferrokinetic study was performed in 79 patients, 25 with absolute polycythaemia, 19 with relative polycythaemia and 35 presenting anaemia of different aetiology. The incorporation of transferrin into the erythron (ITE) was estimated on each case. The mean ITE values found in absolute primary and secondary polycythaemia and in secondary polycythaemia were, respectively, 281 +/- 85, 181 +/- 99 and 74 +/- 19 mumol/L tb/d (i.e., micromoles per litre of total blood per day). The mean ITE in iron deficiency anaemia was 110 +/- 43 mumol/L tb/d, in haemolytic anaemia this was 274 +/- 151 mumol/L tb/d, and in patients with myelodysplastic syndromes such values was 116 +/- 49 mumol/L tb/d. Significant differences were found for each group of patients with respect to a normal control group. Such findings are in accordance with the pathophysiology of the different pathologies studied. The values found in haemolytic anaemia and myelodysplastic syndromes are similar to those reported by others. The results of this study stress the advantages of evaluating the erythropoietic activity of the bone marrow by means of the ITE.
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PMID:[Incorporation of transferrin into the erythron in anemic and polycythemic conditions]. 194 36

The authors made radioisotope examinations of the erythrokinetics in 21 patients with primary myelodysplastic syndrome: refractory anaemia and sideroblastic anaemia. He investigated the importance of changes of several conventional erythrokinetic parameters as well as the turnover of transferrin molecules which is an indicator of erythropoietic activity independent on sideraemia. The author presents ferrokinetic and erythrokinetic findings associated with myelodysplastic syndrome, as described in the literature. Sideroblastic anaemia produces a typical picture during examination of the erythrokinetics, quite different from other sub-types of the disease in refractory anaemia the changes of parameters are very variable.
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PMID:[Erythrocyte kinetics in myelodysplastic syndromes]. 202 Oct 77

Erythrokinetic studies were performed on 10 patients with chronic myelofibrosis and 11 patients with myelodysplasia (MDS). Values for plasma iron turnover, marrow iron turnover, and erythron transferrin uptake were derived using two ferrokinetic models. One entailed analysis of the extended plasma iron clearance over a number of days, the other comprised analysis of the initial plasma iron clearance during the first few hours of the study. A close correlation was found between the variables quantifying total erythropoiesis (marrow iron turnover and erythron transferrin uptake) in the two methodologies. Functional classifications produced by both models and based on the values for plasma iron turnover, marrow iron turnover, and erythron transferrin uptake were compared. Both models identified functional heterogeneity in the group with myelofibrosis and functional homogeneity within the MDS group. Each method produced comparable data on erythropoiesis. The main reason for analysing the extended plasma iron clearance is to differentiate levels of effective and ineffective erythropoiesis. The short analysis presents the practical advantages associated with a one-day study. This could be further enhanced if the level of effective erythropoiesis could be clearly defined.
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PMID:Comparative ferrokinetic study with initial and extended iron clearance models. 204 99

Erythropoietic activity in patients with myelodysplastic syndrome (MDS) was evaluated by ferrokinetic measurements. Since the conventional plasma iron turnover of MDS patients increased with plasma iron levels after multiple blood transfusions, erythron transferrin uptake was chosen as a parameter of erythroid marrow activity. Although a correlation was shown between plasma iron level and plasma iron turnover (r = 0.50, 0.01 less than p less than 0.02), no correlation existed between the plasma iron level and erythron transferrin uptake (r = 0.25, p greater than 0.1). Erythron transferrin uptake, independent of plasma iron, was significantly higher in MDS patients than in normal subjects (110.6 +/- 67.6 and 67.6 +/- 18.8 mumol/l/dl, respectively; 0.01 less than p less than 0.02). An increased erythropoiesis occurring concomitantly with morphologically normal or increased erythroid cellularity was demonstrated in patients with MDS. The measurement of erythron transferrin uptake might be valuable as an accurate expression of erythroid activity in the hyperferremic state.
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PMID:Ferrokinetic evaluation of erythropoiesis in patients with myelodysplastic syndromes. 312 77

To clarify the role of transferrin receptors in cases of altered iron metabolism in clinical pathological conditions, we studied: number of binding sites; affinity; and recycling kinetics of transferrin receptors on human erythroblasts. Since transferrin receptors are mainly present on erythroblasts, the number of surface transferrin receptors was determined by assay of binding of 125I-transferrin and the percentage of erythroblasts in bone marrow mononuclear cells. The number of binding sites on erythroblasts from patients with an iron deficiency anemia was significantly greater than in normal subjects (p less than 0.01). Among those with an aplastic anemia, hemolytic anemia, myelodysplastic syndrome, and polycythemia vera compared to normal subjects, there were no considerable differences in the numbers of binding sites. The dissociation constants (Kd) were measured using Scatchard analysis. The apparent Kd was unchanged (about 10 nmol/L) in patients and normal subjects. The kinetics of endocytosis and exocytosis of 125I-transferrin, examined by acid treatment, revealed no variations in recycling kinetics among the patients and normal subjects. These data suggest that iron uptake is regulated by modulation of the number of surface transferrin receptors, thereby reflecting the iron demand of the erythroblast.
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PMID:Erythroblast transferrin receptors and transferrin kinetics in iron deficiency and various anemias. 360 65

We conducted a Phase I-II trial of recombinant human erythropoietin-beta (rhEPO) in patients with myelodysplastic syndrome (MDS). Patients with anemia and pathologically confirmed MDS were eligible for the study. Treatment consisted of rhEPO by subcutaneous injection thrice weekly for 6 weeks at one of three dose levels (100 U/kg (three patients), 200 U/kg (three patients) and 400 U/kg (14 patients)). Ferrous sulfate (325 mg po tid) was also administered if the transferrin saturation was below 30% (two patients). Patients were monitored with weekly CBC, white cell differential, and reticulocyte counts. Bone marrow examinations were performed at the conclusion of the treatment period and after a 2 week washout period. Patients who responded to therapy were continued on rhEPO at the same dose for 6 additional months. Response criteria included: 50% reduction in transfusion requirements compared with the 6 week pre-study period; doubling of reticulocyte count that was maintained on two determinations at least 1 week apart; or an increase in hemoglobin by at least 1.2 gm/dl without transfusions. Pre-treatment factors potentially predictive of response were analyzed by univariate analysis and in a multivariate fashion by classification and regression trees. Seven of the twenty patients sustained an untransfused rise in serum hemoglobin > or = 1.2 gm/dl. Four of the sixteen patients (including three of seven patients experiencing a rise in serum hemoglobin) who were transfusion-dependent prior to the study achieved a reduction or elimination of their transfusion requirements. Five of thirteen patients who received rhEPO during the extension phase had a continued response. A low baseline erythropoietin level (< 50 mU/ml) was the best predictor of hemoglobin response when controlling for other variables. rhEPO has a role in the treatment of certain patients with MDS, particularly in those whose endogenous serum erythropoietin levels are not markedly elevated.
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PMID:Therapy with recombinant human erythropoietin in patients with myelodysplastic syndromes. 793 35

The anemia of chronic disease may be viewed simply as the anemia that accompanies chronic inflammatory, infectious, or neoplastic disorders. Because these conditions are very common, the anemia of chronic disease is one of the most frequent anemias encountered, and is only second in incidence to iron-deficiency anemia. The anemia of chronic disease is primarily an anemia due to underproduction of red cells, with low reticulocyte production, and is most often a normochromic, normocytic anemia. However, in 30% to 50% of patients, the red cells are hypochromic and microcytic and, most often, the serum iron, total iron-binding capacity, and transferrin saturation are reduced in the presence of adequate iron stores. Although the differential diagnosis includes other underproduction anemias, such as those caused by vitamin and mineral deficiencies, renal failure, endocrinopathies, and myelodysplasia, it generally is easily distinguished from these conditions. Nevertheless, an understanding of the pathogenesis of this condition, as well as a means of alleviating the anemia when the chronic disorder persists, has remained elusive. Recently, major advances have occurred toward understanding the pathogenesis of the anemia of chronic disease and its treatment, and these advances are reviewed.
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PMID:Pathogenesis and treatment of the anemia of chronic disease. 817 30

High renal uptake on bone marrow scan with indium-111 chloride is often shown in patients with bone marrow abnormality. We evaluated the renal uptake on bone marrow scan in 27 cases with aplastic anemia, 20 cases with myelodysplastic syndrome (MDS) and 10 cases with other diseases. The high renal uptake was observed in patients not only with aplastic anemia but also with MDS. The renal uptake correlated with blood transfusion units, unsaturated iron binding capacity (UIBC), blood pool imaging and bone marrow uptake. The renal uptake correlated with UIBC better than with the blood transfusion units. Following mechanism of the renal uptake is proposed that frequent blood transfusion makes low UIBC, and the low UIBC causes the failure to chelate indium with transferrin. The fast blood clearance of un-chelated indium via kidneys is followed. Hypoplastic bone marrow may also play an important role for the high renal uptake because all patients with the high renal uptake could not be explained by above mentioned mechanisms. Caution should be paid to the scans with the high renal uptake because both aplastic anemia and MDS patients show the high renal uptake.
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PMID:[Evaluation of renal uptake on 111InCl3 bone marrow scintigraphy in patients with aplastic anemia and myelodysplastic syndrome]. 831 88

The red cell ferritin (rFt) level in 10 patients with refractory anemia (RA) was measured and analyzed by column isoelectric focusing (IEF). The levels in 9 of the 10 patients (90.0%) were higher than the upper limit in healthy controls (MV +/- SD: male 14.3 +/- 10.3 ag/cell, female 7.5 +/- 3.6 ag/cell). The isoelectric point (pI) of rFt determined by IEF in healthy subjects ranged from 5.1 to 5.7. However, the pI ranges for RA patients varied widely; the pI value was thought to correlate with the severity of the morphological abnormalities of bone marrow (BM) erythroblasts. That is, the greater the proportion of morphologically abnormal erythroblasts with respect to all erythroid precursors, the lower the pI range for rFt. The rFt content was not related to serum iron, transferrin saturation, serum ferritin, reticulocyte count, red cell iron content, or BM erythroblast count. These data suggest that rFt synthesis in RA patients is influenced by factor(s) other than iron; this is considered an essential feature of erythropoiesis in myelodysplastic syndrome (MDS).
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PMID:Quantitative and qualitative studies of red cell ferritin in refractory anemia of myelodysplastic syndrome. 834 42


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