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Query: UMLS:C0240066 (iron deficiency)
 7,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The anemia of Belgrade b/b rats has been shown to be due to intracellular iron deficiency. The aim of this study of erythropoiesis at the progenitor cell level in these rats was to determine if a defect is present in the early phase of red cell production. Both erythroid colony-forming unit (CFU-E)- and erythroid burst-forming unit (BFU-E)-derived colonies were found to be few in untreated b/b rats and made up of a small number of poorly hemoglobinized erythroblasts of different size and irregular cell shape. Following treatment with iron, the anemia of the rats improved, and the number of CFU-E-derived colonies and the number of cells per colony increased, but the peculiar erythroblast morphology persisted. The high serum level of biologically active erythropoietin (Ep) in b/b rats rules out inadequate Ep production as a cause of their anemia. The results presented indicate, in addition to the earlier described defective transmembrane iron transport, a defect in erythroid progenitor cells. The effect of iron treatment in these rats detected in vitro on erythroid progenitors confirms the importance of iron for cellular proliferation.
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PMID:Erythroid progenitors in anemic Belgrade laboratory (b/b) rats. 275 90

Treatment with recombinant human erythropoietin (r-HuEPO; EPOGEN [epoetin alfa], AMGEN Inc, Thousand Oaks, CA) rapidly corrects the anemia associated with end-stage renal disease during the acute phase of therapy and supports hematocrit levels throughout the maintenance phase. However, during the acute phase of therapy, iron deficiency will develop in most patients; it is therefore initially essential to monitor body iron stores monthly. A plasma ferritin level of less than 30 ng/mL or a transferrin saturation level of less than 20% confirms the diagnosis of iron deficiency. Microcytic, hypochromic red cell morphology appears only after prolonged iron deficiency due to inadequate monitoring and insufficient iron supplementation; alternatively, microcytosis in the presence of adequate iron stores suggests aluminum toxicity. In all patients except those with transfusional iron overload, prophylactic supplementation with ferrous sulfate (325 mg up to three times daily) is recommended. When oral supplements, which are poorly tolerated at high doses, are insufficient to meet the extraordinary needs resulting from r-HuEPO-induced erythropoiesis, intravenous iron dextran (500 to 1,000 mg administered in five to ten doses) may be required. During the maintenance phase of therapy, it may be necessary to continue iron supplementation to counteract ongoing loss of iron associated with blood loss through dialyzers and gastrointestinal bleeding. At the other extreme of iron balance, iron overload in transfusion-dependent patients, recent studies suggest that the ability of r-HuEPO to mobilize iron stores can be harnessed with therapeutic phlebotomy to reverse transfusional iron overload.
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PMID:Iron management during recombinant human erythropoietin therapy. 275 26

To define the hematologic changes during a mild viral infection, 93 infants were immunized with live attenuated measles virus and studied prospectively at 0, 4, 9, 14, 21, and 30 days. Hemoglobin concentration decreased significantly by days 9 and 14. The decrease was greater than 1.0 g/dL in 8.6% and greater than 0.6 in 24.3% of the infants. Of the nonanemic infants, 22% became anemic. Serum iron and percentage saturation of transferrin decreased, whereas serum ferritin increased significantly. Mean cell volume, iron-binding capacity, protoporphyrin, and haptoglobin did not show changes. Reticulocyte index and erythropoietin increased significantly at 30 days. Leukocyte counts, Zetacrit, and C-reactive protein did not help to predict the hemoglobin decrease. These results suggest that a mild viral infection in infants induces a significant decrease in hemoglobin that may persist for 14 to 30 days and may be difficult to distinguish from iron deficiency.
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PMID:Anemia of a mild viral infection: the measles vaccine as a model. 279 79

The accurate radioimmunological measurement of serum erythropoietin (EPO) levels has only been possible since the development of highly specific antibodies directed against recombinant human EPO. In the present study, we determined the serum EPO levels in 100 healthy volunteers and in over 300 patients with anemias and hyperglobulinemia of various causes. In the healthy group, the females had levels of 11.3 +/- 3.4 mU/ml, while the males had levels of 8 +/- 3.2 mU/ml. The serum EPO concentrations were inversely related to the degree of anemia in patients with nonrenal anemias, while predialysis patients with renal anemias showed only partially such a tendency. Hemodialysis patients exhibited EPO-levels that were inadequately low relative to the degree of anemia. Patients with hyperglobulinemia had significantly higher serum EPO-levels than healthy individuals and polycythemia vera patients, the latter having particularly low serum EPO levels. Our results show that the determination of serum EPO levels can be of value in the differential diagnosis of hyperglobulinemia. Finally, sequential measurements document fluctuating serum EPO-levels after gastrointestinal hemorrhages and in patients with iron deficiency anemias receiving iron substitution. The probable reason for this phenomenon seems to be the intermittent utilisation of the hormone by EPO-sensitive erythropoietic precursor cells.
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PMID:[Serum erythropoietin levels in several diseases]. 291 82

The effect of repeated phlebotomy on serum immunoreactive erythropoietin levels was studied prospectively in 69 autologous blood donors. At the time of the initial phlebotomy, 11 men (33%) and two women (6%) were anemic; during the course of blood donations, anemia (defined as a hematocrit less than 0.41 for men and less than 0.36 for women) developed in an additional 17 men (71%) and 14 women (45%). Although there was an increase in the level of serum immunoreactive erythropoietin with successive phlebotomies, the increase was not substantially out of the normal range. The lack of an erythropoietic response to repeated phlebotomies in association with the small increment in the serum erythropoietin level was not due to iron deficiency, since the level of red-cell free protoporphyrin did not increase in these patients. We conclude that within the hematocrit range permissible for autologous blood donation, the degree of anemia experienced is insufficient to initiate an adequate increase in erythropoietin production; as a consequence, mild anemia develops in a majority of donors, and the volume of blood donated is inadequate to meet their operative needs.
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PMID:Effect of repeated whole blood donations on serum immunoreactive erythropoietin levels in autologous donors. 291 36

Effects of cadmium (Cd) on in vitro and in vivo erythropoiesis in rats were studied by methylcellulose colony assay. Cd suppressed the in vitro growth of late erythroid progenitors (CFU-E) in a dose-dependent fashion and did not lose its inhibitory potency with increasing doses of erythropoietin (EPO). In addition, in marrow suspension cultures, Cd did not significantly influence 59Fe incorporation into both the cells and heme, and the Cd dose-responsive inhibition curve of the number of living cells was similar to that of CFU-E. These results suggest that the suppression of CFU-E colony formation by Cd is not due to the blocking of either EPO action to stimulate the growth of CFU-E or the iron incorporation into the cells ahd heme, but due to its direct cytotoxic effect. The colony suppression by Cd could be prevented by adding metallothionein to the cultures. On the other hand, oral administration of Cd to animals (100 mg/liter in drinking water) induced an iron deficiency anemia characterized by microcytic hypochromic red cells, decreased plasma iron, and increased total iron binding capacity. Marrow CFU-E density steadily increased as plasma iron decreased due to Cd administration and reached a plateau after 50 days. Plasma EPO titers were also found to be elevated in such a Cd-induced anemia. Parenteral iron administration during the Cd drinking period could completely prevent the development of iron deficiency anemia and the increase of both CFU-E and plasma EPO. There was a hyperbolic correlation between CFU-E and plasma iron or transferrin saturation. These results demonstrate that oral CD administration produces bone marrow hyperplasia at the CFU-E level due to iron deficiency.
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PMID:Effects of cadmium on in vitro and in vivo erythropoiesis: erythroid progenitor cells (CFU-E), iron, and erythropoietin in cadmium-induced iron deficiency anemia. 339 Dec 51

The serum level of erythropoietin was measured in 31 patients with anemia secondary to chronic infection or malignancy and compared with erythropoietin levels in 23 patients with iron-deficiency anemia and 14 patients with primary hematopoietic diseases. Erythropoietin levels varied directly with the degree of anemia in patients with iron deficiency or primary hematopoietic disorders. There was no correlation of erythropoietin and the degree of anemia in patients with chronic infection or malignancy and the erythropoietin levels were significantly lower than in patients with iron deficiency or primary hematopoietic disease and the same degree of anemia. A major factor in the anemia of chronic disorders is a decrease in levels of erythropoietin.
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PMID:Serum level of erythropoietin in anemias associated with chronic infection, malignancy, and primary hematopoietic disease. 510 67

In the bone-marrow, non-haemoglobin iron can predominantly be found in the reticulum. Slight granules containing iron can also be observed in parts of erythroblasts by means of the Berlin blue reaction. These cells are called sideroblasts. In chemical respect, non-haemoglobin iron consists of ferritin soluble in water and haemosiderin insoluble in water. Erythroblasts will only take their iron from plasma transferrin. For the most part, this iron uptake is being regulated by erythropoietin adapting erythropoiesis to the oxygen requirements of the tissue. The iron contained in erythroblasts is predominantly utilized for haemoglobin synthesis in these cells. A slight part is being taken up by ferritin. The bone-marrow reticulum will phagocytise aged erythrocytes and store liberated iron as ferritin and haemosiderin. Part of the iron is being delivered again to plasma transferrin. With constant serum iron level the liberation of iron from the reticulo-endothelial tissue must correspond to the iron uptake by erythropoiesis. The absence of iron capable of being coloured in the bone-marrow reticulum is considered to be a reliable parameter of iron deficiency. It enables the diagnosis of iron deficiency anaemia to be made even in those patients with serum iron level and a total iron binding capacity lying within the normal range and no hypochromia of erythrocytes being present. It enables iron deficiency anaemia to be separated from sideropenic anaemia with reticulo-endothelial siderosis in differential-diagnostic manner. Even in patients with sideroblastic anaemia, iron colouring of bone-marrow smears is required for ensuring the diagnosis. Recently, a separation has also been made for idiopathic anaemia with abnormal sideroblasts. In these patients there is an increased risk for acute leukemia to develop.
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PMID:[Iron in bone marrow]. 618 56

Over the first three months of continuous ambulatory peritoneal dialysis (CAPD) the level of hemoglobin (Hb) rises significantly in most patients. To elucidate this further we studied the hematological response over 3 months of 8, previously non-transfused new patients treated with CAPD. Mean Hb rose by +2.78 g/dl (P less than 0.02). Mean RCM rose by 284 ml (37.7%) (P less than 0.05) and 3.7 ml/kg (29.6%) (P less than 0.05). PV fell relative to BW only, by -8.6 ml/kg (P less than 0.05). There was no significant change in serum vitamin B12 or folate concentrations or evidence of hemolysis. Plasma ferritin fell in all patients, but hematological changes of iron deficiency appeared in only one. Bio-assayable erythropoietin (EPO) levels were generally in the normal range, but inappropriately low for the degree of anemia. EPO did not change significantly apart from in two patients, one with polycystic disease. These results indicate that over the initial 3 months of therapy the majority of CAPD patients have a rise in Hb, due mainly to a rise in RCM, unrelated to changes in serum EPO level.
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PMID:The hematological response to continuous ambulatory peritoneal dialysis. 647 59

A mesenteric mass, histologically characterized as giant lymph node hyperplasia was found in an 18-yr-old man with at least 11 yr of growth retardation and anemia. The anemia was characterized by iron deficiency from selective malabsorption of iron, and by features of the anemia of chronic disorders. In contrast with a previous report, no inhibitor of erythropoietin was found and there was no abnormality of erythropoietin secretion. Resection of the mass was followed by rapid correction of the anemia and catch-up growth. The mass had histologic features of the hyaline vascular and plasma cell types of Castleman's disease with multinucleate giant cells probably of macrophage origin. Immunologic studies of the mass showed that the B lymphocytes were polyclonal and the T lymphocyte helper/suppressor cell ratio was normal, suggesting that giant lymph node hyperplasia is a local inflammatory reaction.
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PMID:Giant lymph node hyperplasia (Castleman's disease) of the mesentery. Observations on the associated anemia. 672 65


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