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

In patients with idiopathic aplastic anaemia (n = 34) and Fanconi's anaemia (n = 8), sampled once or on several occasions, serum erythropoietin (Epo) increased with increasing severity of anaemia with apparently similar rates of increase in each group. However, after adjustment for Hb, log Epo values for the Fanconi's anaemics tended to be greater than those for the idiopathic aplastic anaemics (P < 0.01). Erythropoietin concentrations in serum samples from patients with Fanconi's and idiopathic aplastic anaemias tended to be greater than in samples from patients with anaemias from protein energy malnutrition, myelodysplasia and iron deficiency. The results suggest that there is no deficiency of erythropoietin in Fanconi's and idiopathic aplastic anaemias and that if exogenous erythropoietin is of any benefit it would need to be administered in doses large enough to induce a significant increase in log Epo. Results of the study illustrate the need to take account of the assumptions which underlie interpretation of the statistical analysis. Use of erythropoietin values in place of log Epo gives misleading conclusions demonstrable as invalid as the conditions for normality of distribution of the data and homogeneity of variances were not satisfied.
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PMID:Serum immunoreactive erythropoietin in patients with idiopathic aplastic and Fanconi's anaemias. 148 41

Erythrocyte ferritin may be a better estimator of iron bioavailability than the conventional markers of iron stores (serum ferritin and transferrin saturation). To investigate the accuracy of these conventional markers in uremic patients compared with erythrocyte ferritin, we studied 29 chronic hemodialysis patients on erythropoietin (EPO) therapy, 18 without EPO therapy, and 22 healthy control subjects. Apart from the red blood cell indices, serum ferritin, transferrin saturation, and erythrocyte ferritin, the analytical study included red blood cell protoporphyrin and plasma aluminum levels. The control group showed erythrocyte ferritin concentrations between 8.3 and 12.5 attograms/cell (95% confidence interval). In the EPO group, red blood cell protoporphyrin correlated negatively with erythrocyte ferritin, but not with serum ferritin or transferrin saturation. In the non-EPO group, serum ferritin, erythrocyte ferritin, and transferrin saturation did not correlate with red blood cell protoporphyrin. Even though erythrocyte ferritin correlated well with serum ferritin in the EPO group (r = 0.61, P = 0.0003), the sensitivity of normal serum ferritin levels (30 to 300 ng/mL) to discard a low erythrocyte ferritin concentration (erythrocyte ferritin less than 7 ag/cell) was 0.53, while the sensitivity of serum ferritin at levels less than 30 ng/mL to indicate an absolute iron deficiency expressed as a low erythrocyte ferritin concentration was 0.28. Only values of serum ferritin and transferrin saturation greater than 300 ng/mL and 35%, respectively, could rule out a relative iron deficiency expressed as a low erythrocyte ferritin and high red blood cell protoporphyrin concentration. Plasma aluminum levels did not correlate with red blood cell protoporphyrin or erythrocyte ferritin levels in either uremic group.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Assessment of iron status by erythrocyte ferritin in uremic patients with or without recombinant human erythropoietin therapy. 151 5

We studied the significance of free erythrocyte protoporphyrin (FEP) in relation to iron status, aluminum levels and anemia in uremic patients on chronic dialysis. All but 1 patient showed high FEP values closely related to the degree of anemia. Increased FEP levels are due to a defective heme synthesis, not related to iron deficiency or aluminum overload. Treatment of anemia with recombinant human erythropoietin reduced FEP values. We therefore hypothesize that recombinant human erythropoietin ameliorates an enzymatic defect in heme synthesis.
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PMID:Recombinant human erythropoietin reduces free erythrocyte protoporphyrin levels in patients on chronic dialysis. 152 41

Eleven anemic children and adolescents with a median age of 14 years (range six months-20 years) on chronic hemodialysis were treated with recombinant human erythropoietin (rHuEPO) intravenously three times a week for an average of 9.2 months. After eight weeks of therapy, hematocrit rose from 20.3 +/- 1.4% to 31.7 +/- 0.7% (0.20 +/- 0.01 to 0.31 +/- 0.007, p less than 0.001, mean +/- SEM). After reaching the target hematocrit of 30% to 33% (0.30 to 0.33), doses were adjusted individually. Blood transfusions were eliminated in all but one patient. All patients experienced an increase in appetite and energy level. Serum ferritin concentrations decreased in all patients who reached target hematocrit and seven required iron supplementation. Hypertension worsened in two patients and developed in two others. One patient's vascular access clotted. Dialysis efficiency and heparin requirements during dialysis did not change significantly. We conclude that rHuEPO is safe, effective, and should be recommended as treatment for anemia in children and adolescents on hemodialysis, but close monitoring for the development of hypertension and/or iron deficiency is necessary.
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PMID:Therapy of renal anemia in children and adolescents with recombinant human erythropoietin (rHuEPO). 154 82

To assess the effects of decreased erythrocyte production on the levels of serum erythropoietin in children, we measured simultaneous hemoglobin concentrations and erythropoietin in 18 children with iron deficiency anemia, 17 children with transient erythroblastopenia of childhood (TEC), and 7 children with aplastic anemia. In all but two patients (one with TEC; one with aplastic anemia), erythropoietin was measured at diagnosis, before institution of specific therapy for the anemia. There was a statistically significant inverse linear correlation between log10 erythropoietin and hemoglobin values for all patient groups (r = 0.904 to 0.912; p less than 0.005). A comparison of the slopes of the regressions for each patient group by analysis of covariance revealed a significantly steeper slope for the iron deficiency group (-0.553) versus the TEC (-0.287) and aplastic anemia (-0.256) groups (p = 0.0001). The difference in erythropoietin levels appeared greatest in patients whose presenting hemoglobin level was greater than 5 gm/dl. Decline in serum erythropoietin levels was more precipitous in the less severely anemic patients with iron deficiency anemia than in the patients with TEC or aplastic anemia. These data reveal quantitative and qualitative differences in the relationship between serum erythropoietin and hemoglobin levels when children with severe iron deficiency anemia versus those with TEC or aplastic anemia are considered, even though all three conditions are characterized by hypoproliferation of erythrocytes.
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PMID:Comparison of the erythropoietin response in children with aplastic anemia, transient erythroblastopenia, and iron deficiency. 155 89

Advanced cancer is often accompanied by anaemia, which may worsen with concomitant administration of chemotherapy. Serum erythropoietin (EPO) concentrations are lower in cancer patients than in patients with iron deficiency, suggesting that the anaemia observed in cancer patients is at least partially due to a relative deficiency of EPO. Consequently, we studied the effects of recombinant human erythropoietin (r-HuEPO) therapy in three populations of anaemic cancer patients: patients not receiving concomitant chemotherapy or radiotherapy; patients receiving cyclic, non-cisplatin-containing chemotherapy, and patients receiving cyclic cisplatin-containing chemotherapy. Therapy with r-HuEPO was well tolerated; it increased haematocrit levels and corrected anaemia, irrespective of concomitant chemotherapy or the type of chemotherapy administered. A dose of 150 U/kg r-HuEPO given subcutaneously 3 times weekly decreased transfusion requirements after the 1st month of therapy; improved functional capacity was noted in patients who achieved a significant increase in haematocrit in response to r-HuEPO therapy.
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PMID:Recombinant human erythropoietin in the treatment of the anaemia of cancer. 157 66

ACD is probably the most common anemia among hospitalized medical patients. It is variably defined by its clinical and, particularly, its laboratory manifestations. The most consistent features are low serum iron and normal or increased serum ferritin levels, reflecting normal or increased iron stores and distinguishing ACD from iron deficiency anemia. ACD often coexists with iron deficiency and the anemia of renal insufficiency. Most patients have an underlying infectious, inflammatory, or neoplastic disease, but as many as one quarter of patients do not. Several mechanisms have been proposed, the most significant of which are a block in reutilization of hemoglobin iron for red cell production and relative deficiency of erythropoietin, but the pathogenesis and mediators involved remain uncertain. The anemia itself seldom requires treatment and is ameliorated by successful treatment of the underlying disease.
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PMID:Anemia of chronic disease. 157 57

Chronic renal failure is almost invariably accompanied by symptomatic anemia. It has been demonstrated that the primary cause of this anemia is inadequate production of erythropoietin by the diseased kidneys. The isolation of erythropoietin, followed by the cloning and expression of the human erythropoietin gene, made possible clinical trials of rHuEPO in uremic patients. rHuEPO produced dramatic increases in the hematocrit in almost all patients treated and also ameliorated many symptoms, such as lethargy, dizziness, and poor appetite, that had long been attributed to the effect of uremic toxins. Adverse effects of treatment with rHuEPO noted in the early clinical trials included hypertension, seizures, arteriovenous fistula or shunt thrombosis, and hyperkalemia. Further study of rHuEPO has shown that many of these side effects may be no more frequent in patients receiving rHuEPO than in other uremic patients not receiving rHuEPO. Reduction of the rHuEPO dosage and subcutaneous administration produce less rapid increases in the hematocrit and may lessen the incidence and severity of these side effects. rHuEPO therapy places great demands on both the body's iron stores and the capacity to rapidly transfer iron from storage sites to the erythroid progenitor cells. Thus, almost all patients treated with rHuEPO become iron deficient and require oral or parenteral iron replacement. Response to rHuEPO in uremic patients is diminished if the anemia is complicated by iron deficiency, inflammatory disorders, aluminum overload, or deficiency of folate or vitamin B12. rHuEPO therapy is safe and effective in the treatment of the anemia of chronic renal failure. The use of rHuEPO leads to enhanced quality of life and eliminates the need for red cell transfusions. In addition to hemodialysis patients, predialysis patients and those on CAPD benefit from and are candidates for rHuEPO therapy.
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PMID:Anemia of renal failure. Use of erythropoietin. 157 66

Newborn infants of diabetic mothers have serum biochemical signs of iron deficiency in cord blood directly related to elevations of cord erythropoietin and Hb concentrations. In sheep, chronic fetal hyperinsulinemia results in fetal hypoxemia, expansion of the red cell mass, and decreased iron concentrations, most likely due to increased iron utilization for Hb synthesis. To determine whether fetal insulin exposure also results in reduced tissue iron concentrations, we measured liver, skeletal muscle, small intestine, heart, and brain iron concentrations in newborn rat pups after s.c. fetal injection of insulin or diluent alone on d 19 of gestation. The fetuses of 11 pregnant rats were exteriorized, injected with 2 U neutral protamine Hagedorn insulin or diluent, replaced in utero, and delivered on d 22. To determine dose dependency, the fetuses of six pregnant rats were injected with 3 U of longer-acting protamine zinc insulin and delivered on d 21. At delivery, the insulin-treated groups had higher birth weights than the placebo-treated group, although plasma insulin concentrations were not different. The 2 U neutral protamine Hagedorn insulin-treated fetuses had significantly lower mean +/- SEM liver iron concentrations than the control fetuses (910 +/- 34 versus 1014 +/- 43 micrograms/g dry tissue weight; p less than 0.05), but had similar skeletal muscle iron concentrations. The 3 U protamine zinc insulin-treated fetuses had significantly lower liver and skeletal muscle iron concentrations compared to control and to 2 U neutral protamine Hagedorn insulin-treated fetuses (p less than 0.05). No differences in small intestine, heart, or brain iron concentrations were seen among groups.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:The effect of in utero insulin exposure on tissue iron status in fetal rats. 159 33

Anaemia in rheumatoid arthritis (RA) is a common and debilitating complication. The most common causes of this anaemia are iron deficiency and anaemia of chronic disease. Investigations have suggested that interleukin 1 (IL-1) or tumour necrosis factor (TNF), or both, from monocytes associated with chronic inflammation are responsible for the anaemia of chronic disease. On bone marrow examination anaemia of chronic disease is characterised by the diversion of iron from the erythropoietic compartment into marrow macrophages. This phenomenon is termed failure of iron utilisation. In this study, CFU-E (colony forming unit erythroid; late red cell precursors) and BFU-E (burst forming unit erythroid; early red cell precursors) stem cells were cultured from 10 normal marrow samples and 12 marrow samples from patients with RA with iron deficiency anaemia and 10 samples from patients with RA with failure of iron utilisation. All patients with RA were anaemic (haemoglobin less than 100 g/l), Potential accessory or inhibitory cells of erythropoiesis (CD4, CD8, or CD14 positive cells) were removed before culture. Control marrow samples were studied in a similar manner. Normal marrow samples yielded 377 (17) CFU-E and 133 (6) BFU-E (mean (SD)) colonies for each 2 x 10(5) light density cells plated. CD4 ablation caused reductions of 62 and 100% in CFU-E and BFU-E colonies respectively. CD14 removal resulted in considerable but lesser reductions of 46% for CFU-E and 25% for BFU-E. In both groups of patients with RA, CFU-E colony numbers were significantly lower than those seen in normal control subjects, 293 (17) for patients with iron deficiency anaemia and 242 (35) for patients with failure of iron utilisation. BFU-E colony numbers were 102 (13) and 108 (20) respectively. In patients with RA, CD4 removal caused a significantly greater loss of CFU-E colonies compared with normal control subjects. Cytolysis of CD14 positive cells caused a reduction in CFU-E colonies in the two RA groups which was similar to that seen in normal subjects. In conclusion, patients with RA seem to have fewer CFU-E progenitors but essentially normal numbers of BFU-E stem cells. Our data suggest a stimulatory role for marrow CD4 and CD14 cells in erythropoiesis in patients with RA. Monocytes-macrophages (CD14 positive) are known to be producers of IL-1 or TNF, or both, however, the predicted increase in the CFU-E colonies on removal of CD14 cells is not seen. Therefore, if IL-1 or TNF, or both, are responsible for the impairment of erythropoiesis in patients with RA, marrow macrophages are unlikely to be the source. Moreover, these results indicate the probability of erythropoietin resistance on the basis of diminished CFU-E colony formation in patients with RA.
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PMID:Anaemia of chronic disease in rheumatoid arthritis: effect of the blunted response to erythropoietin and of interleukin 1 production by marrow macrophages. 161 58


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