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

A high RBC count combined with a low mean volume generally is attributed to thalassemia minor, either alpha or beta, or to polycythemia vera with iron deficiency. Among 330 patients with a mean corpuscular volume (MCV) less than 70 cumu, 35 had increased RBC counts. Of these, 26 had thalassemia minor and four had polycythemia vera. Five had secondary polycythemia (four from hypoxia, one from hypernephroma) with incidental iron deficiency. In the four of these patients given iron, the RBC count remained above normal and the MCV rose to normal. The RBC size distribution curves reliably distinguished between thalassemia minor and polycythemia with iron deficiency.
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PMID:Microcytic polycythemia. Frequency of nonthalassemic causes. 57 67

The onset of postpolycythemic myeoloid metaplasia or spent polycythemia has been recognized for many years. As the result of many different series, the development of postpolycythemic myeolid metaplasia might be expected in from 15%-20% of patients with postpolycythemia vera. It appears that an etiologic role for sodium phosphate 32P may exist in this evolutionary pattern. About 70% of patients with PPMM will have symptoms with the onset of the syndrome. The major mechanisms producing symptoms result from (1) anemia, (2) pressure from massive splenomegaly, and (3) bleeding problems. Iron deficiency is a frequent cause of anemia in patients with PPMM. The major mechanism of anemia in these patients, however, relates to ineffective erythropoiesis and shortened red cell survival. Androgen trials for ineffective erythropoiesis seem worthwhile, although data on this point is too limited to draw any firm conclusions. A steroid trial for those patients with major hemolytic episodes is indicated. In those patients in whom adrenal steroid therapy fails to control major hemolysis, a consideration for splenectomy exists. Pressure-related manifestations secondary to massive splenomegaly have been treated with radiation therapy and oral alkylators. Although there is data to document amelioration of painful symptoms with associated shrinking of the spleen, long-term control of this problem has not been forthcoming. Again, patients who are medical failures in control of pressure-related manifestations may be considered for splenectomy. Bleeding problems may arise with PPMM secondary to thrombocytopenia, thrombocythemia, or qualitative platelet dysfunction. Adrenal steroids have met with some success in improving platelet counts in patients with life-threatening thrombocytopenia. Those patients who are medical failures with adrenal steroids in terms of thrombocytopenia might be candidates for splenectomy. Control of thrombocythemia has been observed with oral alkylator therapy and chlorambucil may have a special role in managing this complication. Qualitative platelet defects leading to severe bleeding are best managed with fresh platelet transfusions. Patients with PPMM in contrast to patients with agnogenic myeoloid metaplasia have a more lethal syndrome and shortened survivorship. Causes of death in patients with PPMM include cardiac problems, transition to acute leukemia, hemorrhage, and infection.
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PMID:The evolution into and the treatment of late stage polycythemia vera. 125 Dec 24

Infants of diabetic mothers frequently have polycythemia, elevated serum erythropoietin concentrations, and decreased serum iron and ferritin concentrations, likely representing a redistribution of fetal iron into erythrocytes to support augmented fetal hemoglobin synthesis. We hypothesized that fetal liver, heart, and brain iron concentrations are also reduced in these infants. After obtaining autopsy tissue from infants who had died before 7 days of age, we measured liver, heart, and brain iron concentrations using atomic absorption spectrophotometry. Seven infants of diabetic mothers and seven gestational age-matched control infants were studied. All infants of diabetic mothers had pancreatic islet cell hyperplasia, indicating fetal hyperglycemia and hyperinsulinemia. Liver iron concentrations in the infants of diabetic mothers were 6.6% of control values (489.0 +/- 154.4 vs 7379.7 +/- 1473.8 micrograms/gm dry tissue weight (mean +/- SEM); p less than 0.001), heart iron concentrations were 43.9% of control values (124.7 +/- 20.5 vs 284.1 +/- 34.8 micrograms/gm dry tissue weight; p less than 0.002), and brain iron concentrations were 60.6% of control values (106.1 +/- 13.7 vs 175.2 +/- 10.7 micrograms/gm dry tissue weight; p less than 0.003). Heart and brain iron concentrations were directly correlated with liver iron concentrations (r = 0.80 for both; p less than 0.001) and indicated that hepatic iron was greater than 75% depleted before heart and brain iron reduction. We conclude that severely affected infants of diabetic mothers have reduced liver, heart, and brain iron concentrations. The role of tissue iron deficiency in the genesis of the abnormal clinical findings in these infants deserves further consideration.
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PMID:Iron deficiency of liver, heart, and brain in newborn infants of diabetic mothers. 162 67

We measured the complete blood cell count, including the index of RBC size heterogeneity (RBC distribution width [RDW]), in 181 subjects without anemia to determine whether RDW became abnormal earlier in the development of iron deficiency than did other variables. In 163 subjects selected only for otherwise normal blood cell counts, an increased RDW was 66% specific (48/73) and 100% sensitive (48/48) for decreased serum iron saturation. Stool guaiac testing was equally specific but less sensitive. In 13 subjects with polycythemia, as iron deficiency developed, RDW increased a minimum of four weeks before mean cell volume changed. In one apparently normal young woman, an abrupt isolated rise in RDW revealed a newly developed low serum transferrin saturation; all values remained normal during serial testing of four other normal subjects. We conclude that RDW is the part of the routine blood cell count that first becomes abnormal during the development of iron deficiency.
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PMID:Improved detection of early iron deficiency in nonanemic subjects. 396 26

Significant alterations in hemotologic function in cystic fibrosis are suggested by the observation that polycythemia is uncommon, even among cyanotic patients. To elucidate those factors that influence hematologic equilibrium, 39 stable patients with cystic fibrosis were evaluated with regard to hemoglobin, hematocrit, RBC indices, reticulocyte count, serum iron and total iron binding capacity, serum ferritin, vitamin E, and carboxyhemoglobin levels. Hemoglobin concentrations were below the 50th percentile for age in 90% of the patients, including the 23% who were cyanotic. Serum ferritin levels were below the mean for age in 85% and below 12 ng/mL in 33% of patients. Vitamin E levels were less than 5 micrograms/dL in 33%, indicating deficiency. Carboxyhemoglobin values were elevated in 64% of the patients. These data indicate that relative anemia is common in cystic fibrosis and suggest that iron and vitamin E deficiency may contribute to that anemia. Twenty-two patients with cystic fibrosis were then given 2 weeks of oral iron therapy followed by two to three additional weeks of iron and vitamin E. This therapeutic trial resulted in an increase in mean hemoglobin concentration from 13.87 to 14.50 g/dL (P less than 0.01) associated with a significant increase in levels of serum ferritin (P less than 0.001). The increase in hemoglobin occurred primarily during the second 2 weeks when patients were receiving both iron and vitamin E. However, we were unable to document evidence of increased hemolysis when patients were receiving iron therapy alone. This response to oral iron therapy is confirmation that iron deficiency contributes to the failure of some patients with cystic fibrosis to compensate hemotologically for hypoxia.
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PMID:Relative anemia and iron deficiency in cystic fibrosis. 683 67

Patients with chronic hypoxia develop a physiologically appropriate "secondary" polycythemia that improves oxygen carrying capacity. Supplemental iron is often required to maintain this. In severe cases when hematocrit levels approach 70%, iron is withheld in order to avoid dangerously high hematocrit levels and the risks of vascular sludging due to "hyperviscosity." Some patients even require reduction of viscosity by exchange of their polycythemic blood for plasma when symptoms develop. Iron deficiency with microcytic polycythemia can then develop. Management of such patients is unclear. Continued blood withdrawal will worsen the iron deficiency; iron supplementation will increase the hematocrit level and the risks of hyperviscosity. The combination of frequent phlebotomy with oral iron therapy should improve iron stores while safely maintaining a stable hematocrit level in patients with microcytic polycythemia. This combination should also have multiple beneficial effects on tissue oxygen delivery and utilization. This approach has been discussed and used for a patient with microcytic polycythemia due to Eisenmenger syndrome. While on therapy the patient's clinical symptoms decreased, and his serum iron level, hematologic indices, and treadmill tolerance tests all improved.
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PMID:Phlebotomy with iron therapy to correct the microcytic polycythemia of chronic hypoxia. 725 95

Anemia does not correct in many kidney transplant recipients, probably due to iron deficiency or inadequate erythropoietin (Epo) production. We evaluated effects of iron (Fe) availability on correction of anemia in renal transplant recipients and sought to characterize patterns of early Epo production by transplanted kidneys as related to peritransplant factors. In a prospective randomized trial, 51 consecutive renal transplant patients were followed for 6 months. Epo was measured on days 0, 3, 14, 48 and 168 posttransplantation. Fe status was monitored on days 14, 48 and 168. Pts were randomized at day 14 based on Fe status. Iron-deficient (FeD) patients (n = 24) were randomized to receive daily Fe supplementation (FeDs, n = 12) or no supplementation (FeDns, n = 12). Those with normal Fe status (FeN, n = 27) were followed as controls. No differences were found between groups at day 0 for Hct, Cr, Epo, age, dialysis history, or type of donor. Day 3 Creatinine and Hct were similar among groups, while Epo was significantly higher in FeD groups vs FeN (p < 0.004), and continued higher at 6 months. Though each pt improved Hct, most FeDns and FeN were anemic and Fe deficient at 6 months while all FeDs patients had corrected their anemia (p < or = 0.009) and Fe status. Four FeDs patients developed polycythemia. Epo production correlated inversely to cold ischemia time in cadaver renal allografts (p < 0.008).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Factors affecting erythropoietin production and correction of anemia in kidney transplant recipients. 794 39

We evaluated the quantitative value of a simple model of erythropoiesis, based on the basic assumptions that the red blood cell (RBC) mass determines erythropoietin (Epo) production, which in turn stimulates erythropoietic activity. The RBC mass was quantitated by direct isotopic measurement (RCM), Epo production by serum Epo levels, and erythropoiesis by the ferrokinetic measurement of the erythron transferrin uptake (ETU), the serum transferrin receptor (TfR) level, and the reticulocyte (retic) index, and was completed by an evaluation of overall marrow erythron cellularity. We studied a total of 195 subjects, including 31 normal individuals, 38 patients with polycythemia, and 126 patients with various forms of anemia. Instead of only quantitating Epo and erythropoiesis in absolute terms, we also evaluated them in relation to the degree of anemia or polycythemia, and expressed the results as a ratio of observed values to values predicted from the regression equations between hematocrit (Hct) on the one hand, and Epo, TfR, and ETU on the other, obtained in a carefully selected subpopulation. The slope of the regression of TfR (as well as ETU) versus Hct was very similar to the slope of the regression of Epo versus Hct. Average EPO and TfR (as well as ETU) values predicted from the regression equations were quite comparable to observed values in most groups of subjects, with exceptions predictable from knowledge of the pathophysiology of these hematologic disorders. We identified four major patterns of erythropoiesis, ie, normal, hyperdestruction (with variants of hemolysis or ineffective erythropoiesis), intrinsic marrow hypoproliferation, and defective Epo production. Dissecting out groups of patients showed much greater heterogeneity than when patients were analyzed by group. This was particularly true in the case of a hypoproliferative component being combined with hyperdestruction, giving what we called a "mixed disorder of erythropoiesis." We conclude that the pathophysiology of anemia can be assessed by a simple measurement of Hct, retic index, Epo, and TfR levels, with Epo and TfR being more informative when expressed in relation to the degree of anemia. The model is particularly useful for detecting the presence of multiple mechanisms of anemia in the same patient. However, it has limitations inherent to the relative invalidity of TfR in iron deficiency, the imprecision of a retic count, and the difficulty in distinguishing hemolysis from ineffective erythropoiesis in some patients and in recognizing a component of hyperdestruction in hypoproliferative anemia.
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PMID:Quantitative assessment of erythropoiesis and functional classification of anemia based on measurements of serum transferrin receptor and erythropoietin. 842 88

Concentration of malonic dialdehyde (MDA) and activity of antioxidant enzymes G-6-PD, glutation peroxidase (GP), glutation reductase, catalase, superoxide dismutase were measured in red cells of patients with polycythemia vera. Plasmic ions Fe3+ were estimated by means of electron-paramagnetic resonance. MDA concentration and antioxidant enzymes (except GP) in polycythemia red cells were found increased, while the activity of selenium-dependent GP was reduced, the inhibition being greatest in severe iron deficiency. It is suggested that GP activity in red cells depends on both selenium levels in the body and concentrations of non-hematic iron.
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PMID:[Erythremia: the activity of erythrocyte antioxidant enzymes and the association with iron deficiency]. 921 64

We measured serum transferrin receptor (sTfR) levels in 22 patients with polycythemia vera and in 26 cases of secondary polycythemia. In our study, raised sTfR levels in both polycythemia groups were related to iron deficiency.
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PMID:Serum transferrin receptor in polycythemia. 983 Aug 13


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