Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0240066 (iron deficiency)
 7,156 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serum erythropoietin (S-EPO) levels were measured in 50 patients with anaemia of chronic disorders (ACD), classified into three groups according to their aetiology: inflammatory (n = 20), infectious (n = 15) and neoplastic (n = 15). The inflammatory group showed a higher mean S-EPO level (mean value +/- SEM, 69 +/- 11 mU ml-1) than the neoplastic (43 +/- 5 mU ml-1; P less than 0.05) and infectious groups (27 +/- 4 mU ml-1; P less than 0.01). The S-EPO level in the inflammatory group also differed from that of 32 healthy controls (36 +/- 3 mU ml-1; P less than 0.05). Fourteen patients with added iron deficiency (12 subjects from the inflammatory group) showed the highest S-EPO concentration (72 +/- 17 mU ml-1). Conversely, S-EPO levels were lower in febrile subjects (12 patients with infection and five with malignancy) than in non-febrile patients (28 +/- 4 mU ml-1 vs. 55 +/- 7 mU ml-1; P less than 0.01). In the infectious group, the logarithm of S-EPO correlated directly with the haemoglobin and haematocrit values. We conclude that differences in S-EPO concentration in ACD may be further related to the patient's iron stores and temperature. A decrease in EPO production may contribute to the pathogenesis of ACD secondary to infection.
 ...
PMID:Serum erythropoietin levels in the anaemia of chronic disorders. 199 63

Moderately increased blood levels of endogenous erythropoietin (Epo) usually induce complete restoration of renal anemia after successful kidney transplantation. With good graft function erythropoiesis is maintained by normal Epo serum levels. Persistent anemia can be related to iron deficiency, low excretory graft function, and high dosage of immunosuppressive agents leading to marrow suppression or nephrotoxicity. Acute early rejection is associated with a fall in serum Epo and abrogation of reticulocytosis. About 15% of recipients fail to exhibit the normal feedback regulation and develop a mostly transient posttransplant erythrocytosis. Both an increased sensitivity of erythrocytic progenitors to Epo and inappropriate Epo secretion by the native kidneys may account for this overshooting reaction.
 ...
PMID:Erythropoiesis and erythropoietin levels in renal transplant recipients. 202 70

We investigated the serum erythropoietin (Epo) response in 11 rheumatoid arthritis (RA) patients without anaemia, 7 with RA and iron deficiency (ID) and 12 with RA and anaemia of chronic disease (ACD). In all patients the serum Epo was higher than in healthy subjects. Apparently this increase was insufficient to prevent anaemia in ID and ACD. Serum Epo correlated negatively with serum ferritin. Ten RA patients with ACD were treated with the oral iron chelator 1,2-dimethyl-3-hydroxypyrid-4-one (L1). No obvious toxicity signs occurred after one week of treatment. It effectively released iron from iron stores. The Hb rise (in 70% of the patients) was correlated positively with an Epo increase and negatively with a serum ferritin decrease. We conclude that a serum Epo increase does not overcome ACD. Epo response might correlate inversely with iron stores. L1 treatment effectively chelates iron from iron stores. The effects of L1 on erythropoiesis and serum Epo and its safety need further substantiation after prolonged treatment in more RA patients.
 ...
PMID:Impaired erythropoietin responsiveness to the anaemia in rheumatoid arthritis. A possible inverse relationship with iron stores and effects of the oral iron chelator 1,2-dimethyl-3-hydroxypyrid-4-one. 205 65

After decreasing in the first trimester of pregnancy, the total red blood cell mass increases in the second and third trimesters to peak at term at about 120% to 125% of nonpregnant values, but how this is brought about by changes in the rate of erythropoiesis is not known. We evaluated erythropoiesis by measuring serum transferrin receptor (TfR) levels in 406 women during normal pregnancy (N = 317), at delivery (N = 63), or in the early postpartum (N = 27). Despite the presence of the placenta and the frequent occurrence of iron deficiency, TfR levels remained low in the first two trimesters and increased in the third trimester and at delivery. To explain why erythropoiesic activity was relatively low in early pregnancy, we also measured serum immunoreactive erythropoietin (Epo) in relation to the degree of anemia. There was a very strong correlation between serum TfR and Epo levels in the entire group (r = .59, P less than .0001) as well as in each period of pregnancy. Epo levels remained low for the degree of anemia and did not correlate with hematocrit in the first two trimesters, but recovered afterwards. In the early postpartum, Epo production and erythropoiesis were normal. We conclude that: (1) erythropoiesis is decreased in the first part of pregnancy but increases afterwards; and (2) blunted Epo production in early pregnancy could be responsible for that observation.
 ...
PMID:Blunted erythropoietin production and decreased erythropoiesis in early pregnancy. 173 97

The pathogenesis, diagnosis and treatment of the anaemia of chronic disorders (ACD) in rheumatoid arthritis (RA) were reviewed. Causes of anaemia other than ACD frequently present in RA. Decreased iron absorption was shown to be the result of active RA rather than a cause of ACD or iron deficiency. It has been hypothesized that bone marrow iron availability decreases due to decreased iron release by the mononuclear phagocyte system or that the anaemia in ACD is due to ineffective erythropoiesis; these remain controversial theories. Studies considering a decreased erythropoietin responsiveness have not produced consistent results. Erythroid colony growth is suppressed in vitro by interleukins and tumour necrosis factor but their role in vivo in ACD is unknown. The diagnosis of ACD is made by exclusion. Iron deficiency is detected by transferrin, ferritin, and cellular indices after adaptation of their normal values. Treatment of the anaemia consists merely of antirheumatic treatment. Iron administration is counterproductive since iron chelators or exogenous erythropoietin administration might increase erythropoiesis.
 ...
PMID:Anaemia in rheumatoid arthritis: pathogenesis, diagnosis and treatment. 218 49

Principal concepts concerning the anemia of RA are summarized in Tables 7 and 8. These concepts have been validated by our analysis of 93 anemic RA patients and by our review of the literature. The fact that anemia in RA may have one or more etiologies, occasionally in the same patient, mandates a reasoned approach to the analysis of anemia in every RA patient in whom it may occur. In particular, iron deficiency is common and determination of bone marrow iron content via an aspirate may be required for a definitive diagnosis. In those RA patients with anemia of chronic disease, the best therapy remains control of the underlying disease, most commonly with second line drugs and/or corticosteroids. The place for recombinant erythropoietin in the therapy of this anemia has not been defined; one specific role for erythropoietin may be in the preparation of RA patients for elective surgery, particularly hip arthroplasty, where correction of the anemia may either obviate the need for transfusion or may allow for donation of blood for purposes of autologous transfusion perioperatively. The pathogenesis of the anemia of chronic disease, as seen in RA anemia, is not completely understood. Inflammatory mediators, particularly the cytokines, appear to be important factors in the impairment of erythropoiesis. The mechanism by which these cytokines impair erythroid progenitor growth and hemoglobin production in developing erythrocytes is an important area for future study.
 ...
PMID:The pathogenesis of anemia in rheumatoid arthritis: a clinical and laboratory analysis. 218 69

A group of 50 patients (26 men and 24 women, mean age 50 +/- 19 years and range 21 to 67) on chronic hemodialysis (HD) and with basal levels of hemoglobin (Hb) less than or equal to 8 g/dl was treated with recombinant human erythropoietin (r-HuEpo) during 3 months. r-HuEpo was started at 50 U/kg I.V. 3 times a week, immediately after each session of HD, for 4 weeks, and this dose was increased in steps of 25 U/kg until a Hb level of 12 g/dl or a maximum dose of 100 U/kg were reached. Complete blood counts and biochemical profile were performed before the first dose of r-HuEpo and once weekly and monthly respectively during the period of treatment. In 8 patients the red-cell life span was studied with cromium 51 labelled erythrocytes just before and after treatment. One patient had a grand mal seizure and the r-HuEpo was discontinued. In 44 patients the mean hematocrit increased from 21.8% to 32.1% and in the other 5 there were no response because of iron deficiency. There were no changes in leucocytes and platelets counts and consistent decreases in iron and ferritin serum concentrations were observed despite oral supplementation of iron. In the 8 patients studied the shortened erythrocyte survival did not suffer any significant variation with r-HuEpo. Predialysis creatinine, urea and phosphorus blood levels increased significantly at 3th month of treatment but there was no increase in potassium. In 32.6% of previously normotensive and hypertensive patients an increase in blood pressure was founded. Thrombosis of arteriovenous fistulas and other severe clinical side effects were not observed.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:[Treatment of anemia in patients with chronic kidney insufficiency in hemodialysis with erythropoietin]. 222 Apr 24

The dose of recombinant human erythropoietin (r-HuEPO) required to correct the anemia of end-stage renal disease (ESRD) varies among patients. The response to r-HuEPO is impaired if absolute or relative iron deficiency exists. Aluminum may cause a microcytic anemia in patients with ESRD, but the mechanism remains incompletely defined. Twenty-two patients in the Canadian Multicentre EPO trial were studied for 6 months. In this randomized double-blind placebo-controlled trial, free erythrocyte protoporphyrin (FEP) was used as an indicator of iron-deficient deficient erythropoiesis. The relationship of FEP to the estimates of iron availability (serum iron, transferrin saturation, ferritin) and iron utilization (corrected reticulocyte count, hemoglobin) was evaluated by multiple linear regression analysis. The effect of aluminum on FEP was evaluated by adjusting the statistical model for this variable. All patients were iron replete as assessed by serum ferritin. FEP was not related to serum aluminum before administration of r-HuEPO, but it was significantly correlated with aluminum in the treated group. In hemodialysis patients treated with r-HuEPO, the proportion of the variability explained by the parameters of iron utilization and iron availability was 0.27. The effect of aluminum increased this to 0.59. In hemodialysis patients not receiving r-HuEPO, the proportion of variability in FEP explained by the model increased from 0.16 to 0.28 by adjusting for aluminum. The data support the hypothesis that aluminum interferes with the bioavailability of stored iron for erythropoiesis and thus may result in a microcytic anemia in patients with ESRD or may blunt their response to r-HuEPO therapy.
 ...
PMID:Bioavailability of iron in hemodialysis patients treated with erythropoietin: evidence for the inhibitory role of aluminum. 223 35

The quantitative variation among patients in their response to erythropoietin can be explained, in part, by factors that can independently cause anemia in patients with end-stage renal disease. Aluminum can blunt the effect of erythropoietin, in part by interfering with iron bioavailability. This inhibitory effect cannot be completely overcome by aggressive ferrotherapy, but can be reversed with aluminum chelation therapy. A patient is described who developed hematological evidence of aluminum excess after being treated with erythropoietin. The biochemical evidence of functional iron deficiency and the response to aluminum chelation therapy support the hypothesis that the inhibitory effect of aluminum on erythropoiesis is mediated by the interference of aluminum with the bioavailability of iron.
 ...
PMID:The role of aluminum in the functional iron deficiency of patients treated with erythropoietin: case report of clinical characteristics and response to treatment. 223 43

In order to clarify possible factors responsible for varying responses in uremic patients treated with recombinant human erythropoietin (rHuEPO), we determined the inhibitory effects of ten uremic sera on the erythroid progenitors (CFU-E) and erythroid bursts (BFU-E). We also measured plasma EPO titers, Fe, UIBC, ferritin, PTH-C, beta 2-microglobulin, and aluminum in all ten patients. The inhibitor of CFU-E but not BFU-E, was present in the serum of the single anemic patient whose recovery took longer after the administration of rHuEPO. He did not have such conditions as iron deficiency, excess of aluminum, or chronic inflammation. The remaining patients, who had no CFU-E or BFU-E inhibitors, were good responders to rHuEPO. In none of ten patients were there inhibitors of granulocyte-macrophage progenitors (CFU-GM) or any differences in the other parameters. Although the inhibitory factor of CFU-E can be overcome with a larger dose, its prior determination may be useful to set out minimal effective dose of EPO treatment.
 ...
PMID:The inhibitory factors of hematopoiesis in chronic hemodialysis patients treated with recombinant human erythropoietin. 224 92


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>