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

The authors describe an 18 year old athlete, a carrier of Hasharon haemoglobinopathy, pathology which had been checked in some ascendants too. Such a haemoglobinopathy, which has at first been verified in Ashkenazy Hebrew people and is nowadays rather common in North East Italy, shows clinical and laboratory features which are slightly or not at all mentioned in the literature. The leading reference point in the disease's development is the connection between splenomegaly and repetitive low erythrocytosis with serum iron deficiency and increase of the reticulocyte number. The same laboratory data had been observed in his father and in his paternal grandmother; both of them proved to te heterozygous carriers of Hasharon haemoglobinopathy. In all cases we caught the diagnostic validation by the means of isoelectrophoresis involving haemoglobin lysate in polyacrylamide gel. The authors think that the Hasharon shape they verified may be a variant of the classic phenotype: the splenomegaly and erythrocytosis may signify a brisk and primitive erythropoiesis with increasing reticulocytes, which might compensate for the anomalous synthesis of the alpha chains. Serum iron deficiency may signify an increase of the iron consumption. Moreover, the authors do not exclude the possibility of further associational abnormalities.
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PMID:[Hasharon hemoglobinopathy in a family]. 780 84

We calibrated the erythron transferrin uptake (ETU) and efficiency ratio (R-Ef) in erythropoiesis on the basis of ferroerythrokinetic data in 90 patients with iron deficiency anemia (IDA) and 64 patients with noncirrhotic and cirrhotic portal hypertension with splenomegaly (PH). Then we analyzed the data to elucidate how iron deficiency (ID) status effects variation of these values. ETU was significantly higher and R-Ef was lower in IDA subgroup before treatment (n = 71) than those with any recent treatment (n = 19), and in PH with anemia of ID type (PH-ID n = 39) than those without ID state (n = 34). A remarkable inverse correlation was obtained between ETU and R-Ef in both IDA and PH-ID and iron replacement therapy effected synchronous improvement of these values. We deduced the quantitative parameter of ID status (ID-x) on blood chemistry data in IDA by multiple regression of ETU and of R-Ef respectively. These calibration formulae were extrapolated to the data in PH-ID. Thus we delineate the factor which represents ID status in common to these two diseases to increase ETU and decrease R-Ef, although the contribution of ID-x was greater in IDA than PH-ID. Additional factors to enhance or modify these values were shortened survival of erythrocytes, splenomegaly and hepatic dysfunction.
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PMID:[Increased erythron transferrin uptake associated with ineffective erythropoiesis in iron deficiency state--the common factors to iron deficiency anemia and portal hypertensions]. 949 51

We describe a Black female who has suffered for many years from an (often) severe anemia (Hb 5-9 g/dl) with iron deficiency (serum Fe 8 microg/dl; TIBC 462 microg/dl; ferritin 7 ng/ml or less) and folate deficiency. The patient had hypermenorrhea which was appropriately treated resulting in an increase in hemoglobin level but not affecting the Fe deficiency. Splenomegaly was present, perhaps resulting from a clay-eating habit, although this was consistently denied. The patient had an alpha-thalassemia-2 (-3.7 kb) trait and a deletional hereditary persistence of fetal hemoglobin (HPFH) (type II) which were inherited from her father. Over the last six years the level of Hb F varied between 8.5 and 16% (25-29% in the father), while the G gamma value was also low (15-22% versus 32-34% in the father). Comparable reductions were seen in the relative levels of gamma-mRNA and G gamma-mRNA. These data support results published by Adams et al who showed a severe reduction in Hb F level in another HPFH heterozygote with Fe deficiency; these investigations suggested that a reduction in alpha-globin synthesis resulted in preferential formation of alpha beta dimers rather than alpha gamma dimers. Our data suggest that the decrease of Hb F and G gamma levels is due to a reduction in gamma-mRNA formation, mainly of the G gamma type, rather than through a posttranslational mechanism alone.
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PMID:Persistent iron and folate deficiency in a patient with deletional hereditary persistence of fetal hemoglobin; the effect on the relative levels of Hb F and G gamma chains and the corresponding mRNAs. 949 48

Recombinant human erythropoietin (EPO; epoetin) has been shown to be effective in improving anemia in a proportion of cancer patients. The response rate is approximately 60%, but varies considerably according to baseline hematocrit and transfusion needs, as well as the response criteria used. Response is not greatly influenced by the type of tumor, except in situations of major marrow involvement and limited residual hematopoiesis, or in the presence of specific mechanisms of anemia, such as hemolysis, splenomegaly, bleeding, hemodilution, or ineffective erythropoiesis. Stem cell damage by previous therapy as well as marrow suppression by current intensive chemotherapy can impair response. Besides its intensity, the type of chemotherapy may not be critical, although patients undergoing platinum-based chemotherapy may respond faster than those receiving non-platinum regimens. Complications, such as infections, bleeding, or nutritional deficiencies, may have a major negative impact on outcome. An important response-limiting factor is functional iron deficiency (ie, an imbalance between iron needs in the erythropoietic marrow and iron supply), which depends on the level of iron stores and its rate of mobilization. Functional iron deficiency is best monitored by the percentage of hypochromic red blood cells, and oral or intravenous iron supplements should be given when this percentage increases above 10%. All these factors explain why the response rate to epoetin is only approximately 60%. Therefore, it would be interesting to develop models that could help predict response to epoetin to help select the most appropriate cancer patients for this therapy. Few baseline parameters have been shown to be highly predictive of response in patients with solid tumors, although most studies in patients with myeloma or lymphoma have indicated that patients with a low baseline serum EPO level will respond better. Early changes after 2 to 4 weeks of treatment are also of great interest. Among these early changes, increments of soluble transferrin receptor, reticulocytes, and hemoglobin, as well as the persistence of elevated ferritin or EPO levels, have all shown some predictive value. Combination of baseline serum EPO and the 2-week increment of soluble transferrin receptor or hemoglobin may provide the best prediction of response.
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PMID:Prediction of response to optimize outcome of treatment with erythropoietin. 967 27

The anaemia associated with cancer can be effectively treated with recombinant human erythropoietin (rHuEpo) in about 60% of the patients. However, the response rate varies according to treatment modalities as well as the response criteria used. A number of disease- or chemotherapy-related factors determines the probability of response. Several specific mechanisms of anaemia, such as haemolysis, splenomegaly, bleeding, haemodilution, or ineffective erythropoiesis can seriously interfere with response. However, the type of tumor, in particular haematologic versus non-haematologic, is not critical, except in situations of major marrow involvement and limited residual haematopoiesis. Stem cell damage by previous therapy, reflected by low platelet counts or high transfusion needs, will impair response. In addition, marrow suppression by current intensive chemotherapy will also have a negative impact. Besides its intensity, the type of chemotherapy may not be critical, although patients undergoing platinum-based chemotherapy may respond faster than those receiving non-platinum regimens. Complications such as infections, bleeding or nutritional deficiencies may have a major negative impact on outcome. An important response-limiting factor is functional iron deficiency, i.e. an imbalance between iron needs in the erythropoietic marrow and iron supply, which depends on the level of iron stores and its rate of mobilisation. Therefore, oral or preferably intravenous iron supplements should be given when serum ferritin is below 40-100 micrograms/l, reflecting the absence of iron stores, or when the percentage of hypochromic red cells rises above 10%, indicating functional iron deficiency even in the presence of adequate storage iron. Because up to 40% of the patients will not respond to rHuEpo, it is of utmost importance to develop models that could help predict response to rHuEpo and thus select the most appropriate cancer patients for this therapy. Most studies of patients with myeloma or lymphoma have indicated that patients with a low baseline serum Epo level will respond better, but this is not true of patients with solid tumors. Also of considerable interest are early changes of erythropoietic parameters after 2 to 4 weeks of treatment, including increments of serum transferrin receptor (sTfR), reticulocytes and haemoglobin, as well as the persistence of elevated ferritin or Epo levels. Combination of baseline serum Epo and the 2-week increment of sTfR or haemoglobin may provide the best prediction of response.
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PMID:Prediction of response to treatment with recombinant human erythropoietin in anaemia associated with cancer. 978 36

The prevalence and age distribution of anemia and malaria among Yanomami Amerindians undergoing sociocultural assimilation are described. Anemia and malaria proportions were determined in 103 individuals randomly selected from 515 villagers in Mavaca in the southern Venezuelan Amazon. The age and sex distribution reflected that of the entire village cluster. Anemia (hematocrit less than World Health Organization/Centers for Disease Control and Prevention reference values) was found in 91% of the study population. As a group, adults (> or = 15 years old) had the highest proportion of anemia (P=0.037). Adult females had lower mean hematocrit values than adult males (P=0.013). The anemia was predominantly hypochromic and microcytic (62%), a finding that could suggest a diagnosis of iron deficiency in the absence of known hereditary hemoglobinopathies in these Amerindians. Malaria was diagnosed in 14% overall. Children (< 10 years old) displayed the highest proportion of Plasmodium falciparum (17%) and P. vivax (14%) parasitemia, splenomegaly (94%), and fever (34%) (P=0.059, 0.039, 0.005, and 0.008, respectively). The high proportions of anemia and splenomegaly observed in the survey may be used as indicators of inadequately controlled malaria in this community. Further studies to assess the epidemiology of risk factors for the high prevalence of anemia, and predominance of P. falciparum infections in the area are urgently needed.
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PMID:Anemia and malaria in a Yanomami Amerindian population from the southern Venezuelan Amazon. 988 12

The present study describes clinicopathological criteria to distinguish the 5 sequential stages proposed by Wasserman et al in the natural history of newly diagnosed PV patients. The European Working Group on MPD (EWG.MPD) extended and modified the PVSG diagnostic criteria of PV by including bone marrow histopathology. From the results of prospective randomized studies in PV it became evident that new clinical trials in previously untreated PV patients should focus on comparing interferon-alpha, a non-leukemogenic approach, versus a potential leukemogenic myelosuppressive treatment modality. Hydroxyurea appears to be the least leukemogenic myelosuppressive agent in long-term prospective clinical PV-studies extending observation periods of more than 10 years. The rational for using IFN-alpha as a first-line treatment option in newly diagnosed PV-patient include its effectiveness to abate constitutional symptoms and to induce a complete remission thereby avoiding phlebotomy, iron deficiency, and macrocytosis associated with hydroxyurea. Moreover IFN-alpha may prevent or delay the development of postpolycythemic myelofibrosis if used early in the course of the disease. Clinicians will be reluctant to postpone the use of hydroxyurea in early stage PV as long as a conservative approach using phlebotomy aiming at a hematocrit below 0.45, plus low-dose aspirin for the control platelet function or anagrelide for the control platelet number is used to keep the patient healthy. Low-dose aspirin will prevent the microvascular thrombotic complications of thrombocythemia associated with PV in remission after phlebotomy, but lacks myelosuppressive activity. Control of megakaryocyte maturation and reduction of platelet production to normal (<400 x 10(9)/l) by relatively low doses of anagrelide will predict a significant reduction of vascular complications in the early stages of PV, may prevent progression to myelofibrosis during follow-up of PV and very probable will postpone the use of hydroxyurea treatment for controlling the platelet count in PV. Large scale randomized clinical trials in PV are proposed, which should aim not only for clinical and hematological response, safety, efficacy, but should also assess toxicity, the need for phlebotomy and whether the development of progressive disease such as splenomegaly, pruritus, myelofibrotic myeloid metaplasia, spent phase, myelodysplasia and acute leukemia can be delayed or prevented by IFN-alpha as compared to a conservative approach of phlebotomy plus low-dose aspirin or anagrelide followed by hydroxyurea when signs of myeloproliferative activity became evident.
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PMID:Diagnosis and treatment of polycythemia vera and possible future study designs of the PVSG. 1067 96

A cohort of 250 Ghanaian schoolchildren aged 5-15 years was followed clinically and parasitologically for 4 months in 1997/98 in order to study the effect of asymptomatic Plasmodium falciparum infections on haematological indices and bone-marrow responses. Of the 250 children 65 met the predefined study criteria. Thus, 14 children were parasite-free throughout (group 1), 44 had P. falciparum in all blood samples collected but no symptoms of malaria (group 2), and 7 had 1 malaria attack during the study period (group 3). At the end of the study the mean haemoglobin (Hb) level in group 1 was 123 g/L, significantly higher than the value of 114 g/L in groups 2 and 3 (P < 0.02, adjusted for age and splenomegaly). The low Hb in group 2 was associated with subnormal plasma iron. Low Hb was associated with elevated erythropoietin (EPO) levels, and there was a positive correlation between EPO and reticulocyte counts. However, the reticulocyte response to EPO was more pronounced in uninfected than in infected children, suggesting a partial interference with erythropoiesis in asymptomatic infections. Children with asymptomatic infections had significantly higher plasma levels of tumour necrosis factor than uninfected children (geometric means 50 ng/L and 27 ng/L, respectively, P < 0.001) and this cytokine may contribute to bone-marrow suppression and disturbed iron metabolism. We suggest that asymptomatic malaria leads to a homeostatic imbalance in which erythrocyte loss due to parasite replication is only partially compensated for by increased erythropoiesis. The consequences of the reduced Hb levels on the development and cognitive abilities of children with asymptomatic infections, and the risk of precipitation of iron deficiency, deserve further study and should be considered in malaria control programmes that aim at reducing morbidity rather than transmission.
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PMID:Anaemia caused by asymptomatic Plasmodium falciparum infection in semi-immune African schoolchildren. 1071 50

Thrombocytosis is a common feature of myeloproliferative disorders but may also result from various conditions including chronic iron deficiency, hemorrhage, chronic inflammation and splenectomy. We report two cases of secondary thrombocytosis caused by isolated and congenital asplenia, mimicking essential thrombocythemia. These two adult cases of spleen agenesis were unexpected. We conclude that in thrombocytosis without clinical evidence of splenomegaly, attentive screening of blood in search of Howell-Jolly bodies and abdominal ultrasonography should always be performed not only to detect mild spleen enlargement but also to make sure of the presence of this organ.
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PMID:Isolated spleen agenesis: a rare cause of thrombocytosis mimicking essential thrombocythemia. 1106 71

The Philadelphia chromosome-negative chronic myeloproliferative disorders (CMPD), polycythemia vera (PV), essential thrombocythemia (ET) and chronic idiopathic myelofibrosis (IMF), have overlapping clinical features but exhibit different natural histories and different therapeutic requirements. Phenotypic mimicry amongst these disorders and between them and nonclonal hematopoietic disorders, lack of clonal diagnostic markers, lack of understanding of their molecular basis and paucity of controlled, prospective therapeutic trials have made the diagnosis and management of PV, ET and IMF difficult. In Section I, Dr. Jerry Spivak introduces current clinical controversies involving the CMPD, in particular the diagnostic challenges. Two new molecular assays may prove useful in the diagnosis and classification of CMPD. In 2000, the overexpression in PV granulocytes of the mRNA for the neutrophil antigen NBI/CD177, a member of the uPAR/Ly6/CD59 family of plasma membrane proteins, was documented. Overexpression of PRV-1 mRNA appeared to be specific for PV since it was not observed in secondary erythrocytosis. At this time, it appears that overexpression of granulocyte PRV-1 in the presence of an elevated red cell mass supports a diagnosis of PV; absence of PRV-1 expression, however, should not be grounds for excluding PV as a diagnostic possibility. Impaired expression of Mpl, the receptor for thrombopoietin, in platelets and megakaryocytes has been first described in PV, but it has also been observed in some patients with ET and IMF. The biologic basis appears to be either alternative splicing of Mpl mRNA or a single nucleotide polymorphism, both of which involve Mpl exon 2 and both of which lead to impaired posttranslational glycosylation and a dominant negative effect on normal Mpl expression. To date, no Mpl DNA structural abnormality or mutation has been identified in PV, ET or IMF. In Section II, Dr. Tiziano Barbui reviews the best clinical evidence for treatment strategy design in PV and ET. Current recommendations for cytoreductive therapy in PV are still largely similar to those at the end of the PVSG era. Phlebotomy to reduce the red cell mass and keep it at a safe level (hematocrit < 45%) remains the cornerstone of treatment. Venesection is an effective and safe therapy and previous concerns about potential side effects, including severe iron deficiency and an increased tendency to thrombosis or myelofibrosis, were erroneous. Many patients require no other therapy for many years. For others, however, poor compliance to phlebotomy or progressive myeloproliferation, as indicated by increasing splenomegaly or very high leukocyte or platelet counts, may call for the introduction of cytoreductive drugs. In ET, the therapeutic trade-off between reducing thrombotic events and increasing the risk of leukemia with the use of cytoreductive drugs should be approached by patient risk stratification. Thrombotic deaths seem very rare in low-risk ET subjects and there are no data indicating that fatalities can be prevented by starting cytoreductive drugs early. Therefore, withholding chemotherapy might be justifiable in young, asymptomatic ET patients with a platelet count below 1500000/mm(3) and with no additional risk factors for thrombosis. If cardiovascular risk factors together with ET are identified (smoking, obesity, hypertension, hyperlipidemia) it is wise to consider platelet-lowering agents on an individual basis. In Section III, Dr. Gianni Tognoni discusses the role of aspirin therapy in PV based on the recently completed European Collaboration on Low-dose Aspirin in Polycythemia Vera (ECLAP) Study, a multi-country, multicenter project aimed at describing the natural history of PV as well as the efficacy of low-dose aspirin. Aspirin treatment lowered the risk of cardiovascular death, non-fatal myocardial infarction, and non-fatal stroke (relative risk 0.41 [95% CI 0.15-1.15], P =.0912). Total and cardiovascular mortality were also reduced by 46% and 59%, respectively. Major bleedings were slightly increased nonsignificnsignificantly by aspirin (relative risk 1.62, 95% CI 0.27-9.71). In Section IV, Dr. Giovanni Barosi reviews our current understanding of the pathophysiology of IMF and, in particular, the contributions of anomalous megakaryocyte proliferation, neoangiogenesis and abnormal CD34(+) stem cell trafficking to disease pathogenesis. The role of newer therapies, such as low-conditioning stem cell transplantation and thalidomide, is discussed in the context of a general treatment strategy for IMF. The results of a Phase II trial of low-dose thalidomide as a single agent in 63 patients with myelofibrosis with meloid metaplasia (MMM) using a dose-escalation design and an overall low dose of the drug (The European Collaboration on MMM) will be presented. Considering only patients who completed 4 weeks of treatment, 31% had a response: this was mostly due to a beneficial effect of thalidomide on patients with transfusion dependent anemia, 39% of whom abolished transfusions, patients with moderate to severe thrombocytopenia, 28% of whom increased their platelet count by more than 50 x 10(9)/L, and patients with the largest splenomegalies, 42% of whom reduced spleen size of more than 2 cm.
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PMID:Chronic myeloproliferative disorders. 1463 83


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