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

Of 138 patients with malaria, 90 were found to be having Plasmodium falciparum in their peripheral blood smears. Megaloblastosis alone or in combination with the other patterns of erythropoiesis was observed in 82.1 percent cases of chronic P. falciparum malaria as compared to 36.3 and 26.5 per cent cases of acute P. falciparum and P. vivax malaria respectively. Iron deficiency was observed in 15.5 percent cases of chronic P. falciparum, 18.2 per cent cases of acute P. falciparum and 13.3 per cent patients of P. vivax infection. Of patients with chronic falciparum malaria, 33.3 percent revealed features of both megaloblastosis and defective iron utilization and transient hypoplasia of marrow was observed in 8.9 per cent of these cases.
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PMID:Patterns of erythropoiesis and anaemia in malaria. 209 29

Anemia is the most common disorder in hospital patients in tropical Africa, and it is demonstrated in up to 70% of inpatients. Community studies indicate that as many as 40% of the children younger than 15 years of age, 63% of these being younger than 3 years, are anemic. Although the anemia is multifactorial in etiology, the interplay between malnutrition and infection is still the most important element in causing the morbidity and mortality attributed to childhood anemia in Africa. Although iron deficiency is the most common cause of nutritional anemia, P. falciparum malaria is the leading cause among the anemias of infectious origin. The role of other causative agents is highlighted in the discussion. The fact that effective treatment depends on accurate diagnosis is also emphasized.
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PMID:Malnutrition and infections as causes of childhood anemia in tropical Africa. 212 63

The prevalence of anaemia during pregnancy was investigated in relation to parasite and spleen rates of pregnant women living in a defined study area in rural Madang, Papua New Guinea. The effects in pregnancy of anaemia, iron deficiency and malaria on the foetus were investigated. There is a high prevalence of anaemia in this population, with 44% of primigravidae and 29% of multigravidae having severe anaemia [haemoglobin (Hb) less than 8 g dl-1] after 28 weeks gestation. The odds ratio for severe anaemia at 0-16 weeks gestation in pregnant compared to non-pregnant women was 4.7 (P less than 0.0001). Forty-seven per cent of primigravidae and 32% of multigravidae had evidence of iron deficiency with high free erythrocyte protoporphyrin values (greater than 35 micrograms dl-1 whole blood) at antenatal booking. The risk of severe anaemia was significantly associated with splenomegaly and iron deficiency for all gravidae (splenomegaly P less than 0.05; iron deficiency, P less than 0.0002). Hb values at delivery were higher than at first attendance, with the greatest difference between groups malaria-positive at booking and malaria-negative at delivery (primigravidae 1.5 g dl-1, P less than 0.01; multigravidae, 0.7 g dl-1, P less than 0.01), indicating that malaria prophylaxis was an important factor in controlling anaemia. Two Hb groups were defined on the basis of the cut-off at 8 g dl-1, which corresponded to the lower quartile value at booking and delivery. A significantly increased risk of low birthweight was shown for primigravidae with values below 8 g dl-1 (65% v. 27%, P less than 0.025), but the prematurity rate was not significantly increased, indicating that the majority of babies were growth-retarded. Early pregnancy anaemia and iron deficiency were related to the risk of low birthweight in primigravidae. Current parasitaemia at delivery appeared a less important factor, although primigravidae with severe anaemia and parasitaemia at delivery had the lowest birthweights. The extent to which malaria control, using drug treatment and chemoprophylaxis, can reduce the risk of low birthweight will vary in relation to the prevalence and causes of anaemia in women.
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PMID:Consequences of maternal anaemia on outcome of pregnancy in a malaria endemic area in Papua New Guinea. 218 86

The mechanism(s) underlying the apparent resistance to malaria in certain inherited red cell disorders and iron deficiency anaemia remain poorly understood. The possibility that microcytic erythrocytes might inhibit parasite development, by physical restriction or reduced supply of nutrients, has been considered for many years, and never formally investigated. We sought to determine whether in vitro growth studies of P. falciparum could provide evidence to suggest that small red cell size contributes to malaria resistance in those red cell disorders in which microcytosis is a characteristic feature. Invasion and development of P. falciparum in iron deficient red cells (mean values for mean cell volume [MCV] 66 fl, mean cell haemoglobin [MCH] 19 pg) and in the red cells of two gene deletion forms of alpha-thalassaemia (mean MCV 71 fl, MCH 22 pg) were normal, assessed both morphologically, and by 3H-hypoxanthine incorporation. Although parasite appearances were normal in all cell types, morphological abnormalities were noted in iron deficient and thalassaemic cells parasitized by mature stages of P. falciparum, notably cellular ballooning and extreme hypochromia of the red cell cytoplasm. Using electron microscopy, the red cell cytoplasm in parasitized thalassaemic cells showed reduced electron density and abnormal reticulation. Normal invasion rates were observed following schizogony in microcytic cells of both types. Our findings indicate that whilst minor morphological abnormalities may be detected in parasitized iron deficiency and thalassaemic erythrocytes, development of P. falciparum in these conditions is not limited by small erythrocyte size.
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PMID:Unrestricted growth of Plasmodium falciparum in microcytic erythrocytes in iron deficiency and thalassaemia. 218 91

Iron deficiency and vitamin A deficiency are both reported to predispose to infection morbidity and to mortality. In both situations, however, the data are insufficient to draw firm conclusions, primarily owing to flaws in the design of the studies. To be sure, these are difficult studies to carry out, and the investigators whose reports have been reviewed should be praised rather than adversely criticized for their efforts. In the case of iron deficiency, there is a further complication in interpretation, that is the suggestion that iron deficiency states may be protective and that conditions of iron overload may predispose to infection. These concepts appear to pertain most convincingly to malaria and Yersinia infections, and to situations in which iron dextran is given parenterally to young children in the first few months of life. There are still two few data to suggest that oral iron is harmful and there is no reason at present that it should not be employed for the correction of iron deficiency anemia.
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PMID:Micronutrients and susceptibility to infection. 219 69

Iron deficiency is prevalent in childhood in the developed and developing countries. Programs of presumptive therapy, mass supplementation and food fortification have been introduced in many countries. The unresolved debate over the interaction of iron and infection in the clinical setting prompts re-evaluation of these practices. Situations of iron overload are associated with increased susceptibility to certain infections, although the exact mechanisms may vary with the main pathology. Iron treatment has been associated with acute exacerbations of infection, in particular malaria. In most instances parenteral iron was used. In the neonate parenteral iron is associated with serious E. coli sepsis. In one country, with endemic malaria, parenteral iron was associated with increased rates of malaria and increased morbidity due to respiratory disease in infants. In contrast in non-malarious countries studies of oral iron supplementation have if anything shown a reduction in infectious morbidity. Methodological problems in the latter reports indicate the need for further controlled prospective studies with accurate morbidity recording if informed recommendations are to be made.
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PMID:Iron and infection: the clinical evidence. 187 85

The effect of iron therapy on malarial infection was investigated in Papua New Guinea, where malaria is endemic. Prepubescent schoolchildren with hemoglobin levels of 8-12 g/dl were randomly assigned to receive either 200 mg ferrous sulfate or a placebo twice daily for 16 weeks. Iron status and malarial infection were assessed at baseline, after 6 and 16 weeks of therapy, and 8 weeks after therapy was discontinued. Iron status was significantly improved by the treatment. The treatment did not significantly affect parasite rate, parasite density, or levels of anti-malarial IgG. No changes in spleen size were observed in either group. Furthermore, there was no significant difference between the groups in reported episodes of suspected malaria during the therapy. These results suggest that, in malaria endemic areas, oral treatment for iron deficiency can be carried out in semi-immune or immune schoolchildren without adverse consequences.
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PMID:The effect of iron therapy on malarial infection in Papua New Guinean schoolchildren. 264 55

The aetiology of severe anaemia (haemoglobin less than 7.0 g dl-1) has been studied in 37 pregnant Zambians. Aetiology was usually multiple; 31 (84%) had Plasmodium falciparum malaria, 23 (62%) were folate deficient, 13 (35%) were iron deficient, one had sickle-cell anaemia and one had the acquired immunodeficiency syndrome (AIDS). Folate deficiency was most often secondary to malarial haemolysis: iron deficiency was nutritional, but hookworm was contributory in about one-third of patients. The anaemia of malaria and folate deficiency was both more common and more severe than anaemia due to iron deficiency; it was seen in younger women although primigravidae were not over-represented, it occurred earlier in pregnancy, and was associated with low birthweight. AIDS must now be included in the differential diagnosis of anaemia in pregnancy. Vigorous antimalarial treatment and prophylaxis are essential in the management and prevention of anaemia in pregnancy. Total dose iron infusion is indicated only when severe iron deficiency anaemia has been proven, and must be accompanied by antimalarial therapy and folic acid supplements. Because of the risk of transmission of human immunodeficiency virus, it is more important than ever to prevent anaemia and malaria in pregnancy, and to give blood transfusion only as a life-saving treatment.
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PMID:The aetiology of severe anaemia in pregnancy in Ndola, Zambia. 268 77

Major causes of anaemia in pregnancy in tropical Africa are malaria, iron deficiency, folate deficiency and haemoglobinopathies: now there is added also the acquired immune deficiency syndrome (AIDS). Anaemia is often multifactorial, with the different causes interacting in a vicious cycle of depressed immunity, infection and malnutrition. Anaemia progresses through 3 stages: compensation, with breathlessness on exertion only; decompensation, with breathlessness at rest and haemoglobin (Hb) below about 70 g/litre; cardiac failure, with Hb below about 40 g/litre. Without treatment, over half of the women with haematocrit less than 0.13 and heart failure die. Maternal anaemia, malaria and deficiencies of iron and folate cause intrauterine growth retardation, premature delivery and, when severe, perinatal mortality. Surviving infants have low birthweights, immune deficiency and poor reserves of iron and folate. They have entered already the vicious cycle of infection, malnutrition and impaired immunity. Treatment with blood transfusions is even more hazardous since the advent of AIDS, and should be limited to saving the life of the mother. Treatment of malaria is complex as chloroquine-resistant strains are now common. Prevention remains relatively easy with proguanil and supplements of iron and folic acid and is highly cost-effective in the improvement of maternal and infant health; it is more important than ever as it avoids the unnecessary exposure of women and infants to HIV transmitted through blood transfusion.
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PMID:Tropical obstetrics and gynaecology. 1. Anaemia in pregnancy in tropical Africa. 269 76

A controlled trial of iron prophylaxis (3 ml intramuscular iron dextran) to two-month-old infants was carried out on the north coast of Papua New Guinea where there is high transmission of malaria. The initial hypothesis was that iron deficiency increased susceptibility to infections and thus iron supplementation in a situation of actual or potential iron deficiency would diminish this susceptibility. Findings detailed elsewhere indicate that the placebo control group became relatively iron deficient and that the iron dextran group had adequate iron stores and a higher mean haemoglobin; however, prevalence of malaria recorded in the field was higher in the iron dextran group. Analysis of field and hospital infectious morbidity in the trial indicated a deleterious effect of iron dextran for all causes and for respiratory infections (the main single reason for admission). Total duration of stay in hospital was significantly increased in the iron dextran group. Analysis of other factors showed a deleterious effect of low weight for height at the start of the trial; a significant positive correlation between birth haemoglobin and hospital morbidity rates and a positive interaction between haemoglobin and iron dextran on hospital morbidity. A possible association between malarial experience and other infectious morbidity is discussed.
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PMID:Effect of iron prophylaxis on morbidity due to infectious disease: report on clinical studies in Papua New Guinea. 310 Dec 42


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