Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002871 (anemia)
 52,094 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Systemic-onset juvenile chronic arthritis (SoJCA) is associated with high levels of circulating interleukin-6 (IL-6) and is frequently complicated by severe microcytic anemia whose pathogenesis is unclear. Therefore, we studied 20 consecutive SoJCA patients with hemoglobin (Hb) levels <12 g/dL, evaluating erythroid progenitor proliferation, endogenous erythropoietin production, body iron status, and iron supply for erythropoiesis. Hb concentrations ranged from 6.5 to 11.9 g/dL. Hb level was directly related to mean corpuscular volume (r = .82, P < .001) and inversely related to circulating transferrin receptor (r = -.81, P < .001) suggesting that the severity of anemia was directly proportional to the degree of iron-deficient erythropoiesis. Serum ferritin ranged from 18 to 1,660 microgram/L and was unrelated to Hb level. Bone marrow iron stores wore markedly reduced in the three children investigated, and they also showed increased serum transferrin receptor and normal-to-high serum ferritin. All 20 patients had elevated IL-6 levels and normal in vitro growth of erythroid progenitors. Endogenous erythropoietin (epo) production was appropriate for the degree of anemia as judged by both the observed to predicted log (serum epo) ratio 10.95 +/- 0.12) and a comparison of the serum epo-Hb regression found in these subjects with that of thalassemia patients. Multiple regression analysis showed that serum transferrin receptor was the parameter most closely related to hemoglobin concentration: variation in circulating transferrin receptor explained 61% of the variation in Hb level (P < .001). In 10 severely anemic patients, amelioration of anemia following intravenous iron administration resulted in normalization of serum transferrin receptor. Defective iron supply to the erythron rather than blunted epo production is the major cause of the microcytic anemia associated with SoJCA. A true body-iron deficiency caused by decreased iron absorption likely complicates long-lasting inflammation in the most anemic children, and this can be recognized by high serum transferrin receptor levels. Although oral iron is of no benefit, intravenous iron saccharate is a safe and effective means for improving iron availability for erythropoiesis and correcting this anemia. Thus, while chronically high endogenous IL-6 levels do not appear to blunt epo production, they are probably responsible for the observed abnormalities in iron metabolism. Anemia of chronic disease encompasses a variety of anemic conditions whose peculiar features may specifically correlate with the type of cytokine(s) predominantly released.
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PMID:Defective iron supply for erythropoiesis and adequate endogenous erythropoietin production in the anemia associated with systemic-onset juvenile chronic arthritis. 863 55

An attempt was made to create an expert system with sufficient accuracy to diagnose classes of anemia and report presumptive diagnoses directly on the hematology form. The system should simulate the processes of human experts who can reliably achieve diagnostic separability by pattern analysis. A hybrid expert system combining rule-based and artificial neural network (ANN) models was constructed to evaluate microcytic anemia in a 3-layered program using hematocrit (HCT), mean corpuscular volume (MCV), and coefficient of variation of cell distribution width (RDWcv) as inputs. These measurements are available as standard output on most hematology analyzers. Three categories of microcytic anemia were considered, iron deficiency (IDA), hemoglobinopathy (HEM), and anemia of chronic disease (ACD). A novel feature of the model is its construction and training using human expert input alone. Model construction is described in detail. The model's performance was evaluated with actual case data. It was successful in correctly classifying 96.5% of 473 documented cases of microcytic anemia and anemia of chronic disease. It thus exhibits sufficient accuracy for it to be considered for use in reporting microcytic anemia diagnoses on hematology forms.
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PMID:An expert system to diagnose anemia and report results directly on hematology forms. 868 71

Although the full mechanisms are not yet elucidated, research into the mechanism of toxicity of aluminum (Al) on bone formation and remodeling and on hematopoietic tissue is ongoing. In contrast little information exists on the interactive effects of systemic Al and the kidney. In bone, both clinically and experimentally, high doses of Al inhibit remodeling, slowing both osteoblast and osteoclast activities and producing osteomalacia and adynamic bone disease. In contrast, while very low levels of Al are mitogenic in bones of experimental animals, the effect of low levels of Al in humans is unknown. Aluminum has been shown to have its mitogenic action at the osteoblast, but whether the effect on resorption is viz osteoblast-directed changes in osteoclast activity has not yet been determined. Parathyroid hormone (PTH) levels are disrupted by Al in humans and animals. Whether altered PTH levels play a major or even a minor role in Al-dependent osteotoxicity requires clarification. In hematopoietic tissue, Al causes a microcytic anemia, not reversible by iron. Friend leukemia cells treated with Al have been reported to accumulate excess iron, without incorporating it into ferritin or heme. It is not yet known which steps in iron metabolism are disrupted by Al, if they involve a single mechanism of action, or even if this disruption in iron metabolism accounts for the anemia seen in Al toxicosis. In kidney, research is needed to evaluate Al nephrotoxicity; there are almost no studies in this area. Furthermore, research is needed to evaluate mechanisms of renal Al excretion, presently shown by one study to occur at the distal tubule. Such studies might well throw light on whether Al plays a role in aggravating renal insufficiency, or whether the role of the kidney in Al toxicosis is limited to the causative effect of renal compromise on Al accumulation. In summary, while a number of mechanisms have been proposed for the toxic action of Al, no single mechanism emerges to explain these diverse effects of systemic Al. Recommendations for future research are presented and summarized in Table 1.
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PMID:Systemic aluminum toxicity: effects on bone, hematopoietic tissue, and kidney. 877 4

Because anemia is a condition rather than a disease, an underlying cause must be determined when anemia is identified. Microcytic anemia is a common category of anemia. Iron deficiency anemia is the most common type of microcytic anemia and is also the most common anemia. The clinical presentation of anemia varies according to its severity. Anemias resulting from chronic disease and thalassemia are also relatively common types of microcytic anemia and should be differentiated from iron deficiency to avoid repeated unnecessary trials of iron therapy. Low serum ferritin is the best single laboratory parameter for the diagnosis of iron deficiency. Serum iron, total iron binding capacity and hemoglobin electrophoresis, if necessary, can help differentiate the type of microcytic anemia in patients with normal or elevated levels of serum ferritin. If the evaluation identifies iron deficiency as the type of anemia, the underlying cause must be investigated.
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PMID:Microcytic anemia. 916 44

Although disorders of iron metabolism are prevalent, iron transport remains poorly understood. To address this problem, we undertook a positional cloning strategy to identify the causative mutation in mice with microcytic anaemia (mk). Homozygous mk/mk mice have microcytic, hypochromic anaemia due to severe defects in intestinal iron absorption and erythroid iron utilization. We report the identification of a strong candidate gene for mk, and suggest that the phenotype is a consequence of a missense mutation in Nramp2 (ref. 5), a previously identified gene of unknown function. Nramp2 is homologous to Nramp1, a gene activa in host defense. If Nramp2 is mk, as the cumulative evidence suggests, our findings have broad implications for the understanding of iron transport and resistance to intracellular pathogens.
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PMID:Microcytic anaemia mice have a mutation in Nramp2, a candidate iron transporter gene. 924 Dec 78

Castleman's disease is a rare, benign disorder most commonly located in the mediastinum as a solitary mass. It is a lymphoid tissue disorder characterized by lymphoid proliferation. In this paper we describe a case of asymptomatic interlobar fissure tumor, localized Castleman's disease, hyaline vascular type, in a 30-year-old female. The tumor arose from the interlobar fissure between the right middle and lower lobes. Laboratory data revealed hypochromic microcytic anemia, similar to that found in iron deficiency, and an elevated erythrocyte sedimentation rate. She underwent video-assisted thoracic surgery for excision of the tumor. Anemia disappeared two months after surgery. No recurrence of the lung tumor was seen 19 months following surgery and she remains well.
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PMID:Castleman's disease: a case report. 926 Mar 74

Iron deficiency is the most common cause of anemia, and the most common cause of iron deficiency is bleeding from the gastrointestinal tract, or gynecological bleeding in the case of women. More rarely it may be due to an increased need for, or a reduction in the uptake of, iron. In addition to the usual clinical symptoms of anemia, there may also be symptoms affecting the skin, mucosae, and appendages of the skin. For the establishment of the diagnosis, the various causes of hypochromic, microcytic anemia must be differentiated, and the underlying cause of the iron deficiency clarified. With respect to treatment, the underlying disease is of primary importance. In the absence of absorption disorders or intolerability, oral replacement of iron in a suitable form is the substitution treatment of choice.
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PMID:[Basic principles and clinical significance of iron deficiency]. 948 Feb 50

This report describes the first case of homozygosity for the Hb Agrinio [alpha 29(B10)Leu-->Pro] alpha 2-globin gene variant (codon 29, CTG-->CCG) in a Greek patient. At 12 months of age, the proband presented with a marked hypochromic, microcytic anemia, a very low level of Hb H (< 2.5%), rare Hb H inclusions, and a balanced alpha/non-alpha biosynthesis ratio. The mother had hematological findings and globin biosynthesis consistent with heterozygous beta-thalassemia, but paradoxically, red cell morphology demonstrated very rare Hb H inclusions. The father had mild microcytosis and hypochromia. Analysis of alpha- and beta-globin genotypes demonstrated that the patient was homozygous for the highly unstable Hb Agrinio variant, caused by a T-->C mutation in codon 29 of the alpha 2-globin gene. At the age of 13 years, the proband had a clinical phenotype compatible with mild thalassemia intermedia with moderate anemia (Hb 7-8 g/dL), normal growth and development, slight splenomegaly, and minimal bone changes, while Hb H and inclusion bodies were not detected.
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PMID:An alpha-thalassemic hemoglobinopathy: homozygosity for the HB Agrinio alpha 2-globin chain variant. 962 96

During a 7-month period a prospective study of 71 anaemic patients (29 males and 42 females) over the age of 50 was undertaken in order to identify patients with myelodysplastic syndrome (MDS). The mean values of mean corpuscular volume (MCV), serum ferritin, folate, vitamin B12 and red cell folate (RCF) of patients grouped according to the diagnosis were compared to those observed in age-matched blood donors. Forty-four of the 71 elderly patients showed macrocytic anaemia: 21 of them had gastric disease and the remaining 23 MDS. Two further patients with MDS showed microcytic anaemia. The 25 patients diagnosed with MDS were subclassified according to the FAB nomenclature: 9 had a refractory anaemia with excess of blasts and 16 refractory anaemia. The mean values of MCV, serum folate, ferritin, vitamin B12 and RCF were statistically different between patients with macrocytic anaemia due to gastric disease and patients with MDS. Among patients with MDS, the RCF level pathologically high was inversely correlated to the haemoglobin level (r=-0.39; p<0.05). Thus the RCF and serum folate may represent useful parameters for the diagnosis of MDS in elderly anaemic patients.
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PMID:Red cell folate in elderly patients with myelodysplastic syndrome. 975 11

Megaloblastic anemia due to folic acid deficiency and ringed sideroblastic anemia have been reported in alcohol abusers. It has also been reported that vitamin B6 deficiency causes ringed sideroblastic anemia as well as microcytic anemia that is not associated with ringed sideroblasts. We encountered a case of macrocytic anemia with anisocytosis in a 75-year-old alcohol abuser who suffered vitamin B6 deficiency. Neither megaloblastic changes nor ringed sideroblasts were observed in specimens of the patient's bone marrow. Analyses of porphyrin content and heme biosynthetic enzyme activity suggested a decline in ALA-synthase activity (an enzyme that depends on vitamin B6) as well as decreased ferrochelatase activity or abnormal iron metabolism. Abstention from alcohol led to a reduction in mean corpuscular volume and the disappearance of Pappenheimer bodies commonly observed in the red blood cells of drinkers. Follow-up supplements of vitamin B6 resolved the patient's anisocytosis and anemia.
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PMID:[Macrocytic anemia with anisocytosis due to alcohol abuse and vitamin B6 deficiency]. 986 26


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