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)

Vitamin B12 deficiency develops over a slowly progressive continuum. Early manifestations may be generalized weakness or fatigue, indigestion, diarrhea, or depression. Pernicious anemia is considered the classic cause, but others include malabsorption because of achlorhydria or other gastric dysfunction, fish tapeworm infection, and strict vegetarianism. Iron deficiency often coexists. Because presentation is often atypical, vitamin B12 deficiency is a diagnostic consideration whenever neuropsychiatric signs or symptoms are unexplained.
 ...
PMID:Vitamin B12 deficiency. Important new concepts in recognition. 220 95

Prior to 1960 a Polya gastrectomy was the most frequent operation for duodenal ulcer. The majority of these patients now have reached the age of sixty or older. A prospective longitudinal study of a cohort of patients who underwent gastrectomy between 1955 and 1960 was undertaken. Twenty five to thirty years later the study has revealed the extent of the nutritional problems that may arise with the passage of time and shows that these numerically far outweigh the mechanical post-gastrectomy syndromes and weight loss which tended to dominate the earlier post-gastrectomy scene. By the end of the first decade, iron deficiency was the commonest nutritional problem. Vitamin B12 deficiency assumed more importance in the second decade. During the third decade both reached equal prevalence, being found in some 90% of the female and 70% of the male residual population. Vitamin D deficiency and early osteomalacia was a lesser problem, reaching its climax in the second decade. Evidence suggested a high incidence of osteoporosis and this requires further investigation. Overall, women fared worse than men with a higher and earlier incidence of iron deficiency, particularly in the pre-menopausal group. This study emphasizes the increasing need for regular screening of post-gastrectomy patients to detect early iron, vitamin B12 and vitamin D deficiencies as patients grow older.
 ...
PMID:A gastrectomy population: 25-30 years on. 221 95

The effect of azidothymidine (Zidovudine, AZT) on pyrimidine (thymidine, deoxyuridine, and thymidine triphosphate) incorporation into DNA in folate- and/or vitamin B12-deficient and normal human bone marrow cells was studied to investigate whether such vitamin deficiency affects susceptibility to AZT-induced hematologic toxicity. Bone marrow cells from 12 patients were studied: 5 had folate and/or vitamin B12 deficiency; 7 controls included 5 with anemia related to chronic disease and 2 with iron deficiency. At 0.2 microM AZT (3 hr, 37 degrees C), the approximate pharmacologic serum trough level, pyrimidine incorporation into DNA was suppressed by 12 to 19% in folate- and/or vitamin B12-deficient cells and by 16 to 23% in normal cells. At 2.0 microM AZT (3 hr, 37 degrees C), the approximate pharmacologic serum peak level, this was suppressed by 15 to 40% in folate- and/or vitamin B12-deficient cells and by 32 to 47% in controls. Deoxyuridine incorporation into DNA was inhibited significantly greater than thymidine at 2.0 microM AZT (3 hr, 37 degrees C) in both groups. Inhibition of deoxyuridine incorporation was not reversed with methyltetrahydrofolate or vitamin B12. There tended to be less striking suppression by AZT of deoxyuridine incorporation into DNA in bone marrow cells from vitamin B12-deficient patients, which was made more striking by adding vitamin B12. This suggests that some of what passes for "AZT damage" to bone marrow cells may in fact be coincident deficiency of vitamin B12. AZT inhibition of DNA synthesis in 3 hr bone marrow cultures is relatively consistent in a variety of hematologic disorders. As approximately two-thirds of AIDS patients appear to be in negative balance with respect to folate and/or vitamin B12, the fact that AZT-induced inhibition of pyrimidine incorporation into DNA is occurring in cells which may be megaloblastic, i.e., in a state of impaired DNA synthesis, suggests that these cells may be more susceptible to AZT toxicity. The data also support the notion that AZT inhibition results predominantly from termination of DNA chain elongation. Whether folate or vitamin B12 supplementation may partially overcome apparent "AZT inhibition" of DNA synthesis (hematologic toxicity) and whether the benefit of such therapy exceeds the risk will require further study.
 ...
PMID:Synergy of inhibition of DNA synthesis in human bone marrow by azidothymidine plus deficiency of folate and/or vitamin B12? 230 78

Thirty six patients with rheumatoid arthritis (RA) (25 with anaemia) were studied to establish the role of iron, vitamin B12, and folic acid deficiency, erythropoietin responsiveness, and iron absorption in the diagnosis and pathogenesis of anaemia in RA. Iron deficiency, assessed by stainable bone marrow iron content, occurred in 13/25 (52%), vitamin B12 deficiency in 7/24 (29%), and folic acid deficiency in 5/24 (21%) of the anaemic patients. Only 8/25 (32%) had just one type of anaemia. The iron deficiency of anaemia of chronic disease (ACD) was distinguished by ferritin concentration, which was higher in that group. Mean cell volume (MCV) and mean cell haemoglobin (MCH) were lower in both anaemic groups, but most pronounced in iron deficient patients. Folic acid, and especially vitamin B12 deficiency, masked iron deficiency by increasing the MCV and MCH. Iron absorption tended to be highest in iron deficiency and lowest in ACD, suggesting that decreased iron absorption is not a cause of ACD in RA. No specific causes were found for vitamin B12 or folic acid deficiency. Haemoglobin concentration was negatively correlated with erythrocyte sedimentation rate in the group with ACD. Erythropoietin response was lower in ACD than in iron deficient patients. It was concluded that generally more than one type of anaemia is present simultaneously in anaemic patients with RA. The diagnosis of each type may be masked by another. Studies on pathogenesis of the anaemia are difficult as deficiencies generally coexist with ACD. Disease activity and, possibly, erythropoietin responsiveness are major factors in ACD pathogenesis.
 ...
PMID:Anaemia in rheumatoid arthritis: the role of iron, vitamin B12, and folic acid deficiency, and erythropoietin responsiveness. 231 22

Proteins, some minerals and vitamins, play important roles in erythropoiesis and the survival of the red blood cell. This article deals specifically with the physiological requirements and recommended intakes of iron, folate and vitamin B12. A comparison of the physiologic iron requirements according to age and sex, and the amount of iron which is actually absorbed from the diets consumed by the lower socioeconomic strata of the Venezuelan population; indicates that these diets do not satisfy the requirements at all ages. Such disparity is most marked in children below three years of age, in adolescents and in women during their reproductive age. Failure to do so leads to varying degrees of iron deficiency. This low bioavailability of the Venezuelan diet is also observed in other Latin American diets consumed by the same low socioeconomic strata, which explains the high prevalence of iron-deficiency anemia in the vulnerable groups. The low intake of fruits and vegetables by the lower socioeconomic strata of the Latin American population prevents these sectors from consuming an adequate intake of folate, failing to fulfill the daily recommended intake (3.3 - 3.6 micrograms/kg body weight). This situation is aggravated in pregnant and lactating women who require an additional intake of 300 micrograms and 100 micrograms, respectively. Prevalence of folate deficiency in the first stage may be in the order of 30% in some regions. In the second stage of deficiency, characterized by megaloblastic changes in the bone marrow and an erythrocyte folate concentration of less than 50 micrograms/lt, it could be as high as 40% in pregnant women. Nutritional vitamin B12 deficiency does not constitute a health problem in Latin America. Various surveys in the lower socioeconomic strata have reported normal or higher than normal serum B12 concentrations, compared to well-nourished populations.
 ...
PMID:[Requirements of nutrients which participate in erythropoiesis]. 315 30

A nutritional anaemia survey was carried out in 224 pregnant coloured first-time attenders at Coronation Hospital antenatal clinic in Johannesburg during the second quarter of 1986. None had received any form of nutritional supplementation during pregnancy. Haemoglobin concentrations less than 11 g/dl were present in 18.9% of women in the third trimester of pregnancy, while 64% had a saturation of transferrin value of less than 16% and 68% a serum ferritin level less than 12 micrograms/l. Calculations suggested that mean iron stores in the first trimester were 228 mg, with 37.5% of women having absent stores. Comparable figures in the second and third trimesters were 74 mg and -92 mg respectively. The fact that many were iron deficient in the first trimester indicates a high frequency of iron deficiency in non-pregnant women in this population group. Although 20.8% of the women had red cell folate values below the normal range for non-pregnant subjects, folate deficiency did not appear to be a significant problem. Vitamin B12 deficiency was very uncommon.
 ...
PMID:Nutritional anaemia in pregnant coloured women in Johannesburg. 335 30

The red blood cell distribution width (RDW) was studied in 26 unselected patients with untreated pernicious anemia. RDW changes were also sequentially followed after therapy in 12 patients. The mean (+/- 1 SD) RDW values were significantly higher in pernicious anemia patients than in controls (21.7 +/- 9.1% vs. 13.2 +/- 1.1%, P less than 0.0001). Nevertheless, 31% of the patients had normal RDWs. There were no consistent findings among those who had normal RDW. Most of them were in the early stages of deficiency, but some had advanced deficiency. Over half of those with normal RDW also had normal mean corpuscular volume (MCV). Overall, 9 of the 26 patients (35%) had normal MCV. Of eight patients whose RDW fell with therapy, some showed a steady fall while others had a transient rise followed by a progressive drop. Despite current advocacy that a high RDW is a sensitive and consistent finding in vitamin B12 deficiency, our findings show that a large proportion of untreated pernicious anemia patients have normal RDWs and that in contrast to iron deficiency, elevation of RDW is not necessarily the earliest indicator of vitamin B12 deficiency.
 ...
PMID:Red blood cell distribution width in untreated pernicious anemia. 335 71

To evaluate the long-term frequency and severity of anemia and selected vitamin and mineral deficiencies after gastric exclusion surgery for morbid obesity, the authors prospectively examined hematologic and nutritional parameters in 150 consecutive patients. These patients underwent a standardized gastric exclusion procedure during a six-year period (1976-1982) and were closely followed for up to seven years (mean, 33.2 months). Anemia developed in 36.8% of the population at a mean time from operation of 20 months. It was more frequent in women than in men (p less than 0.01), and it required transfusions in 3.5% of the population. A low serum iron concentration developed in 48.6%, iron deficiency in 47.2%, a low serum vitamin B12 concentration in 70.1%, vitamin B12 deficiency in 39.6%, and RBC folate deficiency in 18% of the population. Both iron and folate deficiencies responded to oral replacement. As a result of the high frequency and severity of anemia and nutritional deficiencies noted, all gastric exclusion patients should, as a minimum, be placed on oral multivitamin preparations containing iron, folate and vitamin B12. In addition, it is imperative that these patients be followed closely for the remainder of their lives with appropriate studies and replacement as necessary.
 ...
PMID:Prospective hematologic evaluation of gastric exclusion surgery for morbid obesity. 397 May 98

The haematological variables, haematinic state, and placental function of more than 2000 pregnant women, heterozygous for either alpha- or beta-thalassaemia genes, were examined during pregnancy. Four features emerged. Firstly, it was possible by discriminant function analysis of haematological variables to distinguish in pregnant patients between the anaemia caused by thalassaemia trait and that caused by iron deficiency. Secondly, patients with thalassaemia become significantly more anaemic in pregnancy, beta more than alpha, but this was mainly due to plasma dilution. From the data percentile curves were drawn for each type of thalassaemia which predicted the patients' expected "normal" haemoglobin throughout gestation. Thirdly, patients with alpha-thalassaemia had the same incidence of iron deficiency as normal pregnant patients, whereas in those with beta-thalassaemia it was four times less common. The incidence of folic acid and vitamin B12 deficiency was the same in all groups. Finally, as assessed by serum oestriol concentration, there did not appear to be any abnormality of placental function or fetal development associated with maternal thalassaemia, and, also, there seemed to be no increase in maternal or fetal morbidity in pregnancy.
 ...
PMID:Thalassaemia trait and pregnancy. 401 2

Enlarged spleen, fever, increased susceptibility to infections, and thrombocytosis, are manifestations of iron deficiency which are relatively specific of pediatric patients. Iron deficiency anemia is part of everyday pediatrics. Patients are referred to the hematologist in the following situations: 1) Therapy is ineffective for one of the following reasons: the hypochromic anemia is not caused by iron deficiency (hemoglobinopathies); iron is less efficiently used because of transferrin deficiency or infectious, inflammatory or cancerous disease; iron therapy is inadequate either because of insufficient dosage or of suboptimal duration. 2) A relapse occurs in spite of adequate therapy. Before investigating the digestive tract, abnormal hemostasis. Osler-Weber-Rendu syndrome and pulmonary hemosiderosis should be considered. 3) Iron deficiency anemia is less common in adolescents. This condition, known as chlorosis, results mainly from increased needs, unbalanced diet, and onset of menses. In some cases no explanation is found but iron therapy leads to recovery. 4) Difficult problems arise in patients with complex anemias: iron deficiency with folic acid or vitamin B12 deficiency; hyposideremia complicating one of the hemoglobinopathies.
 ...
PMID:[Iron-deficiency anemia. Hematologist's viewpoint]. 629 49


<< Previous 1 2 3 4 5 6 7 Next >>