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

This article reviews iron and vitamin B12 malabsorption due to the use of proton pump inhibitors (PPI) and infection with Helicobacter pylori. The bacterium is in some studies associated with low serum values of both ferritin and cobalamin and has in several cases been shown to cause reversible deficiency of these nutrients. PPI depresses absorption of vitamin B12, but only one case of deficiency has been reported in standard reflux therapy. Case reports exist of PPI-related iron deficiency, but studies have not confirmed these risks. General substitution with iron or B12 supplements in PPI therapy can't be advocated. The safety of long-term use of PPI is well documented, but it is still unclear whether PPI accelerates the development of atrophic corpus gastritis in the presence of H pylori.
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PMID:[Helicobacter pylori can in rare cases be the cause of iron and vitamin B 12 deficiency. No increased risk of iron and vitamin B 12 deficiency due to proton pump inhibitors]. 1523 39

There has been an increasing awareness recently of subtle, non-bleeding gastrointestinal conditions that may result in abnormal iron absorption leading to iron-deficiency anaemia (IDA) in the absence of gastrointestinal symptoms. Thus, the importance of coeliac disease as a possible cause of IDA refractory to oral iron treatment, without other manifestations of malabsorption syndrome, is increasingly being recognized. In addition, Helicobacter pylori has been implicated in several recent studies as a cause of IDA refractory to oral iron treatment, and the anaemia responds favourably to H. pylori eradication. Likewise, achlorhydric gastric atrophy or atrophic body gastritis (ABG), a condition associated with chronic idiopathic iron deficiency, has been shown to be responsible for refractory IDA in over 20% of patients with no evidence of gastrointestinal blood loss. It has also been suggested that H. pylori gastritis may represent an early phase of ABG in which infection may trigger an autoimmune process directed against gastric parietal cells by means of antigenic mimicry. In this review we examine in a critical manner the role of H. pylori gastritis in the causation of IDA, the role of ABG in the pathogenesis of iron malabsorption, the evidence supporting a possible cause-and-effect relationship between H. pylori gastritis and ABG, and the implications of these findings for the diagnostic work-up and management of IDA.
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PMID:Gastropathic sideropenia. 1573 96

Helicobacter pylori infection fulfills each of Koch's postulates as a human pathogen causing chronic active gastritis. Disease consequences that develop in a subset of infected subjects include peptic ulcerations, gastric adenocarcinoma and mucosa-associated lymphoid tissue lymphoma. More recently, multiple publications have advocated a role for H. pylori infection in causing a variety of extraintestinal manifestations. Many of these reports suffer from being case reports or case series without adequate controls. As a result, purported manifestations may simply be coincidental in nature. On the other hand, increasing evidence supports H. pylori infection as a cause of sideropenic (refractory iron deficiency) anemia. Moderate evidence supports H. pylori gastric infection as a cause of some cases of immune thrombocytopenic purpura due to molecular mimicry. Guidelines should be adjusted in accordance with advancing knowledge in the field.
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PMID:Extradigestive manifestation of Helicobacter pylori infection in children and adolescents. 1601 Mar 4

Iron deficiency is a known complication of achlorhydria and may precede the development of pernicious anemia. Among 160 patients with autoimmune gastritis identified by hypergastrinemia and strongly positive antiparietal antibodies, we explored the overlap between 83 subjects presenting with iron deficiency anemia (IDA), 48 with normocytic indices, and 29 with macrocytic anemia. Compared with macrocytic patients, patients with IDA were 21 years younger (41 +/- 15 years versus 62 +/- 15 years) and mostly women. All groups had a high prevalence of thyroid disease (20%) and diabetes (8%) suggestive of the autoimmune polyendocrine syndrome. Stratification by age cohorts from younger than 20 years to older than 60 years showed a regular and progressive increase in mean corpuscular volume (MCV) from 68 +/- 9 to 95 +/- 16 fl, serum ferritin levels from 4 +/- 2 to 37 +/- 41 microg/L, gastrin level from 166 +/- 118 to 382 +/- 299 pM/L (349 +/- 247 to 800 +/- 627 pg/mL), and a decrease in cobalamin level from 392 +/- 179 to 108 +/- 65 pg/mL. The prevalence of Helicobacter pylori infection was 87.5% at age younger than 20 years, 47% at age 20 to 40 years, 37.5% at 41 to 60 years, and 12.5% at age older than 60 years. These findings challenge the common notion that pernicious anemia is a disease of the elderly and imply a disease starting many years before the establishment of clinical cobalamin deficiency, by an autoimmune process likely triggered by H pylori.
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PMID:Variable hematologic presentation of autoimmune gastritis: age-related progression from iron deficiency to cobalamin depletion. 1700 59

The aim of the work was to study the level of vitamins C, B12 and folic acid in latent iron deficiency of different etiology (hipo- and anacid gastritis and menorrhagia). 81 patients with latent iron deficiency were investigated. Vitamin C levels were measured by refractometry, folic acid and vitamin B12 by radioimmune assay. The obtained results showed significant decrease of ascorbic acid and less apparent decrease of folic acid in the blood plasma. The content of vitamin B12 was unchanged. Decrease of vitamin C level is related to the changes of initial stages of iron metabolism and its further absorption. Less apparent changes of folic acid and vitamin B12 indicates, that such important stages of erithropoesis as DNA replication and cell proliferation are intact. Our results indicate to the development of metabolic disorders prior to revelation of iron deficiency anaemia, which need timely correction.
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PMID:[Vitamins C, B12 and folic acid in latent iron deficiency]. 1636 81

Autoimmune atrophic gastritis is encountered in 20-27% of patients with obscure, or refractory iron deficiency anemia and is 4 to 6 times more common than celiac disease causing unexplained iron deficiency. The unique clinical features of iron deficiency anemia associated with achlorhydria and mucosal atrophy sparing the gastric antrum have all been accurately described by Faber and others over 100 years ago, including its refractoriness to oral iron treatment, female predominance, relatively young age, increased prevalence of thyroid disease and tendency to progress to pernicious anemia. A significant new development is the relation between autoimmune gastritis and Helicobacter pylori infection. H. pylori per se impairs gastric acid secretion and it is quite likely that a proportion of patients described originally as achylia gastrica represented H. pylori and not autoimmune gastritis. The demonstration of H. pylori antibodies in atrophic gastritis directed against epitopes on gastric mucosal cells implies an autoimmune mechanism triggered by H. pylori and directed against gastric parietal cells by antigenic mimicry of H+K+-ATPase, the most common autoantigen in pernicious anemia. These findings introduce a new element into the 100-year-old saga of achylia gastrica and open new options for its prevention and management.
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PMID:The anemia of achylia gastrica revisited. 1749 46

Here, we report a rare coincidence of heterozygous hemoglobinopathy (Hb) Stanleyville II and severe pernicious anemia due to autoimmune gastritis. Hb Stanleyville II is characterized by a single base exchange (AAC-->AAA) resulting in a substitution Asn --> Lys at position 78 of hemoglobin alpha2-chain. Under normal conditions this hemoglobinopathy does not cause any symptoms even if present as homozygous variant. However, in our case diagnosis of pernicious anemia was hampered by the absence of typical erythrocytic macrocytosis and hyperchromasia. In addition, interpretation of bone marrow smears was difficult as characteristic findings for pernicious anemia were little pronounced. All known reasons for the absence of typical cytomorphologic signs in pernicious anemia as underlying iron deficiency and thalassemia could be excluded.
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PMID:Cytomorphologic signs of severe pernicious anemia obscured in a patient with heterozygous hemoglobin Stanleyville II. 1768 Aug 15

Pernicious anemia (PA) is a macrocytic anemia that is caused by vitamin B(12) deficiency, as a result of intrinsic factor deficiency. PA is associated with atrophic body gastritis (ABG), whose diagnosis is based on histological confirmation of gastric body atrophy. Serological markers that suggest oxyntic mucosa damage are increased fasting gastrin and decreased pepsinogen I. Without performing Schilling's test, intrinsic factor deficiency may not be proven, and intrinsic factor and parietal cell antibodies are useful surrogate markers of PA, with 73% sensitivity and 100% specificity. PA is mainly considered a disease of the elderly, but younger patients represent about 15% of patients. PA patients may seek medical advice due to symptoms related to anemia, such as weakness and asthenia. Less commonly, the disease is suspected to be caused by dyspepsia. PA is frequently associated with autoimmune thyroid disease (40%) and other autoimmune disorders, such as diabetes mellitus (10%), as part of the autoimmune polyendocrine syndrome. PA is the end-stage of ABG. Long-standing Helicobacter pylori infection probably plays a role in many patients with PA, in whom the active infectious process has been gradually replaced by an autoimmune disease that terminates in a burned-out infection and the irreversible destruction of the gastric body mucosa. Human leucocyte antigen-DR genotypes suggest a role for genetic susceptibility in PA. PA patients should be managed by cobalamin replacement treatment and monitoring for onset of iron deficiency. Moreover, they should be advised about possible gastrointestinal long-term consequences, such as gastric cancer and carcinoids.
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PMID:Pernicious anemia: new insights from a gastroenterological point of view. 2127 87

Despite elegant regulatory mechanisms, iron deficiency anemia (IDA) remains one of the most common nutritional deficiencies of mankind. Iron deficiency is the result of an interplay between increased host requirements, limited external supply, and increased blood loss. When related to increased physiologic needs associated with normal development, iron deficiency is designated physiologic or nutritional. By contrast, pathological iron deficiency, with the exception of gross menorrhagia, is most often the result of gastrointestinal disease associated with abnormal blood loss or malabsorption. If gastroenterologic evaluation fails to disclose a likely cause of IDA, or in patients refractory to oral iron treatment, screening for celiac disease (anti-tissue transglutaminase antibodies), autoimmune gastritis (gastrin, anti-parietal or anti-intrinsic factor antibodies), and Helicobacter pylori (IgG antibodies and urease breath test) is recommended. Recent studies indicate that 20-27% of patients with unexplained IDA have autoimmune gastritis, about 50% have evidence of active H. pylori infection, and 4-6% have celiac disease. The implications for abnormal iron absorption of celiac disease or autoimmune gastritis are obvious. In patients with unexplained IDA and H. pylori infection, cure of refractory IDA by H. pylori eradication offers strong evidence for a cause-and-effect relation between H. pylori infection and unexplained IDA. Stratification by age cohorts in autoimmune gastritis implies a disease presenting as IDA many years before the establishment of clinical cobalamin deficiency. It is likely caused by an autoimmune process triggered by antigenic mimicry between H. pylori epitopes and major autoantigens of the gastric mucosa. Recognition of the respective roles of H. pylori and autoimmune gastritis in the pathogenesis of iron deficiency may have a strong impact on the diagnostic workup and management of unexplained, or refractory IDA.
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PMID:Iron deficiency, Helicobacter infection and gastritis. 1990 46

Type 1 diabetes mellitus (T1DM) results from autoimmune destruction of insulin-producing beta cells and is characterised by the presence of insulitis and &and beta-cell autoantibodies. Up to one third of patients develop an autoimmune polyglandular syndrome. Fifteen to 30% of T1DM subjects have autoimmune thyroid disease (Hashimoto's or Graves' disease), 5 to 10% are diagnosed with autoimmune gastritis and/or pernicious anaemia (AIG /PA), 4 to 9% present with coeliac disease (CD), 0.5% have Addison's disease (AD), and 2 to 10% show vitiligo. These diseases are characterised by the presence of autoantibodies against thyroid peroxidase (for Hashimoto's thyroiditis), TSH receptor (for Graves' disease), parietal cell or intrinsic factor (for AIG /PA), tissue transglutaminase (for CD), and 21-hydroxylase (for AD). Early detection of antibodies and latent organ-specific dysfunction is advocated to alert physicians to take appropriate action in order to prevent full-blown disease. Hashimoto's hypothyroidism may cause weight gain, hyperlipidaemia, goitre, and may affect diabetes control, menses, and pregnancy outcome. In contrast, Graves' hyperthyroidism may induce weight loss, atrial fibrillation, heat intolerance, and ophthalmopathy. Autoimmune gastritis may manifest via iron deficiency or vitamin B12 deficiency anaemia with fatigue and painful neuropathy. Clinical features of coeliac disease include abdominal discomfort, growth abnormalities, infertility, low bone mineralisation, and iron deficiency anaemia. Adrenal insufficiency may cause vomiting, anorexia, hypoglycaemia, malaise, fatigue, muscular weakness, hyperkalaemia, hypotension, and generalised hyperpigmentation. Here we will review prevalence, pathogenetic factors, clinical features, and suggestions for screening, follow-up and treatment of patients with T1DM and/or autoimmune polyglandular syndrome.
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PMID:Type 1 diabetes and autoimmune polyglandular syndrome: a clinical review. 2000 14


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