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)

A 73 year old woman was hospitalized for recurrent occult gastrointestinal bleeding. She had been treated with iron replacement for a microcytic anemia at the age of 67 years remaining on iron and was well until 1989, when she again was hospitalized with symptomatic anemia (hemoglobin 5.4 9um/dl). Urea, electrolytes, liver function, serum vitamin B12 and red cell folate tests were normal. The gastrointestinal blood loss continued, and she became dependent on transfusions, receiving 60 unites of blood over the course of a year. Investigation confirmed iron deficiency with occult blood loss, and showed antibodies to gastric parietal cells, with a title of 1:160. At gastroscopy a series of longitudinally arrayed red streaks were seen radiating to the pylorus, the typical appearances of antral vascular ectasia or watermelon stomach. The diagnosis was confirmed histologically. Prednisolone therapy, initially at a dose of 30 mg, successfully stopped the bleeding and other drugs were withdrawn except from carbimazole and tolbutamide. Prednisolone also restored the gastric acid secretion to normal (basal acid output 2.7 mEq/hour, peak acid output 14 mEq/hour) with a corresponding fall in gastrin to 70 pg/ml. However, prednisolone caused hyperglycemia even at a reduced dose of 10 mg/day. It was replaced by a standard estrogen-progesterone pill (loestrin 30) containing 30 mcg of ethinyl estradiol and 1.5 mg of norethisterone taken daily for 3 weeks each month. After an endoscopic antral biopsy she received 4 units of blood, but otherwise maintained her hemoglobin concentration on iron alone over this period with a considerable reduction in gastrointestinal bleeding.
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PMID:Gastric antral vascular ectasia: maintenance treatment with oestrogen-progesterone. 161 93

It is proposed that gastrin promotes the uptake of divalent and trivalent metal ions from the gastrointestinal lumen by catalyzing the binding of metal ions to luminal albumin and transferrin respectively. The following observations are consistent with this hypothesis: 1. Gastrin binds both divalent and trivalent metal ions. 2. Gastrin binds to both albumin and apotransferrin. 3. Binding of gastrin to albumin is enhanced by divalent metal ions. 4. Gastrin, albumin and transferrin are all present in gastric juice. 5. Surgical removal of the gastric mucosa results in iron deficiency.
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PMID:A new role for an old hormone: is gastrin a cofactor for dietary metal ion uptake? 161 60

Mucolipidosis type IV is an autosomal recessive lysosomal storage disease of unknown etiology that causes severe neurological and ophthalmological abnormalities. In an attempt to obtain insight into the nature of the metabolic abnormality in this disorder, we prospectively evaluated 15 consecutive patients, aged 2 to 23 years, over a period of 22 months. The finding of iron deficiency in some of the patients led us to the discovery that all patients but one had markedly elevated blood gastrin levels. None had vitamin B12 deficiency. Gastroscopy in three patients showed normal gross appearance of the mucosa in two patients, 4 and 7 years old, and mucosal atrophy in a 22-year-old. Parietal cells were present in normal numbers and contained large cytoplasmic inclusions that were confirmed immunohistochemically to be lysosomal in nature. Other gastric epithelial cells appeared normal. Parietal cells contained very few tubulovesicular membranes, suggesting cellular activation, whereas apical canaliculi appeared relatively nonactivated. Both subunits of the parietal cell H+/K+-ATPase were present, and both partially colocalized with f-actin at the apical membrane. We conclude that patients with mucolipidosis type IV are constitutively achlorhydric and have partially activated parietal cells. We hypothesize that the defective protein in this disease is closely associated with the final stages of parietal cell activation and is critical for a specific type of cellular vacuolar trafficking between the cytoplasm and the apical membrane domain.
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PMID:Constitutive achlorhydria in mucolipidosis type IV. 944 10

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

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

Gastrins are peptide hormones important for gastric acid secretion and growth of the gastrointestinal mucosa. We have previously demonstrated that ferric ions bind to gastrins, that the gastrin-ferric ion complex interacts with the iron transport protein transferrin in vitro, and that circulating gastrin concentrations positively correlate with transferrin saturation in vivo. Here we report the effect of long-term dietary iron modification on gastrin-deficient (Gas(-/-)) and hypergastrinemic cholecystokinin receptor 2-deficient (Cck2r(-/-)) mice, both of which have reduced basal gastric acid secretion. Iron homeostasis in both strains appeared normal unless the animals were challenged by iron deficiency. When fed an iron-deficient diet, Gas(-/-) mice, but not Cck2r(-/-) mice, developed severe anemia. In iron-deficient Gas(-/-) mice, massive splenomegaly was also apparent with an increased number of splenic megakaryocytes accompanied by thrombocytosis. The expression of the mRNA encoding the iron-regulatory peptide hepcidin, Hamp, was down-regulated in both Cck2r(-/-) and Gas(-/-) mice on a low-iron diet, but, interestingly, the reduction was greater in Cck2r(-/-) mice and smaller in Gas(-/-) mice than in the corresponding wild-type strains. These data suggest that gastrins play an important direct role, unrelated to their ability to stimulate acid secretion, in hematopoiesis under conditions of iron deficiency.
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PMID:Gastrin-deficient mice have disturbed hematopoiesis in response to iron deficiency. 2165 29

Pernicious anemia is a macrocytic anemia due to cobalamin deficiency, which is the result of intrinsic factor deficiency. Pernicious anemia is associated with atrophic body gastritis, whose diagnostic criteria are based on the histologic evidence of gastric body atrophy associated with hypochlorhydria. Serological markers suggesting the presence of oxyntic mucosa damage are increased levels of fasting gastrin and decreased levels of Pepsinogen I. Without the now obsolete Schilling's test, intrinsic factor deficiency may not be proven, and gastric intrinsic factor output after pentagastric stimulation has been proposed. Intrinsic factor autoantibodies are useful surrogate markers of pernicious anemia. The management of patients with pernicious anemia should focus on the life-long replacement treatment with cobalamin and the monitoring to early diagnose an eventual onset of iron deficiency. Moreover, these patients should be advised about possible gastrointestinal long-term consequences, such as gastric cancer and carcinoids.
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PMID:Diagnosis and management of pernicious anemia. 2194 76