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Concept: Iron deficiency anemia

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AIMS: Acute Helicobacter pylori infection is associated with transient hypochlorhydria. In H pylori-associated atrophy, hypochlorhydria has a role in iron deficiency (ID) through changes in the physiology of iron-complex absorption. The aims were to evaluate the association between H pylori-associated hypochlorhydria and ID in children. METHODS: Symptomatic children (n=123) were prospectively enrolled. Blood, gastric juice and gastric biopsies were taken, respectively, for haematological analyses, pH assessment and H pylori determination, and duodenal biopsies for exclusion of coeliac disease. Stool samples were collected for parasitology/microbiology. Thirteen children were excluded following parasitology and duodenal histopathology, and five due to impaired blood analysis. RESULTS: Ten children were hypochlorhydric (pH>4) and 33 were H pylori positive. In H pylori-positive children with pH>4 (n=6) serum iron and transferrin saturation levels % were significantly lower (p<0.01) than H pylori-positive children with pH≤4. No differences in ferritin, or total iron binding capacity, were observed. In H pylori-negative children with pH>4, iron and transferrin saturation were not significantly different from children with pH≤4. CONCLUSIONS: Low serum iron and transferrin in childhood H pylori infection is associated with hypochlorhydria. In uninfected children, hypochlorhydria was not associated with altered serum iron parameters, indicating a combination of H pylori infection and/or inflammation, and hypochlorhydria has a role in the aetiology of ID. Although H pylori-associated hypochlorhydria is transient during acute gastritis, this alters iron homeostasis with clinical impact in developing countries with a high H pylori prevalence.

Concepts: Gastroenterology, Stomach, Helicobacter pylori, Iron deficiency anemia, Gastritis, Transferrin, Transferrin saturation, Total iron-binding capacity

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Anemia often complicates the course of Inflammatory Bowel Disease (IBD). Hepcidin, a liver-produced peptide hormone, is a key mediator of anemia of chronic disease (ACD). We hypothesized that hepcidin is significantly elevated in anemic CD patients and that hepcidin may cause iron restriction and, therefore, mediate ACD. METHODS: We enrolled 17 patients with CD and ACD recruited from the Cedars-Sinai IBD Center. Routine blood tests included hemoglobin (Hgb), hematocrit, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). Anemia was defined as hemoglobin <12g/dL and <13.5g/dL, in men and women, respectively. ACD was diagnosed on the basis of a combination of the following: a) normal or elevated ferritin b) lowered serum iron and total iron binding capacity and c) normal percent iron saturation. Serum and urine hepcidin, as well as IL-6 levels were also measured. Patients with documented iron-deficiency anemia were excluded. RESULTS: There was an excellent correlation between urine (expressed as ng/mg of creatinine) and serum hepcidin levels expressed as ng/ml (r=0.853, p<0.001). We also found a strong positive correlation between serum hepcidin and ferritin levels (r=0.723, p=0.0015). There was a positive correlation between serum hepcidin and IL-6 levels (r=0.546, p=0.023). We found a strong negative correlation between serum hepcidin concentrations and Hgb levels (r=0.528, p=0.029). CONCLUSION: We demonstrate that ACD in CD is characterized by high serum IL-6 and hepcidin levels, which negatively correlate with Hgb levels. Our data support the hypothesis that IL-6-driven hepcidin production mediates ACD in patients with CD.

Concepts: Hemoglobin, Red blood cell, Anemia, Inflammatory bowel disease, Iron deficiency anemia, Transferrin, Ferritin, Total iron-binding capacity

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Repeated blood transfusions in patients with sickle cell anemia (SCA) increases the risk of iron overload (IO), contributing to oxidative stress. Materials & methods: Blood samples of 15 SCA patients without IO (group 1) and 15 SCA patients with IO (group 2) and 30 healthy individuals were collected to investigate oxidative stress. IO was categorized using repeated measures of serum ferritin. The biomarkers evaluated were plasmatic malondialdehyde (MDA), nitrite and erythrocyte catalase. Results: MDA and nitrite were higher in group 2 than in group 1 and the healthy group (p < 0.001 for MDA and nitrite). Catalase presented lower in group 2 than group 1 and the healthy group (p < 0.001). We obtained a positive correlation between ferritin and MDA (r = 0.40; p < 0.02), and between ferritin and nitrite (r = 0359; p = 0.023). Conclusion: The results demonstrated that IO is an important risk factor for enhanced oxidative stress in SCA.

Concepts: Blood, Malaria, Red blood cell, Anemia, Hematology, Iron deficiency anemia, Sickle-cell disease, Blood transfusion

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Abstract Anemia is a global health issue with disproportionately high prevalence in women. In addition to being an independent risk factor for decreased quality of life and increased morbidity and mortality, anemia in women has been linked to unfavorable outcomes of pregnancy and other issues for children born to anemic women. Iron deficiency is the leading cause of anemia in many populations. Guidelines recommend proactive screening for anemia, particularly in the preoperative setting. Once anemia is diagnosed, treatment should be based on etiology (most commonly, iron deficiency followed, in order of prevalence, by inflammation or chronic disease). Iron supplementation (oral and intravenous) offers safe and effective treatment for anemia associated with iron deficiency. Anemia of chronic disease may be more challenging to treat, and attention must be given to the underlying disease, along with use of hematinic agents. Given its enormous impact on the health and well-being of women and the availability of simple and effective treatment options, anemia should never be left unmanaged.

Concepts: Hemoglobin, Medicine, Epidemiology, Anemia, Iron deficiency anemia, Transferrin, Human iron metabolism, Microcytic anemia

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Ferroportin exports iron into plasma from absorptive enterocytes, erythrophagocytosing macrophages, and hepatic stores. The hormone hepcidin controls cellular iron export and plasma iron concentrations by binding to ferroportin and causing its internalization and degradation. We explored the mechanism of hepcidin-induced endocytosis of ferroportin, the key molecular event in systemic iron homeostasis. Hepcidin binding caused rapid ubiquitination of ferroportin in cell lines overexpressing ferroportin and in murine bone marrow-derived macrophages. No hepcidin-dependent ubiquitination was observed in C326S ferroportin mutant which does not bind hepcidin. Substitutions of lysines between residues 229 and 269 in the third cytoplasmic loop of ferroportin prevented hepcidin-dependent ubiquitination and endocytosis of ferroportin, and promoted cellular iron export even in the presence of hepcidin. The human ferroportin mutation K240E, previously associated with clinical iron overload, caused hepcidin resistance in vitro by interfering with ferroportin ubiquitination. Our study demonstrates that ubiquitination is the functionally relevant signal for hepcidin-induced ferroportin endocytosis.

Concepts: Cell, Hematology, Iron deficiency anemia, Human iron metabolism, Iron deficiency, Iron metabolism, Ferroportin, Hepcidin

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Background: Evidence shows that iron deficiency in adulthood may affect cognitive performance, possibly by disrupting neurotransmitter regulation or brain energy metabolism. Women of reproductive age (WRA) are among those who are most vulnerable to iron deficiency; however, they have been largely ignored in the literature relating iron status to cognition.Objective: Our aim was to determine the efficacy of iron-biofortified beans in improving cognition in WRA compared with control beans.Methods: A double-blind, randomized intervention study was conducted in 150 women aged 18-27 y with low iron status (ferritin <20 μg/L). Women were randomly assigned to consume iron-biofortified beans (86.1 ppm iron) or control beans (50.1 ppm iron) daily for 18 wk. Iron status was assessed based on hemoglobin, ferritin, transferrin receptor, and body iron values and on cognitive performance on 5 computerized tasks at baseline and endline.Results: Groups did not differ on any variables at baseline. Per protocol analyses revealed that consumption of the biofortified beans resulted in a 17% larger improvement in the speed of spatial selective attention; a nearly 7-fold larger improvement in the speed, a 68% greater improvement in the efficiency, and a >2-fold greater improvement in the specificity of memory retrieval; and a >2-fold larger improvement in the speed and a >3-fold larger improvement in the efficiency of memory search-all of which are relative to consumption of the control beans (P < 0.01 for all comparisons).Conclusions: Cognitive performance is sensitive to iron status, and consumption of iron-biofortified beans for 18 wk improved cognitive performance, especially the efficiency of search and the speed of retrieval on memory tasks, in young adult women. This trial was registered at clinicaltrials.gov as NCT01594359.

Concepts: Better, Hemoglobin, Psychology, Improve, Iron, Attention, Iron deficiency anemia, Transferrin

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Video capsule endoscopy (VCE) is being increasingly used to investigate small bowel pathology. It is the gold standard for obscure gastrointestinal bleeding and iron deficiency anemia. VCE has been in use since 2001 and indications for its use are expanding. VCE is also a useful diagnostic tool in small bowel Crohn’s disease, celiac disease, surveillance of polyps, small bowel malignancy and drug-induced small bowel injury. Although VCE is considered a safe and easy procedure, there are a few limitations. These include cost, capsule retention and inability to take a biopsy and perform any therapeutic maneuvers. Contraindications for VCE include pregnancy, patients with a swallowing disorder, history of previous abdominal surgery or concurrent abdomino-pelvic irradiation. This is an overview of VCE, its role and indications in clinical practice, potential complications and contraindications, as well as the ongoing and expected advances in the field.

Concepts: Medical terms, Crohn's disease, Colonoscopy, Gastroenterology, Small intestine, Bowel obstruction, Iron deficiency anemia, Malabsorption

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OBJECTIVE: To describe the prevalence of iron depletion (ID), iron-deficiency anaemia (IDA) and risk of haemoconcentration during pregnancy and at delivery and to assess the influence of initial Fe stores and Fe supplementation on that prevalence. DESIGN: Longitudinal study. SETTING: Hospital Universitari Sant Joan de Reus (Catalonia, Spain). SUBJECTS: Two hundred and eighty-five pregnant women. Serum ferritin and Hb were measured in the first, second and third trimesters and at delivery. Women were classified according to initial Fe stores as ID or no ID (serum ferritin ≥12 μg/l) and according to Fe supplement use as supplemented or non-supplemented. RESULTS: Initial ID was 16·2 %. At delivery, 45·7 % had ID, 13·5 % IDA and 13·3 % had risk of haemoconcentration. Initial ID and non-supplemented groups had significantly higher prevalences of ID and IDA and lower risk of haemoconcentration at delivery than the other groups. In the multiple logistic models, no initial ID and Fe supplementation exerted a protective effect against ID at delivery (adjusted OR = 0·28; 95 % CI 0·13, 0·58 and adjusted OR = 0·39; 95 % CI 0·22, 0·69, respectively). Moderate Fe supplementation did not seem to clearly prevent IDA (adjusted OR = 0·91; 95 % CI 0·42, 1·96) or to enhance the haemoconcentration (adjusted OR = 1·42; 95 % CI 0·58, 3·50). CONCLUSIONS: The prevalence of ID and IDA was high in late pregnancy in healthy pregnant women, particularly in those with initial ID and/or those not taking supplements. Starting pregnancy with no ID and/or taking moderate Fe supplementation decreased the likelihood of ID at delivery. The risk of haemoconcentration was high at delivery, but did not seem to be promoted by Fe supplementation. Further research is necessary to determine the most appropriate nutritional advice for pregnant women.

Concepts: Pregnancy, Childbirth, Iron, Folic acid, Iron deficiency anemia, Human iron metabolism, Iron supplements, Trimester

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BACKGROUND & AIMS: Celiac disease is an increasingly recognized disorder in Caucasian populations of European origin. Little is known about its prevalence in non-Caucasians. Although it is thought to be a cause of iron deficiency anemia, little is known about the extent to which celiac disease contributes to iron deficiency in Caucasians, and especially non-Caucasians. We analyzed samples collected from participants in the Hemochromatosis and Iron Overload Screening (HEIRS) study to identify individuals with iron deficiency and assess the frequency of celiac disease. METHODS: We analyzed serum samples from white men (25 y old or older) and women (50 y old or older) who participated the HEIRS study; cases were defined as individuals with iron deficiency (serum level of ferritin ≤12 mg/L) and controls were those without (serum level of ferritin >100 mg/L in men and >50 mg/L in women). All samples were also analyzed for human recombinant tissue transglutaminase immunoglobulin A; positive results were confirmed by an assay for endomysial antibodies. Patients with positive results from both celiac disease tests were presumed to have untreated celiac disease, and those with a positive result from only 1 test were excluded from analysis. We analyzed HLA genotypes and frequencies of celiac disease between Caucasians and non-Caucasians with iron deficiency. RESULTS: Celiac disease occurred in 14 of 567 of cases (2.5%) and in only 1 of 1136 controls (0.1%; Fisher’s exact test, P=1.92 10(-6)). Celiac disease was more common in Caucasian cases (14/363, 4%) than non-Caucasian cases (0/204; P=.003). Only 1 Caucasian control and no non-Caucasian controls had celiac disease. The odds of celiac disease in individuals with iron deficiency was 28-fold (95% confidence interval, 3.7-212.8) that of controls; 13/14 cases with celiac disease carried the DQ2.5 variant of the HLA genotype. CONCLUSIONS: Celiac disease is associated with iron deficiency of Caucasians. Celiac disease is rare among non-Caucasians-even among individuals with features of celiac disease, such as iron deficiency. Celiac disease is also rare among individuals without iron deficiency. Men and post-menopausal women with iron deficiency should be tested for celiac disease.

Concepts: Hemoglobin, Iron, Iron deficiency anemia, Coeliac disease, Transferrin, Human iron metabolism, Fisher's exact test, Exact test

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AIMS AND OBJECTIVES: To determine whether the use of a nurse-driven protocol in the haemodialysis setting is as safe and effective as traditional physician-driven approaches to anaemia management. BACKGROUND: The role of haemodialysis nurses in renal anaemia management has evolved through the implementation of nurse-driven protocols, addressing the trend of exceeding haemoglobin targets and rising costs of erythropoietin-stimulating agents. DESIGN: Retrospective, non-equivalent case control group design. METHODS: The sample was from three haemodialysis units in a control group (n = 64) and three haemodialysis units in a protocol group (n = 43). The protocol group used a nurse-driven renal anaemia management protocol, while the control group used a traditional physician-driven approach to renal anaemia management. All retrospective data were obtained from a provincial renal database. Data were analysed using chi-square tests and t-tests. Patient outcomes examined were haemoglobin levels, transferrin saturation levels, erythropoietin-stimulating agents use and intravenous iron use. Cost comparisons were determined using average use of erythropoietin-stimulating agents and intravenous iron. RESULTS: Control and protocol groups reached haemoglobin target levels. In the protocol group, 75% reached transferrin saturation target levels in comparison with 25% of the control group. Use and costs for iron was higher in the control group, while use and costs for erythropoietin was higher in the protocol group. The higher usage of erythropoietin-stimulating agents was potentially related to comorbid conditions amongst the protocol group. CONCLUSIONS: A nurse-driven protocol approach to renal anaemia management was as effective as the physician-driven approach in reaching haemoglobin and transferrin saturation levels. Further examination of the use and dosing of erythropoietin-stimulating agents and intravenous iron, their impact on haemoglobin levels related to patient comorbidities and subsequent cost effectiveness of protocols is required. RELEVANCE TO CLINICAL PRACTICE: Using a nurse-driven protocol in practice supports the independent nursing role while contributing to safe patient outcomes.

Concepts: Hemoglobin, Erythropoietin, Iron, Costs, Anemia, Iron deficiency anemia, Comorbidity, Transferrin saturation