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Anemia , Inhibidores de la Calcineurina/efectos adversos , Calcineurina , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Serina-Treonina Quinasas TOR , Aloinjertos , Anemia/sangre , Anemia/inducido químicamente , Anemia/genética , Calcineurina/genética , Calcineurina/metabolismo , Inhibidores de la Calcineurina/administración & dosificación , Femenino , Enfermedad Injerto contra Huésped/sangre , Enfermedad Injerto contra Huésped/tratamiento farmacológico , Enfermedad Injerto contra Huésped/genética , Humanos , Masculino , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/genéticaAsunto(s)
Anemia/genética , Eliptocitosis Hereditaria/genética , Glucosafosfato Deshidrogenasa/genética , Mutación , Piruvato Quinasa/genética , Anemia/diagnóstico , República Dominicana , Salud de la Familia , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Recién Nacido , Patrón de Herencia/genética , Masculino , Enfermedades Raras/diagnóstico , Enfermedades Raras/genética , Gemelos Monocigóticos/genéticaRESUMEN
Background: Iron deficiency anemia (IDA) is highly prevalent in women of child-bearing age. However, their nonhematological symptoms have been overlooked. This study aims to analyze the nonhematological features and symptoms of IDA in a group of women of reproductive age and the changes occurred during iron therapy. Materials and Methods: IDA women underwent dietary, physical activity, menstrual blood loss, and cognitive function assessment at baseline. Hematological and biochemical parameters were analyzed. Executive attention was tested by the flanker task and working memory by the 2-back task. Oral iron therapy (ferrous sulfate) was given to 35 women for 8 weeks and the changes in iron status, biochemical markers, cognitive function, and nonhematological symptoms were evaluated. Results: Patients presented nonhematological symptoms: pica, 32.4%; cheilitis, 20.6%; restless legs syndrome (RLS), 20.6%; diffuse hair loss, 55.9%; and ungual alterations, 38.2%. Two or more symptoms were present in 58.8% of women. Serum iron and working memory were correlated at baseline. Multivariate analyses show associations (odds ratio [OR], 95% confidence interval [CI]) between pica and reaction time in the working memory test (OR 2.14, 95% CI 1.19-3.87, p = 0.012); RLS with total serum protein (OR 0.08, 95% CI 0.06-0.92, p = 0.043); and cheilitis with mean corpuscular hemoglobin (OR 0.388, 95% CI 0.189-0.799, p = 0.01). Pica, cheilitis, and RLS completely resolved with iron therapy, and ungual alterations and hair loss improved in 92.3% and 84.2% of women, respectively. Better performance in executive attention and working memory was observed after iron therapy. Conclusions: More attention should be given to the nonhematological manifestations of IDA to improve the quality of life of menstruating women.
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We report a de novo aleukemic form of MCL with a complex monosomic karyotype with LOH for multiple chromosomes and TP53 mutation. Additionally, whereas D816V KIT was not found, the c-Kit transmembrane domain p.M541L variant was detected which is the most common SNP of KIT gene in humans with controversial pathogenic role. In these cases, it is crucial to perform a rapid broad molecular study for an accurate diagnosis which could help to initiate targeted therapy.
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Las enfermedades relacionadas con mutaciones del gen MYH9 son un grupo de patologías genéticas raras. Su herencia sigue un patrón autosómico dominante en donde el gen MYH9, codifica la cadena pesada de la miosina IIA no muscular que se expresa en diferentes tejidos pero especialmente en los podocitos y en las células mesangiales. Este trastorno se caracteriza por la presencia de macrotrombocitopenia, inclusiones leucocitarias y un riesgo variable de desarrollar insuficiencia renal, hipoacusia y cataratas en edad juvenil o adulta. Describimos el caso de una mujer de 27 años, de raza caucásica, diagnosticada inicialmente de púrpura trombocitopénica idiopática. Tras una detallada historia familiar y el desarrollo de síntomas clínicos posteriores con afectación renal e hipoacusia, se le realizó un estudio genético que nos permitió el diagnóstico de nefropatía asociada a la mutación en el gen MYH9. Este caso destaca el retraso del diagnóstico y la utilidad del estudio genético en pacientes con enfermedades muy poco frecuentes. Se procede a la revisión de la enfermedad en este artículo
MYH9 related diseases are caused by mutations in the MYH9 gene and constitute a rare group of genetic entities. Its inheritance follows an autosomal dominant pattern. The MYH9 gene, encodes the nonmuscle myosin heavy chain IIA, expressed in different tissues and especially in podocytes and mesangial cells. The disorder is characterized by the presence of macrothrombocytopenia, leukocyte inclusions and a variable risk of developing renal failure, hearing loss and early-onset cataracts. We describe the case of a 27-year-old Caucasian woman, diagnosed initially with idiopathic thrombocytopenic purpura. After a detailed family history and the appearance of renal involvement and hearing loss, genetic testing allowed to make the diagnosis of nephropathy associated with MYH9 mutation. This case is an example of the delayed diagnosis of uncommon diseases and highlights the usefulness genetic testing. A review of the disease is provided
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Humanos , Femenino , Adulto , Enfermedades Renales/genética , Mutación/genética , Nefritis Hereditaria/genética , Enfermedades Raras/genética , Pérdida Auditiva Súbita/complicaciones , Pérdida Auditiva Súbita/genética , Trombocitopenia/complicaciones , Trombocitopenia/genética , Diagnóstico DiferencialRESUMEN
MYH9 related diseases are caused by mutations in the MYH9 gene and constitute a rare group of genetic entities. Its inheritance follows an autosomal dominant pattern. The MYH9 gene, encodes the nonmuscle myosin heavy chain IIA, expressed in different tissues and especially in podocytes and mesangial cells. The disorder is characterized by the presence of macrothrombocytopenia, leukocyte inclusions and a variable risk of developing renal failure, hearing loss and early-onset cataracts. We describe the case of a 27-year-old Caucasian woman, diagnosed initially with idiopathic thrombocytopenic purpura. After a detailed family history and the appearance of renal involvement and hearing loss, genetic testing allowed to make the diagnosis of nephropathy associated with MYH9 mutation. This case is an example of the delayed diagnosis of uncommon diseases and highlights the usefulness genetic testing. A review of the disease is provided.
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Pérdida Auditiva Sensorineural/genética , Enfermedades Renales/genética , Cadenas Pesadas de Miosina/genética , Trombocitopenia/congénito , Adulto , Diagnóstico Tardío , Diagnóstico Diferencial , Femenino , Genotipo , Pérdida Auditiva Sensorineural/diagnóstico , Pérdida Auditiva Sensorineural/terapia , Humanos , Enfermedades Renales/diagnóstico , Enfermedades Renales/terapia , Mutación , Fenotipo , Púrpura Trombocitopénica Idiopática/diagnóstico , Trombocitopenia/diagnóstico , Trombocitopenia/genética , Trombocitopenia/terapiaAsunto(s)
Eritrocitos/metabolismo , Predisposición Genética a la Enfermedad , Trombosis , Tromboembolia Venosa , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Eritrocitos/patología , Femenino , Haptoglobinas/genética , Haptoglobinas/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Linaje , Receptores de Transferrina/sangre , Receptores de Transferrina/genética , Trombosis/sangre , Trombosis/genética , Tromboembolia Venosa/sangreRESUMEN
Numerous studies associate genetic markers with iron- and erythrocyte-related parameters, but few relate them to iron-clinical phenotypes. Novel SNP rs1375515, located in a subunit of the calcium channel gene CACNA2D3, is associated with a higher risk of anaemia. The aim of this study is to further investigate the association of this SNP with iron-related parameters and iron-clinical phenotypes, and to explore the potential role of calcium channel subunit region in iron regulation. Furthermore, we aim to replicate the association of other SNPs reported previously in our population. We tested 45 SNPs selected via systematic review and fine mapping of CACNA2D3 region, with haematological and biochemical traits in 358 women of reproductive age. Multivariate analyses include back-step logistic regression and decision trees. The results replicate the association of SNPs with iron-related traits, and also confirm the protective effect of both A allele of rs1800562 (HFE) and G allele of rs4895441 (HBS1L-MYB). The risk of developing anaemia is increased in reproductive age women carriers of A allele of rs1868505 (CACNA2D3) and/or T allele of rs13194491 (HIST1H2BJ). Association of SNPs from fine mapping with ferritin and serum iron suggests that calcium channels could be a potential pathway for iron uptake in physiological conditions.
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Anemia Ferropénica/genética , Anemia Ferropénica/metabolismo , Canales de Calcio/genética , Predisposición Genética a la Enfermedad , Hierro/metabolismo , Polimorfismo de Nucleótido Simple , Subunidades de Proteína/genética , Adolescente , Adulto , Alelos , Anemia Ferropénica/sangre , Canales de Calcio/química , Índices de Eritrocitos , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Persona de Mediana Edad , Fenotipo , Adulto JovenRESUMEN
INTRODUCTION: Platelets play a significant role in arterial thrombosis and are involved also in venous thrombosis. The genetic determinants of several platelet-related phenotypes have been studied previously. However, to the best of our knowledge, the genetic determinants of other platelet phenotypes have not been reported such as platelet-large-cell ratio (P-LCR) index, immature platelet fraction (IPF) parameters and overall platelet function measured through the PFA-100 system. MATERIALS AND METHODS: As part of the GAIT-2 (Genetic Analysis of Idiopathic Thrombophilia 2) Project, 935 individuals from 35 large Spanish families, ascertained through a proband with thrombophilia, were studied. Using variance component methods, implemented in the SOLAR package, the heritability of the following sets of platelet-related phenotypes was determined: platelet count and indices, IPF, and platelet function. RESULTS AND CONCLUSIONS: High heritabilities of the platelet count and index phenotypes (from 0.41 to 0.64) were found, especially for those related to platelet volume. The heritabilities of the IPF phenotypes, as a measure of platelet turnover, were the highest (from 0.65 to 0.69). The heritabilities of the platelet function phenotypes were high also (0.45 and 0.62). The covariate age influenced all of the platelet phenotypes. Smoking influenced the platelet indices related to platelet volume and all the IPF phenotypes. Venous thrombosis showed a heritability of 0.67. We did not find a genetic correlation between any of the platelet-related phenotypes and venous thrombosis. The high heritabilities found for all of the platelet phenotypes provid promising data for the identification of new genes that underly these phenotypes.
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Plaquetas/clasificación , Predisposición Genética a la Enfermedad/genética , Volúmen Plaquetario Medio/estadística & datos numéricos , Recuento de Plaquetas/estadística & datos numéricos , Trombofilia/sangre , Trombofilia/genética , Adolescente , Adulto , Plaquetas/patología , Femenino , Estudios de Asociación Genética/estadística & datos numéricos , Predisposición Genética a la Enfermedad/epidemiología , Humanos , Masculino , Prevalencia , España/epidemiología , Trombofilia/epidemiología , Adulto JovenRESUMEN
This study aimed to evaluate the evolution of iron overload, assessed by serum ferritin (SF), in transfusion-dependent lower risk patients with myelodysplastic syndrome (MDS), as well as to describe the occurrence of organ complications, and to analyze its relationship with iron chelation therapy. This observational retrospective study was conducted from March 2010 to March 2011 in 47 Spanish hospitals. A total of 263 patients with lower risk MDS (International Prognostic Scoring System [IPSS] low/intermediate-1 risk or Spanish Prognostic Index [SPI] 0-1 risk), transfusion-dependent, and who had received ≥10 packed red blood cells (PRBC) were included. At MDS diagnosis, patients received a mean of 2.8 ± 3.9 PRBC/month, and 8.7% of patients showed SF ≥1000 µg/L. Over the course of the disease, patients received a mean of 83.4 ± 83.3 PRBC, and 36.1% of patients presented SF ≥2500 µg/L. Cardiac, hepatic, endocrine, or arthropathy complications appeared/worsened in 20.2, 11.4, 9.9, and 3.8% of patients, respectively. According to investigator, iron overload was a main cause of hepatic (70.0%) and endocrine (26.9%) complications. A total of 96 (36.5%) patients received iron chelation therapy for ≥6 months, being deferasirox the most frequent first chelation treatment (71.9%). Chelation-treated patients showed longer overall survival (p < 0.001), leukemia-free survival (p = 0.007), and cardiac event-free survival (p = 0.017) than non-chelated patients. In multivariable analyses, age (p = 0.011), IPSS (p < 0.001), and chelation treatment (p = 0.015) were predictors for overall survival; IPSS (p = 0.014) and transfusion frequency (p = 0.001) for leukemia-free survival; and chelation treatment (p = 0.040) and Sorror comorbidity index (p = 0.039) for cardiac event-free survival. In conclusion, these results confirm the potential survival benefit of iron chelation therapy and provide additional evidence on the deleterious effect of iron overload in lower risk MDS patients.
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Terapia por Quelación/métodos , Sobrecarga de Hierro/tratamiento farmacológico , Síndromes Mielodisplásicos/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Femenino , Ferritinas/sangre , Humanos , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/mortalidad , Masculino , Persona de Mediana Edad , Síndromes Mielodisplásicos/sangre , Síndromes Mielodisplásicos/mortalidad , Estudios RetrospectivosRESUMEN
Iron-deficiency anaemia (IDA), one of the most common and widespread health disorders worldwide, affects fundamental metabolic functions and has been associated with deleterious effects on bone. Our aim was to know whether there are differences in bone remodelling between a group of premenopausal IDA women and a healthy group, and whether recovery of iron status has an effect on bone turnover markers. Thirty-five IDA women and 38 healthy women (control group) were recruited throughout the year. IDA women received pharmacological iron treatment. Iron biomarkers, aminoterminal telopeptide of collagen I (NTx), procollagen type 1 N-terminal propeptide (P1NP), 25-hydroxyvitamin D, and parathormone (PTH) were determined at baseline for both groups and after treatment with pharmacological iron for the IDA group. IDA subjects were classified as recovered (R) or non-recovered (nR) from IDA after treatment. NTx levels were significantly higher (p <0.001), and P1NP levels tended to be lower in IDA women than controls after adjusting for age and body mass index (BMI), with no differences in 25-hydroxyvitamin D or PTH. After treatment, the R group had significantly lower NTx and P1NP levels compared to baseline (p <0.05 and p <0.001 respectively), whilst no significant changes were seen in the nR group. No changes were seen in 25-hydroxyvitamin D or PTH for either group. IDA is related to higher bone resorption independent of age and BMI. Recovery from IDA has a concomitant beneficial effect on bone remodelling in premenopausal women, decreasing both bone resorption and formation (AU)
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Humanos , Femenino , Persona de Mediana Edad , Remodelación Ósea , 16595/complicaciones , Anemia Ferropénica/fisiopatología , Premenopausia/fisiología , Estudios de Casos y Controles , Hierro/uso terapéuticoRESUMEN
Iron-deficiency anaemia (IDA), one of the most common and widespread health disorders worldwide, affects fundamental metabolic functions and has been associated with deleterious effects on bone. Our aim was to know whether there are differences in bone remodelling between a group of premenopausal IDA women and a healthy group, and whether recovery of iron status has an effect on bone turnover markers. Thirty-five IDA women and 38 healthy women (control group) were recruited throughout the year. IDA women received pharmacological iron treatment. Iron biomarkers, aminoterminal telopeptide of collagen I (NTx), procollagen type 1 N-terminal propeptide (P1NP), 25-hydroxyvitamin D, and parathormone (PTH) were determined at baseline for both groups and after treatment with pharmacological iron for the IDA group. IDA subjects were classified as recovered (R) or non-recovered (nR) from IDA after treatment. NTx levels were significantly higher (p <0.001), and P1NP levels tended to be lower in IDA women than controls after adjusting for age and body mass index (BMI), with no differences in 25-hydroxyvitamin D or PTH. After treatment, the R group had significantly lower NTx and P1NP levels compared to baseline (p <0.05 and p <0.001 respectively), whilst no significant changes were seen in the nR group. No changes were seen in 25-hydroxyvitamin D or PTH for either group. IDA is related to higher bone resorption independent of age and BMI. Recovery from IDA has a concomitant beneficial effect on bone remodelling in premenopausal women, decreasing both bone resorption and formation.
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Anemia Ferropénica/tratamiento farmacológico , Resorción Ósea/tratamiento farmacológico , Compuestos Ferrosos/uso terapéutico , Hematínicos/uso terapéutico , Hierro/metabolismo , Premenopausia , Adolescente , Adulto , Anemia Ferropénica/sangre , Anemia Ferropénica/patología , Anemia Ferropénica/orina , Biomarcadores/sangre , Biomarcadores/orina , Resorción Ósea/sangre , Resorción Ósea/patología , Resorción Ósea/orina , Estudios de Casos y Controles , Colágeno Tipo I/orina , Femenino , Humanos , Hormona Paratiroidea/sangre , Fragmentos de Péptidos/sangre , Péptidos/orina , Procolágeno/sangre , Vitamina D/análogos & derivados , Vitamina D/sangreAsunto(s)
Candida , Candidiasis/sangre , Candidiasis/patología , Complicaciones Posoperatorias/sangre , Antiinfecciosos/administración & dosificación , Proteína C-Reactiva/metabolismo , Candidiasis/tratamiento farmacológico , Candidiasis/etiología , Enterococcus faecium , Escherichia coli , Infecciones por Escherichia coli/sangre , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/etiología , Infecciones por Bacterias Grampositivas/sangre , Infecciones por Bacterias Grampositivas/tratamiento farmacológico , Infecciones por Bacterias Grampositivas/etiología , Enfermedad de Hirschsprung/cirugía , Humanos , Lactante , Masculino , Neutrófilos/microbiología , Neutrófilos/patología , Complicaciones Posoperatorias/tratamiento farmacológico , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/microbiologíaRESUMEN
Macrocytosis, the hallmark of cobalamin/folate deficiency anemia, is frequently absent. Clinicians have to be aware of coexisting conditions that can mask the macrocytosis expression of megaloblastic anemia, especially iron deficiency. The objective of this work was to investigate the degree of overlap between iron deficiency anemia (IDA) and cobalamin deficiency and to develop a predictive model for differentiating IDA from combined deficiency. A prospective case and control study was carried out to investigate vitamin B12 and folate status in iron deficiency anemia. A total of 658 patients were recruited, 41 of whom (6.2 %) were excluded. The remaining 617 subjects consisted of 130 controls and 487 with IDA. Low vitamin B12 (LB12) was considered when serum vitamin B12 was ≤200 pmol/L. High serum homocysteine (Hcy) was defined by Hcy >17 µM/L. A multivariate analysis (including a logistic regression) was performed to develop a diagnostic model. Low vitamin B12 levels were found in 17.8 % of IDA subjects. Ten out of 11 subjects (91 %) with IDA and serum vitamin B12 (B12) ≤100 pmol/L showed vitamin B12 deficiency. Moreover, vitamin B12 deficiency was demonstrated in 48 % of cases with IDA and B12 between 101 and 150 pmol/L and in 40 % with IDA and B12 between 151 and 200 pmol/, respectively. As a result of multivariate logistic analysis, neutrophil counts and age predicted subjects with vitamin B12 ≤200 and Hcy >17 µmol/L, [Formula: see text]. Using the age of 60 as a cutoff, sensitivity was 91 % (39 out of the 43 patients with vitamin B12 deficiency and IDA were identified). In summary, low vitamin B12 was found in 18 % of patients with IDA. Vitamin B12 deficiency was demonstrated in many patients with LB12 and IDA. Age over 60 years was used to separate patients with combined deficiency (sensitivity 91 %). Therefore, for a diagnostic purpose, serum vitamin B12 should be evaluated in IDA patients over 60 years. This diagnostic model needs to be validated in a different population.
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Anemia Ferropénica/complicaciones , Anemia Ferropénica/diagnóstico , Técnicas y Procedimientos Diagnósticos , Homocisteína/análisis , Deficiencia de Vitamina B 12/complicaciones , Deficiencia de Vitamina B 12/diagnóstico , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Anemia Ferropénica/sangre , Estudios de Casos y Controles , Técnicas de Apoyo para la Decisión , Femenino , Hematología/métodos , Homocisteína/sangre , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Sensibilidad y Especificidad , Vitamina B 12/análisis , Vitamina B 12/sangre , Deficiencia de Vitamina B 12/sangreRESUMEN
This study aimed at assessing the relationship between thrombosis, hyperhomocysteinemia and vitamin B12 deficiency using a case-control study carried out in 326 patients with thrombosis (case group) and 351 patients from the same hospital (control group). Apart from the classic risk factors, a number of hematological variables were evaluated, including serum vitamin B12 (B12), red cell folate (RCF), and serum homocysteine (Hcy). An evaluation of serum methylmalonic acid (MMA) and a clinical study were carried out to investigate B12 pathology. Results of univariate analysis demonstrated decreased B12 levels in thrombosis (Student's t test, p < 0.0001). Vitamin B12 below 200 pmol/l (LB200) or below 150 pmol/l (LB150), and red cell folate below 600 nmol/l were found in 17.2, 8.6, and 2.2% of cases with thromboembolism, respectively. An increase in Hcy was detected in 86 cases with thrombosis (26.3%). An abnormality in vitamin B12 and/or renal function was found in 80% of cases with hyperHcy and thrombosis. The MMA increase demonstrated that vitamin B12 deficiency was present in these patients with low levels of vitamin B12 in serum, and the MMA levels were in concordance with Hcy levels. The clinical study revealed B12 malabsorption in most cases with LB200. Multivariate analysis showed that serum vitamin B12 (RR 0.998, CI 0.997-0.999) was moderately related to thromboembolism. The results indicated that vitamin B12 deficiency was common among patients with hyperhomocysteinemia and thrombosis. Moreover, HyperHcy was caused by vitamin B12 deficiency and/or chronic renal failure in most patients with thrombosis. As the main cause of vitamin B12 deficiency was vitamin malabsorption, parenteral vitamin B12 with or without folic acid should be administered for the treatment of this condition. However, it remains to be demonstrated whether this treatment approach prevents recurrent thromboses in patients with vitamin B12 deficiency and thrombosis, as suggested by some case reports.
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Hiperhomocisteinemia/complicaciones , Trombosis/complicaciones , Deficiencia de Vitamina B 12/complicaciones , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Ácido Fólico/sangre , Homocisteína/sangre , Humanos , Hiperhomocisteinemia/sangre , Masculino , Ácido Metilmalónico/sangre , Persona de Mediana Edad , Trombosis/sangre , Vitamina B 12/sangre , Deficiencia de Vitamina B 12/sangreRESUMEN
IRON FUNCTIONS: Iron is an essential micronutrient, as it is required for satisfactory erythropoietic function, oxidative metabolism and cellular immune response. IRON PHYSIOLOGY: Absorption of dietary iron (1-2 mg/day) is tightly regulated and just balanced against iron loss because there are no active iron excretory mechanisms. Dietary iron is found in haem (10%) and non-haem (ionic, 90%) forms, and their absorption occurs at the apical surface of duodenal enterocytes via different mechanisms. Iron is exported by ferroportin 1 (the only putative iron exporter) across the basolateral membrane of the enterocyte into the circulation (absorbed iron), where it binds to transferrin and is transported to sites of use and storage. Transferrin-bound iron enters target cells-mainly erythroid cells, but also immune and hepatic cells-via receptor-mediated endocytosis. Senescent erythrocytes are phagocytosed by reticuloendothelial system macrophages, haem is metabolised by haem oxygenase, and the released iron is stored as ferritin. Iron will be later exported from macrophages to transferrin. This internal turnover of iron is essential to meet the requirements of erythropoiesis (20-30 mg/day). As transferrin becomes saturated in iron-overload states, excess iron is transported to the liver, the other main storage organ for iron, carrying the risk of free radical formation and tissue damage. REGULATION OF IRON HOMOEOSTASIS: Hepcidin, synthesised by hepatocytes in response to iron concentrations, inflammation, hypoxia and erythropoiesis, is the main iron-regulatory hormone. It binds ferroportin on enterocytes, macrophages and hepatocytes triggering its internalisation and lysosomal degradation. Inappropriate hepcidin secretion may lead to either iron deficiency or iron overload.
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Homeostasis/fisiología , Hierro/metabolismo , Animales , Péptidos Catiónicos Antimicrobianos/fisiología , Eritropoyesis/fisiología , Hepcidinas , Humanos , Inflamación/metabolismo , Absorción Intestinal/fisiología , Transducción de Señal/fisiologíaRESUMEN
MAIN DISORDERS OF IRON METABOLISM: Increased iron requirements, limited external supply, and increased blood loss may lead to iron deficiency (ID) and iron deficiency anaemia. In chronic inflammation, the excess of hepcidin decreases iron absorption and prevents iron recycling, resulting in hypoferraemia and iron restricted erythropoiesis, despite normal iron stores (functional iron deficiency), and finally anaemia of chronic disease (ACD), which can evolve to ACD plus true ID (ACD+ID). In contrast, low hepcidin expression may lead to hereditary haemochromatosis (HH type I, mutations of the HFE gene) and type II (mutations of the hemojuvelin and hepcidin genes). Mutations of transferrin receptor 2 lead to HH type III, whereas those of the ferroportin gene lead to HH type IV. All these syndromes are characterised by iron overload. As transferrin becomes saturated in iron overload states, non-transferrin bound iron appears. Part of this iron is highly reactive (labile plasma iron), inducing free radical formation. Free radicals are responsible for the parenchymal cell injury associated with iron overload syndromes. ROLE OF LABORATORY TESTING IN DIAGNOSIS: In iron deficiency status, laboratory tests may provide evidence of iron depletion in the body or reflect iron deficient red cell production. Increased transferrin saturation and/or ferritin levels are the main cues for further investigation of iron overload. The appropriate combination of different laboratory tests with an integrated algorithm will help to establish a correct diagnosis of iron overload, iron deficiency and anaemia. REVIEW OF TREATMENT OPTIONS: Indications, advantages and side effects of the different options for treating iron overload (phlebotomy and iron chelators) and iron deficiency (oral or intravenous iron formulations) will be discussed.