Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 25
Filtrar
1.
Ann Hepatol ; 16(5): 802-811, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28809726

RESUMEN

BACKGROUND: 373 black participants had elevated screening and post-screening serum ferritin (SF) (> 300 µg/L men; > 200 µg/L women). MATERIAL AND METHODS: We retrospectively studied SF and post-screening age; sex; body mass index; transferrin saturation (TS); ALT; AST; GGT; elevated C-reactive protein; ß-thalassemia; neutrophils; lymphocytes; monocytes; platelets; metacarpophalangeal joint hypertrophy; hepatomegaly; splenomegaly; diabetes; HFE H63D positivity; iron/alcohol intakes; and blood/erythrocyte transfusion units. Liver disease was defined as elevated ALT or AST. We computed correlations of SF and TS with: age; body mass index; ALT; AST; GGT; C-reactive protein; blood cell counts; and iron/alcohol. We compared participants with SF > 1,000 and ≤ 1,000 µg/L and performed regressions on SF. RESULTS: There were 237 men (63.5%). Mean age was 55 ± 13 (SD) y. 143 participants had liver disease (62 hepatitis B or C). There were significant correlations of SF: TS, ALT, AST, GGT, and monocytes (positive); and SF and TS with platelets (negative). 22 participants with SF > 1,000 µg/L had significantly higher median TS, ALT, and AST, and prevalences of anemia and transfusion > 10 units; and lower median platelets. Regression on SF revealed significant associations: TS; male sex; age; GGT; transfusion units (positive); and splenomegaly (negative) (p < 0.0001, 0.0016, 0.0281, 0.0025, 0.0001, and 0.0096, respectively). Five men with SF > 1,000 µg/L and elevated TS had presumed primary iron overload (hemochromatosis). Four participants had transfusion iron overload. CONCLUSION: Persistent hyperferritinemia in 373 black adults was associated with male sex, age, TS, GGT, and transfusion. 2.4% had primary iron overload (hemochromatosis) or transfusion iron overload.


Asunto(s)
Ferritinas/sangre , Hemocromatosis/sangre , Sobrecarga de Hierro/sangre , Adulto , Negro o Afroamericano/genética , Anciano , Alabama/epidemiología , Biomarcadores/sangre , Transfusión Sanguínea , Comorbilidad , Femenino , Hemocromatosis/etnología , Hemocromatosis/genética , Hemocromatosis/terapia , Humanos , Sobrecarga de Hierro/etnología , Sobrecarga de Hierro/genética , Sobrecarga de Hierro/terapia , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Factores Sexuales , Transferrina/metabolismo , Resultado del Tratamiento , Regulación hacia Arriba , gamma-Glutamiltransferasa/sangre
2.
Am J Med Sci ; 349(1): 50-5, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25559280

RESUMEN

BACKGROUND: Primary iron overload in African Americans has been reported predominantly from autopsy studies. METHODS: We characterized hepatic iron phenotypes in 83 African Americans who underwent liver biopsy during the interval 1990 to 1995. We tabulated pathology report form data, iron grades in hepatocytes (0-4) and Kupffer cells (0-3) and abnormal liver histology. Increased iron was defined as hepatocyte or Kupffer iron grades ≥ 2, respectively. Heavy iron was defined as hepatocyte iron grade 3 or 4. Primary iron overload was defined as the presence of grade 3 or 4 hepatocellular iron in the absence of evidence of chronic alcohol effect, viral hepatitis, steatosis, unexplained inflammation, chronic erythrocyte transfusion or chronic ingestion of iron supplements. RESULTS: There were 37 men and 46 women (mean age: 53 ± 15 [SD] years). We observed heavy ethanol consumption, 12.0%; viral hepatitis, 26.5%; steatosis without heavy ethanol consumption, 43.4%; inflammation, 45.6%; fibrosis, 26.2% and bridging fibrosis/cirrhosis, 29.4%. Logistic regression on bridging fibrosis/cirrhosis revealed positive associations with heavy ethanol consumption (P = 0.0410) and viral hepatitis (P = 0.0044). The 22 patients (26.5%) with increased iron had greater mean age, proportion of men and heavy ethanol consumption. Five patients had heavy iron staining, among whom were 3 women (mean age: 54 years) with primary iron overload. Two of the 3 women had cirrhosis and diabetes mellitus. CONCLUSIONS: Among 83 adult African Americans who underwent liver biopsy, 3.6% had hepatic iron phenotypes consistent with primary iron overload.


Asunto(s)
Negro o Afroamericano , Sobrecarga de Hierro , Hierro/metabolismo , Hepatopatías , Hígado/metabolismo , Anciano , Consumo de Bebidas Alcohólicas/epidemiología , Consumo de Bebidas Alcohólicas/etnología , Consumo de Bebidas Alcohólicas/metabolismo , Biopsia , Femenino , Hepatocitos/metabolismo , Humanos , Sobrecarga de Hierro/epidemiología , Sobrecarga de Hierro/etnología , Sobrecarga de Hierro/metabolismo , Sobrecarga de Hierro/patología , Macrófagos del Hígado/metabolismo , Hígado/patología , Hepatopatías/epidemiología , Hepatopatías/etnología , Hepatopatías/metabolismo , Hepatopatías/patología , Masculino , Persona de Mediana Edad
3.
J Clin Rheumatol ; 19(6): 324-8, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23965472

RESUMEN

OBJECTIVE: A markedly elevated serum ferritin level has been associated with inflammatory conditions such as adult-onset Still's disease, systemic juvenile idiopathic arthritis, and hemophagocytic lymphohistiocytosis/macrophage activation syndrome. Hyperferritinemia, however, can also be caused by a wide variety of disparate conditions, often with impressively high serum levels. The objective of this analysis was to investigate the underlying etiology of markedly elevated ferritin levels in a large group of patients treated as outpatients and inpatients in a tertiary-care medical center. METHODS: Data of all adult patients from 2008 through 2010 with at least 1 serum ferritin level greater than 1000 µg/L were reviewed. If a patient had multiple qualifying levels, the highest one was used. For each case, the most likely cause of the elevated ferritin was assessed based on the available clinical data using a simple algorithmic approach. RESULTS: Six hundred twenty-seven patients were found. The average serum ferritin level was 2647 µg/L. The most frequent condition was malignancy (153/627), with iron-overload syndromes the second most common (136/627). There were 6 cases of adult-onset Still's disease, systemic juvenile idiopathic arthritis, or hemophagocytic lymphohistiocytosis/macrophage activation syndrome. The average ferritin level in these syndromes was 14242 µg/L. Seven patients appeared to have anemia of chronic inflammation, and in 5 patients, there was no clearly definable cause for hyperferritinemia. CONCLUSIONS: Although extremely elevated ferritin levels may be associated with rheumatologic diseases, more often they are found in patients with other conditions such as malignancy or infection. In addition, extremely high ferritin levels can be found in patients with seemingly indolent disease or levels of chronic inflammation.


Asunto(s)
Artritis Juvenil/complicaciones , Ferritinas/sangre , Sobrecarga de Hierro/complicaciones , Linfohistiocitosis Hemofagocítica/complicaciones , Neoplasias/complicaciones , Enfermedad de Still del Adulto/complicaciones , Centros Médicos Académicos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Artritis Juvenil/sangre , Artritis Juvenil/etnología , Asiático , Población Negra , Femenino , Hispánicos o Latinos , Humanos , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/etnología , Linfohistiocitosis Hemofagocítica/sangre , Linfohistiocitosis Hemofagocítica/etnología , Masculino , Persona de Mediana Edad , Neoplasias/sangre , Neoplasias/etnología , Estudios Retrospectivos , Enfermedad de Still del Adulto/sangre , Enfermedad de Still del Adulto/etnología , Tennessee , Población Blanca , Adulto Joven
4.
Eur J Gastroenterol Hepatol ; 25(1): 94-8, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23085575

RESUMEN

BACKGROUND/AIM: Peripheral intrahepatic cholangiocarcinoma (ICC) occurring mainly in the absence of cirrhosis represents an increasing subgroup of primary liver tumors in Western countries. Histopathologic changes in the non-neoplastic liver in this context are not well characterized. PATIENTS AND METHODS: We assessed the clinical characteristics and histopathologic changes in the distant nontumoral liver of 57 consecutive White patients (34 men, mean age 59 years) referred to one medical and one surgical liver institution over a 16-year period who developed a peripheral ICC in the absence of cirrhosis or bile duct disease. RESULTS: High alcohol consumption was observed in 11 patients (20%), 38 patients (66%) had a BMI of 25 kg/m or more, 22 patients (40%) had diabetes, two patients had hepatitis B virus infection, two others had hepatitis C virus infection, three patients had genetic hemochromatosis, and two patients had cutaneous porphyria tarda. The distant nontumoral liver was normal in 10 patients (18%). The two main histopathologic changes observed were macrovesicular steatosis (>10% of hepatocytes) in 38 patients (66%), including 11 patients (19%) with steatohepatitis, and moderate or intense hepatocyte iron overload in 22 patients (38%). CONCLUSION: This study shows a high prevalence of macrovesicular steatosis associated or not with steatohepatitis and iron overload in patients who develop peripheral ICC in the absence of cirrhosis or bile duct disease.


Asunto(s)
Colangiocarcinoma/etnología , Colangiocarcinoma/patología , Neoplasias Hepáticas/etnología , Neoplasias Hepáticas/patología , Hígado/patología , Población Blanca , Anciano , Neoplasias de los Conductos Biliares , Conductos Biliares Intrahepáticos , Biopsia , Hígado Graso/etnología , Hígado Graso/patología , Hígado Graso Alcohólico/etnología , Hígado Graso Alcohólico/patología , Femenino , Francia/epidemiología , Humanos , Sobrecarga de Hierro/etnología , Sobrecarga de Hierro/patología , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico , Prevalencia , Estudios Retrospectivos , Factores de Riesgo , Factores de Tiempo
5.
J Nutr ; 142(4): 764-70, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22378332

RESUMEN

Accelerated loss of traditional lifestyles may place Inuit at risk of iron depletion given that anemia has been observed among Arctic men. The objectives of this study were to determine the prevalence of anemia, storage iron depletion, and iron overload and to identify correlates of iron status in Canadian Inuit men. In a cross-sectional survey of 994 men in the International Polar Year Inuit Health Survey, 2007-2008, hemoglobin, serum ferritin (SF), soluble transferrin receptor (on a subset), CRP, RBC fatty acid composition, and Helicobacter pylori serology were measured in venous blood drawn from fasting men. Anthropometric, dietary, sociodemographic, and health data were collected. Dietary and nondietary correlates of iron status were assessed with multiple linear and logistic models. For men with CRP ≤10 mg/L (n = 804), 6.5% had depleted, 19.8% had low, and 10.3% had elevated iron stores. Anemia was moderately prevalent (16.1%), but iron deficiency anemia was less common (2.4%). There was a low probability of dietary iron inadequacy (2.4% < Estimated Average Requirement) and excess iron intakes (10.7% > Tolerable Upper Intake Level). Food-insecure men and those without a household hunter had a higher risk of low or depleted iron stores. Adiposity, traditional food intake, long-chain RBC PUFA status, and inflammation were positively associated with SF and food insecurity, smoking, and H. pylori seropositivity were negatively associated with SF. Despite a moderate prevalence of anemia, iron stores are largely adequate in this population, although lower than expected based on iron intake. The regulation of iron metabolism in this population and the high prevalence of anemia in older men warrants further investigation.


Asunto(s)
Dieta/efectos adversos , Inuk , Hierro/administración & dosificación , Estado Nutricional/etnología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anemia Ferropénica/epidemiología , Anemia Ferropénica/etnología , Anemia Ferropénica/etiología , Anemia Ferropénica/fisiopatología , Regiones Árticas/epidemiología , Proteína C-Reactiva/análisis , Canadá/epidemiología , Estudios Transversales , Dieta/etnología , Ferritinas/sangre , Hemoglobinas/análisis , Humanos , Hierro/efectos adversos , Deficiencias de Hierro , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/epidemiología , Sobrecarga de Hierro/etnología , Sobrecarga de Hierro/etiología , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Prevalencia , Receptores de Transferrina/sangre , Receptores de Transferrina/química , Índice de Severidad de la Enfermedad , Adulto Joven
6.
Vestn Ross Akad Med Nauk ; (9): 44-8, 2011.
Artículo en Ruso | MEDLINE | ID: mdl-22145371

RESUMEN

Human HFE gene haplotype analysis with reference to IVS2(+4)t/c, IVS4(-44)t/c, IVS5(-47)a/g polymorphic sites was performed in different North Asian ethnic groups. Of the eight possible intronic haplotypes, TTG, TTA, CTA and CCA were identified. High frequency of the CCA haplotype appears to be a characteristic feature of all Asian native populations. Potential functional importance of IVS4(-44)t/c polymorphism is demonstrated. Patients presenting with iron overload syndrome are shown to have low frequency of IVS4(-44)c.


Asunto(s)
Proyecto Mapa de Haplotipos , Antígenos de Histocompatibilidad Clase I/genética , Sobrecarga de Hierro/etnología , Sobrecarga de Hierro/genética , Proteínas de la Membrana/genética , Polimorfismo Genético , Pueblo Asiatico/genética , Proteína de la Hemocromatosis , Humanos , Intrones , Hierro/metabolismo , Sobrecarga de Hierro/metabolismo , Redes y Vías Metabólicas/genética , Siberia
7.
Blood Cells Mol Dis ; 42(2): 150-4, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19176287

RESUMEN

Heme carrier protein 1 (HCP1) has been identified as a possible heme carrier by in vitro analysis. To determine the association of mutations within the HCP1 gene with iron phenotypes, we examined the entire coding region of the HCP1 gene in 788 US and Canadian participants selected from the Hemochromatosis and Iron Overload Screening (HEIRS) Study using denaturing high-performance liquid chromatography. We sequenced the exon and flanking intronic regions if variants were detected. We tested 298 non-C282Y homozygotes from four racial/ethnic backgrounds (White, Black, Asian, and Hispanic) selected because they had high serum ferritin (SF) and transferrin saturations (TS). As controls, we chose 300 other random participants of the same racial/ethnic backgrounds from the same geographic locations. From the 333 HEIRS Study C282Y homozygotes, we selected 75 based on high SF and TS, 75 based on low SF and TS; and 75 were selected randomly as controls. Thirty-five of the randomly selected C282Y homozygotes were also included in the high and the low SF and TS groups due to numerical limitations. We identified eight different HCP1 genetic variants; each occurred in a heterozygous state. Except one, each was found in a single HEIRS Study participant. Thus, HCP1 variants are infrequent in the populations that we tested. Five HEIRS Study participants had non-synonymous, coding region HCP1 variants. Each of these five had TS above the 84th gender- and ethnic/racial group-specific percentile (TS percentiles: 84.7, 91.3, 97.9, 99.5, and 99.9).


Asunto(s)
Hemocromatosis/genética , Sobrecarga de Hierro/genética , Proteínas de Transporte de Membrana/genética , Canadá/epidemiología , Estudios de Casos y Controles , Cromatografía Líquida de Alta Presión , Estudios de Cohortes , Análisis Mutacional de ADN , Etnicidad/genética , Exones/genética , Hemocromatosis/sangre , Hemocromatosis/etnología , Proteína de la Hemocromatosis , Heterocigoto , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Intrones/genética , Hierro/sangre , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/etnología , Proteínas de la Membrana/genética , Proteínas de Transporte de Membrana/fisiología , Mutación Missense , Desnaturalización de Ácido Nucleico , Mutación Puntual , Transportador de Folato Acoplado a Protón , Grupos Raciales/genética , Muestreo , Transferrina/análisis , Estados Unidos/epidemiología
8.
Am J Hematol ; 83(8): 618-26, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18429050

RESUMEN

How often elevated serum ferritin in primary-care patients reflects increased iron stores (normally 0.8 g in men, 0.4 g in women) is not known. The Hereditary Hemochromatosis and Iron Overload Screening (HEIRS) study screened 101,168 primary-care participants (44% Caucasians, 27% African-Americans, 14% Asians/Pacific Islanders, 13% Hispanics, 2% others). Follow-up clinical evaluation was performed in 302 of 333 HFE C282Y homozygotes regardless of iron measures and 1,375 of 1,920 nonhomozygotes with serum ferritin >300 microg/L (men), >200 microg/L (women) and transferrin saturation >50% (men), >45% (women). Quantitative phlebotomy was conducted in 122 of 175 C282Y homozygotes and 122 of 1,102 nonhomozygotes with non-transfusional serum ferritin elevation at evaluation. The estimated prevalence in the Caucasian population of C282Y homozygotes with serum ferritin >900 microg/L at evaluation was 20 per 10,000 men and 4 per 10,000 women; this constellation was predictive of iron stores >4 g in men and >2 g in women. The estimated prevalence per 10,000 of non-C282Y homozygotes with serum ferritin >900 microg/L at evaluation was 7 among Caucasians, 13 among Hispanics, 20 among African Americans, and 38 among Asians and Pacific Islanders, and this constellation was predictive of iron stores >2 g but <4 g. In conclusion, serum ferritin >900 microg/L after initial elevations of both serum ferritin and transferrin saturation is predictive of mildly increased iron stores in multiple ethnic populations regardless of HFE genotype. Serum ferritin >900 microg/L in male C282Y homozygotes is predictive of moderately increased iron stores.


Asunto(s)
Ferritinas/sangre , Sobrecarga de Hierro/diagnóstico , Sobrecarga de Hierro/epidemiología , Hierro/metabolismo , Mediciones Epidemiológicas , Etnicidad , Femenino , Genotipo , Proteína de la Hemocromatosis , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Sobrecarga de Hierro/etnología , Masculino , Proteínas de la Membrana/genética , Mutación Missense , Flebotomía , Valor Predictivo de las Pruebas , Prevalencia
9.
Can J Gastroenterol ; 22(1): 37-40, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18209779

RESUMEN

BACKGROUND AND METHODS: Elevated serum ferritin is a common clinical finding. The etiology of hyperferritinemia in the Asia-Pacific population is less clear due to a low prevalence of known HFE mutations such as C282Y and H63D, as well as an increased prevalence of viral hepatitis and hereditary anemia. A retrospective case review of 80 patients of Asian ethnicity referred to three subspecialists in tertiary care teaching hospitals between January 1997 and March 2005 for assessment of hyperferritinemia was performed. RESULTS: Only four patients (5%) had iron overload on liver biopsy or quantitative phlebotomy. Forty-nine patients (61%) had secondary causes for their hyperferritinemia, of which 26 had liver disease; 16 of those patients also had viral hepatitis. Thirteen patients fulfilled criteria for the insulin resistance syndrome. Other causes included hematological disorders (n=10), malignancy (n=2) and inflammatory arthritis (n=2). Twenty-seven cases (34%) of unexplained hyperferritinemia were found. Of a total of 22 patients who underwent liver biopsy, significant iron deposition was found in one patient. Fifteen patients underwent C282Y and H63D genotyping, with two cases of H63D heterozygosity. Fourteen patients had first-degree relatives with hyperferritinemia. Three families were identified with more than two members affected, which is suggestive of a possible hereditary hyperferritinemia syndrome. CONCLUSION: Secondary causes of elevated ferritin in the Asian population, particularly liver disease, are common, but primary iron overload syndromes appear to be rare. In a significant proportion of patients, the etiology remains unexplained. The genetic basis for hyperferritinemia in Asians is poorly defined and requires further study.


Asunto(s)
Pueblo Asiatico/estadística & datos numéricos , Ferritinas/sangre , Sobrecarga de Hierro/etnología , Sobrecarga de Hierro/etiología , Adulto , Anciano , Anciano de 80 o más Años , Colombia Británica/epidemiología , Femenino , Genotipo , Hospitales de Enseñanza , Humanos , Sobrecarga de Hierro/diagnóstico , Masculino , Persona de Mediana Edad , Fenotipo , Estudios Retrospectivos
11.
Am J Med ; 120(8): 734.e1-9, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17679134

RESUMEN

PURPOSE: We sought to determine the prevalence of elevated measures of iron status in African Americans and whether the combination of serum ferritin concentration >200 microg/L for women or >300 microg/L for men and transferrin saturation in the highest quartile represents increased likelihood of mutation of HFE, self-reported iron overload or self-reported liver disease. SUBJECTS AND METHODS: A cross-sectional observational study of 27,224 African Americans > or =25 years of age recruited in a primary care setting was conducted as part of the multi-center, multi-ethnic Hemochromatosis and Iron Overload Screening (HEIRS) Study. Measurements included serum ferritin concentration, transferrin saturation, testing for HFE C282Y and H63D, and self-reported iron overload and liver disease. RESULTS: Serum ferritin concentration >200 microg/L for women or >300 microg/L for men occurred in 5263 (19.3%) of African Americans, while serum ferritin concentration in this range with highest-quartile transferrin saturation (>29% women; >35% men) occurred in 1837 (6.7%). Adjusted odds of HFE mutation (1.76 women, 1.67 men), self-reported iron overload (1.97 women, 2.88 men), or self-reported liver disease (5.18 women, 3.73 men) were greater with elevated serum ferritin concentration and highest-quartile transferrin saturation than with nonelevated serum ferritin concentration (each P <.05). CONCLUSIONS: Serum ferritin concentration >200 microg/L for women or >300 microg/L for men in combination with transferrin saturation >29% for women or >35% for men occurs in approximately 7% of adult African American primary care patients. Patients with this combination of iron test results should be evaluated for increased body iron stores or liver disease.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Sobrecarga de Hierro/etnología , Hepatopatías/etnología , Adulto , Estudios Transversales , Femenino , Ferritinas/sangre , Genotipo , Proteína de la Hemocromatosis , Hemosiderosis/etnología , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Masculino , Proteínas de la Membrana/genética , Prevalencia , Transferrina/análisis
12.
World J Gastroenterol ; 13(21): 2956-9, 2007 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-17589946

RESUMEN

AIM: To identify the frequency of iron overload and study the three mutations in the HFE gene (C282Y, H63D, and S65C) in patients with chronic liver disorders (CLD) and controls. METHODS: To identify patients with iron overload (transferrin saturation > 45% in females and > 50% in males and serum ferritin > 1000 ng/mL) we evaluated 236 patients with CLD, including 59 with non-alcoholic steatohepatitis (NASH), 22 with alcoholic liver disease (ALD), 19 of cirrhosis due to viruses (HBV, HCV), and 136 with cryptogenic cirrhosis. Mutations of the HFE gene were analyzed by PCR-RE. hundred controls were screened for iron status and the mutations. RESULTS: Seventeen patients with CLD showed evidence of iron overload. Fifteen cases of iron overload had cryptogenic cirrhosis and two had ALD. None of the controls showed iron overload. We did not find any individual with 282Y or 65C either in the cases or in the controls. The prevalence of H63D heterozygosity was 12% in normal individuals, 14.8% in 236 patients (16.9% in NASH, 13.6% in ALD, 26.3% in viral and 12.5% in cryptogenic cirrhosis) and the overall prevalence was 13.98%. Only two of the 17 patients with primary iron overload were heterozygous for H63D. One patient with NASH and one normal individual who were homozygous for H63D showed no iron overload. CONCLUSION: Primary iron overload in Indians is non-HFE type, which is different from that in Europeans and further molecular studies are required to determine the defect in various iron regulatory genes.


Asunto(s)
Hígado Graso/complicaciones , Antígenos de Histocompatibilidad Clase I/genética , Sobrecarga de Hierro/epidemiología , Sobrecarga de Hierro/genética , Cirrosis Hepática/complicaciones , Hepatopatías Alcohólicas/complicaciones , Proteínas de la Membrana/genética , Anciano , Estudios de Casos y Controles , Enfermedad Crónica , Análisis Mutacional de ADN , Hígado Graso/etnología , Hígado Graso/genética , Femenino , Proteína de la Hemocromatosis , Heterocigoto , Antígenos de Histocompatibilidad Clase I/fisiología , Homocigoto , Humanos , India/epidemiología , Sobrecarga de Hierro/complicaciones , Sobrecarga de Hierro/etnología , Cirrosis Hepática/etnología , Cirrosis Hepática/genética , Hepatopatías Alcohólicas/etnología , Hepatopatías Alcohólicas/genética , Masculino , Proteínas de la Membrana/fisiología , Persona de Mediana Edad , Polimorfismo Genético , Prevalencia , Estudios Prospectivos , Población Blanca/etnología , Población Blanca/genética
13.
Blood Cells Mol Dis ; 39(2): 206-11, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17490902

RESUMEN

The ferroportin polymorphism SLC40A1 Q248H (exon 6, cDNA 744G-->T; Gln248His) occurs in persons of sub-Saharan African descent with and without iron overload, and is associated with elevated serum ferritin concentrations (SF). However, the risk of iron overload associated with Q248H has not been defined. We tabulated previously reported Q248H allele frequency estimates in African-Americans and Native Africans, and computed the risk of iron overload associated with Q248H in subjects who lacked HFE C282Y. The aggregate Q248H allele frequency in 1038 African-Americans in two cohorts from Alabama and one cohort each from Washington, DC and California was 0.0525 (95% CI: 0.0451, 0.0652); there was no significant difference in frequencies across these cohorts. The aggregate frequency in 259 Natives from southeast Africa in two cohorts was 0.0946 (95% CI: 0.0694, 0.1198); the difference between the frequencies of these cohorts was not significant. The aggregate Q248H frequencies in African-Americans and Native Africans differed significantly (0.0525 vs. 0.0946, respectively; p=0.0021). There were reports of 24 unrelated African-Americans and 15 unrelated Native Africans without HFE C282Y who had iron overload. In African-Americans, the odds ratio (OR) of Q248H-associated risk of iron overload using 610 C282Y-negative control subjects unselected for SF was 1.57 (95% CI: 0.52, 4.72; p=0.29). In Native Africans, the OR using 208 control subjects unselected for SF was 1.05 (95% CI: 0.28, 3.90; p=0.58). We conclude that the frequency of SLC40A1 Q248H is significantly lower in African-Americans than in Native Africans. Although OR estimates of iron overload in African-Americans and Native Africans with Q248H were greater than unity, the increased OR were not statistically significant.


Asunto(s)
Negro o Afroamericano/genética , Proteínas de Transporte de Catión/genética , Frecuencia de los Genes , Sobrecarga de Hierro/etnología , Sobrecarga de Hierro/genética , África del Sur del Sahara/epidemiología , Negro o Afroamericano/etnología , Predisposición Genética a la Enfermedad/etnología , Predisposición Genética a la Enfermedad/genética , Humanos , Epidemiología Molecular
14.
Intern Med ; 45(20): 1107-11, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17106152

RESUMEN

The different prevalences of iron overload syndromes between Caucasians and Asians may be accounted for by the differences in genetic background. The major mutation of hemochromatosis in Celtic ancestry, C282Y of HFE, was reported in a Japanese patient. Five patients of 3 families with the hepatic transferrin receptor gene (TFR2)-linked hemochromatosis were found in different areas of Japan, suggesting that TFR2 is a major gene in Japanese people. Three patients with mutations in the hemojuvelin gene, HJV, showed also middle-age-onset hemochromatosis. A heterozygous mutation in the H ferritin gene, FTH1, was found in a family of 3 affected patients. Another autosomal dominant SLC40A1-linked hyperferritinemia (ferroportin disease) was found in 3 patients of 2 families. Two patients with hemochromatosis were free from any mutations in the genes investigated. In conclusion, the genetic backgrounds of Japanese patients with primary iron overload syndromes were partially clarified, showing some phenotype-genotype correlations.


Asunto(s)
Pueblo Asiatico/genética , Sobrecarga de Hierro/genética , Adulto , Anciano , Sustitución de Aminoácidos , Proteínas de Transporte de Catión/genética , Femenino , Ferritinas/genética , Proteínas Ligadas a GPI , Genotipo , Hemocromatosis/epidemiología , Hemocromatosis/etnología , Hemocromatosis/genética , Proteína de la Hemocromatosis , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Sobrecarga de Hierro/epidemiología , Sobrecarga de Hierro/etnología , Japón/epidemiología , Masculino , Proteínas de la Membrana/genética , Persona de Mediana Edad , Mutación Missense , Oxidorreductasas , Fenotipo , Mutación Puntual , Proteínas Gestacionales/genética , Receptores de Transferrina/genética
15.
Ethn Dis ; 16(4): 815-21, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17061732

RESUMEN

OBJECTIVE: To assess geographic differences in the frequencies of HFE C282Y and H63D genotypes in six racial/ethnic groups recruited in the Hemochromatosis and Iron Overload Screening (HEIRS) Study. DESIGN: HFE C282Y and H63D genotypes of 97,551 participants, ages > or = 25 years, who reported that they belonged to one of six racial/ethnic groups, were analyzed. HFE genotype frequencies were compared among the racial/ethnic groups and among the HEIRS Study field centers within each racial/ethnic group. RESULTS: The distribution of HFE C282Y and H63D genotypes differed among racial/ethnic groups (P<.0001) and among field centers in Hispanics, Asians, Whites, and Blacks (each P<.05). Genotype frequencies were similar among field centers in Native Americans and Pacific Islanders. Frequencies of C282Y and H63D genotypes were greatest in Whites. The lowest frequencies of C282Y genotypes were observed in Asians; Blacks had the lowest H63D genotype frequencies and the highest frequency of the wild-type genotype. Among racial/ethnic groups, Hispanics had the greatest variation in HFE genotypes across geographic regions. CONCLUSION: HFE C282Y and H63D genotype frequencies vary significantly between racial/ethnic groups and within some racial/ethnic groups across geographic regions.


Asunto(s)
Etnicidad/genética , Hemocromatosis/epidemiología , Hemocromatosis/genética , Antígenos de Histocompatibilidad Clase I/genética , Sobrecarga de Hierro/epidemiología , Sobrecarga de Hierro/genética , Proteínas de la Membrana/genética , Mutación , Grupos Raciales/genética , Adulto , Pueblo Asiatico/genética , Pueblo Asiatico/estadística & datos numéricos , Población Negra/genética , Población Negra/estadística & datos numéricos , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Genotipo , Hemocromatosis/etnología , Proteína de la Hemocromatosis , Hispánicos o Latinos/genética , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Indígenas Norteamericanos/genética , Indígenas Norteamericanos/estadística & datos numéricos , Sobrecarga de Hierro/etnología , Masculino , Nativos de Hawái y Otras Islas del Pacífico/genética , Nativos de Hawái y Otras Islas del Pacífico/estadística & datos numéricos , América del Norte/epidemiología , Población Blanca/genética , Población Blanca/estadística & datos numéricos
19.
N Engl J Med ; 352(17): 1769-78, 2005 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-15858186

RESUMEN

BACKGROUND: Iron overload and hemochromatosis are common, treatable conditions. HFE genotypes, levels of serum ferritin, transferrin saturation values, and self-reported medical history were studied in a multiethnic primary care population. METHODS: Participants were recruited from primary care practices and blood-drawing laboratories. Blood samples were tested for transferrin saturation, serum ferritin, and C282Y and H63D mutations of the HFE gene. Before genetic screening, participants were asked whether they had a history of medical conditions related to iron overload. RESULTS: Of the 99,711 participants, 299 were homozygous for the C282Y mutation. The estimated prevalence of C282Y homozygotes was higher in non-Hispanic whites (0.44 percent) than in Native Americans (0.11 percent), Hispanics (0.027 percent), blacks (0.014 percent), Pacific Islanders (0.012 percent), or Asians (0.000039 percent). Among participants who were homozygous for the C282Y mutation but in whom iron overload had not been diagnosed (227 participants), serum ferritin levels were greater than 300 mug per liter in 78 of 89 men (88 percent) and greater than 200 microg per liter in 79 of 138 women (57 percent). Pacific Islanders and Asians had the highest geometric mean levels of serum ferritin and mean transferrin saturation despite having the lowest prevalence of C282Y homozygotes. There were 364 participants in whom iron overload had not been diagnosed (29 C282Y homozygotes) who had a serum ferritin level greater than 1000 microg per liter. Among men, C282Y homozygotes and compound heterozygotes were more likely to report a history of liver disease than were participants without HFE mutations. CONCLUSIONS: The C282Y mutation is most common in whites, and most C282Y homozygotes have elevations in serum ferritin levels and transferrin saturation. The C282Y mutation does not account for high mean serum ferritin levels and transferrin saturation values in nonwhites.


Asunto(s)
Ferritinas/sangre , Hemocromatosis/genética , Antígenos de Histocompatibilidad Clase I/genética , Proteínas de la Membrana/genética , Mutación , Transferrina/análisis , Artritis/etiología , Complicaciones de la Diabetes , Femenino , Frecuencia de los Genes , Genotipo , Cardiopatías/etiología , Hemocromatosis/complicaciones , Hemocromatosis/etnología , Proteína de la Hemocromatosis , Homocigoto , Humanos , Hierro , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/epidemiología , Sobrecarga de Hierro/etnología , Sobrecarga de Hierro/genética , Hepatopatías/etiología , Modelos Logísticos , Masculino , Fenotipo , Distribución por Sexo , Estados Unidos/epidemiología
20.
Am J Gastroenterol ; 98(7): 1594-8, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12873584

RESUMEN

OBJECTIVE: Genetic susceptibility to iron loading is an important factor in the development of iron overload in Africans. This suggests that persons of African descent may be at risk to develop iron overload with its attendant complications, but relatively little is known about hepatic iron overload among blacks. The aim of this study was to compare the prevalence, histological features, and clinical correlates of hepatic iron overload in a group of autopsied black and white veterans. METHODS: Hepatic iron concentrations (HIC) were determined on liver tissue from autopsies performed at the John Cochran Veterans Affairs Medical Center during the period 1993 to 1996. Clinical information was obtained from autopsy protocols. Sections from livers in which the HIC exceeded the upper limit of normal were examined histologically. RESULTS: Of 256 specimens, 99 were from blacks (39%), whereas 157 were from whites (61%). Thirty-one blacks (31%) had an elevated HIC versus 44 whites (28%) (ns). In the majority of these cases (18 blacks, 30 whites), the HIC was less than twice the upper limit of normal. Nine of 15 subjects with an HIC greater than twice the upper limit of normal and no evident cause of secondary iron overload were black. CONCLUSIONS: The prevalence of mild-to-moderate hepatic iron overload was similar in this group of black and white veterans. Because of the inherent limitations of autopsy studies, prospective assessment of iron stores in healthy blacks is needed to determine more accurately the prevalence and clinical significance of iron overload in this population.


Asunto(s)
Negro o Afroamericano/estadística & datos numéricos , Sobrecarga de Hierro/etnología , Hepatopatías/etnología , Población Blanca/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Cadáver , Humanos , Hierro/metabolismo , Sobrecarga de Hierro/metabolismo , Hígado/metabolismo , Hepatopatías/metabolismo , Persona de Mediana Edad , Missouri/epidemiología , Prevalencia
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...