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1.
Ann Hematol ; 103(6): 2173-2176, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38637332

RESUMO

A 58-year-old female was found to have hyperferritinemia (Serum ferritin:1683 ng/mL) during work-up for mild normocytic anemia. Transferrin saturation(TSAT) was low-normal. Magnetic resonance imaging (MRI) abdomen showed evidence of hepatic iron deposition. Liver biopsy showed 4 + hepatic iron deposition without any evidence of steatosis or fibrosis. Quantitative liver iron was elevated at 348.3 µmol/g dry liver weight [Reference range(RR): 3-33 µmol/g dry liver weight]. She was presumptively diagnosed with tissue iron overload, cause uncertain. A diagnosis of ferroportin disease (FD) was considered, but the pattern of iron distribution in the liver, mainly within the hepatic parenchyma (rather than in the hepatic Kupffer cells seen in FD), and the presence of anemia (uncommon in FD) made this less likely. She was treated with intermittent phlebotomy for over a decade with poor tolerance due to worsening normocytic to microcytic anemia. A trial of deferasirox was done but it was discontinued after a month due to significant side effects. During the course of treatment, her ferritin level decreased. Over the past 1.5 years, she developed progressively worsening neurocognitive decline. MRI brain showed areas of susceptibility involving basal ganglia, midbrain and cerebellum raising suspicion for metabolic deposition disease. Neuroimaging findings led to testing for serum copper and ceruloplasmin levels which were both found to be severely low. Low serum copper, ceruloplasmin levels and neuroimaging findings led us to consider Wilson disease however prior liver biopsy showing elevated hepatic iron rather than hepatic copper excluded the diagnosis of Wilson disease. After shared decision making, ceruloplasmin gene analysis was not pursued due to patient's preference and prohibitive cost of testing. The diagnosis of aceruloplasminemia was ultimately made. The biochemical triad of hyperferritinemia, low-normal TSAT and microcytic anemia should raise the possibility of aceruloplasminemia. Since neurological manifestations are rare in most inherited iron overload syndromes, neurological symptoms in a patient with tissue iron overload should prompt consideration of aceruloplasminemia as a differential diagnosis.


Assuntos
Ceruloplasmina , Distúrbios do Metabolismo do Ferro , Imageamento por Ressonância Magnética , Humanos , Feminino , Pessoa de Meia-Idade , Ceruloplasmina/deficiência , Ceruloplasmina/análise , Distúrbios do Metabolismo do Ferro/diagnóstico , Distúrbios do Metabolismo do Ferro/genética , Doenças Neurodegenerativas/diagnóstico , Fígado/patologia , Fígado/metabolismo , Fígado/diagnóstico por imagem , Ferritinas/sangue , Ferro/metabolismo , Ferro/sangue , Diagnóstico Diferencial , Sobrecarga de Ferro/diagnóstico , Deferasirox/uso terapêutico
2.
Ann Hepatol ; 17(5): 871-879, 2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30145563

RESUMO

INTRODUCTION AND AIM: We sought to identify independent risk factors for cirrhosis in HFE p.C282Y homozygotes in a cross-sectional study. MATERIAL AND METHODS: We evaluated 368 p.C282Y homozygotes who underwent liver biopsy and compared characteristics of those with and without cirrhosis. We performed multivariable logistic regression on cirrhosis with: age; sex; race/ethnicity; diabetes; blood pints/units donated voluntarily; erythrocyte pints/units received; iron supplement use; alcohol intake, g/d; body mass index, kg/m2; swollen/tender 2nd/3rd metacarpophalangeal joints; elevated alanine aminotransferase; elevated aspartate aminotransferase; steatosis/fatty liver; iron removed by phlebotomy, g; and GNPAT p.D519G positivity. RESULTS: Mean age of 368 participants (73.6% men) was 47 ± 13 (standard deviation) y. Cirrhosis was diagnosed in 86 participants (23.4%). Participants with cirrhosis had significantly greater mean age, proportion of men, diabetes prevalence, mean daily alcohol intake, prevalence of swollen/ tender 2nd/3rd metacarpophalangeal joints, mean serum ferritin, elevated alanine aminotransferase, elevated aspartate aminotransferase, and mean iron removed; and significantly fewer mean blood pints/units donated. GNPAT p.D519G positivity was detected in 82 of 188 participants (43.6%). In a multivariable model for cirrhosis, there were four significant positive associations: age (10-y intervals) (odds ratio 2.2 [95% confidence interval 1.5, 3.3]); diabetes (3.3; [1.1, 9.7]); alcohol intake (14 g alcohol drinks/d) (1.5 [1.2, 1.8]); and iron removed, g (1.3 [1.2, 1.4]). There was no statistical evidence of two-way interactions between these variables. CONCLUSION: In conclusion, cirrhosis in HFE p.C282Y homozygotes is significantly associated with age, diabetes, daily alcohol intake, and iron removed by phlebotomy, taking into account the effect of other variables.


Assuntos
Proteína da Hemocromatose/genética , Hemocromatose/genética , Homozigoto , Cirrose Hepática/genética , Mutação , Aciltransferases/genética , Adulto , Fatores Etários , Consumo de Bebidas Alcoólicas/efeitos adversos , Consumo de Bebidas Alcoólicas/epidemiologia , Austrália/epidemiologia , Comorbidade , Estudos Transversais , Diabetes Mellitus/epidemiologia , Feminino , Predisposição Genética para Doença , Hemocromatose/diagnóstico , Hemocromatose/epidemiologia , Hemocromatose/terapia , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Flebotomia , Polimorfismo de Nucleotídeo Único , Prevalência , Medição de Risco , Fatores de Risco , Estados Unidos/epidemiologia
3.
Blood Cells Mol Dis ; 63: 15-20, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27936396

RESUMO

BACKGROUND: GNPAT p.D519G positivity is significantly increased in HFE p.C282Y homozygotes with markedly increased iron stores. We sought to determine associations of p.D519G and iron-related variables with iron stores in p.C282Y homozygotes. METHODS: We defined markedly increased iron stores as serum ferritin >2247pmol/L (>1000µg/L) and either hepatic iron >236µmol/g dry weight or iron >10g by induction phlebotomy (men and women). We defined normal or mildly elevated iron stores as serum ferritin <674.1pmol/L (<300µg/L) or either age≥40y with iron ≤2.5g iron by induction phlebotomy or age≥50y with ≤3.0g iron by induction phlebotomy (men only). We compared participant subgroups using univariate methods. Using multivariable logistic regression, we evaluated associations of markedly increased iron stores with these variables: age; iron supplement use (dichotomous); whole blood units donated; erythrocyte units received as transfusion; daily alcohol consumption, g; and p.D519G positivity (heterozygosity or homozygosity). RESULTS: The mean age of 56 participants (94.6% men) was 55±10 (SD) y; 41 had markedly increased iron stores. Prevalences of swollen/tender 2nd/3rd metacarpophalangeal joints and elevated aspartate or alanine aminotransferase were significantly greater in participants with markedly increased iron stores. Only participants with markedly increased iron stores had cirrhosis. In multivariable analyses, p.D519G positivity was the only exposure variable significantly associated with markedly increased iron stores (odds ratio 9.9, 95% CI [1.6, 60.3], p=0.0126). CONCLUSIONS: GNPAT p.D519G is strongly associated with markedly increased iron stores in p.C282Y homozygotes after correction for age, iron-related variables, and alcohol consumption.


Assuntos
Aciltransferases/genética , Proteína da Hemocromatose/genética , Ferro/metabolismo , Mutação de Sentido Incorreto , Aciltransferases/metabolismo , Adulto , Fatores Etários , Idoso , Consumo de Bebidas Alcoólicas , Feminino , Proteína da Hemocromatose/metabolismo , Homozigoto , Humanos , Masculino , Pessoa de Meia-Idade
4.
Hepatology ; 62(2): 429-39, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25605615

RESUMO

UNLABELLED: To identify polymorphisms associated with variability of iron overload severity in HFE-associated hemochromatosis, we performed exome sequencing of DNA from 35 male HFE C282Y homozygotes with either markedly increased iron stores (n = 22; cases) or with normal or mildly increased iron stores (n = 13; controls). The 35 participants, residents of the United States, Canada, and Australia, reported no or light alcohol consumption. Sequencing data included 82,068 single-nucleotide variants, and 10,337 genes were tested for a difference between cases and controls. A variant in the GNPAT gene showed the most significant association with severe iron overload (P = 3 × 10(-6) ; P = 0.033 by the likelihood ratio test after correction for multiple comparisons). Sixteen of twenty-two participants with severe iron overload had glyceronephosphate O-acyltransferase (GNPAT) polymorphism p.D519G (rs11558492; 15 heterozygotes, one homozygote). No control participant had this polymorphism. To examine functional consequences of GNPAT deficiency, we performed small interfering RNA-based knockdown of GNPAT in the human liver-derived cell line, HepG2/C3A. This knockdown resulted in a >17-fold decrease in expression of the messenger RNA encoding the iron-regulatory hormone, hepcidin. CONCLUSION: GNPAT p.D519G is associated with a high-iron phenotype in HFE C282Y homozygotes and may participate in hepcidin regulation.


Assuntos
Aciltransferases/genética , Variação Genética , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Sobrecarga de Ferro/genética , Proteínas de Membrana/genética , Alelos , Análise de Variância , Western Blotting , Estudos de Casos e Controles , Exoma/genética , Exoma/fisiologia , Ferritinas/sangue , Hemocromatose/fisiopatologia , Proteína da Hemocromatose , Células Hep G2 , Homozigoto , Humanos , Sobrecarga de Ferro/fisiopatologia , Cirrose Hepática/genética , Cirrose Hepática/fisiopatologia , Masculino , Fenótipo , Mutação Puntual , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Análise de Sequência de Proteína , Índice de Gravidade de Doença
9.
J Clin Gastroenterol ; 43(6): 569-73, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19359997

RESUMO

OBJECTIVE: There are limited data comparing hepatic phenotype among hemochromatosis patients with different HFE genotypes. The goal of this study was to compare hepatic histopathologic features and hepatic iron concentration (HIC) among patients with phenotypic hemochromatosis and different HFE genotypes. METHODS: We studied 182 US patients with phenotypic hemochromatosis. Degree of hepatic fibrosis, pattern of iron deposition, presence of steatosis or necroinflammation, and HIC were compared among different HFE genotypes. RESULTS: C282Y/H63D compound heterozygotes and patients with HFE genotypes other than C282Y/C282Y were more likely to have stainable Kupffer cell iron (31.1% vs. 9.5%; P=0.02), portal or lobular inflammation (28.9% vs. 15.6%; P=0.03), and steatosis (33.3% vs. 10.2%; P<0.01) on liver biopsy than C282Y homozygotes. Mean log10 HIC (P<0.05) and log10 ferritin (P<0.05) were higher among C282Y homozygotes than in patients with other HFE genotypes. In a logistic regression analysis using age, sex, HFE genotype, log10 ferritin, and log10 HIC as independent variables, log10 serum ferritin (P=0.0008), male sex (P=0.0086), and log10 HIC (P=0.047), but not HFE genotype (P=0.0554) were independently associated with presence or absence of advanced hepatic fibrosis. CONCLUSIONS: C282Y/H63D compound heterozygotes and other non-C282Y homozygotes which express the hepatic hemochromatosis phenotype frequently have evidence of steatosis or chronic hepatitis and lower body iron stores than C282Y homozygotes. These data suggest that presence of concomitant liver disease may explain expression of the hemochromatosis phenotype among non-C282Y homozygotes. Increased age, HIC, and ferritin are associated with advanced hepatic fibrosis, regardless of HFE genotype.


Assuntos
Hemocromatose/genética , Hemocromatose/patologia , Heterozigoto , Antígenos de Histocompatibilidade Classe I/genética , Homozigoto , Proteínas de Membrana/genética , Adulto , Estudos de Coortes , Feminino , Ferritinas/sangue , Genótipo , Proteína da Hemocromatose , Humanos , Ferro/sangue , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/genética , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Fenótipo
10.
Ann Intern Med ; 149(4): 270-2, 2008 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-18711158

RESUMO

The discovery of the HFE gene in 1996 heralded a decade of major advances in the understanding of the mechanisms that control iron absorption and body iron stores. A genetic definition of the common form of hereditary hemochromatosis became possible, and testing for the common causative HFE mutations is now widely available in clinical laboratories. Several population screening studies have confirmed that disease penetrance in HFE-related hereditary hemochromatosis is lower than previously believed, making universal population-based screening for this disorder unattractive. However, hereditary hemochromatosis may still cause morbidity and mortality because of iron overload. Early detection and use of appropriate therapy can prevent these manifestations and can only be achieved by targeted case finding. In this article, the authors draw attention again to hereditary hemochromatosis as a cause of preventable organ dysfunction and propose targeted case finding for Caucasian men of Northern European ancestry.


Assuntos
Testes Genéticos , Hemocromatose/diagnóstico , Hemocromatose/genética , Antígenos de Histocompatibilidade Classe I/genética , Proteínas de Membrana/genética , Análise Custo-Benefício , Diagnóstico Precoce , Testes Genéticos/economia , Genótipo , Proteína da Hemocromatose , Humanos , Mutação , Fenótipo , Fatores de Risco
11.
Am J Hematol ; 83(4): 263-70, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17924547

RESUMO

Deferoxamine mesylate (DFO) reduces morbidity and mortality associated with transfusional iron overload. Data on the utilization and costs of care among U.S. patients receiving DFO in typical clinical practice are limited however. This was a retrospective study using a large U.S. health insurance claims database spanning 1/97-12/04 and representing 40 million members in >70 health plans. Study subjects (n = 145 total, 106 sickle cell disease [SCD], 39 thalassemia) included members with a diagnosis of thalassemia or SCD, one or more transfusions (whole blood or red blood cells), and one or more claims for DFO. Mean transfusion episodes were 12 per year. Estimated mean DFO use was 307 g/year. Central venous access devices were required by 20% of patients. Cardiac disease was observed in 16% of patients. Mean total medical costs were $59,233 per year including $10,899 for DFO and $8,722 for administration of chelation therapy. In multivariate analyses, potential complications of iron overload were associated with significantly higher medical care costs. In typical clinical practice, use of DFO in patients with thalassemia and SCD receiving transfusions is low. Administration costs represent a large proportion of the cost of chelation therapy. Potential complications of iron overload are associated with increased costs.


Assuntos
Anemia Falciforme/terapia , Terapia por Quelação/estatística & dados numéricos , Desferroxamina/uso terapêutico , Quelantes de Ferro/uso terapêutico , Ferro , Talassemia/terapia , Adolescente , Adulto , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/epidemiologia , Cardiomiopatias/epidemiologia , Cardiomiopatias/etiologia , Terapia por Quelação/economia , Criança , Pré-Escolar , Bases de Dados Factuais/estatística & dados numéricos , Custos de Medicamentos , Feminino , Humanos , Lactente , Ferro/efeitos adversos , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/tratamento farmacológico , Sobrecarga de Ferro/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Talassemia/complicações , Talassemia/epidemiologia , Reação Transfusional , Resultado do Tratamento , Estados Unidos/epidemiologia
12.
Am J Hematol ; 83(8): 618-26, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18429050

RESUMO

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.


Assuntos
Ferritinas/sangue , Sobrecarga de Ferro/diagnóstico , Sobrecarga de Ferro/epidemiologia , Ferro/metabolismo , Medidas em Epidemiologia , Etnicidade , Feminino , Genótipo , Proteína da Hemocromatose , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Sobrecarga de Ferro/etnologia , Masculino , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Flebotomia , Valor Preditivo dos Testes , Prevalência
13.
Pharmacoeconomics ; 25(4): 329-42, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17402805

RESUMO

BACKGROUND: Deferasirox is a recently approved once-daily oral iron chelator that has been shown to reduce liver iron concentrations and serum ferritin levels to a similar extent as infusional deferoxamine. OBJECTIVE: To determine the cost effectiveness of deferasirox versus deferoxamine in patients with beta-thalassaemia major from a US healthcare system perspective. METHODS: A Markov model was used to estimate the total additional lifetime costs and QALYs gained with deferasirox versus deferoxamine in patients with beta-thalassaemia major and chronic iron overload from blood transfusions. Patients were assumed to be 3 years of age at initiation of chelation therapy and to receive prescribed dosages of deferasirox and deferoxamine that have been shown to be similarly effective in such patients. Compliance with chelation therapy and probabilities of iron overload-related cardiac disease and death by degree of compliance were estimated using data from published studies. Costs ($US, year 2006 values) of deferoxamine administration and iron overload-related cardiac disease were based on analyses of health insurance claims of transfusion-dependent thalassaemia patients. Utilities were based on a study of patient preferences for oral versus infusional chelation therapy, as well as published literature. Probabilistic and deterministic sensitivity analyses were employed to examine the robustness of the results to key assumptions. RESULTS: Deferasirox resulted in a gain of 4.5 QALYs per patient at an additional expected lifetime cost of $US126,018 per patient; the cost per QALY gained was $US28,255. The cost effectiveness of deferasirox versus deferoxamine was sensitive to the estimated costs of deferoxamine administration and the quality-of-life benefit associated with oral versus infusional therapy. Cost effectiveness was also relatively sensitive to the equivalent daily dose of deferasirox, and the unit costs of deferasirox and deferoxamine, and was more favourable in younger patients. CONCLUSION: Results of this analysis of the cost effectiveness of oral deferasirox versus infusional deferoxamine suggest that deferasirox is a cost effective iron chelator from a US healthcare perspective.


Assuntos
Benzoatos/economia , Benzoatos/uso terapêutico , Transfusão de Sangue/métodos , Triazóis/economia , Triazóis/uso terapêutico , Administração Oral , Benzoatos/administração & dosagem , Transfusão de Sangue/economia , Análise Custo-Benefício , Deferasirox , Atenção à Saúde/economia , Atenção à Saúde/métodos , Esquema de Medicação , Revisão de Uso de Medicamentos/estatística & dados numéricos , Farmacoeconomia/estatística & dados numéricos , Farmacoeconomia/tendências , Humanos , Infusões Intravenosas , Revisão da Utilização de Seguros/estatística & dados numéricos , Quelantes de Ferro/administração & dosagem , Quelantes de Ferro/economia , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Cadeias de Markov , Resultado do Tratamento , Triazóis/administração & dosagem , Estados Unidos , Talassemia beta/tratamento farmacológico
16.
Ann Intern Med ; 138(8): 627-33, 2003 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12693884

RESUMO

BACKGROUND: DNA-based HFE gene testing can confirm hereditary hemochromatosis in most people of Northern European descent. However, liver biopsy is important to detect cirrhosis. OBJECTIVE: To develop noninvasive criteria to predict the presence or absence of advanced hepatic fibrosis or cirrhosis in Americans with hemochromatosis. DESIGN: Cross-sectional study. SETTING: Six tertiary care referral clinics. PATIENTS: 182 patients with phenotypically defined hemochromatosis. MEASUREMENTS: Liver histopathology and serum ferritin, aspartate aminotransferase, and alanine aminotransferase levels. Multivariate logistic regression analysis was used to examine factors associated with cirrhosis (defined as bridging fibrosis or unequivocal cirrhosis on biopsy). RESULTS: Cirrhosis was present in 40 of 182 (22%) patients in the overall group and in 35 of 147 (24%) of C282Y homozygotes. Only 1 of 93 patients with a serum ferritin level less than 1000 microg/L had cirrhosis compared with 39 of 89 patients with serum ferritin levels greater than 1000 microg/L (P < 0.001). No C282Y homozygotes or C282Y/H63D compound heterozygotes with serum ferritin levels less than 1000 microg/L had cirrhosis. Elevated serum aminotransferase levels (P = 0.001) and serum ferritin levels greater than 1000 microg/L (P = 0.001), but not age older than 40 years (P = 0.2), were independently associated with cirrhosis. In a multivariate model, the probability of cirrhosis was 7.4% among patients with serum ferritin levels less than 1000 microg/L compared with 72% among patients with serum ferritin levels greater than 1000 microg/L after adjustment for age and elevated serum liver enzyme levels. CONCLUSIONS: Patients with hemochromatosis and serum ferritin levels less than 1000 microg/L are unlikely to have cirrhosis. Liver biopsy to screen for cirrhosis may be unnecessary in such patients, regardless of age or serum liver enzyme levels.


Assuntos
Ferritinas/sangue , Hemocromatose/complicações , Cirrose Hepática/diagnóstico , Adulto , Fatores Etários , Alanina Transaminase/sangue , Aspartato Aminotransferases/sangue , Biópsia , Estudos Transversais , Homozigoto , Humanos , Fígado/enzimologia , Fígado/patologia , Cirrose Hepática/etiologia , Testes de Função Hepática , Modelos Logísticos , Pessoa de Meia-Idade , Mutação , Fenótipo , Curva ROC , Análise de Regressão , Estados Unidos
17.
Curr Med Res Opin ; 25(1): 139-47, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19210147

RESUMO

BACKGROUND: Patients with myelodysplastic syndrome (MDS) and other acquired hematopoietic disorders frequently require chronic transfusion therapy. Although red cell transfusions are known to cause iron overload, data on the risk of iron-related complications in these patients are limited. METHODS: This was a retrospective, case-control study to assess the association between exposure to transfusions and complications of iron overload in patients with MDS and other hematopoietic disorders using a large US health-insurance claims database spanning 1997-2004. Subjects included members with one or more claims with a diagnosis of 'neoplasm of uncertain behavior of other lymphatic and hematopoietic tissues' (ICD-9-CM 238.7) and no claims for potential complications of iron overload (cardiomyopathy/heart failure, conduction/rhythm disorders, diabetes, liver disease) prior to the diagnosis date. Cases were defined as subjects with claims for complications of iron overload after the diagnosis date and were compared with a corresponding number of controls (patients without complications) with respect to receipt of transfusions, controlling for demographic and clinical characteristics using multivariate conditional logistic regression. RESULTS: A total of 4546 patients met inclusion criteria including 511 cases and a corresponding number of controls. Receipt of transfusions was significantly associated with risk of potential complications of iron overload (odds ratio [OR] = 2.90; p = 0.0008). Results for specific potential complications were as follows: cardiomyopathy/heart failure (OR = 1.62; p = 0.2955), conduction/rhythm disorders (OR = 4.18; p = 0.0005), diabetes (OR = 5.06; p = 0.0025), and liver disease (OR = 3.31; p = 0.0008). CONCLUSION: These results suggest that transfusion therapy may increase risk of complications of iron overload in patients with MDS or other hematopoietic disorders. Further research is needed to assess whether the associations observed in this retrospective observational study are due to iron overload or other factors.


Assuntos
Doenças da Medula Óssea/terapia , Sobrecarga de Ferro/etiologia , Síndromes Mielodisplásicas/terapia , Reação Transfusional , Doenças da Medula Óssea/metabolismo , Estudos de Casos e Controles , Humanos , Classificação Internacional de Doenças , Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/tratamento farmacológico , Síndromes Mielodisplásicas/metabolismo , Estudos Retrospectivos
18.
Transfusion ; 47(10): 1919-29, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17880620

RESUMO

BACKGROUND: Patients with thalassemia major require iron chelation therapy (ICT) to prevent complications from transfusional iron overload. Deferoxamine is effective, but requires administration as a slow continuous subcutaneous or intravenous infusion five to seven times per week. Deferiprone is a three-times-daily oral iron chelator, but has limited availability in the United States. Deferasirox is a once-daily oral iron chelator that was approved in the United States in 2005 for patients older than 2 years of age with transfusional iron overload. STUDY DESIGN AND METHODS: Published evidence on rates of compliance with ICT and the association between compliance, and the incidence and costs of complications of iron overload, in patients with thalassemia major was reviewed. RESULTS: A total of 18 studies were identified reporting data on compliance with ICT, including 7 that examined deferoxamine only, 6 that examined deferiprone only, and 5 that compared deferoxamine and deferiprone; no studies reporting compliance with deferasirox were identified. In studies of deferoxamine only, estimated mean compliance ranged from 59 to 78 percent. Studies of deferiprone generally reported better compliance, ranging from 79 to 98 percent. Results of comparative studies of deferoxamine and deferiprone suggest that compliance may be better with oral therapy. Numerous studies demonstrate that that poor compliance with ICT results in increased risk of cardiac disease and endocrinopathies, as well as lower survival. Although data on the costs of noncompliance are limited, a recent model-based study estimated the lifetime costs of inadequate compliance with deferoxamine to be $33,142. CONCLUSIONS: Inadequate compliance with ICT in thalassemia major is common and results in substantial morbidity and mortality, as well as increased costs.


Assuntos
Quelantes de Ferro/uso terapêutico , Sobrecarga de Ferro/prevenção & controle , Talassemia/terapia , Reação Transfusional , Recusa do Paciente ao Tratamento/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Efeitos Psicossociais da Doença , Deferiprona , Desferroxamina/uso terapêutico , Humanos , Quelantes de Ferro/economia , Pessoa de Meia-Idade , Cooperação do Paciente , Piridonas/uso terapêutico , Talassemia/tratamento farmacológico , Talassemia/economia , Talassemia/psicologia
19.
Blood Cells Mol Dis ; 34(2): 157-61, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15727899

RESUMO

Hereditary hemochromatosis is a common disorder of iron metabolism most frequently associated with mutations in the HFE gene. Hereditary hemochromatosis may be caused by other less common genetic mutations including those in the ferroportin gene. Whereas hereditary hemochromatosis associated with HFE mutations is an autosomal recessive disorder, essentially all cases of hereditary hemochromatosis associated with ferroportin mutations follow an autosomal dominant pattern of inheritance, and most cases are notable for the lack of an elevated transferrin saturation and presence of iron deposition in Kupffer cells. This report describes the clinical and laboratory features of a family with hereditary hemochromatosis associated with a previously unrecognized ferroportin mutation (Cys326Ser). Three generations of the family are described. The disease in this family is notable for young age at onset, elevated transferrin saturation values, and hepatocyte iron deposition. The distinct molecular and clinical features reflect the heterogeneous nature of this disease.


Assuntos
Proteínas de Transporte de Cátions/genética , Hemocromatose/genética , Mutação de Sentido Incorreto , Adolescente , Adulto , Substituição de Aminoácidos , Criança , Feminino , Genes Dominantes , Humanos , Masculino , Linhagem
20.
Hematology ; 8(6): 429-32, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14668040

RESUMO

We sought to establish the relationship of quantitative hepatic iron measurements and phlebotomy-mobilized iron in a large sample of HFE C282Y homozygotes with a hemochromatosis phenotype. Thus, we analyzed data from 79 unrelated C282Y homozygotes from treatment centers in Rochester, NY and Birmingham, AL who had undergone liver biopsy with measurement of hepatic iron content and who had achieved iron depletion (serum ferritin <25 ng/l) with quantitative phlebotomy. The sample consisted of 57 men and 22 women; their median age at diagnosis was 47 years (range 23-76 years). Sixty-three of 79 (79.7%) had hepatic iron index (HII; µmol/g dry weight of liver divided by age in years) ≥1.9, a conventional phenotypic definition of hemochromatosis. The mean quantity of phlebotomy-mobilized iron (± 1 sd) was 6.4 g (±4.0 g) in men (range 2.0-18.0 g) and 6.2 g (±5.8) in women (range 0.7-22.5 g). There was a significant positive correlation of liver iron levels with phlebotomy-mobilized iron in this patient sample (Pearson coefficient 0.75; R

2
=55.5%). This relationship was also demonstrable when data from males and females were analyzed separately. We calculated a phlebotomy-mobilized iron index (MII: phlebotomy-mobilized iron in mg divided by age in years) using the corresponding regression equations and evaluated its use as a surrogate for HII. Thus, a phlebotomy-mobilized iron of 3.5 g corresponds to liver iron levels of 80 µmol/g dry weight, and a MII of 80 corresponds to HII of 1.9. Forty-six of 79 subjects met all four phenotypic criteria for hemochromatosis (liver iron levels ≥80 µmol/g, HII≥1.9, phlebotomy-mobilized iron ≥3.5 g and MII≥80). Of the 20 subjects with MII<80, 9 had a HII≥1.9. Conversely, 5 of 16 subjects with HII<1.9 had MII≥80 and 8 had phlebotomy-mobilized iron ≥3.5 g. Most patients with a hemochromatosis phenotype and evidence of moderate or severe iron overload (>80%) are homozygous for the common HFE missense mutation C282Y. Thus, clinicians rely increasingly on HFE mutation analysis to diagnose hemochromatosis and on quantitative phlebotomy to estimate the severity of iron overload in many cases. Liver biopsy is now employed in selected patients to visualize fibrosis or cirrhosis and to identify coincidental hepatic disease. We conclude that the use of the MII permits a retrospective estimation of the age-adjusted severity of iron overload that has a diagnostic value similar to that of the HII in hemochromatosis patients with C282Y homozygosity.


Assuntos
Hemocromatose/metabolismo , Ferro/metabolismo , Fígado/metabolismo , Flebotomia/métodos , Adulto , Idoso , Feminino , Hemocromatose/diagnóstico , Hemocromatose/genética , Proteína da Hemocromatose , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Sobrecarga de Ferro/genética , Sobrecarga de Ferro/metabolismo , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Adulto Jovem
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