RESUMEN
BACKGROUND: Increased serum ferritin (SF) in combination with increased total iron binding capacity saturation (TS) in the upper reference internal was evaluated to identify African Americans with increased iron stores. METHODS: Among 16,856 primary care-based African Americans screened at Howard University Field Center of the Hereditary Hemochromatosis and Iron Overload Screening (HEIRS) Study, 142 with SF >500 microg/l women or >700 microg/l men and increased TS (>45% women or >50% men; main study) and 146 with similar ferritin increases and upper reference interval TS (30-45% women or 35-50% men; ancillary study) were offered clinical evaluation to confirm increased SF and identify the cause. RESULTS: Repeat SF remained increased in 83% of 92 participants with increased TS initially (main study) vs 58% of 64 with upper reference interval TS initially (ancillary study) (P=0.0002). These persistent SF increases were associated with blood transfusions (treatment for sickle cell disease) in 20% of 76 main study and 11% of 37 ancillary study participants (P=0.4). Ninety percent of participants with persistent non-transfusional increased SF in the main study and 85% in the ancillary study had alanine-aminotransferase, aspartate-aminotransferase, C-reactive protein and/or hemoglobin values outside of the reference interval. Increased iron stores were documented by phlebotomy or liver biopsy in 4 of 7 main study and 2 of 2 ancillary study participants with persistent non-transfusional increase in SF. CONCLUSION: Increased iron stores occur in African Americans with increased SF in combination with either increased or upper reference interval TS. Limiting clinical evaluation to only those individuals with both increased SF and increased TS will miss individuals with increased iron stores.
Asunto(s)
Negro o Afroamericano/etnología , Ferritinas/sangre , Hierro/sangre , Biopsia , Femenino , Humanos , Hígado/metabolismo , Masculino , Persona de Mediana Edad , FlebotomíaRESUMEN
Iron overload phenotypes in persons with and without hemochromatosis are variable. To investigate this further, probands with hemochromatosis or evidence of elevated iron stores and their family members were recruited for a genome-wide linkage scan to identify potential quantitative trait loci (QTL) that contribute to variation in transferrin saturation (TS), unsaturated iron-binding capacity (UIBC), and serum ferritin (SF). Genotyping utilized 402 microsatellite markers with average spacing of 9 cM. A total of 943 individuals, 64% Caucasian, were evaluated from 174 families. After adjusting for age, gender, and race/ethnicity, there was evidence for linkage of UIBC to chromosome 4q logarithm of the odds (LOD) = 2.08, p = 0.001) and of UIBC (LOD = 9.52), TS (LOD = 4.78), and SF (LOD = 2.75) to the chromosome 6p region containing HFE (each p < 0.0001). After adjustments for HFE genotype and other covariates, there was evidence of linkage of SF to chromosome 16p (LOD = 2.63, p = 0.0007) and of UIBC to chromosome 5q (LOD = 2.12, p = 0.002) and to chromosome 17q (LOD = 2.19, p = 0.002). We conclude that these regions should be considered for fine mapping studies to identify QTL that contribute to variation in SF and UIBC.
Asunto(s)
Pruebas Genéticas/métodos , Genoma Humano , Hemocromatosis/genética , Hierro/metabolismo , Sitios de Carácter Cuantitativo , Adulto , Negro o Afroamericano/genética , Anciano , Pueblo Asiatico/genética , Femenino , Frecuencia de los Genes , Genotipo , Hemocromatosis/etnología , Hemocromatosis/prevención & control , Proteína de la Hemocromatosis , Hispánicos o Latinos/genética , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Indígenas Norteamericanos/genética , Hierro/sangre , Escala de Lod , Masculino , Proteínas de la Membrana/genética , Persona de Mediana Edad , Fenotipo , Población Blanca/genéticaRESUMEN
We compared initial screening transferrin saturation (TfSat) and serum ferritin (SF) phenotypes and HFE C282Y and H63D genotypes of 645 Native American and 43,453 white Hemochromatosis and Iron Overload Screening Study participants who did not report a previous diagnosis of hemochromatosis or iron overload. Elevated measurements were defined as TfSat >50% in men and >45% in women and SF >300 ng/ml in men and >200 ng/ml in women. Mean TfSat was 31% in Native American men and 32% in white men (p = 0.0337) and 25% in Native American women and 27% in white women (p < 0.0001). Mean SF was 153 microg/l in Native American and 151 microg/l in white men (p = 0.8256); mean SF was 55 microg/l in Native American women and 63 microg/l in white women (p = 0.0015). The C282Y allele frequency was 0.0340 in Native Americans and 0.0683 in whites (p < 0.0001). The H63D allele frequency was 0.1150 in Native Americans and 0.1532 in whites (p = 0.0001). We conclude that the screening TfSat and SF phenotypes of Native Americans are similar to those of whites. The allele frequencies of HFE C282Y and H63D are significantly lower in Native Americans than in whites.
Asunto(s)
Ferritinas/metabolismo , Hemocromatosis/genética , Antígenos de Histocompatibilidad Clase I/genética , Indígenas Norteamericanos/genética , Sobrecarga de Hierro/genética , Proteínas de la Membrana/genética , Transferrina/metabolismo , Población Blanca/genética , Adulto , Anciano , Femenino , Ferritinas/genética , Frecuencia de los Genes , Genotipo , Hemocromatosis/diagnóstico , Hemocromatosis/metabolismo , Proteína de la Hemocromatosis , Humanos , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/diagnóstico , Masculino , Persona de Mediana Edad , Fenotipo , Transferrina/genéticaRESUMEN
BACKGROUND: Kaposi's sarcoma (KS) associated with human immunodeficiency virus type 1 (HIV-1) is the most common malignancy in patients with AIDS. It has been most commonly reported in white homosexual men, though a few cases have been reported in blacks. METHODS: We conducted a retrospective analysis of all HIV-1 seropositive patients with biopsy-proven KS seen at Howard University Hospital between February 1985 and June 1995. RESULTS: Of the 73 patients identified, 66 (90%), 4 were white, 2 were Hispanic, and 1 was of unidentified race. The median age was 32 years. Forty-eight (66%) were homosexual or bisexual men, and 10 (14%) were homosexual or bisexual with a history of intravenous drug use (IDU). A history of IDU or blood transfusion was the only risk factor in 7 (9%) and 2 (3%), respectively. The other 6 (8)% were heterosexual. The median survival was 2.2 years. A CD4 count <200 and the presence of an opportunistic infection were associated with shortened survival. CONCLUSIONS: The predominant risk factor for HIV-1-associated KS was homosexual or bisexual activity. Only a few women with KS were identified, and they also reported sexual transmission from male bisexuals and/or drug users. Poor survival was associated with CD4 <200, stage III and IV KS at presentation, and opportunistic infections.
Asunto(s)
Población Negra , Infecciones por VIH/epidemiología , VIH-1 , Sarcoma de Kaposi/epidemiología , Neoplasias Cutáneas/epidemiología , Población Urbana/estadística & datos numéricos , Adulto , Bisexualidad/estadística & datos numéricos , District of Columbia/epidemiología , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/transmisión , VIH-1/inmunología , Homosexualidad Masculina/estadística & datos numéricos , Hospitales Urbanos/estadística & datos numéricos , Humanos , Masculino , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Sarcoma de Kaposi/inmunología , Neoplasias Cutáneas/inmunología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Abuso de Sustancias por Vía Intravenosa/epidemiología , Abuso de Sustancias por Vía Intravenosa/inmunología , Tasa de SupervivenciaRESUMEN
The incidence of cancer in patients with sickle cell disease (SCD) is not known. The 10-year follow-up data on 696 patients with SCD was analyzed at our institution in order to determine the cancer incidence and cancer mortality rates. The age range was 18 to 79 years, with a mean age of 28.8 years. There were 377 females and 319 males. The median follow-up was 3 years. Five patients developed cancer during this period. The cancer incidence rate was 5/2,864 or 1.74 per 1,000 patient years. The 95% CI was 0.64 to 4.32 per 1,000 patient years. There were 68 deaths with 3 being due to cancer. The cancer mortality rate was 3/2,873 or 1.04 cases per 1,000 patient years. Our data represent the first published paper that the authors are aware of, where the cancer incidence and mortality rates have been calculated for any group of patients with SCD.
Asunto(s)
Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/mortalidad , Neoplasias/etiología , Adolescente , Adulto , Anciano , District of Columbia/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias/epidemiologíaRESUMEN
This study evaluates the impact of health insurance as a substitute for social class on tumor location, presentation, stage, grade, and age-adjusted survival in an African-American population. Patients were stratified by insurance into two groups: group 1 (private insurance and Medicare parts A & B) and group 2 (Medicaid, Medical Charity, self-pay, uninsured, or unemployed). A total of 212 patients were evaluated. Of these, 210 patients were insured or had Medical Charity, and two were uninsured. The type of health insurance did not significantly affect age-adjusted survival. However, age and stage at presentation were positive predictors of age-adjusted survival. Higher socioeconomic status was associated with group 1 health insurance.