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ATRX is an X-linked gene of the SWI/SNF family, mutations in which cause syndromal mental retardation and downregulation of α-globin expression. Here we show that ATRX binds to tandem repeat (TR) sequences in both telomeres and euchromatin. Genes associated with these TRs can be dysregulated when ATRX is mutated, and the change in expression is determined by the size of the TR, producing skewed allelic expression. This reveals the characteristics of the affected genes, explains the variable phenotypes seen with identical ATRX mutations, and illustrates a new mechanism underlying variable penetrance. Many of the TRs are G rich and predicted to form non-B DNA structures (including G-quadruplex) in vivo. We show that ATRX binds G-quadruplex structures in vitro, suggesting a mechanism by which ATRX may play a role in various nuclear processes and how this is perturbed when ATRX is mutated.
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ADN Helicasas/metabolismo , Proteínas Nucleares/metabolismo , Animales , Células Cultivadas , Inmunoprecipitación de Cromatina , Cromosomas de los Mamíferos/metabolismo , Islas de CpG , ADN Helicasas/genética , ADN Ribosómico/metabolismo , G-Cuádruplex , Expresión Génica , Estudio de Asociación del Genoma Completo , Histonas/metabolismo , Humanos , Ratones , Repeticiones de Minisatélite , Mutación , Proteínas Nucleares/genética , Telómero/metabolismo , Proteína Nuclear Ligada al Cromosoma XRESUMEN
Alpha-thalassemia is an inherited blood disorder caused by impaired α-globin chain production, leading to anemia and other complications. Hemoglobin H (HbH) disease is caused by a combination of mutations generally affecting the expression of three of four α-globin alleles; disease severity is highly heterogeneous, largely driven by genotype. Notably, non-deletional mutations cause a greater degree of ineffective erythropoiesis and hemolysis, higher transfusion burden, and increased complication risks versus deletional mutations. There are limited treatment options for HbH disease, and effective therapies are needed. This review discusses the pathophysiology of HbH disease, current management strategies, unmet needs, and emerging treatment options.
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In this review, we provide a summary of evidence on iron overload in young children with transfusion-dependent ß-thalassemia (TDT) and explore the ideal timing for intervention. Key data from clinical trials and observational studies of the three available iron chelators deferoxamine, deferiprone, and deferasirox are also evaluated for inclusion of subsets of young children, especially those less than 6 years of age. Evidence on the efficacy and safety of iron chelation therapy for children ≥2 years of age with transfusional iron overload is widely available. New data exploring the risks and benefits of early-start iron chelation in younger patients with minimal iron overload are also emerging.
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Transfusión Sanguínea , Terapia por Quelación , Quelantes del Hierro , Sobrecarga de Hierro , Talasemia beta , Humanos , Talasemia beta/terapia , Talasemia beta/tratamiento farmacológico , Talasemia beta/complicaciones , Quelantes del Hierro/uso terapéutico , Niño , Sobrecarga de Hierro/tratamiento farmacológico , Sobrecarga de Hierro/etiología , Terapia por Quelación/métodos , Preescolar , Deferoxamina/uso terapéutico , Deferiprona/uso terapéutico , Piridonas/uso terapéutico , Piridonas/efectos adversosRESUMEN
BACKGROUND: Patients with transfusion-dependent ß-thalassemia need regular red-cell transfusions. Luspatercept, a recombinant fusion protein that binds to select transforming growth factor ß superfamily ligands, may enhance erythroid maturation and reduce the transfusion burden (the total number of red-cell units transfused) in such patients. METHODS: In this randomized, double-blind, phase 3 trial, we assigned, in a 2:1 ratio, adults with transfusion-dependent ß-thalassemia to receive best supportive care plus luspatercept (at a dose of 1.00 to 1.25 mg per kilogram of body weight) or placebo for at least 48 weeks. The primary end point was the percentage of patients who had a reduction in the transfusion burden of at least 33% from baseline during weeks 13 through 24 plus a reduction of at least 2 red-cell units over this 12-week interval. Other efficacy end points included reductions in the transfusion burden during any 12-week interval and results of iron studies. RESULTS: A total of 224 patients were assigned to the luspatercept group and 112 to the placebo group. Luspatercept or placebo was administered for a median of approximately 64 weeks in both groups. The percentage of patients who had a reduction in the transfusion burden of at least 33% from baseline during weeks 13 through 24 plus a reduction of at least 2 red-cell units over this 12-week interval was significantly greater in the luspatercept group than in the placebo group (21.4% vs. 4.5%, P<0.001). During any 12-week interval, the percentage of patients who had a reduction in transfusion burden of at least 33% was greater in the luspatercept group than in the placebo group (70.5% vs. 29.5%), as was the percentage of those who had a reduction of at least 50% (40.2% vs. 6.3%). The least-squares mean difference between the groups in serum ferritin levels at week 48 was -348 µg per liter (95% confidence interval, -517 to -179) in favor of luspatercept. Adverse events of transient bone pain, arthralgia, dizziness, hypertension, and hyperuricemia were more common with luspatercept than placebo. CONCLUSIONS: The percentage of patients with transfusion-dependent ß-thalassemia who had a reduction in transfusion burden was significantly greater in the luspatercept group than in the placebo group, and few adverse events led to the discontinuation of treatment. (Funded by Celgene and Acceleron Pharma; BELIEVE ClinicalTrials.gov number, NCT02604433; EudraCT number, 2015-003224-31.).
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Receptores de Activinas Tipo II/uso terapéutico , Transfusión de Eritrocitos/estadística & datos numéricos , Hematínicos/uso terapéutico , Fragmentos Fc de Inmunoglobulinas/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéutico , Talasemia beta/tratamiento farmacológico , Receptores de Activinas Tipo II/efectos adversos , Adolescente , Adulto , Anciano , Método Doble Ciego , Femenino , Ferritinas/sangre , Hematínicos/efectos adversos , Humanos , Fragmentos Fc de Inmunoglobulinas/efectos adversos , Análisis de Intención de Tratar , Análisis de los Mínimos Cuadrados , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Proteínas Recombinantes de Fusión/efectos adversos , Esplenectomía , Adulto Joven , Talasemia beta/genética , Talasemia beta/cirugía , Talasemia beta/terapiaRESUMEN
CALYPSO (NCT02435212), a randomized, open-label, multicenter, phase 2 study evaluated the compliance, clinical benefits, and safety of deferasirox granules and dispersible tablets in pediatric patients with iron overload. Iron chelation therapy-naive and iron chelation therapy-pre-treated patients aged 2 to 0.5 mg/mg; 24.5% and 34.2%), upper respiratory tract infection (28.2% and 29.7%), and pyrexia (26.4% and 23.4%). In iron chelation therapy-naive patients, mean compliance and change from baseline in serum ferritin with both deferasirox formulations were not significantly different. The safety profile was comparable between granule and dispersible tablets formulations, and was consistent with the general safety profile of deferasirox.
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Iron chelation therapy (ICT) is the mainstay of treatment in patients with thalassemia requiring blood transfusions. This phase 2 JUPITER study evaluated patient preference between film-coated tablet (FCT) and dispersible tablet (DT) in transfusion-dependent thalassemia (TDT) or non-TDT (NTDT) patients treated with both formulations in a sequential manner. The primary endpoint was patient-reported preference for FCT over DT, while secondary outcomes included patient reported outcomes (PROs) evaluated by overall preference, and by age, thalassemia transfusion status, and previous ICT status. Out of 183 patients screened, 140 and 136 patients completed the treatment periods 1 and 2 of the core study, respectively. At week 48, the majority of patients preferred FCT over DT (90.3 vs. 7.5%; difference of percentage: 0.83 [95% confidence interval (CI), 0.75-0.89; P < 0.0001]). FCT scored better on secondary PROs and showed less severe gastrointestinal symptoms than DT, except in the change of modified Satisfaction with Iron Chelation Therapy (mSICT) preference scores, which were similar for both the formulations. Patients with TDT had stable ferritin levels, while it showed a downward trend up to week 48 in patients with NTDT on deferasirox treatment. Overall, 89.9% of patients reported ≥ 1 adverse event (AE), of which 20.3% experienced ≥ 1 serious AE. The most common treatment-emergent AEs were proteinuria, pyrexia, urine protein/creatinine ratio increase, diarrhea, upper respiratory tract infections, transaminase increase, and pharyngitis. Overall, this study reinforced the observations from the previous study by showing a distinct patient preference for FCT over DT formulation and further supported the potential benefits of life-long compliance with ICT.
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Sobrecarga de Hierro , Talasemia , Humanos , Deferasirox , Sobrecarga de Hierro/complicaciones , Prioridad del Paciente , Talasemia/tratamiento farmacológico , Comprimidos , Hierro , Quelantes del Hierro/efectos adversos , Benzoatos/efectos adversosRESUMEN
BACKGROUND: Patients with transfusion-dependent (TD) ß-thalassemia require long-term red blood cell transfusions (RBCTs) that lead to iron overload, impacting health-related quality of life (HRQoL). METHODS: The impact of luspatercept, a first-in-class erythroid maturation agent, versus placebo on HRQoL of patients with TD ß-thalassemia was evaluated in the phase 3 BELIEVE trial. HRQoL was assessed at baseline and every 12 weeks using the 36-item Short Form Health Survey (SF-36) and Transfusion-dependent Quality of Life questionnaire (TranQol). Mean change in HRQoL was evaluated from baseline to week 48 for patients receiving luspatercept + best supportive care (BSC) and placebo + BSC and between luspatercept responders and non-responders. RESULTS: Through week 48, for both groups, mean scores on SF-36 and TranQol domains were stable over time and did not have a clinically meaningful change. At week 48, more patients who achieved clinical response (≥50% reduction in RBCT burden over 24 weeks) in the luspatercept + BSC group had improvement in SF-36 Physical Function compared with placebo + BSC (27.1% vs. 11.5%; p = .019). CONCLUSIONS: Luspatercept + BSC reduced transfusion burden while maintaining patients' HRQoL. HRQoL domain improvements from baseline through 48 weeks were also enhanced for luspatercept responders.
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Talasemia beta , Humanos , Receptores de Activinas Tipo II/uso terapéutico , Talasemia beta/tratamiento farmacológico , Fragmentos Fc de Inmunoglobulinas/uso terapéutico , Calidad de VidaRESUMEN
BACKGROUND: Children with ß-thalassemia major and ß-thalassemia intermedia frequently have low bone mass. However, studies of bone mineral density (BMD) in children with transfusion-dependent (TD) or non-transfusion-dependent (NTD) hemoglobin (Hb) E/ß-thalassemia are scarce. OBJECTIVES: To determine the prevalence of low bone mass among mostly preadolescent children with NTD and TD Hb E/ß thalassemia and the related factors. METHODS: We investigated the BMD of the lumbar spine (LSBMD) and total body (TBBMD), measured by dual-energy X-ray absorptiometry, of 59 children with NTD Hb E/ß-thalassemia and 50 with TD Hb E/ß-thalassemia. RESULTS: The median age of the patients was 10.4 (6.2-13.5) years in the NTD group and 10.3 (5.9-14.1) years in the TD group. These children had a relatively low prevalence of low bone mass (NTD: 1.7%-10.2%; TD: 4%-14%). The values varied with the bone site measured and the BMD size-adjustment method used (height age vs. bone age). The NTD group had significantly lower TBBMD Z-scores (adjusted for height age) than the TD group. The proportion of patients with low lumbar spine bone mass (adjusted for bone age) was significantly higher for the TD group than for the NTD group. CONCLUSIONS: Our study demonstrates that most children with either disease had normal BMD. Patients with the NTD form had a lower TBBMD than those with the TD form. Low bone mass affected the lumbar spine of patients with TD Hb E/ß-thalassemia more than those with the NTD form.
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Hemoglobina E , Talasemia , Talasemia beta , Absorciometría de Fotón , Adolescente , Densidad Ósea , Niño , Humanos , Talasemia beta/terapiaRESUMEN
Mutations in the KLF1 gene, which encodes a transcription factor playing a role in erythropoiesis, have recently been demonstrated to be a rare cause of hereditary haemolytic anaemia. We described the genotypic and phenotypic spectra of four unrelated families with compound heterozygous class 2/class 3 KLF1 mutations. All patients had p.G176RfsX179 on one allele and either p.A298P, p.R301H or p.G335R on the other allele. All presented on the first day of life with severe haemolytic anaemia with abnormal red blood cell morphology, markedly increased nucleated red blood cells and hyperbilirubinaemia. Three patients later became transfusion-dependent. All parents with heterozygous KLF1 mutation without co-inherited thalassaemia had normal to borderline mean corpuscular volume (MCV) and normal to slightly elevated Hb F. Fifteen previously reported cases of biallelic KLF1 mutations were identified from a literature review. All except one presented with severe haemolytic anaemia in the neonatal period. Our finding substantiates that compound heterozygous KLF1 mutations are associated with severe neonatal haemolytic anaemia and expands the haematologic phenotypic spectrum. In carriers, the previously suggested findings of low MCV, high Hb A2 and high Hb F are inconsistent; thus this necessitates molecular studies for the identification of carriers.
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Anemia Hemolítica/genética , Factores de Transcripción de Tipo Kruppel/genética , Mutación Puntual , Adolescente , Adulto , Anemia Hemolítica/diagnóstico , Anemia Hemolítica/patología , Niño , Preescolar , Femenino , Heterocigoto , Humanos , Lactante , Recién Nacido , Masculino , Mutación , Linaje , Adulto JovenRESUMEN
BACKGROUND: To estimate median liver iron concentration (LIC) calculated from magnetic resonance imaging, excluded vessels of the liver parenchyma region were defined manually. Previous works proposed the automated method for excluding vessels from the liver region. However, only user-defined liver region remained a manual process. Therefore, this work aimed to develop an automated liver region segmentation technique to automate the whole process of median LIC calculation. METHODS: 553 MR examinations from 471 thalassemia major patients were used in this study. LIC maps (in mg/g dry weight) were calculated and used as the input of segmentation procedures. Anatomical landmark data were detected and used to restrict ROI. After that, the liver region was segmented using fuzzy c-means clustering and reduced segmentation errors by morphological processes. According to the clinical application, erosion with a suitable size of the structuring element was applied to reduce the segmented liver region to avoid uncertainty around the edge of the liver. The segmentation results were evaluated by comparing with manual segmentation performed by a board-certified radiologist. RESULTS: The proposed method was able to produce a good grade output in approximately 81% of all data. Approximately 11% of all data required an easy modification step. The rest of the output, approximately 8%, was an unsuccessful grade and required manual intervention by a user. For the evaluation matrices, percent dice similarity coefficient (%DSC) was in the range 86-92, percent Jaccard index (%JC) was 78-86, and Hausdorff distance (H) was 14-28 mm, respectively. In this study, percent false positive (%FP) and percent false negative (%FN) were applied to evaluate under- and over-segmentation that other evaluation matrices could not handle. The average of operation times could be reduced from 10 s per case using traditional method, to 1.5 s per case using our proposed method. CONCLUSION: The experimental results showed that the proposed method provided an effective automated liver segmentation technique, which can be applied clinically for automated median LIC calculation in thalassemia major patients.
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Lógica Difusa , Interpretación de Imagen Asistida por Computador/métodos , Hierro/análisis , Hígado/química , Imagen por Resonancia Magnética , Reconocimiento de Normas Patrones Automatizadas , Talasemia beta/diagnóstico por imagen , Adolescente , Algoritmos , Femenino , Humanos , Hígado/anatomía & histología , Hígado/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Masculino , Adulto JovenRESUMEN
BACKGROUND: Thalassemia, an inherited hemoglobin disorder, has become a global public health problem due to population migration. Evidence-based strategies for thalassemia prevention in migrants are lacking. We characterized barriers to thalassemia screening and the burden of thalassemia in migrant workers in Thailand. METHODS: Multilingual demographic and KAP surveys were completed by 197 Thai, 119 Myanmar, and 176 Cambodian adults residing in Thailand. Thalassemia awareness, socio-demographic predictors, and knowledge and attitude scores were compared between migrant and Thai subjects. Comprehensive thalassemia testing was performed for migrants. RESULTS: Migrants had extremely poor thalassemia awareness (4.1%) compared to Thai subjects (79.6%) and had lower thalassemia knowledge scores but similar attitude scores. Surveys identified differing sociodemographic factors predicting awareness in Thai and migrant subjects, as well as key misconceptions likely to hinder thalassemia screening uptake. Nearly all migrants consented to thalassemia testing. We identified abnormal hemoglobin profiles in 52.7% of migrants and a higher projected rate of severe thalassemia births in migrants. CONCLUSIONS: The high burden of thalassemia and tremendous knowledge gap in migrants needs urgent attention. Thalassemia screening was feasible and acceptable in our migrant population. Sociocultural and structural barriers merit further attention when designing thalassemia screening and prevention policies for migrants in Thailand and globally.
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Migrantes , Adulto , Pueblo Asiatico , Estudios Transversales , Estudios de Factibilidad , Humanos , Mianmar , TailandiaRESUMEN
BACKGROUND: Thalassemia is a common inherited hemoglobin disorder in Southeast Asia. Severe thalassemia can lead to significant morbidity for patients and economic strain for under-resourced health systems. Thailand's thalassemia prevention and control program has successfully utilized prenatal screening and diagnosis to reduce the incidence of severe thalassemia in Thai populations, but migrant populations are excluded despite having high thalassemia prevalence. We sought to identify key barriers to and facilitators of thalassemia screening and to develop tailored recommendations for providing migrants with access to thalassemia prevention and control. METHODS: We conducted 28 in-depth interviews and 4 focus group discussions (FGDs) in Chonburi, Thailand with Myanmar and Cambodian migrants, Thai healthcare providers, Thai parents of children affected by thalassemia, and migrant agents. RESULTS: Participant narratives revealed that migrants' lack of knowledge about the prevalence, manifestations, severity, and inherited nature of thalassemia led to misconceptions, fear, or indifference toward thalassemia and screening. Negative perceptions of pregnancy termination were based in religious beliefs but compounded by other sociocultural factors, presenting a key obstacle to migrant uptake of prenatal screening. Additionally, structural barriers included legal status, competing work demands, lack of health insurance, and language barriers. Participants recommended delivering public thalassemia education in migrants' native languages, implementing carrier screening, and offering thalassemia screening in convenient settings. CONCLUSIONS: An effective thalassemia prevention and control program should offer migrants targeted thalassemia education and outreach, universal coverage for thalassemia screening and prenatal care, and options for carrier screening, providing a comprehensive strategy for reducing the incidence of severe thalassemia in Thailand and establishing an inclusive model for regional thalassemia prevention and control.
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Migrantes , Niño , Accesibilidad a los Servicios de Salud , Humanos , Tamizaje Masivo , Tailandia , Cobertura Universal del Seguro de SaludRESUMEN
BACKGROUND: Iron overload is a major complication of transfusion-dependent thalassemia (TDT) and requires iron chelation (IC) therapy. However, a combination therapy may be required for patients responding poorly to monotherapy. METHODS: Nine TDT patients previously treated with IC were enrolled; five patients were previously treated with deferasirox (DFX) twice daily. The dose of DFX was 20-40 mg/kg/day, while the dose of deferoxamine (DFO) was 18-40 mg/kg/day for 3-6 days/week. RESULTS: At the 6- and 12-month time points, six and eight patients demonstrated decreased serum ferritin levels, with median reductions of 707 ng/mL (range, 1,653-5,444 ng/mL) and 1,129 ng/mL (range, 1,781-7,725 ng/mL) compared to the baseline, respectively. Eight patients also had a reduced liver iron concentration (LIC), with a median reduction of 3.9 mg/g dry wt (range, 8.3-11.1 mg/g dry wt). Of the five patients treated with DFX twice daily, four responded to combination therapy. All responsive patients could finally stop DFO after the decline in LIC. Moreover, there were no treatment-related complications. CONCLUSION: The combination of DFX and DFO proved to be effective and without significant toxicities for TDT patients who had been unresponsive to standard IC therapy. Further studies with a larger cohort size and long-term follow-up are warranted to elucidate the efficacy of the combination.
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Sobrecarga de Hierro , Talasemia , Talasemia beta , Benzoatos/uso terapéutico , Deferasirox , Deferoxamina/uso terapéutico , Humanos , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro/tratamiento farmacológico , Sobrecarga de Hierro/etiología , Talasemia/complicaciones , Talasemia/tratamiento farmacológico , Triazoles/uso terapéuticoRESUMEN
ß-thalassemia major is an inherited hemoglobinopathy that requires lifelong red blood cell transfusions and iron chelation therapy to prevent complications due to iron overload. Traditionally, ß-thalassemia has been more common in certain regions of the world such as the Mediterranean, Middle East, and Southeast Asia. However, the prevalence of ß-thalassemia is increasing in other regions, including Northern Europe and North America, primarily due to migration. This review summarizes the available data on the changing incidence and prevalence of ß-thalassemia as well as factors influencing disease frequency. The data suggest that the epidemiology of ß-thalassemia is changing: Migration has increased the prevalence of the disease in regions traditionally believed to have a low prevalence, while, at the same time, prevention and screening programs in endemic regions have reduced the number of affected individuals. Various approaches to prevention and screening have been used. Region-specific prevention and treatment programs, customized to align with local healthcare resources and cultural values, have been effective in identifying patients and carriers and providing information and care. Significant challenges remain in universally implementing these programs.
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Talasemia beta/epidemiología , Manejo de la Enfermedad , Susceptibilidad a Enfermedades , Emigración e Inmigración , Geografía Médica , Salud Global , Humanos , Incidencia , Vigilancia de la Población , Prevalencia , Vigilancia en Salud Pública , Factores de Riesgo , Talasemia beta/diagnóstico , Talasemia beta/etiología , Talasemia beta/prevención & controlRESUMEN
Nearly 7% of the world's population live with a hemoglobin variant. Hemoglobins S, C, and E are the most common and significant hemoglobin variants worldwide. Sickle cell disease, caused by hemoglobin S, is highly prevalent in sub-Saharan Africa and in tribal populations of Central India. Hemoglobin C is common in West Africa, and hemoglobin E is common in Southeast Asia. Screening for significant hemoglobin disorders is not currently feasible in many low-income countries with the high disease burden. Lack of early diagnosis leads to preventable high morbidity and mortality in children born with hemoglobin variants in low-resource settings. Here, we describe HemeChip, the first miniaturized, paper-based, microchip electrophoresis platform for identifying the most common hemoglobin variants easily and affordably at the point-of-care in low-resource settings. HemeChip test works with a drop of blood. HemeChip system guides the user step-by-step through the test procedure with animated on-screen instructions. Hemoglobin identification and quantification is automatically performed, and hemoglobin types and percentages are displayed in an easily understandable, objective way. We show the feasibility and high accuracy of HemeChip via testing 768 subjects by clinical sites in the United States, Central India, sub-Saharan Africa, and Southeast Asia. Validation studies include hemoglobin E testing in Bangkok, Thailand, and hemoglobin S testing in Chhattisgarh, India, and in Kano, Nigeria, where the sickle cell disease burden is the highest in the world. Tests were performed by local users, including healthcare workers and clinical laboratory personnel. Study design, methods, and results are presented according to the Standards for Reporting Diagnostic Accuracy (STARD). HemeChip correctly identified all subjects with hemoglobin S, C, and E variants with 100% sensitivity, and displayed an overall diagnostic accuracy of 98.4% in comparison to reference standard methods. HemeChip is a versatile, mass-producible microchip electrophoresis platform that addresses a major unmet need of decentralized hemoglobin analysis in resource-limited settings.
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Electroforesis por Microchip/métodos , Hemoglobinas/análisis , Papel , Hemoglobina Falciforme/análisis , Humanos , Procesamiento de Imagen Asistido por Computador , Miniaturización , Sistemas de Atención de Punto , Interfaz Usuario-ComputadorRESUMEN
BACKGROUND: Diabetes mellitus (DM) associated with iron overload has been reported among adults with transfusion-dependent thalassemia and those with non-transfusion-dependent thalassemia (NTDT), especially in ß-thalassemia disease. However, little is known about glucose metabolism and how early its dysregulation can develop in α-thalassemia hemoglobin H (Hb H) disease, which is one of the most common types of NTDT worldwide. PROCEDURE: We prospectively calculated glucose metabolism index in 40 patients (aged 10-25 years) with Hb H disease. Glucose metabolism data were compared between patients with deletional versus nondeletional Hb H, and between patients with normal versus abnormal insulin secretion/sensitivity. RESULTS: Despite normal glucose tolerance in all patients, 52.5% had abnormal insulinogenic index indicating decreased ß-cell insulin secretion. Patients with functional hemoglobin < 8 g/dL had significantly higher percentages of abnormal insulinogenic index. There was no significant difference in abnormal insulinogenic index between deletional and nondeletional Hb H. CONCLUSION: Decreased ß-cell insulin secretion is highly prevalent among children and adolescents with Hb H disease, and it is associated with levels of functional anemia at baseline, but not with the type of Hb H disease. This result warrants heightened awareness among hematologists due to potentially increased risk of DM later in life.
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Anemia/etiología , Secreción de Insulina , Talasemia alfa/complicaciones , Talasemia alfa/metabolismo , Adolescente , Adulto , Niño , Femenino , Glucosa/metabolismo , Humanos , Células Secretoras de Insulina/metabolismo , Masculino , Adulto JovenRESUMEN
BACKGROUND: The role of splenectomy prior to hematopoietic stem cell transplantation (HSCT) is controversial. Only few studies compared the outcomes of splenectomized and nonsplenectomized children with transfusion-dependent thalassemia (TDT) undergoing allogeneic HSCTs. METHODS: A retrospective analysis was undertaken on a transplantation cohort of TDT patients; August 1987-December 2014 to compare transplant outcomes between splenectomized and nonsplenectomized groups. RESULTS: Ninety-six transplants in 86 TDT patients were analyzed. Sixteen patients were splenectomized before HSCTs. The splenectomized patients were significantly older (8.0 ± 1.9 vs 4.7 ± 0.6 years; P = 0.001), had larger livers and spleens (P = 0.001), and had a significantly shorter neutrophil engraftment time (absolute neutrophil count > 500/mm3 ; 15.0 ± 2.3 vs 19.2 ± 1.3 days; P = 0.004). Graft rejection occurred in 13.8% of the nonsplenectomized group, but not among the splenectomized patients. Though the splenectomized group's mortality rate was higher (25.0% vs 8.8%), this was not statistically significant (P = 0.491). The main causes of death in both groups were severe infections. The five-year overall survival (OS) rate was better for the nonsplenectomized group (91.78% vs 75.00%; P = 0.06). CONCLUSIONS: Although splenectomies prior to HSCT for the TDT patients in our cohort were associated with faster neutrophil engraftments and lower rejection rates, they did not produce significantly better OS or affect the mortality. As the splenectomies did not provide any distinct advantages, this procedure should not be routinely performed as a pre-HSCT regimen for TDT patients with splenomegaly. Better pre-HSCT preparation for TDT patients, including early and adequate blood transfusions to avoid splenomegaly, is recommended.
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Rechazo de Injerto/mortalidad , Trasplante de Células Madre Hematopoyéticas , Sistema de Registros , Esplenectomía , Talasemia/mortalidad , Talasemia/terapia , Adolescente , Aloinjertos , Transfusión Sanguínea , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
This study demonstrates the quantitative characteristics of the first patient-reported outcome (PRO) tool developed for patients with nontransfusion-dependent ß-thalassemia (NTDT), the NTDT-PRO© . A multicenter validation study was performed over 24 weeks, involving 48 patients from Italy, Lebanon, Greece, and Thailand. Most patients were female (68.8%), with a median age of 34.5 years (range, 18-52); 66.7% were diagnosed with ß-thalassemia intermedia, and median time since diagnosis was 22 years (range, 0-43). The NTDT-PRO comprises 6 items across 2 domains (Tiredness/Weakness and Shortness of Breath [SoB]), and was valid and reliable, with good consistency. At baseline, most patients reported symptoms as present via the NTDT-PRO, and were highly compliant, ≥90% completing the NTDT-PRO tool. In a pairwise correlation analysis, all items were positively correlated. Correlations between NTDT-PRO and existing tools-36-Item Short Form Health Survey version 2 (SF-36v2) and Functional Assessment of Cancer Therapy-Anemia (FACT-An)-were assessed at weeks 1, 3, and 12; robust correlations were seen between SoB and SF-36v2-Vitality (rs = -0.53), and between SoB and Fact-An-Fatigue Experience (rs = -0.66) at week 1. Internal consistency was high for both Tiredness/Weakness (Cronbach alpha, 0.91) and SoB (Spearman-Brown coefficient, 0.78); intraclass correlation coefficients were high (Tiredness/Weakness, 0.88 and 0.97; SoB, 0.92 and 0.98), demonstrating stability. Further studies are required to fully support the validity of this tool, this study demonstrated the usefulness of the NTDT-PRO in the clinical setting and for longitudinal clinical research, particularly in trials where patient health-related quality of life is expected to change.
Asunto(s)
Medición de Resultados Informados por el Paciente , Talasemia beta/patología , Adolescente , Adulto , Disnea , Fatiga , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Calidad de Vida , Adulto JovenRESUMEN
ß-Thalassemia, a hereditary blood disorder caused by reduced or absent synthesis of the ß-globin chain of hemoglobin, is characterized by ineffective erythropoiesis, and can manifest as nontransfusion-dependent thalassemia (NTDT) or transfusion-dependent thalassemia (TDT). Many patients with NTDT develop a wide range of serious complications that affect survival and quality of life (QoL). Patient-reported outcomes (PRO), including health-related QoL (HRQoL), are important tools for determining patient health impairment and selecting appropriate treatment. However, there are currently no disease-specific PRO tools available to assess symptoms related to chronic anemia experienced by patients with NTDT. This study aimed to develop a new, US Food and Drug Administration (FDA)-compliant PRO of chronic anemia symptoms, the NTDT-PRO© tool, for use in patients with NTDT. Participants had a median age of 36 years (range, 18-47) and 60% were female. The initial development of the NTDT-PRO tool involved concept-elicitation interviews with 25 patients from 3 centers (in Lebanon, Greece, and Canada); subsequent interview discussions and clinical input resulted in the generation of 9 items for inclusion in the draft NTDT-PRO. Following a round of cognitive interviews involving 21 patients from 2 centers (in Lebanon and Greece), 4 items (Pain, Headaches, Ability to Concentrate, and Paleness) were removed from the draft NTDT-PRO. The final NTDT-PRO comprises 6 items that measure Tiredness, Weakness, and Shortness of Breath, with or without Physical Activity. The NTDT-PRO is a new disease-specific HRQoL tool for patients with NTDT, developed using a thorough methodology based on FDA 2009 PRO development guidelines.