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1.
Blood ; 143(4): 357-369, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38033286

RESUMO

ABSTRACT: Cell-surface exposure of phosphatidylserine (PS) is essential for phagocytic clearance and blood clotting. Although a calcium-activated phospholipid scramblase (CaPLSase) has long been proposed to mediate PS exposure in red blood cells (RBCs), its identity, activation mechanism, and role in RBC biology and disease remain elusive. Here, we demonstrate that TMEM16F, the long-sought-after RBC CaPLSase, is activated by calcium influx through the mechanosensitive channel PIEZO1 in RBCs. PIEZO1-TMEM16F functional coupling is enhanced in RBCs from individuals with hereditary xerocytosis (HX), an RBC disorder caused by PIEZO1 gain-of-function channelopathy. Enhanced PIEZO1-TMEM16F coupling leads to an increased propensity to expose PS, which may serve as a key risk factor for HX clinical manifestations including anemia, splenomegaly, and postsplenectomy thrombosis. Spider toxin GsMTx-4 and antigout medication benzbromarone inhibit PIEZO1, preventing force-induced echinocytosis, hemolysis, and PS exposure in HX RBCs. Our study thus reveals an activation mechanism of TMEM16F CaPLSase and its pathophysiological function in HX, providing insights into potential treatment.


Assuntos
Anemia Hemolítica Congênita , Cálcio , Feminino , Humanos , Anemia Hemolítica Congênita/genética , Cálcio/metabolismo , Eritrócitos/metabolismo , Hidropisia Fetal/genética , Canais Iônicos/genética , Proteínas de Transferência de Fosfolipídeos/genética
2.
MMWR Morb Mortal Wkly Rep ; 73(12): 248-254, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38547025

RESUMO

Sickle cell disease (SCD) remains a public health priority in the United States because of its association with complex health needs, reduced life expectancy, lifelong disabilities, and high cost of care. A cross-sectional analysis was conducted to calculate the crude and race-specific birth prevalence for SCD using state newborn screening program records during 2016-2020 from 11 Sickle Cell Data Collection program states. The percentage distribution of birth mother residence within Social Vulnerability Index quartiles was derived. Among 3,305 newborns with confirmed SCD (including 57% with homozygous hemoglobin S or sickle ß-null thalassemia across 11 states, 90% of whom were Black or African American [Black], and 4% of whom were Hispanic or Latino), the crude SCD birth prevalence was 4.83 per 10,000 (one in every 2,070) live births and 28.54 per 10,000 (one in every 350) non-Hispanic Black newborns. Approximately two thirds (67%) of mothers of newborns with SCD lived in counties with high or very high levels of social vulnerability; most mothers lived in counties with high or very high levels of vulnerability for racial and ethnic minority status (89%) and housing type and transportation (64%) themes. These findings can guide public health, health care systems, and community program planning and implementation that address social determinants of health for infants with SCD. Implementation of tailored interventions, including increasing access to transportation, improving housing, and advancing equity in high vulnerability areas, could facilitate care and improve health outcomes for children with SCD.


Assuntos
Anemia Falciforme , Etnicidade , Feminino , Criança , Humanos , Recém-Nascido , Estados Unidos/epidemiologia , Prevalência , Estudos Transversais , Vulnerabilidade Social , Grupos Minoritários , Anemia Falciforme/epidemiologia , Anemia Falciforme/diagnóstico
3.
Am J Hematol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953438

RESUMO

Central nervous system (CNS) injury is common in sickle cell disease (SCD) and occurs early in life. Hydroxyurea is safe and efficacious for treatment of SCD, but high-quality evidence from randomized trials to estimate its neuroprotective effect is scant. HU Prevent was a randomized (1:1), double-blind, phase II feasibility/pilot trial of dose-escalated hydroxyurea vs. placebo for the primary prevention of CNS injury in children with HbSS or HbS-ß0-thalassemia subtypes of SCD age 12-48 months with normal neurological examination, MRI of the brain, and cerebral blood flow velocity. We hypothesized that hydroxyurea would reduce by 50% the incidence of CNS injury. Two outcomes were compared: primary-a composite of silent cerebral infarction, elevated cerebral blood flow velocity, transient ischemic attack, or stroke; secondary-a weighted score estimating the risk of suffering the consequences of stroke (the Stroke Consequences Risk Score-SCRS), based on the same outcome events. Six participants were randomized to each group. One participant in the hydroxyurea group had a primary outcome vs. four in the placebo group (incidence rate ratio [90% CI] 0.216 [0.009, 1.66], p = .2914) (~80% reduction in the hydroxyurea group). The mean SCRS score was 0.078 (SD 0.174) in the hydroxyurea group, 0.312 (SD 0.174) in the placebo group, p = .072, below the p-value of .10 often used to justify subsequent phase III investigations. Serious adverse events related to study procedures occurred in 3/41 MRIs performed, all related to sedation. These results suggest that hydroxyurea may have profound neuroprotective effect in children with SCD and support a definitive phase III study to encourage the early use of hydroxyurea in all infants with SCD.

4.
Stroke ; 53(11): e463-e466, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36205141

RESUMO

BACKGROUND: Hemorrhagic stroke in young patients with sickle cell anemia remains poorly characterized. METHODS: The Post-STOP (Stroke Prevention Trial in Sickle Cell Anemia) retrospective study collected follow-up data on STOP and STOP II clinical trial cohorts. From January 2012 to May 2014, a team of analysts abstracted data from medical records of prior participants (all with sickle cell anemia). Two vascular neurologists reviewed data to confirm hemorrhagic strokes defined as spontaneous intracerebral, subarachnoid, or intraventricular hemorrhage. Incidence rates were calculated using survival analysis techniques Results: Follow-up data were collected from 2850 of 3835 STOP or STOP II participants. Patients (51% male) were a median of 19.1 (interquartile range, 16.6-22.6) years old at the time of last known status. The overall hemorrhagic stroke incidence rate was 63 per 100 000 person-years (95% CI, 45-87). Stratified by age, the incidence rate per 100 000 person-years was 50 (95% CI, 34-75) for children and 134 (95% CI, 74-243) for adults >18 years. Vascular abnormalities (moyamoya arteriopathy, aneurysm or cavernous malformation) were identified in 18 of 35 patients with hemorrhagic stroke. CONCLUSIONS: The incidence rate of hemorrhagic stroke in patients with sickle cell anemia increases with age. Structural vascular abnormalities such as moyamoya arteriopathy and aneurysms are common etiologies for hemorrhage and screening may be warranted.


Assuntos
Anemia Falciforme , Acidente Vascular Cerebral Hemorrágico , Adolescente , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Anemia Falciforme/epidemiologia , Acidente Vascular Cerebral Hemorrágico/epidemiologia , Doença de Moyamoya/epidemiologia , Estudos Retrospectivos , Ensaios Clínicos como Assunto
5.
Pediatr Blood Cancer ; 69(10): e29877, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35856776

RESUMO

BACKGROUND: Adolescent and young adult (AYA) women with sickle cell disease (SCD) have increased pregnancy-related health risks and are prescribed potentially teratogenic medications, yet limited data are available regarding pediatric SCD provider contraceptive practices. We aimed to assess pediatric hematology providers' beliefs, practices, motivators, and barriers for providing contraceptive care to female AYAs with SCD. METHODS: Guided by the Health Belief Model (HBM), we developed a 25-question, web-based survey to assess practices. Survey links were distributed nationwide to pediatric SCD and/or general hematology providers through their publicly available emails and by request to directors of U.S.-accredited Pediatric Hematology-Oncology fellowship programs for distribution to their SCD providers. Data analysis included descriptive statistics, chi-square analysis, and logistic regression. RESULTS: Of 177 respondents, 160 surveys meeting inclusion criteria were analyzed. Most providers reported counseling (77.5%) and referring female AYA patients for contraception (90.8%), but fewer reported prescribing contraception (41.8%). Proportionally fewer trainees provided counseling compared with established providers (54% vs. 85%, p < .001), with a similar trend for prescribing (p = .05). Prescription practices did not differ significantly by provider beliefs regarding potential teratogenicity of hydroxyurea. Key motivators included patient request and disclosure of sexual activity. Key barriers included inadequate provider training, limited visit time, and perceived patient/parent interest. CONCLUSION: Provider contraceptive practices for female AYAs with SCD varied, especially by provider status. Health beliefs regarding teratogenic potential of hydroxyurea did not correlate with contraceptive practices. Clinical guidelines, provider training, and patient/parent decision-making tools may be tested to assess whether provider contraceptive practices could be improved.


Assuntos
Anemia Falciforme , Hematologia , Adolescente , Criança , Anticoncepção/psicologia , Anticoncepcionais , Feminino , Humanos , Hidroxiureia , Gravidez , Adulto Jovem
6.
Omega (Westport) ; : 302228221116513, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35857485

RESUMO

The life-limiting and unpredictable nature of sickle cell disease (SCD) is well-established, yet there is limited literature on end-of-life planning. The purpose of this study was to describe perspectives about preparing for death for older adults with SCD. We enrolled 19 older adults with SCD (age ≥ 50 years) into this qualitative descriptive study. Theme 1 was "anticipation of early death," with sub-themes: (a) informed of early death and (b) making plans for death. Theme 2 was "near death experiences." Theme 3 was "differences in level of comfort with death" with subthemes: (a) death as a part of life and (b) differences in level of comfort discussing death. Theme 4 was "influence of spirituality" with subthemes: (a) God controls the timing of death and (b) belief in the afterlife. These results will inform interventions to improve the quality of patient-provider communication to provide goal-concordant end-of-life care for adults with SCD.

7.
J Pediatr Hematol Oncol ; 43(3): 104-111, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33560086

RESUMO

INTRODUCTION: Sickle cell disease (SCD) is the most common abnormal genetic blood disease that affects ∼100,000 Americans. Approximately 20% to 37% of children with sickle cell anemia have silent cerebral infarcts by the age of 14 years old. Neurocognitive deficits are identified in infants and preschool children with SCD. The purpose of this systematic literature review is to provide a comprehensive understanding of the prevalence, severity, and the associated risk factors for neurodevelopmental delays (NDDs) in children with SCD 5 years of age and younger. METHODS: Systematic search of 6 databases identified 2467 potentially relevant publications and 8 were identified through a manual search. Only 24 articles met the inclusion criteria. RESULTS: We identified an increased prevalence of NDDs (cognitive, motor, or both). Children experienced deficits with language, attention and behavior, executive functioning, school readiness and/or academic performance, and motor skills (fine and gross motor functioning). Risk factors include silent cerebral infarcts and strokes, SCD genotype (HbSS>HbSC), other biologic, and social factors. CONCLUSION: NDDs are common in children ages 0 to 5 years old with SCD. There is an opportunity to improve adherence to national guideline recommendations and early detection practices by pediatricians, hematologists, and other health care providers.


Assuntos
Anemia Falciforme/complicações , Desenvolvimento Infantil , Desempenho Acadêmico , Atenção , Pré-Escolar , Cognição , Disfunção Cognitiva/etiologia , Deficiências do Desenvolvimento/etiologia , Humanos , Lactente , Destreza Motora , Transtornos do Neurodesenvolvimento/etiologia
8.
Magn Reson Med ; 83(3): 1066-1080, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31483528

RESUMO

PURPOSE: To evaluate different T2 -oxygenation calibrations for estimating venous oxygenation in people with sickle cell anemia (SCA). METHODS: Blood T2 values were measured at 3 T in the internal jugular veins of 12 healthy volunteers and 11 SCA participants with no history of stroke, recent transfusion, or renal impairment. T2 -oxygenation relationships of both sickled and normal blood samples were calibrated individually and compared with values generated from published models. After converting venous T2 values to venous oxygenation, whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen were calculated. RESULTS: Sickle blood samples' oxygenation values calculated from our individual calibrations agreed well with measurements using a blood analyzer, whereas previous T2 calibrations based on normal blood samples showed 13%-19% underestimation. Meanwhile, oxygenation values calculated from previous grouped T2 calibration for sickle blood agreed well with experimental measurement on averaged values, but showed up to 20% variation for several individual samples. Using individual T2 calibrations, the whole-brain oxygen extraction fraction and cerebral metabolic rate of oxygen of SCA participants were 0.38 ± 0.08 and 172 ± 42 µmol/min/100 g, respectively, which were comparable to those values measured on healthy volunteers. CONCLUSION: Our results confirm that sickle blood T2 values not only depend on the hematocrit and oxygenation values, but also on other hematological factors. The individual T2 calibrations minimized the effect of heterogeneity of sickle blood between different SCA populations and improved the accuracy of T2 -based oximetry. The measured oxygen extraction fraction and cerebral metabolic rate of oxygen of this group of SCA participants were found to not differ significantly from those of healthy individuals.


Assuntos
Anemia Falciforme/diagnóstico por imagem , Encéfalo/metabolismo , Imageamento por Ressonância Magnética , Consumo de Oxigênio , Adolescente , Adulto , Algoritmos , Anemia Falciforme/metabolismo , Calibragem , Circulação Cerebrovascular , Feminino , Voluntários Saudáveis , Hematócrito , Humanos , Veias Jugulares/diagnóstico por imagem , Angiografia por Ressonância Magnética , Masculino , Oximetria , Oxigênio/metabolismo , Reprodutibilidade dos Testes , Acidente Vascular Cerebral/fisiopatologia , Adulto Jovem
9.
Pediatr Blood Cancer ; 66(12): e27939, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31429531

RESUMO

The transition period from pediatric care to adult care for patients with sickle cell disease (SCD) is associated with increased mortality and morbidity. Identification of risk factors for unsuccessful transition may aid in developing strategies to improve the transition process and health outcomes in this population. We examined factors associated with unsuccessful transition from pediatric to adult care for patients with SCD at the Johns Hopkins Hospital. We found that public insurance and increased hospitalization rates were associated with poor transition to adult care. The findings provide possible areas of intervention.


Assuntos
Anemia Falciforme/terapia , Transição para Assistência do Adulto/estatística & dados numéricos , Transição para Assistência do Adulto/normas , Adulto , Feminino , Seguimentos , Humanos , Masculino , Prognóstico , Estudos Retrospectivos , Adulto Jovem
10.
Clin Trials ; 16(1): 20-31, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30426764

RESUMO

BACKGROUND: Studies of interventions to prevent the many neurological complications of sickle cell disease must take into account multiple outcomes of variable severity, with limited sample size. The goals of the studies presented were to use investigator preferences across outcomes to determine an attitude-based weighting of relevant clinical outcomes and to establish a valid composite outcome for a clinical trial. METHODS: In Study 1, investigators were surveyed about their practice regarding hydroxyurea therapy and opinions about outcomes for the "Hydroxyurea to Prevent the Central Nervous System Complications of Sickle Cell Disease Trial" (HU Prevent), and their minimally acceptable relative risk reduction for the two outcome components, motor and neurocognitive deficits. In Study 2, HU Prevent investigators provided overall weights for these two components. In Study 3, they provided more granular rankings, ratings, and maximum number acceptable to harm. A weighted composite outcome, the Stroke Consequences Risk Score, was constructed that incorporates the major neurologic complications of sickle cell disease. The Stroke Consequences Risk Score represents the 3-year risk of suffering the adverse consequences of stroke. In Study 4, the results of the Optimizing Primary Stroke Prevention in Sickle Cell Anemia (STOP2) and Silent Infarct Transfusion Trials were reanalyzed in light of the composite outcome. RESULTS: In total, 22 to 27 investigators participated per study. In Study 1, across three samplings between 2009 and 2015, the average minimally acceptable relative risk reduction ranged from 0.36 to 0.50, at or below the target effect size of 0.50. In 2015, 21 (91%) reported that a placebo-controlled trial is reasonable; 23 (100%), that it is ethical; and 22 (96%), that they would change their practice, if the results of the trial were positive. In Studies 2 and 3, the weight elicited for a cognitive decline (of 10 IQ points) from the overall assessment was 0.67 (and for motor deficit, the complementary 0.33); from ranking, 0.6; from rating, 0.58; and from maximal number acceptable to harm, 0.5. Using data from two major clinical trials, Study 4 demonstrated the same conclusions as the original trials using the Stroke Consequences Risk Score, with smaller p-values for both reanalyses. An assessment of acceptability was performed as well. CONCLUSION: This set of studies provides the rationale, justification, and validation for the use of a weighted composite outcome and confirms the need for the phase III HU Prevent study. Surveys of investigators in multi-center studies can provide the basis of clinically meaningful outcomes that foster the translation of study results into practice while increasing the efficiency of a study.


Assuntos
Anemia Falciforme/complicações , Ensaios Clínicos como Assunto , Determinação de Ponto Final/métodos , Avaliação de Resultados em Cuidados de Saúde , Projetos de Pesquisa/normas , Anemia Falciforme/terapia , Criança , Disfunção Cognitiva/prevenção & controle , Humanos , Hidroxiureia/uso terapêutico , Medição de Risco , Índice de Gravidade de Doença , Acidente Vascular Cerebral/prevenção & controle , Inquéritos e Questionários
11.
Hum Brain Mapp ; 39(1): 344-353, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29024300

RESUMO

Baseline hematocrit fraction (Hct) is a determinant for baseline cerebral blood flow (CBF) and between-subject variation of Hct thus causes variation in task-based BOLD fMRI signal changes. We first verified in healthy volunteers (n = 12) that Hct values can be derived reliably from venous blood T1 values by comparison with the conventional lab test. Together with CBF measured using phase-contrast MRI, this noninvasive estimation of Hct, instead of using a population-averaged Hct value, enabled more individual determination of oxygen delivery (DO2 ), oxygen extraction fraction (OEF), and cerebral metabolic rate of oxygen (CMRO2 ). The inverse correlation of CBF and Hct explained about 80% of between-subject variation of CBF in this relatively uniform cohort of subjects, as expected based on the regulation of DO2 to maintain constant CMRO2 . Furthermore, we compared the relationships of visual task-evoked BOLD response with Hct and CBF. We showed that Hct and CBF contributed 22%-33% of variance in BOLD signal and removing the positive correlation with Hct and negative correlation with CBF allowed normalization of BOLD signal with 16%-22% lower variability. The results of this study suggest that adjustment for Hct effects is useful for studies of MRI perfusion and BOLD fMRI. Hum Brain Mapp 39:344-353, 2018. © 2017 Wiley Periodicals, Inc.


Assuntos
Variação Biológica Individual , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Hematócrito , Imageamento por Ressonância Magnética , Oxigênio/sangue , Adulto , Encéfalo/fisiologia , Mapeamento Encefálico , Feminino , Humanos , Modelos Lineares , Masculino , Percepção Visual/fisiologia
13.
Br J Haematol ; 176(2): 300-308, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27766637

RESUMO

'Paradoxical' embolization via intracardiac or intrapulmonary right-to-left shunts (RLS) is an established cause of stroke. Hypercoagulable states and increased right heart pressure, which both occur in sickle cell anaemia (SCA), predispose to paradoxical embolization. We hypothesized that children with SCA and overt stroke (SCA + stroke) have an increased prevalence of potential RLS. We performed contrasted transthoracic echocardiograms on 147 children (aged 2-19 years) with SCA + stroke) mean age 12·7 ± 4·8 years, 54·4% male) and a control group without SCA or stroke (n = 123; mean age 12·1 ± 4·9 years, 53·3% male). RLS was defined as any potential RLS detected by any method, including intrapulmonary shunting. Echocardiograms were masked and adjudicated centrally. The prevalence of potential RLS was significantly higher in the SCA+stroke group than controls (45·6% vs. 23·6%, P < 0·001). The odds ratio for potential RLS in the SCA + stroke group was 2·7 (95% confidence interval: 1·6-4·6) vs controls. In post hoc analyses, the SCA + stroke group had a higher prevalence of intrapulmonary (23·8% vs. 5·7%, P < 0·001) but not intracardiac shunting (21·8% vs. 18·7%, P = 0·533). SCA patients with potential RLS were more likely to report headache at stroke onset than those without. Intrapulmonary and intracardiac shunting may be an overlooked, independent and potentially modifiable risk factor for stroke in SCA.


Assuntos
Anemia Falciforme/complicações , Defeitos dos Septos Cardíacos/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Adolescente , Anemia Falciforme/epidemiologia , Criança , Pré-Escolar , Ecocardiografia , Embolia Paradoxal/etiologia , Feminino , Cefaleia/etiologia , Defeitos dos Septos Cardíacos/complicações , Humanos , Masculino , Prevalência , Fatores de Risco , Adulto Jovem
14.
N Engl J Med ; 371(8): 699-710, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-25140956

RESUMO

BACKGROUND: Silent cerebral infarcts are the most common neurologic injury in children with sickle cell anemia and are associated with the recurrence of an infarct (stroke or silent cerebral infarct). We tested the hypothesis that the incidence of the recurrence of an infarct would be lower among children who underwent regular blood-transfusion therapy than among those who received standard care. METHODS: In this randomized, single-blind clinical trial, we randomly assigned children with sickle cell anemia to receive regular blood transfusions (transfusion group) or standard care (observation group). Participants were between 5 and 15 years of age, with no history of stroke and with one or more silent cerebral infarcts on magnetic resonance imaging and a neurologic examination showing no abnormalities corresponding to these lesions. The primary end point was the recurrence of an infarct, defined as a stroke or a new or enlarged silent cerebral infarct. RESULTS: A total of 196 children (mean age, 10 years) were randomly assigned to the observation or transfusion group and were followed for a median of 3 years. In the transfusion group, 6 of 99 children (6%) had an end-point event (1 had a stroke, and 5 had new or enlarged silent cerebral infarcts). In the observation group, 14 of 97 children (14%) had an end-point event (7 had strokes, and 7 had new or enlarged silent cerebral infarcts). The incidence of the primary end point in the transfusion and observation groups was 2.0 and 4.8 events, respectively, per 100 years at risk, corresponding to an incidence rate ratio of 0.41 (95% confidence interval, 0.12 to 0.99; P=0.04). CONCLUSIONS: Regular blood-transfusion therapy significantly reduced the incidence of the recurrence of cerebral infarct in children with sickle cell anemia. (Funded by the National Institute of Neurological Disorders and Stroke and others; Silent Cerebral Infarct Multi-Center Clinical Trial ClinicalTrials.gov number, NCT00072761, and Current Controlled Trials number, ISRCTN52713285.).


Assuntos
Anemia Falciforme/terapia , Transfusão de Sangue , Infarto Cerebral/prevenção & controle , Adolescente , Anemia Falciforme/complicações , Infarto Cerebral/etiologia , Criança , Pré-Escolar , Feminino , Ferritinas/sangue , Hemoglobina Falciforme/análise , Humanos , Inteligência , Análise de Intenção de Tratamento , Masculino , Prevenção Secundária , Método Simples-Cego , Reação Transfusional
15.
Magn Reson Med ; 77(6): 2296-2302, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27436420

RESUMO

PURPOSE: To develop a fast protocol for measuring T1 values in the internal carotid artery (ICA), to validate this technique with in vitro measurements, and to evaluate its reproducibility. METHODS: A modified Look-Locker sequence was optimized to enable rapid determination of T1 in the ICA at 3T. T1 values from the ICA were compared with in vitro measurements on individually sampled venous blood oxygenated to arterial levels. A test-retest reproducibility study was also conducted. RESULTS: The group-averaged arterial blood T1 value was 1908 ± 77 ms for six women (hematocrit = 0.39 ± 0.03) and 1785 ± 55 ms for seven men (hematocrit = 0.45 ± 0.02), which is 100-200 ms longer than the widely adopted value obtained from bovine blood experiments. The arterial T1 value per subject correlated significantly with individual hematocrit values. The intrasession and intersession coefficients of variation were 1.1% and 2.1%, respectively, indicating good precision and reproducibility of our method. Reasonable agreement was observed between the in vivo and in vitro results with a correlation coefficient of 0.78. CONCLUSION: The proposed method can provide fast arterial T1 measurement on individual subjects. When not performing such a subject-specific measurement, we recommend the use of 1908 ms and 1785 ms for healthy women and men, respectively, or 1841 ms for adults in general. Magn Reson Med 77:2296-2302, 2017. © 2016 International Society for Magnetic Resonance in Medicine.


Assuntos
Velocidade do Fluxo Sanguíneo/fisiologia , Sangue/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/fisiologia , Interpretação de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Processamento de Sinais Assistido por Computador , Adulto , Algoritmos , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Transfusion ; 57(9): 2159-2163, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28707410

RESUMO

BACKGROUND: Factor (F)XIII deficiency is a rare inherited bleeding disorder, but can also be acquired due to the development of inhibitors. CASE REPORT: A 17-year-old female with systemic lupus erythematosus and end-stage kidney disease secondary to Class IV lupus nephritis developed spontaneous subcutaneous and muscular hematomas and delayed major bleeding after invasive procedures. She had abnormal kaolin thromboelastography (kTEG; decreased maximal amplitude, representative of clot strength) initially attributed to thrombocytopenia and uremic platelet dysfunction, but her FXIII activity was undetectable, and a high-titer antibody against FXIII was identified. She had improvement in clinical bleeding and in kaolin thromboelastogram result and transient improvement in FXIII activity after each dose of plasma-derived FXIII concentrate (Corifact) or cryoprecipitate. Her inhibitor titers gradually improved with multiple immunosuppressive therapies and plasma exchange. While her FXIII activity level remained mildly decreased, she has not had additional significant bleeding. CONCLUSION: Treatment with either plasma-derived FXIII or cryoprecipitate is an effective treatment to normalize the kTEG variables and clinical bleeding diatheses associated with acquired FXIII inhibitors. Higher doses may be needed in patients with high-titer inhibitor.


Assuntos
Autoanticorpos/imunologia , Deficiência do Fator XIII/terapia , Fator XIII/imunologia , Adolescente , Fator XIII/uso terapêutico , Deficiência do Fator XIII/etiologia , Deficiência do Fator XIII/imunologia , Feminino , Hematoma , Hemorragia/prevenção & controle , Humanos , Imunossupressores/uso terapêutico , Falência Renal Crônica , Lúpus Eritematoso Sistêmico , Troca Plasmática
17.
Am J Hematol ; 91(3): 313-7, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26690323

RESUMO

Tobacco smoke exposure has been associated with more frequent hospitalizations in children with sickle cell disease (SCD), but previous studies have not quantified the exposure by objective methods. We enrolled 50 children and young adults with SCD in a retrospective and prospective cohort study and quantified tobacco smoke exposure by objective (salivary cotinine) and survey measures. We used a multivariable negative binomial regression model to evaluate the association between salivary cotinine and hospital admissions. Forty-five percent (22/49) of participants had significant elevation of salivary cotinine (≥ 0.5 ng/ml). The incidence risk ratio (IRR) for hospital admission for those with elevated cotinine was 3.7 (95% CI 1.8-8). Those exposed to secondhand smoke but not primary smokers (cotinine between 0.5 and 10 ng/ml) had a similarly increased risk of hospitalization [IRR 4.3 (95% CI 1.8-10)]. We show that an objective measure of tobacco smoke exposure, salivary cotinine, is strongly associated with the rate of hospital admissions in children and young adults with SCD. This association underscores the importance of screening for tobacco smoke exposure in people with SCD. Further investigation is warranted to determine the mechanisms of and to evaluate interventions to decrease tobacco smoke exposure.


Assuntos
Anemia Falciforme/terapia , Hospitalização/tendências , Poluição por Fumaça de Tabaco/análise , Adolescente , Anemia Falciforme/epidemiologia , Criança , Cotinina/análise , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Masculino , Estudos Prospectivos , Análise de Regressão , Estudos Retrospectivos , Saliva/metabolismo , Poluição por Fumaça de Tabaco/efeitos adversos , Poluição por Fumaça de Tabaco/estatística & dados numéricos
19.
J Pediatr Hematol Oncol ; 38(4): 294-300, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26950087

RESUMO

Preventive services can reduce the morbidity of sickle cell disease (SCD) in children but are delivered unreliably. We conducted a retrospective cohort study of children aged 2 to 5 years with SCD, evaluating each child for 14 months and expecting that he/she should receive ≥75% of days covered by antibiotic prophylaxis, ≥1 influenza immunization, and ≥1 transcranial Doppler ultrasound (TCD). We used logistic regression to quantify the relationship between ambulatory generalist and hematologist visits and preventive services delivery. Of 266 children meeting the inclusion criteria, 30% consistently filled prophylactic antibiotic prescriptions. Having ≥2 generalist, non-well child care visits or ≥2 hematologist visits was associated with more reliable antibiotic prophylaxis. Forty-one percent of children received ≥1 influenza immunizations. Children with ≥2 hematologist visits were most likely to be immunized (62% vs. 35% among children without a hematologist visit). Only 25% of children received ≥1 TCD. Children most likely to receive a TCD (42%) were those with ≥2 hematologist visits. One in 20 children received all 3 preventive services. Preventive services delivery to young children with SCD was inconsistent but associated with multiple visits to ambulatory providers. Better connecting children with SCD to hematologists and strengthening preventive care delivery by generalists are both essential.


Assuntos
Anemia Falciforme/terapia , Medicina Preventiva/métodos , Antibioticoprofilaxia/estatística & dados numéricos , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Imunização/estatística & dados numéricos , Influenza Humana/prevenção & controle , Masculino , Visita a Consultório Médico , Estudos Retrospectivos , Ultrassonografia Doppler Transcraniana
20.
South Med J ; 109(9): 495-502, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27598348

RESUMO

Sickle cell disease (SCD) is a heterogeneous inherited disorder of hemoglobin that causes chronic hemolytic anemia, vaso-occlusion, and endothelial dysfunction. These physiologic derangements often lead to multiorgan damage in infancy and throughout childhood. The most common types of SCD are homozygous hemoglobin S (HbSS disease), hemoglobin SC disease, and sickle ß thalassemia. HbSS disease and sickle ß(0) thalassemia often are referred to as sickle cell anemia because they have similar severity. Screening and preventive measures, including infection prophylaxis and vaccination, have significantly improved outcomes for children with SCD. Evidence-based therapies, such as hydroxyurea and transfusion, play an important role in preventing progression of select complications. Many chronic complications develop insidiously and require multidisciplinary care for effective treatment. Primary care physicians, as well as physicians in many other disciplines, may care for these patients and should be familiar with the potential acute and chronic complications of this disease. This review addresses healthcare maintenance guidelines, common complications, and recommendations for management of pediatric patients with SCD.


Assuntos
Anemia Falciforme/terapia , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/uso terapêutico , Criança , Gastroenteropatias/etiologia , Cardiopatias/etiologia , Humanos , Hidroxiureia/uso terapêutico , Pneumopatias/etiologia , Doenças do Sistema Nervoso/etiologia
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