RESUMO
Because of the unique biology of sickle cell disease (SCD) as well as the societal disadvantages and racial inequities suffered by these patients, individuals with SCD have not benefited from the same remarkable advances in care and therapeutics as those with other hematologic disorders. Life expectancy of individuals with SCD is shortened by â¼20 years even with optimal clinical care, and infant mortality continues to be a major concern in low-income countries. As hematologists, we must do more. The American Society of Hematology (ASH) and the ASH Research Collaborative have instituted a multipronged initiative to improve the lives of individuals living with this disease. Here, we describe 2 components of this ASH initiative, the Consortium on Newborn Screening in Africa (CONSA) to improve the early diagnosis of infants in low-resource countries and the SCD Clinical Trial Network to accelerate the development of more effective therapeutics and care for those with this disorder. The combination of SCD-focused initiatives, ASH Research Collaborative, CONSA, and Sickle Cell Clinical Trials Network has enormous potential to dramatically alter the course of SCD worldwide. We believe that the timing is ripe to embark on these critical and worthwhile initiatives and improve the lives of individuals with this disease.
Assuntos
Anemia Falciforme , Doenças Hematológicas , Lactente , Recém-Nascido , Humanos , Anemia Falciforme/terapia , Anemia Falciforme/tratamento farmacológico , Expectativa de Vida , Assistência ao Paciente , Triagem NeonatalRESUMO
Crizanlizumab, a monoclonal antibody against P-selectin, has been shown to reduce vaso-occlusive crises (VOCs) compared to placebo in patients ≥ 16 years with sickle cell disease (SCD). However, there have been rare reports of patients experiencing severe pain and subsequent complications within 24 hours of crizanlizumab infusions. These events are defined as infusion-related reactions (IRRs). Informed by current literature and clinical experience, a group of content experts developed clinical guidelines for the management of IRRs in patients with SCD. We used the RAND/University of California, Los Angeles (UCLA) modified Delphi panel method, a valid, reproducible technique for achieving consensus. We present our recommendations for managing IRRs, which depend on patient characteristics including: prior history of IRRs to other monoclonal antibodies or medications, changes to crizanlizumab infusion rate and patient monitoring, pain severity relative to patient's typical SCD crises, and severe allergic symptoms. These recommendations outline how to evaluate and manage IRRs in patients receiving crizanlizumab. Future research should validate this guidance using clinical data and identify patients at risk for these IRRs.
Assuntos
Anemia Falciforme , Anticorpos Monoclonais Humanizados , Técnica Delphi , Humanos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anemia Falciforme/tratamento farmacológico , Infusões Intravenosas , ConsensoRESUMO
Early mortality in sickle cell disease (SCD) is attributed to increased infections due to loss of splenic function. Marginal zone B cells are important for initial opsonization of pathogens and can be absent in spleen histopathology in SCD. The frequency of unswitched memory B cells (UMBC), the circulating correlate of marginal zone B cells, reflects the immunologic function of the spleen. We hypothesized that asplenia in SCD is associated with alterations in the peripheral blood lymphocyte population and explored whether UMBC deficiency was associated with a clinical phenotype. We analyzed B cell subsets and clinical history for 238 children with SCD and 63 controls. The median proportion of UMBCs was lower in children with SCD compared with controls (4.7% vs. 6.6%, p < .001). Naïve B cells were higher in SCD compared with controls (80.6 vs. 76.3%, respectively, p = .02). UMBC frequency declined by 3.4% per year increase in age in SCD (95% CI: 2%, 4.7%, p < .001), but not in controls. A majority of children in all cohorts had an IgM concentration in the normal range for age and there were no differences between groups (p = .13). Subjects developed titers adequate for long-term protection to fewer serotypes in the polysaccharide vaccine than controls (14.7 vs. 19.4, p < .001). In this cohort, bacteremia was rare and specific clinical complications were not associated with UMBC proportion. In summary, UMBC deficiency occurs in SCD and is associated with age. Future studies should investigate B cell subsets prospectively and identify the mechanism of B cell loss in the spleen.
Assuntos
Anemia Falciforme , Células B de Memória , Vacinas Pneumocócicas , Humanos , Anemia Falciforme/imunologia , Anemia Falciforme/complicações , Vacinas Pneumocócicas/imunologia , Vacinas Pneumocócicas/uso terapêutico , Criança , Masculino , Feminino , Pré-Escolar , Células B de Memória/imunologia , Adolescente , Subpopulações de Linfócitos B/imunologia , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/prevenção & controle , Baço/imunologia , Baço/patologia , Imunoglobulina M/sangueRESUMO
Sickle cell disease (SCD) and systemic lupus erythematosus (SLE) are two uncommon disorders each characterized by multisystemic manifestations. Individuals with SCD exhibit abnormalities in the complement pathway, which may predispose patients to develop autoimmune disorders such as SLE. As many manifestations of SLE mimic those of SCD, diagnosis and therapeutic management of SLE in a patient with known SCD may be delayed. In this study, we describe our institutional experience of diagnosing and managing concomitant SCD and SLE. We offer insights into the complex interplay between these conditions to enhance early recognition and effective management of concurrent SCD and SLE.
Assuntos
Anemia Falciforme , Lúpus Eritematoso Sistêmico , Adolescente , Feminino , Humanos , Adulto Jovem , Anemia Falciforme/complicações , Lúpus Eritematoso Sistêmico/complicaçõesRESUMO
PURPOSE OF REVIEW: Low-income and middle-income countries (LMICs), primarily in sub-Saharan Africa (SSA), predominantly experience the burden of sickle cell disease (SCD). High frequency of acute and chronic complications leads to increased utilization of healthcare, which burdens fragile health systems. Mortality for children with limited healthcare access remains alarmingly high. Cellular based therapies such as allogeneic hematopoietic stem cell transplant (HSCT) are increasingly used in resource-rich settings as curative therapy for SCD. Broad access to curative therapies for SCD in SSA would dramatically alter the global impact of the disease. RECENT FINDINGS: Currently, application of cellular based therapies in LMICs is limited by cost, personnel, and availability of HSCT-specific technologies and supportive care. Despite the challenges, HSCT for SCD is moving forward in LMICs. Highly anticipated gene modification therapies have recently proven well tolerated and feasible in clinical trials in resource-rich countries, but access remains extremely limited. SUMMARY: Translation of curative cellular based therapies for SCD should be prioritized to LMICs where the disease burden and cost of noncurative treatments is high, and long-term quality of life is poor. Focus on thoughtful modifications of current and future therapies to meet the need in LMICs, especially in SSA, will be especially impactful.
Assuntos
Anemia Falciforme , Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , África Subsaariana/epidemiologia , Anemia Falciforme/complicações , Anemia Falciforme/terapia , Criança , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Qualidade de VidaRESUMO
Pain management is challenging for patients with sickle cell disease (SCD) who present in vaso-occlusive crisis (VOC). Opioid therapy is highly effective, nevertheless undesirable side effects can hinder their effectiveness. Regional anesthesia with deposition of perineural anesthetic offers nociceptive blockade, local vasodilatation, and reduces the inflammatory response. Among pediatric patients, continuous peripheral nerve block (CPNB) for perioperative adjunctive analgesia is safe. Herein, we describe the trajectory of a cohort of pediatric SCD patients with opioid-refractory upper-extremity VOC following placement of CPNBs for analgesia; highlighting reduced opioid consumption, improved pain scores, and decreased length of hospitalization.
Assuntos
Anemia Falciforme , Anestesia por Condução , Analgésicos Opioides/uso terapêutico , Anemia Falciforme/complicações , Anemia Falciforme/terapia , Criança , Humanos , Dor/tratamento farmacológico , Dor/etiologiaRESUMO
Sickle cell disease (SCD) is a group of common, life-threatening disorders caused by a point mutation in the ß globin gene. Early diagnosis through newborn and early childhood screening, parental education, and preventive treatments are known to reduce mortality. However, the cost and complexity of conventional diagnostic methods limit the feasibility of early diagnosis for SCD in resource-limited areas worldwide. Although several point-of-care tests are commercially available, most are antibody-based tests, which cannot be used in patients who have recently received a blood transfusion. Here, we describe the development of a rapid, low-cost nucleic acid test that uses real-time fluorescence to detect the point mutation encoding hemoglobin S (HbS) in one round of isothermal recombinase polymerase amplification (RPA). When tested with a set of clinical samples from SCD patients and healthy volunteers, our assay demonstrated 100% sensitivity for both the ßA globin and ßS globin alleles and 94.7 and 97.1% specificities for the ßA globin allele and ßS globin allele, respectively (n = 91). Finally, we demonstrate proof-of-concept sample-to-answer genotyping of genomic DNA from capillary blood using an alkaline lysis procedure and direct input of diluted lysate into RPA. The workflow is performed in <30 min at a cost of <$5 USD on a commercially available benchtop fluorimeter and an open-source miniature fluorimeter. This study demonstrates the potential utility of a rapid, sample-to-answer nucleic acid test for SCD that may be implemented near the point of care and could be adapted to other disease-causing point mutations in genomic DNA.
Assuntos
Anemia Falciforme , Recombinases , Alelos , Anemia Falciforme/diagnóstico , Anemia Falciforme/genética , Pré-Escolar , Hemoglobina Falciforme/análise , Humanos , Recém-Nascido , Técnicas de Amplificação de Ácido Nucleico , Sistemas Automatizados de Assistência Junto ao Leito , Sensibilidade e EspecificidadeRESUMO
This study compared outcomes following total (TS) or partial splenectomy (PS) among patients with hereditary spherocytosis. Seventy-nine patients (TS = 33, PS = 46) were identified. The follow-up period was longer after PS (59.6 vs. 24.9 months, p < .001). Long-term adverse events occurred more frequently following PS (50% vs. 29%, p = .001). Anemia, jaundice, and fatigue recurred in six patients with PS, leading to five completion splenectomies. Hemoglobin was not different between PS and TS by 5 years post-procedure (12.3 vs. 13.4 g/dL, p = .25). Both PS and TS ameliorate symptoms and improve hematologic parameters. The rate of secondary surgery following PS should be considered when planning the initial surgical procedure.
Assuntos
Laboratórios/normas , Esferocitose Hereditária/cirurgia , Esplenectomia/métodos , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos , Esferocitose Hereditária/patologia , Resultado do TratamentoRESUMO
Sickle cell disease (SCD) is a group of recessively inherited disorders of erythrocyte function that presents an ongoing threat to reducing childhood and adult morbidity and mortality around the world. While decades of research have led to improved survival for SCD patients in wealthy countries, survival remains dismal in low- and middle-income countries. Much of the early mortality associated with SCD is attributed to increased risk of infections due to early loss of splenic function. In the West, bacterial infections with encapsulated organisms are a primary concern. In sub-Saharan Africa, where the majority of infants with SCD are born, the same is true. However malaria presents an additional threat to survival. The search for factors that define variability in sickle cell phenotypes should include environmental modifiers, such as malaria. Further exploration of this relationship could lead to novel strategies to reduce morbidity and mortality attributable to infections. In this review, we explore the interactions between SCD, malaria and the spleen to better understand how splenomegaly and splenic (dys)function may co-exist in patients with SCD living in malaria-endemic areas.
Assuntos
Anemia Falciforme/complicações , Malária/complicações , Esplenomegalia/etiologia , África/epidemiologia , Anemia Falciforme/epidemiologia , Anemia Falciforme/patologia , Doenças Endêmicas , Saúde Global , Humanos , Malária/epidemiologia , Baço/patologia , Baço/fisiopatologia , Esplenomegalia/epidemiologiaRESUMO
Senicapoc, a Gardos channel inhibitor, prevented erythrocyte dehydration in clinical trials of patients with sickle cell disease. We tested the hypothesis that senicapoc-induced blockade of the Gardos channel inhibits Plasmodium growth. Senicapoc inhibited in vitro growth of human and primate plasmodia during the clinical blood stage. Senicapoc treatment suppressed P. yoelii parasitemia in vivo in C57BL/6 mice. The reassuring safety and biochemical profile of senicapoc encourage its use in antimalarial development.
Assuntos
Acetamidas/farmacologia , Antimaláricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Plasmodium knowlesi/efeitos dos fármacos , Plasmodium yoelii/efeitos dos fármacos , Compostos de Tritil/farmacologia , Trofozoítos/efeitos dos fármacos , Animais , Transporte Biológico/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Interações Hospedeiro-Parasita , Humanos , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/antagonistas & inibidores , Canais de Potássio Ativados por Cálcio de Condutância Intermediária/metabolismo , Macaca mulatta , Camundongos , Camundongos Endogâmicos C57BL , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/metabolismo , Plasmodium knowlesi/crescimento & desenvolvimento , Plasmodium knowlesi/metabolismo , Plasmodium yoelii/crescimento & desenvolvimento , Plasmodium yoelii/metabolismo , Trofozoítos/crescimento & desenvolvimento , Trofozoítos/metabolismo , Água/metabolismoRESUMO
Patients with GATA2 haploinsufficiency have a significant predisposition to developing cytopenias, unique infectious manifestations, and myelodysplastic syndrome/acute myeloid leukemia (MDS/AML). We report a unique case of a patient who presented with B-cell acute lymphoblastic leukemia (B-ALL) and was subsequently diagnosed with monocytopenia and mycobacterium avium complex (MonoMAC) syndrome/GATA2 haploinsufficiency. The development of MDS/AML in patients with GATA2 haploinsufficiency is well described, however, the development of ALL has not been reported in the literature. ALL may be associated with GATA2 haploinsufficiency. Clinicians should be attuned to the features of the MonoMAC syndrome in patients with ALL that would prompt additional testing and alter treatment.
Assuntos
Fator de Transcrição GATA2/genética , Haploinsuficiência/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Criança , Feminino , HumanosRESUMO
BACKGROUND: Fever and neutropenia (F&N) is a pediatric oncology emergency due to the risk of disseminated infection. Quality improvement (QI) efforts to improve time to antibiotics for F&N in the emergency department have been documented, but the issue has not been studied in the established inpatient setting. PROCEDURE: We undertook a prospective cohort QI study to decrease time to antibiotics for neutropenic pediatric oncology inpatients with new fever to <60 min. Our key intervention was discussion of a plan in case of new fever, including antibiotic(s) to be started, for each patient on rounds. Timing for each step in the process, from fever identification to antibiotic administration, was measured through the electronic medical record for each fever event. RESULTS: The median time to antibiotics during the 3-three month intervention study period was 76.0 min, although the distribution was skewed due to several long outliers (mean 142.5, interquartile range 51-206, range 47-593 min). Time to antibiotics was significantly shorter when a fever contingency plan was documented in the most recent note than not (mean 102 vs. 254 min, P = 0.039). Over the total 2.75 year data-collection period, the quarterly percentage of patients receiving antibiotics within 60 min has improved from 35 to 65, whereas quarterly mean time to antibiotics has improved from 99 to 50 min. CONCLUSIONS: Daily discussion of a fever contingency plan appears effective in decreasing the time to antibiotics for neutropenic pediatric oncology inpatients with new fever, likely by circumventing the need for multi-level discussion of the antibiotic plan when fever is identified.
Assuntos
Antibacterianos/administração & dosagem , Febre/tratamento farmacológico , Neoplasias/complicações , Neutropenia/complicações , Melhoria de Qualidade , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Registros Eletrônicos de Saúde , Febre/etiologia , Humanos , Lactente , Recém-Nascido , Neutropenia/tratamento farmacológico , Estudos Prospectivos , Fatores de TempoRESUMO
BACKGROUND: In malaria-endemic countries in West Africa, sickle cell disease (SCD) contributes to childhood mortality. Historically, Liberia had regions wherein hemoglobin S and beta-thalassemia trait were mutually exclusive. Data on hemoglobinopathies in the Monrovia, the capital, are outdated and do not reflect urban migration. Updating the epidemiology of SCD is necessary to plan a public health and clinical agenda. Neither newborn screening (NBS) nor screening tools were available in country. This pilot study aimed to determine the feasibility of NBS using a South-South partnership and define the incidence of sickle cell trait (SCT) and SCD in Monrovia. PROCEDURE: This descriptive epidemiologic feasibility study collected dried blood spots from 2,785 consecutive newborns delivered at a hospital in Monrovia. Samples were analyzed by isoelectric focusing at a regional reference laboratory. Infants with SCD were referred for preventive care. RESULTS: SCT occurred in 10.31% of infants screened. SCD occurred in 33 infants screened [1.19% (95% confidence interval [CI]: 0.79-1.59%)] (FS: 28/33, FSB: 2/33, FSA: 2/33, FSX: 1/33). There were no infants with FSC phenotype observed. Nonsickling hemoglobin phenotypes "FC" and "F" were each present in three infants screened. Seventy-six percent of infants with SCD were brought to care, demonstrating the feasibility of our approach. CONCLUSIONS: The incidence of SCD and other hemoglobinopathies remains high in Liberia. Additional studies are needed to clarify sickle genotypes and identify the contribution of silent beta-thalassemia alleles. By developing regional partnerships, countries similar to Liberia can acquire current data to inform NBS as an important public health initiative toward improving child health.
Assuntos
Anemia Falciforme/diagnóstico , Anemia Falciforme/epidemiologia , Triagem Neonatal , Feminino , Humanos , Incidência , Recém-Nascido , Focalização Isoelétrica , Libéria/epidemiologia , Masculino , Projetos PilotoAssuntos
Anemia Falciforme , Cuidadores , África , Criança , Feminino , Humanos , Mães , Medição de RiscoRESUMO
Chronic transfusion therapy has played a central role in extending life expectancy for patients with hemoglobinopathies such as thalassemia. However, this life-saving therapy is associated with numerous complications that now comprise the bulk of management considerations for patients with thalassemia. This review reports on the experience of the Thalassemia Longitudinal Cohort and reviews available literature to establish guidelines for the management of patients with thalassemia.
Assuntos
Hemoglobinopatias/terapia , Monitorização Fisiológica/normas , Talassemia/terapia , Transfusão de Sangue , Humanos , Estudos LongitudinaisRESUMO
A 4-month-old full-term female presented with growth faltering associated with progressive feeding difficulty, rash, abdominal distension, and developmental delays. She was found to have disconjugate gaze, abnormal visual tracking, mixed tone, bruising, and splenomegaly on examination. Initial workup was notable for thrombocytopenia and positive cytomegalovirus (CMV) immunoglobulin G and immunoglobulin M antibodies. She initially presented to the infectious diseases CMV clinic, where she was noted to have severe malnutrition, prompting referral to the emergency department for hospital admission to optimize nutrition with nasogastric tube feeding and facilitate additional evaluation. An active CMV infection with viruria and viremia was confirmed, but elements of her presentation and workup including brain magnetic resonance imaging were not consistent with isolated CMV infection. To avoid premature diagnostic closure, a multidisciplinary workup was initiated and ultimately established her diagnosis.
Assuntos
Esplenomegalia , Trombocitopenia , Humanos , Feminino , Lactente , Esplenomegalia/etiologia , Esplenomegalia/diagnóstico por imagem , Trombocitopenia/diagnóstico , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/diagnóstico , Insuficiência de Crescimento/etiologia , Diagnóstico DiferencialRESUMO
CONTEXT: Pain attributable to sickle cell disease (SCD) is often unpredictable, recurrent, and requires complex treatments. Subanesthetic ketamine infusion has been studied in other diseases and disorders, but there is still limited data on its efficacy in pain management for SCD. OBJECTIVES: The primary objective is to determine if subanesthetic ketamine infusion reduces pain scores and opioid requirements in hospitalized pediatric patients with SCD. RESULTS: Forty-six admissions among 22 patients between February 2018 and December 2019 were analyzed. We observed decrease in pain scores within 24 hours of ketamine initiation in 34 of 46 admissions (mean pain score per patient before ketamine initiation: 2.2-9.7, mean pain score per patient after ketamine initiation: 0-9.7; P < .05). We observed a decrease in pain scores in the remaining 12 admissions after greater than 24 hours of ketamine initiation. Opioid usage declined after ketamine infusion, with a difference of means in oral morphine equivalents before and after ketamine of 122.8 mg/day. The side effects observed with ketamine infusion included hallucinations in 11 (23.9%) admissions. Only four (8.7%) admissions required cessation of the infusion due to side effects. The readmission rate at two weeks and four weeks after first ketamine infusion was the same (12.5%) at both time points. For all patients in the cohort, the introduction of ketamine into pain regimens did not reduce the number of admissions in the year following ketamine initiation relative to the year prior. CONCLUSION: In pediatric patients with SCD, subanesthetic ketamine was safe as a continuous infusion and effectively reduced both pain scores and opioid requirements.
Assuntos
Anemia Falciforme , Ketamina , Humanos , Criança , Ketamina/uso terapêutico , Ketamina/efeitos adversos , Analgésicos Opioides/uso terapêutico , Dor/tratamento farmacológico , Dor/etiologia , Morfina , Anemia Falciforme/complicações , Anemia Falciforme/tratamento farmacológico , AnalgésicosRESUMO
Isothermal nucleic acid amplification tests have the potential to improve disease diagnosis at the point of care, but it remains challenging to develop multiplexed tests that can detect ≥3 targets or to detect point mutations that may cause disease. These capabilities are critical to enabling informed clinical decision-making for many applications, such as sickle cell disease (SCD). To address this, we describe the development of a multiplexed allele-specific recombinase polymerase amplification (RPA) assay with lateral flow readout. We first characterize the specificity of RPA using primer design strategies employed in PCR to achieve point mutation detection, and demonstrate the utility of these strategies in achieving selective isothermal amplification and detection of genomic DNA encoding for the healthy ßA globin allele, or genomic DNA containing point mutations encoding for pathologic ßS and ßC globin alleles, which are responsible for most sickle cell disorders. We then optimize reaction conditions to achieve multiplexed amplification and identification of the three alleles in a single reaction. Finally, we perform a small pilot study with 20 extracted genomic DNA samples from SCD patients and healthy volunteers - of the 13 samples with valid results, the assay demonstrated 100% sensitivity and 100% specificity for detecting pathologic alleles, and an overall accuracy of 92.3% for genotype prediction. This multiplexed assay is rapid, minimally instrumented, and when combined with point-of-care sample preparation, could enable DNA-based diagnosis of SCD in low-resource settings. The strategies reported here could be applied to other challenges, such as detection of mutations that confer drug resistance.
Assuntos
Alelos , Anemia Falciforme , Técnicas de Amplificação de Ácido Nucleico , Recombinases , Anemia Falciforme/genética , Anemia Falciforme/diagnóstico , Humanos , Recombinases/metabolismo , Globinas beta/genética , Mutação PuntualRESUMO
OBJECTIVE: Voxelotor, a FDA-approved drug for the treatment of patients with sickle cell disease (SCD), inhibits hemoglobin S (HbS) polymerization and increases total hemoglobin via hemolysis reduction. This drug has shown unique patterns in hemoglobin fractionation, affecting its interpretation. We aimed to evaluate whether these voxelotor-induced changes can be linked to improvement of hemolysis markers in pediatric patients on voxelotor. METHODS: A total of 15 patients (age 12 to 20 years; 40% females) on voxelotor were evaluated to compare changes in the hemoglobin fractionation by capillary electrophoresis, total hemoglobin, reticulocyte percentage (retic%), lactate dehydrogenase (LDH), and bilirubin measurements before and after the recorded date of voxelotor prescription. RESULTS: Hemoglobin fractionation showed changes in the profile of 60% (9/15) of the patients studied. Out of the 9 patients for which voxelotor showed changes in the hemoglobin fractionation, 44% (4/9) had an increase of >1 g/dL in their total hemoglobin after voxelotor treatment was started. Assessment of other hemolysis markers available showed decreased LDH (4/4), retic % (6/8), and bilirubin (3/4). CONCLUSIONS: Unique pattern of hemoglobin fractionation analysis following therapy with voxelotor has potential as a tool for the assessment of response and/or compliance to voxelotor for the treatment of SCD.