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Background: Exagamglogene autotemcel (exa-cel) is a nonviral cell therapy designed to reactivate fetal hemoglobin synthesis by means of ex vivo clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 gene editing of autologous CD34+ hematopoietic stem and progenitor cells (HSPCs) at the erythroid-specific enhancer region of BCL11A ., Methods: We conducted a phase 3, single-group, open-label study of exa-cel in patients 12 to 35 years of age with sickle cell disease who had had at least two severe vaso-occlusive crises in each of the 2 years before screening. CD34+ HSPCs were edited with the use of CRISPR-Cas9. Before the exa-cel infusion, patients underwent myeloablative conditioning with pharmacokinetically dose-adjusted busulfan. The primary end point was freedom from severe vaso-occlusive crises for at least 12 consecutive months. A key secondary end point was freedom from inpatient hospitalization for severe vaso-occlusive crises for at least 12 consecutive months. The safety of exa-cel was also assessed., Results: A total of 44 patients received exa-cel, and the median follow-up was 19.3 months (range, 0.8 to 48.1). Neutrophils and platelets engrafted in each patient. Of the 30 patients who had sufficient follow-up to be evaluated, 29 (97%; 95% confidence interval [CI], 83 to 100) were free from vaso-occlusive crises for at least 12 consecutive months, and all 30 (100%; 95% CI, 88 to 100) were free from hospitalizations for vaso-occlusive crises for at least 12 consecutive months (P<0.001 for both comparisons against the null hypothesis of a 50% response). The safety profile of exa-cel was generally consistent with that of myeloablative busulfan conditioning and autologous HSPC transplantation. No cancers occurred., Conclusions: Treatment with exa-cel eliminated vaso-occlusive crises in 97% of patients with sickle cell disease for a period of 12 months or more. (CLIMB SCD-121; ClinicalTrials.gov number, NCT03745287.)., (Copyright © 2024 Massachusetts Medical Society.)

The acute pain crisis (APC) is the commonest complication of sickle cell disease (SCD). Severe episodes may require treatment in hospital with strong opioid analgesic drugs, combined with additional supportive care measures. Guidelines for APC management have been produced over the past two decades gathering evidence from published studies, expert opinion, and patient perspective. Unfortunately, reports from multiple sources indicate that guidelines are often not followed, and that acute care in emergency departments and on acute medical wards is suboptimal. It is important to understand what leads to this breakdown in health care, and to identify evidence-based interventions which could be implemented to improve care. This review focuses on recently published articles as well as information about on-going clinical trials. Aspects of care which could potentially make a difference to patient experience include availability and accessibility of individual care plans agreed between patient and treating specialist, innovative means of delivering initial opioids to reduce time to first analgesia, and availability of a specialist unit away from the ED, where expert care can be delivered in a more compassionate environment. The current evidence of improved outcomes and health economic advantage with these interventions is inadequate, and this is hampering their implementation into health care systems., Competing Interests: Declaration of competing interest PT: Advisory boards and committees: Pfizer, Vertex, Novo Nordisk, Agios. Research funding: Vertex PLC. KA: Advisory boards and honoraria: Pfizer, Vertex, Novartis. SK: No conflicts of interest. LA: No conflicts of interest. SH: No conflicts of interest. CB: No conflicts of interest. S S-S: No conflicts of interest. SL: Consultancy and honoraria: Sanius health, Kite Gilead, Vertex, GBT/Pfizer., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Gene modification of haematopoietic stem cells (HSCs) is a potentially curative approach to sickle cell disease (SCD) and offers hope for patients who are not eligible for allogeneic HSC transplantation. Current approaches require in vitro manipulation of healthy autologous HSC prior to their transplantation. However, the health and integrity of HSCs may be compromised by a variety of disease processes in SCD, and challenges have emerged in the clinical trials of gene therapy. There is also concern about increased susceptibility to haematological malignancies during long-term follow up of patients, and this raises questions about genomic stability in the stem cell compartment. In this review, we evaluate the evidence for HSC deficits in SCD and then discuss their potential causation. Finally, we suggest several questions which need to be addressed in order to progress with successful HSC manipulation for gene therapy in SCD., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interests., (Copyright © 2023. Published by Elsevier Ltd.)

Sickle cell disease is one of the most common, life-threatening, non-communicable diseases in the world and a major public health problem. Following the implementation of simple preventive and therapeutic modalities, infant mortality has almost been abolished in high-income countries, but only a small amount of progress has been made in improving survival in adulthood. Progressive end-organ damage, partly related to a systemic vasculopathy, is increasingly recognised. With the availability of a variety of novel disease-modifying drugs, gene addition and gene editing strategies, matched sibling donor haematopoietic stem cell transplantation (HSCT) in children (offering an overall survival rate of 95% and an event-free survival rate of 92%), and encouraging outcomes after alternative donor HSCT, the new challenge is to risk stratify patients, revise transplantation indications, and define the best therapeutic approach for each patient. The ultimate challenge will be to enable these advances in low-income and middle-income countries, where disease prevalence is highest and where innovative strategies are most needed., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Central nervous system (CNS) complications are among the most common, devastating sequelae of sickle cell disease (SCD) occurring throughout the lifespan., Objective: These evidence-based guidelines of the American Society of Hematology are intended to support the SCD community in decisions about prevention, diagnosis, and treatment of the most common neurological morbidities in SCD., Methods: The Mayo Evidence-Based Practice Research Program supported the guideline development process, including updating or performing systematic evidence reviews. The panel used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, including GRADE evidence-to-decision frameworks, to assess evidence and make recommendations., Results: The panel placed a higher value on maintaining cognitive function than on being alive with significantly less than baseline cognitive function. The panel developed 19 recommendations with evidence-based strategies to prevent, diagnose, and treat CNS complications of SCD in low-middle- and high-income settings., Conclusions: Three of 19 recommendations immediately impact clinical care. These recommendations include: use of transcranial Doppler ultrasound screening and hydroxyurea for primary stroke prevention in children with hemoglobin SS (HbSS) and hemoglobin Sβ0 (HbSβ0) thalassemia living in low-middle-income settings; surveillance for developmental delay, cognitive impairments, and neurodevelopmental disorders in children; and use of magnetic resonance imaging of the brain without sedation to detect silent cerebral infarcts at least once in early-school-age children and once in adults with HbSS or HbSβ0 thalassemia. Individuals with SCD, their family members, and clinicians should become aware of and implement these recommendations to reduce the burden of CNS complications in children and adults with SCD., (© 2020 by The American Society of Hematology.)

Background: Pregnancies in women with sickle cell disease (SCD) are associated with a higher risk of sickle and pregnancy complications. Limited options exist for treating SCD during pregnancy. Serial prophylactic exchange blood transfusion (SPEBT) has been shown to be effective in treating SCD outside pregnancy, but evidence is lacking regarding its use during pregnancy. The aim of this study is to assess the feasibility and acceptability of conducting a future phase 3 randomised controlled trial (RCT) to establish the clinical and cost effectiveness of SPEBT in pregnant women with SCD., Methods: The study is an individually randomised, two-arm, feasibility trial with embedded qualitative and health economic studies. Fifty women, 18 years of age and older, with SCD and a singleton pregnancy at ≤ 18 weeks' gestation will be recruited from six hospitals in England. Randomisation will be conducted using a secure online database and minimised by centre, SCD genotype and maternal age. Women allocated to the intervention arm will receive SPEBT commencing at ≤ 18 weeks' gestation, performed using automated erythrocytapheresis every 6-10 weeks until the end of pregnancy, aiming to maintain HbS% or combined HbS/HbC% below 30%. Women in the standard care arm will only receive transfusion when clinically indicated. The primary outcome will be the recruitment rate. Additional endpoints include reasons for refusal to participate, attrition rate, protocol adherence, and maternal and neonatal outcomes. Women will be monitored throughout pregnancy to assess maternal, sickle, and foetal complications. Detailed information about adverse events (including hospital admission) and birth outcomes will be extracted from medical records and via interview at 6 weeks postpartum. An embedded qualitative study will consist of interviews with (a) 15-25 trial participants to assess experiences and acceptability, (b) 5-15 women who decline to participate to identify barriers to recruitment and (c) 15-20 clinical staff to explore fidelity and acceptability. A health economic study will inform a future cost effectiveness and cost-utility analysis., Discussion: This feasibility study aims to rigorously evaluate SPEBT as a treatment for SCD in pregnancy and its impact on maternal and infant outcomes., Trial Registration: NIH registry (www.clinicaltrials.gov), registration number NCT03975894 (registered 05/06/19); ISRCTN (www.isrctn.com), registration number ISRCTN52684446 (retrospectively registered 02/08/19).

Background: Young people's experiences of healthcare as they move into adult services can have a major impact on their health, and the transition period for young people with sickle cell disease (SCD) needs improvement. In this study, we explore how young people with SCD experience healthcare during this period of transition., Methods: We conducted a co-produced longitudinal qualitative study, including 80 interviews in 2016-2017 with young people with SCD aged 13-21 (mean age 16.6) across two cities in England. We recruited 48 participants (30 female, 18 male): 27 interviews were one-off, and 53 were repeated 2-3 times over approximately 18 months. We used an inductive analytical approach, combining elements of Grounded Theory and thematic analysis., Results: Participants reported significant problems with the care they received in A&E during painful episodes, and in hospital wards as inpatients during unplanned healthcare. They experienced delays in being given pain relief and their basic care needs were not always met. Participants said that non-specialist healthcare staff did not seem to know enough about SCD and when they tried to work with staff to improve care, staff often seemed not prepared to listen to them or act on what they said. Participants said they felt out of place in adult wards and uncomfortable with the differences in adult compared with paediatric wards. Because of their experiences, they tried to avoid being admitted to hospital, attempting to manage their painful episodes at home and accessing unplanned hospital care only as a last resort. By contrast, they did not report having problems within SCD specialist services during planned, routine care., Conclusions: Our study underscores the need for improvements to make services youth-friendly and youth-responsive, including training staff in SCD-specific care, compassionate care and communication skills that will help them elicit and act on young people's voices to ensure they are involved in shaping their own healthcare. If young people are prevented from using transition skills (self-management, self-advocacy), or treated by staff who they worry do not have enough medical competency in their condition, they may well lose their trust in services, potentially compromising their own health.

A brief measure of patient satisfaction with treatment for pain is needed to help improve the treatment of painful episodes caused by sickle cell disease (SCD), especially during and after the transition from paediatric to adult care. Focus groups of 28 adolescent and adult patients were consulted about the content, clarity and relevance of 30 potential items, resulting in an 18-item version. This was validated by analysing questionnaire responses from 120 patients aged 12-53 years. Confirmatory factor analysis and item analysis indicated five subscales with high internal reliability: 'Communication and Involvement' (6 items, α = 0·87); 'Respect and Dignity' (3 items, α = 0·82); 'Pain Control' (3 items, α = 0·91); 'Staff Attitudes and Behaviour' (4 items, α = 0·88); and 'Overall Satisfaction' (2 items, α = 0·85) plus a Total Satisfaction score (18 items, α = 0·96). High negative correlations with the Picker Patient Experience Questionnaire, a measure of problem experiences, indicated good convergent validity. Lower satisfaction scores among patients aged over 18 years, those admitted via the emergency department, those treated by non-specialist hospital staff, and those reporting more breakthrough pain indicated good concurrent validity. The questionnaire provides a convenient brief measure that can be used to inform and evaluate improvements in healthcare for adolescent and adult patients with SCD, and could potentially be adapted for other painful conditions., (© 2019 British Society for Haematology and John Wiley & Sons Ltd.)

Background: Deoxygenated sickle hemoglobin (HbS) polymerization drives the pathophysiology of sickle cell disease. Therefore, direct inhibition of HbS polymerization has potential to favorably modify disease outcomes. Voxelotor is an HbS polymerization inhibitor., Methods: In a multicenter, phase 3, double-blind, randomized, placebo-controlled trial, we compared the efficacy and safety of two dose levels of voxelotor (1500 mg and 900 mg, administered orally once daily) with placebo in persons with sickle cell disease. The primary end point was the percentage of participants who had a hemoglobin response, which was defined as an increase of more than 1.0 g per deciliter from baseline at week 24 in the intention-to-treat analysis., Results: A total of 274 participants were randomly assigned in a 1:1:1 ratio to receive a once-daily oral dose of 1500 mg of voxelotor, 900 mg of voxelotor, or placebo. Most participants had sickle cell anemia (homozygous hemoglobin S or hemoglobin Sβ 0 -thalassemia), and approximately two thirds were receiving hydroxyurea at baseline. In the intention-to-treat analysis, a significantly higher percentage of participants had a hemoglobin response in the 1500-mg voxelotor group (51%; 95% confidence interval [CI], 41 to 61) than in the placebo group (7%; 95% CI, 1 to 12). Anemia worsened between baseline and week 24 in fewer participants in each voxelotor dose group than in those receiving placebo. At week 24, the 1500-mg voxelotor group had significantly greater reductions from baseline in the indirect bilirubin level and percentage of reticulocytes than the placebo group. The percentage of participants with an adverse event that occurred or worsened during the treatment period was similar across the trial groups. Adverse events of at least grade 3 occurred in 26% of the participants in the 1500-mg voxelotor group, 23% in the 900-mg voxelotor group, and 26% in the placebo group. Most adverse events were not related to the trial drug or placebo, as determined by the investigators., Conclusions: In this phase 3 randomized, placebo-controlled trial involving participants with sickle cell disease, voxelotor significantly increased hemoglobin levels and reduced markers of hemolysis. These findings are consistent with inhibition of HbS polymerization and indicate a disease-modifying potential. (Funded by Global Blood Therapeutics; HOPE ClinicalTrials.gov number, NCT03036813.)., (Copyright © 2019 Massachusetts Medical Society.)

Background: The Adult Sickle Cell Quality of Life Measurement Information System (ASCQ-Me) has been shown to be a reliable and valid questionnaire measuring health-related quality of life (HRQoL) in the US sickle cell disease (SCD) population. The study objective was to test the validity and reliability of the ASCQ-Me for use in the UK., Methods: The US ASCQ-Me, Hospital Anxiety and Depression Scale (HADS), self-reported symptoms, and Medical Outcome Survey Short Form 36 (SF-36) were administered to 173 patients with SCD. Clinical severity was assessed by the number of painful episodes indicated by hospital admissions., Results: The results showed that the item banks of the UK ASCQ-Me had good internal consistency. Anxiety and depression were strongly correlated with the emotional, and social item banks of the UK ASCQ-Me, with moderate correlations between the UK ASCQ-Me item banks and SF-36 components suggesting convergent validity. A confirmatory factor analysis confirmed the conceptual framework of the scale as being the same as the US ASCQ-Me, indicating construct validity. Known groups validity was found, with the ASCQ-Me being able to differentiate by SCD severity groups., Conclusion: The analysis of the sample shows evidence of both validity and reliability of the ASCQ-Me for use in the UK SCD population.

New treatments directly targeting polymerization of sickle hemoglobin (HbS), the proximate event in the pathophysiology of sickle cell disease (SCD), are needed to address the severe morbidity and early mortality associated with the disease. Voxelotor (GBT440) is a first-in-class oral therapy specifically developed to treat SCD by modulating the affinity of hemoglobin (Hb) for oxygen, thus inhibiting HbS polymerization and downstream adverse effects of hemolytic anemia and vaso-occlusion. GBT440-001 was a phase 1/2 randomized, double-blind, placebo-controlled, single and multiple ascending dose study of voxelotor in adult healthy volunteers and patients with SCD, followed by a single-arm, open-label extension study. This report describes results of voxelotor (500-1000 mg per day) in patients with sickle cell anemia. The study evaluated the safety, tolerability, pharmacokinetic, and pharmacodynamic properties of voxelotor and established proof of concept by improving clinical measures of anemia, hemolysis, and sickling. Thirty-eight patients with SCD received 28 days of voxelotor 500, 700, or 1000 mg per day or placebo; 16 patients received 90 days of voxelotor 700 or 900 mg per day or placebo. Four patients from the 90-day cohort were subsequently enrolled in an extension study and treated with voxelotor 900 mg per day for 6 months. All patients who received multiple doses of voxelotor for ≥28 days experienced hematologic improvements including increased Hb and reduction in hemolysis and percentage of sickled red cells, supporting the potential of voxelotor to serve as a disease-modifying therapy for SCD. Voxelotor was well tolerated with no treatment-related serious adverse events and no evidence of tissue hypoxia. These trials were registered at www.clinicaltrials.gov as #NCT02285088 and #NCT03041909., (© 2019 by The American Society of Hematology.)

Executive deficits are commonly reported in children with sickle cell anemia. Earlier identification of executive deficits would give more scope for intervention, but this cognitive domain has not been routinely investigated due to a lack of age-appropriate tasks normed for preschool children. In particular, information relating to patient performance on an executive task that reflects an everyday activity in the classroom could provide important insight and practical recommendations for the classroom teacher at this key developmental juncture as they enter the academic domain. The performance of 22 children with sickle cell anemia was compared to 24 matched control children on the Preschool Executive Task Assessment. Findings reveal that children with sickle cell anemia are performing poorer than their matched peers on this multi-step assessment. In particular, children with sickle cell anemia required more structured support to shift focus after a completed step, as reflected by poorer scores in the quantitative Sequencing and Completion domains. They also required more support to stay on task, as seen by poorer ratings in the qualitative Distractibility domain. Abbreviations :PETA: Preschool Executive Task Assessment; SCA: Sickle Cell Anemia; EF: Executive Functioning.

Sickle Cell Disease (SCD) is an increasing global health problem and presents significant challenges to European health care systems. Newborn screening (NBS) for SCD enables early initiation of preventive measures and has contributed to a reduction in childhood mortality from SCD. Policies and methodologies for NBS vary in different countries, and this might have consequences for the quality of care and clinical outcomes for SCD across Europe. A two-day Pan-European consensus conference was held in Berlin in April 2017 in order to appraise the current status of NBS for SCD and to develop consensus-based statements on indications and methodology for NBS for SCD in Europe. More than 50 SCD experts from 13 European countries participated in the conference. This paper aims to summarise the discussions and present consensus recommendations which can be used to support the development of NBS programmes in European countries where they do not yet exist, and to review existing programmes., (© 2018 British Society for Haematology and John Wiley & Sons Ltd.)

The pathophysiology, clinical presentation, and natural history of acute pain in sickle cell disease are unique and require a disease-centered approach that also applies general principles of acute and chronic pain management. The majority of acute pain episodes are managed at home without the need to access health care. The long-term consequences of poorly treated acute pain include chronic pain, adverse effects of chronic opioid usage, psychological maladjustment, poor quality of life, and excessive health care utilization. There is no standard protocol for management of an acute pain crisis in either the hospital or the community. The assumptions that severe acute pain must be managed in the hospital with parenteral opioids and that strong opioids are needed for home management of pain need to be questioned. Pain management in the emergency department often does not meet acceptable standards, while chronic use of strong opioids is likely to result in opioid-induced hyperalgesia, exacerbation of chronic pain symptoms, and opioid dependency. We suggest that an integrated approach is needed to control the underlying condition, modify psychological responses, optimize social support, and ensure that health care services provide safe, effective, and prompt treatment of acute pain and appropriate management of chronic pain. This integrated approach should begin at an early age and continue through the adolescent, transition, and adult phases of the care model., Competing Interests: Conflict-of-interest disclosure: P.T. is on the board of directors or an advisory committee for Pfizer; has received research funding from Napp and Kyowakirin; has consulted for Novartis, Global Blood Therapeutics, and Bluebird Bio; and has received honoraria from Novartis, Global Blood Therapeutics, Apopharma, and Bluebird Bio. B.K. is on the board of directors or an advisory committee for Astra Zeneca and has received honoraria from Novartis., (© 2016 by The American Society of Hematology. All rights reserved.)

Competing Interests: Competing interests: We have read BMJ policy on competing interests and declare the following: MdM has received funding for taking part in clinical trials and advisory boards from Novartis, Pfizer, and Addmedica. She has received funding to attend academic meetings from Novartis and Addmedica. VB has received funding from Addmedica for taking part in an advisory board. SC has received funding from Novartis and Pfizer for advisory boards and other meetings. AP has received funding from Bluebirdbio for attending an advisory board. JP has received funding for from Novartis, Celgene and Bluebirdbio for attending advisory boards and clinical studies. PT has received funding from Bluebirdbio, Global Blood Therapeutics and Pfizer for attending advisory boards; Novartis and Apopharma for attending meetings; and Napp and Kyora Kirin for research studies. AV has received funding from Amgen, Pfizer, Jazz Pharmaceuticals and Medac to attend academic meetings and take part in advisory boards. DR has received funding for taking part in clinical trials and advisory boards from Novartis, Eli Lilly and Bluebirdbio. He received funding to attend academic meetings from Eli Lilly, Novartis, Biogen, and Addmedica.

Sickle cell disease is an increasing global health burden. This inherited disease is characterized by a remarkable phenotypic heterogeneity, which can only partly be explained by genetic factors. Environmental factors are likely to play an important role but studies of their impact on disease severity are limited and their results are often inconsistent. This study investigated associations between a range of environmental factors and hospital admissions of young patients with sickle cell disease in London and in Paris between 2008 and 2012. Specific analyses were conducted for subgroups of patients with different genotypes and for the main reasons for admissions. Generalized additive models and distributed lag non-linear models were used to assess the magnitude of the associations and to calculate relative risks. Some environmental factors significantly influence the numbers of hospital admissions of children with sickle cell disease, although the associations identified are complicated. Our study suggests that meteorological factors are more likely to be associated with hospital admissions for sickle cell disease than air pollutants. It confirms previous reports of risks associated with wind speed (risk ratio: 1.06/standard deviation; 95% confidence interval: 1.00-1.12) and also with rainfall (1.06/standard deviation; 95% confidence interval: 1.01-1.12). Maximum atmospheric pressure was found to be a protective factor (0.93/standard deviation; 95% confidence interval: 0.88-0.99). Weak or no associations were found with temperature. Divergent associations were identified for different genotypes or reasons for admissions, which could partly explain the lack of consistency in earlier studies. Advice to patients with sickle cell disease usually includes avoiding a range of environmental conditions that are believed to trigger acute complications, including extreme temperatures and high altitudes. Scientific evidence to support such advice is limited and sometimes confusing. This study shows that environmental factors do explain some of the variations in rates of admission to hospital with acute symptoms in sickle cell disease, but the associations are complex, and likely to be specific to different environments and the individual's exposure to them. Furthermore, this study highlights the need for prospective studies with large numbers of patients and standardized protocols across Europe., (Copyright© Ferrata Storti Foundation.)

The risk of stroke in children screened with transcranial Doppler ultrasound in the United Kingdom is not known. We evaluated a clinician-led program using a risk assessment modified from the STOP protocol. High-risk classification included abnormal velocities in the anterior cerebral artery, and single abnormal scan if initial velocity >220 cm/s (high abnormal) or if preceded by at least 2 conditional scans. In total, 1653 scans were performed in 542 children, followed for 2235 patient-years. Fifty-eight (10.7%) high-risk subjects were identified, including 18 (31%) with high abnormal, and 15 (26%) with previous conditional scans. In 2 (3%), abnormal velocity was restricted to the anterior cerebral artery. The estimated proportion of children at high risk, scanned before 6 years of age was >20%. There were 4 cases of acute ischemic stroke (AIS) and 2 of acute hemorrhagic stroke. The incidence of all stroke, AIS, and acute hemorrhagic stroke were 0.27, 0.18, and 0.09 per 100 patient-years, respectively. The proportion of children at high risk is higher than most previous estimates, partly as a result of our modified risk assessment. About 2 children per 1000 screened with transcranial Doppler ultrasound progress to AIS.

Background: A large population of older children with sickle cell disease (SCD) is currently vaccinated with only 23-valent pneumococcal polysaccharide vaccine (PPSV23). In immunocompetent adults, PPSV23 vaccination reduces immune responses to subsequent vaccination with a pneumococcal vaccine. The 13-valent pneumococcal conjugate vaccine (PCV13), which addresses this limitation, may offer an advantage to this population at high risk of pneumococcal disease., Procedure: Children with SCD 6-17 years of age previously vaccinated with PPSV23 at least 6 months before study enrollment received two doses of PCV13 6 months apart. Anti-pneumococcal polysaccharide immunoglobulin G (IgG) geometric mean concentrations (GMCs) and opsonophagocytic activity (OPA) geometric mean titers (GMTs) were measured before, 1 month after each administration, and 1 year after the second administration., Results: Following each PCV13 administration, IgG GMCs and OPA GMTs significantly increased, and antibody levels after doses 1 and 2 were generally comparable. Antibody levels declined over the year following dose 2. At 1 year after the second administration, OPA GMTs for all and IgG GMCs for most serotypes remained above pre-vaccination levels. Most adverse events were due to vaso-occlusive crises, a characteristic of the underlying condition of SCD., Conclusions: Children with SCD who were previously vaccinated with PPSV23 responded well to 1 PCV13 dose, and a second dose did not increase antibody response. PCV13 antibodies persisted above pre-vaccination levels for all serotypes 1 year after dose 2. Children with SCD may benefit from at least one dose of PCV13., (© 2015 Wiley Periodicals, Inc.)

Background and Purpose: Sickle cell anemia is associated with compromised oxygen-carrying capability of hemoglobin and a high incidence of overt and silent stroke. However, in children with no evidence of cerebral infarction, there are changes in brain morphometry relative to healthy controls, which may be related to chronic anemia and oxygen desaturation., Methods: A whole-brain tract-based spatial statistics analysis was carried out in 25 children with sickle cell anemia with no evidence of abnormality on T2-weighted magnetic resonance imaging (13 male, age range: 8-18 years) and 14 age- and race-matched controls (7 male, age range: 10-19 years) to determine the extent of white matter injury. The hypotheses that white matter damage is related to daytime peripheral oxygen saturation and steady-state hemoglobin were tested., Results: Fractional anisotropy was found to be significantly lower in patients in the subcortical white matter (corticospinal tract and cerebellum), whereas mean diffusivity and radial diffusivity were higher in patients in widespread areas. There was a significant negative relationship between radial diffusivity and oxygen saturation (P<0.05) in the anterior corpus callosum and a trend-level negative relationship between radial diffusivity and hemoglobin (P<0.1) in the midbody of the corpus callosum., Conclusions: These data show widespread white matter abnormalities in a sample of asymptomatic children with sickle cell anemia, and provides for the first time direct evidence of a relationship between brain microstructure and markers of disease severity (eg, peripheral oxygen saturation and steady-state hemoglobin). This study suggests that diffusion tensor imaging metrics may serve as a biomarker for future trials of reducing hypoxic exposure., (© 2015 American Heart Association, Inc.)

Deferasirox (DFX) has been licensed for iron chelation in patients with sickle cell disease (SCD), but there is limited data on its long-term efficacy and safety in children. This retrospective study included 62 regularly transfused children managed in the East London and Essex Clinical Haemoglobinopathy Network (mean age 9.2 ± 3.2 yr). Efficacy measurements consisted of monthly serum ferritin (SF) and annual R2 MRI-estimated liver iron concentration (LIC), and safety markers included serum creatinine and alanine aminotransferase (ALT). The mean duration of DFX treatment was 2.5 ± 1.4 yr, and mean dose at 36 months was 25 mg/kg/d. Mean SF at initiation of treatment was 2542 ± 952 ng/mL and increased to 4691 ± 2255 ng/mL at 36 months (P = 0.05). Mean LIC on first scan was 10.3 mg/g dry weight and did not decrease significantly on follow-up scans. There was a significant correlation between relative change in LIC and in SF (R(2) = 0.66, P < 0.001). Reversible transaminitis episodes, probably due to drug-induced hepatitis, were noted in 53% of patients. Responses to an adherence and acceptability questionnaire indicated that more than 50% of children had difficulties in taking DFX, commonly because of unpleasant taste. Our results show that more than 50% of children with SCD have inadequate control of iron overload with DFX. It is not clear whether this is because of frequent dose interruptions, poor tolerability and adherence, or poor efficacy of the drug. We recommend further studies to confirm these findings and to optimise iron chelation in this population., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Chronic red blood cell (RBC) transfusion is employed for a wide range of sickle cell disease complications, ranging from primary and secondary stroke prophylaxis to prevention of painful vaso-occlusive episodes. Currently different methods are employed by centers for chronic transfusion that include simple, automated and partial manual RBC exchange transfusion. A retrospective cohort study of two different manual RBC exchange transfusion methods was conducted between two comprehensive care centers in Toronto, ON, Canada and London, United Kingdom in 19 and 21 sickle cell disease adults, respectively. London used a weight-based protocol, while Toronto used a unit-based method. Our results indicated that sickle cell disease patients utilizing a weight-based method are more often unable to achieve the prescribed Hb S (HBB: c.20A > T) target compared to the unit-based method (90.0 vs. 53.0% in the weight-based and unit-based methods, respectively, p = 0.0123). On multivariable logistic regression, none of the covariates examined was found to influence the ability to achieve the prescribed Hb S target after accounting for the exchange transfusion method. Mean interval of exchange sessions, session duration, total units of packed RBC, volume of blood used by body weight each year, the mean post exchange hematocrit [or packed cell volume (PCV)] and ferritin change were similar in both cohorts. In conclusion, the unit-based method was more effective at maintaining the prescribed Hb S target.

Blood transfusion and iron chelation currently represent a supportive therapy to manage anemia, vasculopathy and vaso-occlusion crises in Sickle-Cell-Disease. Here we describe the first 5-year long-term randomized clinical trial comparing Deferiprone versus Deferoxamine in patients with Sickle-Cell-Disease. The results of this study show that Deferiprone has the same effectiveness as Deferoxamine in decreasing body iron burden, measured as repeated measurements of serum ferritin concentrations on the same patient over 5-years and analyzed according to the linear mixed-effects model (LMM) (p=0.822). Both chelators are able to decrease, significantly, serum ferritin concentrations, during 5-years, without any effect on safety (p=0.005). Moreover, although the basal serum ferritin levels were higher in transfused compared with non-transfused group (p=0.031), the changes over time in serum ferritin levels were not statistically significantly different between transfused and non-transfused cohort of patients (p=0.389). Kaplan-Meier curve, during 5-years of study, suggests that Deferiprone does not alter survival in comparison with Deferoxamine (p=0.38). In conclusion, long-term iron chelation therapy with Deferiprone was associated with efficacy and safety similar to that of Deferoxamine. Therefore, in patients with Sickle-Cell-Disease, Deferiprone may represent an effective long-term treatment option., (Copyright © 2014. Published by Elsevier Inc.)

Management of the acute painful crisis (APC) of sickle cell disease (SCD) remains unsatisfactory despite advances in the understanding and management of acute pain in other clinical settings. One reason for this is an unsophisticated approach to the use of opioid analgesics for pain management. This applies to haematologists who are responsible for developing acute sickle pain management protocols for their patients, and to health care staff in the acute care setting. The objective of this article is to evaluate the evidence for use of opioids in APC management. We have highlighted the possibilities for improving management by using alternatives to morphine, and intranasal (IN) or transmucosal routes of administration for rapid onset of analgesia in the emergency department (ED). We suggest how experience gained in managing acute sickle pain in children could be extrapolated to adolescents and young adults. We have also questioned whether patients given strong opioids in the acute setting are being safely monitored and what resources are required to ensure efficacy, safety and patient satisfaction. We also identify aspects of care where there are significant differences of opinion, which require further study by randomized controlled trial., (© 2014 John Wiley & Sons Ltd.)

Transcranial Doppler (TCD) ultrasonography helps to identify children with sickle cell disease (SCD) who are at an increased risk of stroke,making primary stroke prevention a reality. A cross-sectional study of145 Nigerian children aged ≥3 years with SCD was carried out to describe the pattern of cerebral blood flow (CBF) abnormalities. The mean time-averaged mean velocity (TAMV) was 152 ±27.0 cm/sec and122 ±22.0 cm/sec in Hb SS and Hb S1C group, respectively. Abnormal velocities were recorded in six (4.7%) of the Hb SS patients and none of the Hb S1C while conditional risk (CR) velocities were recorded in 19.7% of Hb SS (low conditional 11.0%, high conditional 8.7%) and low conditional in 5.6% of Hb S1C cases. Cerebral flow velocities showed a negative correlation with age and hematocrit. Compared with African-American children, Nigerian children with Hb SS disease have a considerably higher prevalence of CR velocities.

The painful crisis is the commonest acute presentation of sickle cell disease (SCD), yet effective pain control in hospital is often delayed, inadequate and dependent on injected opiates. Intranasal diamorphine (IND) has been used in paediatric emergency departments for management of acute pain associated with fractures, but the analgesic effect is short lived. We evaluated its efficacy and safety when given in combination with intravenous or oral morphine for rapid analgesia for children presenting to our emergency department with painful crisis of SCD. In phase 1, nine patients received IND plus intravenous morphine. In phase 2, 13 received IND plus oral morphine. There was a rapid improvement in pain score; the proportions in severe pain at t = 0, 15, 30 and 120 minutes in phase 1 were 78%, 11%, 0% and 11%, respectively; in phase 2, 77%, 30%, 15% and 0%, respectively. There were no serious side effects and questionnaire scores indicated that children found IND effective and acceptable. IND can be recommended for acute control of sickle pain in children presenting to hospital.

Children with sickle cell disease (SCD) are at high risk of severe infection with Streptococcus pneumoniae (SP). From 2002, all children aged <5 years in the UK with SCD were recommended 7-valent pneumococcal conjugate vaccine (PCV-7) in infancy and 23-valent pneumococcal polysaccharide vaccine boosting, in addition to regular penicillin prophylaxis. Our objective was to determine the nasopharyngeal (NP) carriage rate of SP in children aged <5 years with SCD before and after vaccination with PCV-7 (by vaccine, cross-protection and non-vaccine serotypes). NP swabs were obtained from 63 children attending the Royal London Hospital or Newham General Hospital paediatric haematology clinic between April 2001 and April 2002. Later, NP swabs were obtained from 43 children attending the clinic between June and December 2004 after a PCV-7 vaccination programme. All SP isolated by culture were serotyped and susceptibility to penicillin measured. In the first study group, 13 samples grew SP with 1 sample containing 2 different serotypes, giving a carriage rate of 21%. Four (31%) were intermediately susceptible to penicillin. In the second group overall NP carriage rate had decreased to 9% (n=4), and the proportion directly or indirectly covered by the PCV-7 vaccine fell from 13/14 to 2/4 (P=0.11). One (25%) of these isolates was intermediately susceptible to penicillin. The introduction of PCV-7 appears to be associated with a shift in distribution of serotypes carried by children with SCD. This may have implications for vaccine effectiveness.

Background and Objectives: We investigated outcomes in a UK neonatal cohort as a benchmark for care of children with sickle cell disease (SCD)., Design and Methods: Two-hundred and fifty-two children (180 with hemoglobin [Hb] SS, 64 with HbSC, and 8 with HbS/beta thalassemia), identified during 1983-2005 by universal birth screening in East London, were followed in a hospital and community-based program which included penicillin V prophylaxis from 3 months of age, 23-valent pneumococcal polysaccharide vaccine from 1993, conjugate pneumococcal vaccine from 2002 and transcranial Doppler screening from 1991., Results: At the end of 2005, there were 2158 patient years of observation. The median age of the patients was 7.8 (interquartile range 3.3-13.0) years, and 2.8% of those enrolled had been lost to follow-up. The estimated survival of children with HbSS at 16 years was 99.0% (95% confidence interval, CI, 93.2 to 99.9%) and pneumococcal sepsis rate was 0.3 (95% CI 0.1-0.8) episodes per 100 patient-years. The risk of overt stroke was 4.3% (95%CI 1.5 to 11.4%) and could be further reduced by transcranial Doppler screening from infancy and transfusing all children with high-risk scans. No deaths, strokes or episodes of pneumococcal sepsis were observed in children with HbSC or HbS/beta thalassemia. The mortality rates from HbSS were significantly lower than those in other reported cohorts., Interpretation and Conclusions: Mortality in childhood SCD can virtually be eliminated in a well-resourced health service setting linking community-based care with a specialized, hospital-based center. SCD continues to cause substantial morbidity from acute complications and chronic organ damage. We recommend setting up of clinical networks to optimize the management of SCD.

Objective: Sickle cell disease (SCD) is associated with cerebrovascular disease, cerebral infarction, and cognitive dysfunction. This study aimed to detect the presence and extent of white matter abnormalities in individuals with SCD using voxel-based morphometry (VBM)., Methods: Thirty-six children and adolescents with SCD (age range, 9-24 years) and 31 controls (8-25 years) underwent magnetic resonance investigations using T1- and T2-weighted protocols. White and gray matter density maps were obtained from three-dimensional magnetic resonance imaging (MRI) data sets. Using VBM, we compared the maps between controls and SCD individuals with silent white matter infarct lesions (SCD+L; n = 16), and those without visible abnormality (SCD-L; n = 20)., Results: In comparison with controls, intelligence quotients (IQs) were lower in both SCD groups irrespective of presence of visible lesions. VBM showed widespread bilateral white matter abnormalities in the SCD+L group, extending beyond the regions of focal infarction in the deep anterior and posterior white matter borderzones. Bilateral white matter abnormalities were also observed in the SCD-L group, in locations similar to those in the SCD+L group., Interpretation: VBM is sensitive to detection of widespread white matter injury in SCD patients in borderzones between arterial territories even in the absence of evidence of infarction. Those changes may contribute to cognitive deficits in this population.

Objectives: Research is needed to enable more effective assessment and treatment of analgesic addiction among patients with painful chronic illnesses and to improve our understanding of the staff-patient interactions that give rise to pseudoaddiction. This study tested predictions that certain drug-use behaviors and pain-coping strategies were associated with analgesic addiction, and that certain were associated with risk of pseudoaddiction., Methods: Analgesic addiction and risk of pseudoaddiction among patients with sickle cell disease were measured by symptom counts, using an interview method for classifying symptoms as pain-related (pseudoaddiction) or non-pain-related (analgesic addiction). Concern-raising drug-use behaviors and treatment requirements for pain were also assessed, and participants completed the pain-coping strategies questionnaire. Qualitative case descriptions of patients meeting criteria for analgesic addiction and pseudoaddiction were examined to identify common and distinctive features of the two groups., Results: Consistent with predictions, multiple regression analyses showed that disputes about analgesics were independently associated with risk of pseudoaddiction. Physiological dependence and illicit drug use were both associated with analgesic addiction, independently of other factors. The qualitative data showed that analgesic addiction was not an obvious, clear-cut phenomenon: addiction and pseudoaddiction were superficially similar, and even symptoms of genuine addiction originated in patients' experiences of pain and illness., Conclusions: These tentative findings were broadly consistent with what is known about analgesic addiction and pseudoaddiction in other painful conditions. They also suggested that current recommendations about addiction in pain patients could understate the potential importance of physiological dependence. The findings could inform staff training programs to improve pain management and reduce the incidence of pseudoaddiction. The classification of pain-related and non-pain-related symptoms could be used in further research on the development of analgesic addiction and the factors that influence staff attributions about addiction in patients with pain.

This study aimed to investigate whether infants with sickle cell anaemia (SCA) are at risk of neurodevelopmental delay, and whether any delay is associated with SCA pathology. Twenty-eight infants (14 SCA; 14 age- and ethnic-similar controls) were assessed longitudinally with the Bayley Infant Neurodevelopmental Screener (BINS) at 3, 9 and 12 months. Transcranial Doppler (TCD) and pulse oximetry (SpO2) measures were recorded longitudinally in SCA infants, and a subgroup of controls. Haemoglobin values were obtained from SCA infants. At each age, SCA infants obtained BINS scores indicative of greater risk of neurodevelopmental delay compared with controls. The number of moderate-high BINS risk scores increased significantly between 3 and 9 months. At 9 months BINS raw scores correlated negatively with TCD velocity and positively with haemoglobin. This exploratory study suggests that SCA infants may be at greater risk of neurodevelopmental delay than previously considered, and may provide the impetus for further research into the very early precursors of cognitive impairment.

Treatment of painful episodes in sickle cell disease (SCD) is sometimes complicated by disputes between patients and staff and patient behaviors that raise concerns about analgesic misuse. Those concern-raising behaviors could indicate either drug seeking caused by analgesic dependence or pseudoaddiction caused by undertreatment of pain. To make a systematic assessment of concern-raising behaviors and examine their associations with other factors, including DSM-IV symptoms of substance dependence, individual, in-depth interviews with SCD patients were conducted to apply pre-established criteria for concern-raising behaviors. These included disputes with staff tampering with analgesic delivery systems, passing prescribed analgesics from one person to another, being suspected or accused of analgesic misuse, self-discharging from hospital, obtaining analgesic prescriptions from multiple sources, using illicit drugs, and injecting analgesics. Assessments were also made of pain-related symptoms of substance dependence (where behaviors resemble substance dependence but reflect attempts to manage pain, increasing the risk of pseudoaddiction), non-pain-related symptoms of substance dependence (where substance dependence reflects analgesic use beyond pain management), and pain coping strategies (using the Pain Coping Strategies Questionnaire). Inter-rater reliability for the assessment of concern-raising behaviors was high, with Kappa coefficients of 0.63 to 1.0. The most frequent concern-raising behaviors were disputes with staff about pain or analgesics. The least frequent were tampering with analgesic delivery systems and passing analgesics between patients in hospital. The odds of concern-raising behaviors in hospital were raised eightfold by less use of ignoring pain as a coping strategy, and more than doubled by each additional pain-related symptom of substance dependence. Non-pain-related symptoms of substance dependence had no independent effect on concern-raising behaviors. Concern-raising behaviors were more closely associated with pain behaviors that make patients vulnerable to misperceptions of substance dependence than they were with genuine substance dependence. The results show how pseudoaddiction can adversely influence hospital pain management, and suggest that more emphasis should be placed on patients' pain and analgesic needs when responding to concern-raising behaviors in hospital.

Concerns about dependence on prescribed analgesia may compromise pain management, but there was previously little reliable evidence about substance dependence among patients with sickle cell disease (SCD). We conducted in-depth, semi-structured interviews with SCD patients in London, UK, to assess DSM-IV symptoms of substance dependence and abuse. Criteria were applied to differentiate between pain-related symptoms, which corresponded to the DSM-IV symptoms but involved analgesics used to control pain, and non-pain-related symptoms, which involved analgesic use beyond pain management. Pain-related symptoms are informative about how the pattern of recurrent acute pain in SCD may make patients vulnerable to perceptions of drug dependence. Non-pain-related symptoms are informative about more stringently defined dependence on analgesia in SCD. Inter-rater reliability was high, with mean Kappa coefficients of 0.67-0.88. The criteria could be used to assess analgesic dependence in other painful conditions. Pain-related symptoms were more frequent, accounting for 88% of all symptoms reported. When pain-related symptoms were included in the assessment, 31% of the sample met the DSM-IV criteria for substance dependence, compared with only 2% when the assessment was restricted to non-pain-related symptoms. Qualitative analysis of participants' descriptions of analgesic use showed that active coping attempts (attempts to anticipate pain and avoid hospital admissions) and awareness of dependence were themes in descriptions of both pain-related and non-pain-related symptoms. Seeking a more normal lifestyle and impaired activities were themes associated with pain-related symptoms. Psychological disturbance was a theme associated with non-pain-related symptoms. The implications are for more responsive treatment of pain in SCD and greater awareness of how patients' pain coping may be perceived as analgesic dependence. Further research could examine ways that pain-related and non-pain-related symptoms of dependence may be associated with other pain coping strategies and with the outcomes of treatment for painful episodes in hospital.

Background: An atypical form of life-threatening hemolytic transfusion reaction (HTR) in patients with sickle cell disease (SCD) has been well described in the literature. Continuation of blood transfusion may be lethal, as it can further exacerbate hemolysis. The pathophysiologic mechanism of HTR is not well understood., Case Reports: Two cases of severe HTR in SCD after the transfusion of compatible RBC units are reported. Hemolysis of both autologous and transfused cells was documented in Case 1 by urine Hb high-performance liquid chromotography. Multispecific HLA antibodies were identified in Case 1. Reticulocytopenia was noted in both cases during the acute hemolytic process. This was followed by a rise in reticulocyte count during receipt of IVIG and steroid therapy. Bone marrow examination during reticulocytopenia in Case 2 showed erythroid hyperplasia., Conclusion: In SCD, both mature sickle cells and sickle reticulocytes adhere more readily to macrophages. In view of the bone marrow aspiration results, it appears that the recipients' HbS cells are destroyed by hyperactive macrophages and that the reticulocytopenia observed during HTR is likely to be due to peripheral consumption (i.e., destruction by macrophages), rather than suppression of erythropoiesis. Cessation of hemolysis during IVIG and steroid treatment may be due to IVIG's blocking of the adhesion of sickle cells and reticulocytes to macrophages, together with steroid suppression of macrophage activity.