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Summary: Despite recent developmental screening guidelines, rates of neurodevelopmental disorders (NDDs) remain lower than expected in children with sickle cell disease (SCD). A retrospective chart review identified 276 eligible patients; 214 charts were available for developmental screening and 207 charts for autism‐specific screening. Developmental surveillance/screening was conducted in 70% of charts and autism‐specific screening in 19% of charts. Validated tools were used in 32% of developmental screenings and 92% of autism‐specific screenings. Many children (57%) were screened outside recommended ages. In conclusion, children with SCD are not regularly receiving appropriate developmental screening and surveillance by their healthcare providers. [ABSTRACT FROM AUTHOR]

Background: Blood–brain barrier (BBB) disruption may lead to endothelium dysfunction and inflammation in sickle cell disease (SCD). However, abnormalities of BBB in SCD, especially in pediatric patients for whom contrast agent administration less than optimal, have not been fully characterized. Purpose: To examine BBB permeability to water in a group of pediatric SCD participants using a non‐invasive magnetic resonance imaging technique. We hypothesized that SCD participants will have increased BBB permeability. Study Type: Prospective cross‐sectional. Population: Twenty‐six pediatric participants (10 ± 1 years, 15F/11M) were enrolled, including 21 SCD participants and 5 sickle cell trait (SCT) participants, who were siblings of SCD patients. Field Strength/Sequence: 3 T. Water extraction with phase‐contrast arterial spin tagging with echo‐planer imaging, phase‐contrast and T1‐weighted magnetization‐prepared rapid acquisition of gradient echo. Assessment: Water extraction fraction (E), BBB permeability‐surface area product (PS), cerebral blood flow, hematological measures (hemoglobin, hematocrit, hemoglobin S), neuropsychological scores (including domains of intellectual ability, attention and executive function, academic achievement and adaptive function, and a composite score). Regions of interest were drawn by Z.L. (6 years of experience). Statistical Tests: Wilcoxon rank sum test and chi‐square test for group comparison of demographics. Multiple linear regression analysis of PS with diagnostic category (SCD or SCT), hematological measures, and neuropsychological scores. A two‐tailed P value of 0.05 or less was considered statistically significant. Results: Compared with SCT participants, SCD participants had a significantly higher BBB permeability to water (SCD: 207.0 ± 33.3 mL/100 g/minute, SCT: 171.2 ± 27.2 mL/100 g/minute). SCD participants with typically more severe phenotypes also had a significantly leakier BBB than those with typically milder phenotypes (severe: 217.3 ± 31.7 mL/100 g/minute, mild: 193.3 ± 31.8 mL/100 g/minute). Furthermore, more severe BBB disruption was associated with worse hematological symptoms, including lower hemoglobin concentrations (β = −8.84, 95% confidence interval [CI] [−14.69, −3.00]), lower hematocrits (β = −2.96, 95% CI [−4.84, −1.08]), and higher hemoglobin S fraction (β = 0.77, 95% CI [0.014, 1.53]). Data Conclusion: These findings support a potential role for BBB dysfunction in SCD pathogenesis of ischemic injury. Level of Evidence: 2 Technical Efficacy: Stage 2 [ABSTRACT FROM AUTHOR]

Sickle cell disease (SCD) is an inherited hemoglobinopathy with an increased risk of neurological complications. Due to anemia and other factors related to the underlying hemoglobinopathy, cerebral blood flow (CBF) increases as compensation; however, the nature of alterations in oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO2) in SCD remains controversial, largely attributed to the different calibration models. In addition, limited studies have been done to investigate oxygen metabolism in pediatric patients. Thus, this study used a non-invasive T2-based MR oximetry, T2-Relaxation-Under-Spin-Tagging (TRUST) MRI, to measure oxygen homeostasis in pediatric patients with SCD using four different calibration models and examined its relationship to hematological measures. It was found that, compared with controls, SCD patients showed an increased CBF, unchanged total oxygen delivery and increased venous blood T2. The results of OEF and CMRO2 were dependent on the calibration models used. When using sickle-specific, hemoglobin S (HbS) level-dependent calibration, there was a decreased OEF and CMRO2, while the bovine model showed an opposite result. OEF and CMRO2 were also associated with hemoglobin and HbS level; the direction of the relationship was again dependent on the model. Future studies with in vivo calibration are needed to provide more accurate information on the T2-Y v relationship. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background. Children with sickle cell disease have an increased risk of neurodevelopmental disorders such as attention deficit hyperactivity disorder, intellectual disability, and specific learning disabilities. Little research has been done to characterize the sickle cell disease–related characteristics associated with neurodevelopmental disorders in the sickle cell disease population. Methods. This study was a retrospective chart review involving the outpatient records of 2 medical centers, Kennedy Krieger Institute and Johns Hopkins Hospital. Participants in the study included 59 children with sickle cell disease with a documented neurodevelopmental diagnosis, specifically attention deficit hyperactivity disorder, attention issues, behavioral issues, executive dysfunction, specific learning disabilities in math, reading, and reading comprehension, intellectual disabilities, developmental delay, fine motor disorders, language disorders, or autism spectrum disorders. Results. Children with sickle cell disease type hemoglobin S-β thalassemia plus had significantly higher odds of attention issues than children with sickle cell disease type hemoglobin SS (OR = 17.0, 95% CI = 1.99-145.00, P < .02). Children with sickle cell disease and a reported history of asthma had significantly higher odds of behavioral issues than children with sickle cell disease without a history of asthma, after adjustment for gender and sickle cell disease type (exact OR = 19.53, 95% CI = 1.16-1369.72, P < .04). Conclusion. Children with sickle cell disease may have increased risk for certain neurodevelopmental diagnoses based on their disease characteristics and associated comorbidities. These preliminary study results should be explored in a larger database. [ABSTRACT FROM AUTHOR]

Unlabelled: The purpose of this study was to develop and validate a brief, clinically relevant, multidimensional interview to assess pain burden among children and adolescents with sickle cell disease (SCD). The Sickle Cell Disease Pain Burden Interview-Youth (SCPBI-Y) was developed using a panel of experts, patients, and caregivers. Validation was undertaken with children and youth with SCD, ages 7 to 21 years (N = 129), recruited from 4 urban children's hospitals. Participants were recruited from inpatient (n = 62) and outpatient (n = 67) settings. The SCPBI-Y demonstrated strong internal consistency reliability, cross-informant concordance (child-caregiver), and test-retest reliability (outpatient setting). Moderate construct validity was found with validated measures of functional ability, pain, and quality of life. The SCPBI-Y demonstrated construct validity using a contrasted group approach between youth in inpatient versus outpatient settings and by severity of SCD symptoms, suggesting that youth in inpatient settings and with higher disease severity exhibited greater pain burden. Discriminant validity was found between SCPBI-Y and mood. Our preliminary findings suggest that the SCPBI-Y is a valid and reliable multidimensional interview that can be used in different clinical settings to evaluate pain burden among children and adolescents with SCD.Perspective: Multifaceted pain assessments are salient in providing optimal care to children and adolescents with SCD; however, current evaluations are lengthy and cumbersome to administer clinically. The current study introduces and validates a brief, clinically useful multidimensional interview to evaluate pain burden specific to youth with SCD. [ABSTRACT FROM AUTHOR]

Background: A doctor’s diagnosis of asthma is associated with increased morbidity (pain and acute chest syndrome [ACS]) among children with sickle cell disease (SCD). An association between IgE levels and asthma and morbidity has not been investigated in children with SCD. Objective: We tested the hypothesis that elevated total and allergen-specific IgE levels are associated with asthma and SCD morbidity in children with SCD. Methods: A cross-sectional study of children with SCD who participated in the Silent Cerebral Infarct Trial was conducted. Logistic regression and negative binomial regression were used to investigate potential associations of total and allergen-specific IgE levels with asthma diagnosis and SCD morbidity, both confirmed by medical record review. Elevation of total IgE level was defined as age-adjusted and sex-adjusted IgE level exceeding the 90th percentile compared with a nonatopic reference population. IgE antibody positivity to Alternaria alternata (mold), Blattella germanica (cockroach), and Dermatophagoides pteronyssinus (dust mite) was assessed by ImmunoCAP analysis. Results: Children with SCD (140 with asthma; 381 without asthma) were evaluated. Elevations in total IgE level (P = .04) and IgE antibody specific for Alternaria alternata (P = .0003), Blattella germanica (P = .008), and Dermatophagoides pteronyssinus (P = .01) were associated with asthma. ACS (P = .048) but not pain (P = .20) was associated with total IgE level, but neither was associated with specific IgE levels. Conclusion: Significantly increased levels of total and allergen-specific IgE levels are associated with asthma in SCD. High IgE levels are a risk factor for ACS but not pain rates. [ABSTRACT FROM AUTHOR]

We describe previously transfused patients with sickle cell disease (n = 6) and thalassemia (n = 1) who received nonmyeloablative hematopoietic stem cell transplantation (HCT) to induce stable (full or partial) donor engraftment. Patients were 3 to 20 years (median, 9 years) old. All 7 received pretransplantation fludarabine and 200 cGy of total body irradiation; 2 patients also received horse antithymocyte globulin. Patients received bone marrow (n = 6) or peripheral blood stem cells (n = 1) from HLA-identical siblings, followed by a combination of mycophenolate mofetil and cyclosporine or tacrolimus for postgrafting immunosuppression. After nonmyeloablative HCT, absolute neutrophil counts were <0.5 × 109/L and <0.2 × 109/L for a median of 5 days (range, 0–13 days) and 0 days (range 0–13 days), respectively. A median of 0 (range, 0–9) platelet transfusions were administered. No grade IV nonhematologic toxicities were observed. One patient experienced grade II acute graft-versus-host disease. Two months after transplantation, 6 of 7 patients had evidence of donor chimerism (range, 25%–85%). Independent of red blood cell transfusions, these 6 patients initially had increased total hemoglobin and hemoglobin A concentrations and a reduction of reticulocytosis and transfusion requirements. There were no complications attributable to sickle cell disease during the interval of transient mixed chimerism. However, after posttransplantation immunosuppression was tapered, there was loss of the donor graft, and all patients experienced autologous hematopoietic recovery and disease recurrence. One patient did not engraft. The duration of transient mixed chimerism ranged from 97 to 441 days after transplantation in patients 4 and 6, respectively, and persisted until immunosuppressive drugs were discontinued after transplantation. In summary, the nonmyeloablative HCT regimens described here produced minimal toxicity and resulted in transient donor engraftment in 6 of 7 patients with hemoglobinopathies. Although complications from the underlying hemoglobinopathies did not occur during the period of mixed chimerism, these results suggest that stable (full or partial) donor engraftment after nonmyeloablative HCT is more difficult to achieve among immunocompetent pediatric patients with hemoglobinopathies than among adults with hematologic malignancies, perhaps in part because recipients may have been sensitized to minor histocompatibility antigens of their donor by preceding blood transfusions. [Copyright &y& Elsevier]

The article discusses the study on the relationship between thrombospondin-1 and L-selection with silent cerebral infarct in children with sickle cell anaemia. It states that baseline characteristics were similar between silent cerebral infraction (SCI) and non-SCI. It cites that patients with sickle cell anaemia (SCA) are at risk for increased inflammatory response. It also mentions that children with SCA are at risk of chronic and intermittent acute cerebral ischaemia events.

OBJECTIVE: Children with sickle cell disease (SCD) are considered to be at high risk for complications from influenza infection despite minimal published data that characterize the burden of influenza in this population. Our objectives were to (1) estimate the rate of influenzarelated hospitalizations (IRHs) among children with SCD, (2) compare this rate with rates of children with cystic fibrosis (CE) and children with neither SCD nor CF, and (3) explore mechanisms that underlie these potentially preventable hospitalizations. METHODS: We analyzed hospitalizations from 4 states (California, Florida, Maryland, and New York) across 2 influenza seasons (2003-2004 and 2004-2005) from the Healthcare Cost and Utilization Project State Inpatient Databases. We included hospitalizations with a discharge diagnosis code for influenza in a child <18 years of age. We used census data and disease prevalence estimates to calculate denominators and compare rates of IRH among children with SCD, CE, and neither disease. RESULTS: There were 7896 pediatric IRHs during the 2 influenza seasons. Of these, 159 (2.0%) included a co-occurring diagnosis of SCD. Annual rates of IRHs were 112 and 2.0 per 10000 children with and without SCD, respectively, across both seasons. Children with SCD were hospitalized with influenza at 56 times (95% confidence interval: 48-65) the rate of children without SCD. Children with SCD had approximately double the risk of IRH compared with children with CF (risk ratio: 2.1 [95% confidence interval: 1.5-2.9]). IRHs among children with SCD were not longer, more costly, or more severe than IRHs among children without SCD; they were also rarely nosocomial and cooccurred with a diagnosis of asthma in 14% of cases. CONCLUSIONS: IRHs are substantially more common among children with SCD than among those without the disease, which supports the potential importance of vigorous influenza vaccination efforts that target children with SCD. [ABSTRACT FROM AUTHOR]

The pathophysiology of sickle cell disease (SCD) is dependent on the polymerization of deoxygenated sickle hemoglobin (HbS), leading to erythrocyte deformation (sickling) and vaso-occlusion within the microvasculature. Following deoxygenation, there is a delay time before polymerization is initiated, during which nucleation of HbS monomers occurs. An agent with the ability to extend this delay time or slow polymerization would therefore hold a therapeutic, possibly curative, potential. We used the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) method to screen for HbS-binding RNA aptamers modified with nuclease-resistant 2′-fluoropyrimidines. Polymerization assays were employed to identify aptamers with polymerization-inhibitory properties. Two noncompeting aptamers, DE3A and OX3B, were found to bind hemoglobin, significantly increase the delay time, and reduce the rate of polymerization of HbS. These modifiable, nuclease-resistant aptamers are potential new therapeutic agents for SCD. [ABSTRACT FROM AUTHOR]

BACKGROUND AND OBJECTIVE: Susceptibility to encapsulated bacteria is well known in sickle cell disease (SCD). Hydroxyurea use is common in adults and children with SCD, but little is known about hydroxyurea’s effects on immune function in SCD. Because hydroxyurea inhibits ribonucleotide reductase, causing cell cycle arrest at the G1-S interface, we postulated that hydroxyurea might delay transition from naive to memory T cells, with inhibition of immunologic maturation and vaccine responses. METHODS: T-cell subsets, naive and memory T cells, and antibody responses to pneumococcal and measles, mumps, and rubella vaccines were measured among participants in a multicenter, randomized, double-blind, placebo-controlled trial of hydroxyurea in infants and young children with SCD (BABY HUG). RESULTS: Compared with placebo, hydroxyurea treatment resulted in significantly lower total lymphocyte, CD4, and memory T-cell counts; however, these numbers were still within the range of historical healthy controls. Antibody responses to pneumococcal vaccination were not affected, but a delay in achieving protective measles antibody levels occurred in the hydroxyurea group. Antibody levels to measles, mumps, and rubella showed no differences between groups at exit, indicating that effective immunization can be achieved despite hydroxyurea use. CONCLUSIONS: Hydroxyurea does not appear to have significant deleterious effects on the immune function of infants and children with SCD. Additional assessments of lymphocyte parameters of hydroxyurea-treated children may be warranted. No changes in current immunization schedules are recommended; however, for endemic disease or epidemics, adherence to accelerated immunization schedules for the measles, mumps, and rubella vaccine should be reinforced. [ABSTRACT FROM AUTHOR]

BACKGROUND: Growth impairment is a known complication of sickle cell disease. Effects of hydroxyurea (HU) on growth in very young children are not known. METHODS: Height, weight, BMI, and head circumference (HC) were compared with World Health Organization (WHO) standards in BABY HUG, a multicenter, randomized, double-blinded, placebo-controlled 2-year clinical trial of HU in 193 children 9 to 18 months of age. Anthropometric data were closely monitored and converted to z scores by using WHO standardized algorithms for descriptive analyses. The treatment and placebo groups were compared longitudinally by using a mixed model analysis. RESULTS: At entry, the z scores of BABY HUG children were higher than WHO norms. After 2 years of HU or placebo treatment, there were no significant differences between the groups, except for the mean HC z scores at study exit (HU: +0.8 versus placebo: +1.0, P = .05). Baseline z scores were the best predictors of z scores at study exit. The absolute neutrophil count, absolute reticulocyte count, and total white blood cell count had significant negative correlations with growth measures. CONCLUSIONS: Both groups had normal or near normal anthropometric measures during the study. The HC z scores at study entry and exit were slightly greater than WHO norms. Higher baseline white blood cell count, absolute reticulocyte count, and absolute neutrophil count were associated with poorer growth. The significance of the slightly lower HC in the treatment group at study exit is not clear. Trends toward normalization of weight and height and effects on HC will be monitored in ongoing BABY HUG follow-up studies. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We describe the prevalence and range of incidental intracranial abnormalities identified through MRI of the brain in a large group of children screened for a clinical trial. METHODS: We included 953 children between 5 and 14 years of age who were screened with MRI of the brain for the Silent Infarct Transfusion Trial. All had sickle cell anemia or sickle /3-null thalassemia. MRI scans were interpreted by 3 neuroradiologists. MRI scans reported to have any abnormality were reviewed by 2 study neuroradiologists. Incidental findings were classified into 4 categories,that is, no, routine, urgent, or immediate referral recommended. Cerebral infarctions and vascular lesions were not considered incidental and were excluded. RESULTS: We identified 63 children (6.6% [95% confidence interval: 5.1%-8.4%]) with 68 incidental intracranial MRI findings. Findings were classified as urgent in 6 cases (0.6%), routine in 25 cases (2.6%), and no referral required in 32 cases (3.4%). No children required immediate referral. Two children with urgent findings underwent surgery in the subsequent 6 months. CONCLUSION: In this large cohort of children, incidental intracranial findings were identified for 6.6%, with potentially serious or urgent findings for 0.6%. [ABSTRACT FROM AUTHOR]

OBJECTIVES. Primary hemorrhagic stroke is an uncommon complication of sickle cell disease, with reported mortality rates of 24% to 65%. Most reported cases are in adults; little is known about its occurrence in children. Proposed risk factors include previous ischemic stroke, aneurysms, low steady-state hemoglobin, high steady-state leukocyte count, acute chest syndrome, and hypertransfusion. We performed a retrospective case-control study to evaluate risk and prognostic factors for primary hemorrhagic stroke among children with sickle cell disease. PATIENTS AND METHODS. Case subjects (sickle cell disease and primary hemorrhagic stroke) and control subjects (sickle cell disease and ischemic stroke) were identified at 2 children's hospitals from January 1979 to December 2004 by reviewing divisional records and the discharge databases. RESULTS. We identified 15 case subjects (mean age: 10.4 ± 1.3 years) and 29 control subjects (mean age: 5.2 ± 0.4 years). An increased risk of hemorrhagic stroke was associated with a history of hypertension and recent (in the last 14 days) transfusion, treatment with corticosteroids, and possibly nonsteroidal antiinflammatory drugs. Average blood pressures at well visits (adjusted for age and gender) were similar between the 2 groups, suggesting that hypertension was intermittent CONCLUSIONS. In this group of children with sickle cell disease, hemorrhagic stroke was associated with a history of hypertension or antecedent events including transfusion or treatment with corticosteroids. Improved understanding of risk and prognostic factors, especially those that are modifiable, may help prevent this devastating complication in children with sickle cell disease. [ABSTRACT FROM AUTHOR]