Sulfamethoxazole-Trimethoprim Prophylaxis in Pediatric Oncology Patients With Glucose-6-Phosphate Dehydrogenase Deficiency.

We sought to determine whether Pneumocystis jirovecii pneumonia prophylaxis with sulfamethoxazole-trimethoprim (SMX-TMP) is associated with an increased frequency of acute hemolytic anemia in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency versus non-G6PD-deficient controls in a pediatric oncology population. There was no statistically significant difference in change in hemoglobin or transfusion requirements after starting SMX-TMP between groups. These findings suggest no increased risk of acute hemolytic anemia with SMX-TMP administered at prophylaxis doses in patients with G6PD deficiency.

Perinatal risk factors and neurocognitive outcomes in children and adolescents with sickle cell disease.

BACKGROUND: The literature on cognitive and academic outcomes for children with sickle cell disease (SCD) who experience perinatal risk factors is limited. We aimed to evaluate if low birthweight (LBW), gestational age, and history of neonatal intensive care unit (NICU) admission were associated with neurocognitive functioning, grade retention, or receipt of early intervention or formal educational support in children with SCD. PROCEDURES: This prospective birth cohort study included 336 participants, ages 8-18, with SCD, who received cognitive testing as part of standard of care and whose caregivers completed behavioral rating scales. Multivariable generalized linear regression models were used to examine associations between perinatal risks and outcome variables, after adjusting for demographic and medical covariates. RESULTS: The prevalence of NICU admission and LBW were 12.03% and 13.50%, respectively. Lower birthweight, earlier gestational age, and NICU admission were associated with worse working memory performance and receipt of early intervention services. Lower birthweight and NICU admission were also associated with slower processing speed. History of NICU admission was associated with caregiver ratings of hyperactivity and emotional dysregulation. The effects of perinatal risk factors on neurocognitive, academic, or educational outcomes were not dependent on SCD genotype. CONCLUSIONS: History of LBW or NICU admission was associated with worse cognitive outcomes and increased use of early intervention services among children with SCD. Early identification of perinatal risk factors will help identify children who will benefit from formal developmental or neuropsychological evaluations to manage the comorbidity of SCD and perinatal risks and facilitate increased intervention.

Impact of hematopoietic cell transplantation on myocardial fibrosis in young patients with sickle cell disease.

ABSTRACT: Serial cardiovascular magnetic resonance evaluation of children and young adults with SCD who underwent hematopoietic cell transplantation showed mean ECV, representing diffuse myocardial fibrosis, decreased 3.4% from baseline to 12 months posttransplantation. This trial was registered at www.clinicaltrials.gov as #NCT04362293.

Machine learning to optimize automated RH genotyping using whole-exome sequencing data.

ABSTRACT: Rh phenotype matching reduces but does not eliminate alloimmunization in patients with sickle cell disease (SCD) due to RH genetic diversity that is not distinguishable by serological typing. RH genotype matching can potentially mitigate Rh alloimmunization but comprehensive and accessible genotyping methods are needed. We developed RHtyper as an automated algorithm to predict RH genotypes using whole-genome sequencing (WGS) data with high accuracy. Here, we adapted RHtyper for whole-exome sequencing (WES) data, which are more affordable but challenged by uneven sequencing coverage and exacerbated sequencing read misalignment, resulting in uncertain predictions for (1) RHD zygosity and hybrid alleles, (2) RHCE∗C vs. RHCE∗c alleles, (3) RHD c.1136C>T zygosity, and (4) RHCE c.48G>C zygosity. We optimized RHtyper to accurately predict RHD and RHCE genotypes using WES data by leveraging machine learning models and improved the concordance of WES with WGS predictions from 90.8% to 97.2% for RHD and 96.3% to 98.2% for RHCE among 396 patients in the Sickle Cell Clinical Research and Intervention Program. In a second validation cohort of 3030 cancer survivors (15.2% Black or African Americans) from the St. Jude Lifetime Cohort Study, the optimized RHtyper reached concordance rates between WES and WGS predications to 96.3% for RHD and 94.6% for RHCE. Machine learning improved the accuracy of RH predication using WES data. RHtyper has the potential, once implemented, to provide a precision medicine-based approach to facilitate RH genotype-matched transfusion and improve transfusion safety for patients with SCD. This study used data from clinical trials registered at ClinicalTrials.gov as #NCT02098863 and NCT00760656.

Description of a national, multi-center registry of patients with sickle cell disease and SARS-CoV-2 infection: Data from the Pediatric COVID-19 United States Registry.

Children with sickle cell disease (SCD) are at risk of complications from viral infections, including SARS-CoV-2. We present the clinical characteristics and outcomes of pediatric patients with SCD from the Pediatric COVID-19 United States Registry who developed acute COVID-19 due to SARS-CoV-2 infection (n = 259) or multisystem inflammatory syndrome in children (MIS-C; n = 4). Nearly half of hospitalized children with SCD and SARS-CoV-2 infection required supplemental oxygen, though children with SCD had fewer intensive care (ICU) admissions compared to the general pediatric and immunocompromised populations. All registry patients with both SCD and MIS-C required ICU admission. Children with SCD are at risk of severe disease with SARS-CoV-2 infection, highlighting the importance of vaccination in this vulnerable population.

Translation, transcultural adaptation, and validation of PedsQL 3.0 Sickle Cell Disease Module into Brazilian Portuguese.

INTRODUCTION: Despite the high prevalence of sickle cell disease (SCD) in Brazil, no studies have described the validation of an SCD-specific health-related quality-of-life (HRQoL) instrument in children. We validated PedsQL 3.0 Sickle Cell Disease Module (PedsQL-SCD) for Brazilian Portuguese, and cross-validated it with PedsQL 4.0 Generic Core Scale (PedsQL-GCS) in children with SCD. METHODS: PedsQL-SCD was translated and culturally adapted using forward and reverse translations. PedsQL-SCD and PedsQL-GCS were tested in children and adolescents with SCD aged 2-18 years and their caregivers. Validity was assessed using the Pearson and intraclass correlation coefficients, and reliability measured with Cronbach's alpha. RESULTS: PedsQL-SCD was validated in 206 children with SCD (median age 14 years, range: 8-18) and 201 caregivers. Among patients and caregivers, the mean total score for PedsQL-SCD was 65.7 and 64.1, respectively. The mean total score for PedsQL-GCS was 73.1 and 68.9 among patients and caregivers, respectively. The internal consistency for PedsQL-SCD and PedsQL-GCS was good; Cronbach's alpha coefficients ranged from .59-.93 to .64-.83 among patients and from .60-.95 to .65-.85 among caregivers, respectively. Most intercorrelations between PedsQL-SCD and PedsQL-GCS, for patients and caregivers, had medium to large effect sizes (range: .23-.63 and .27-.64, respectively). Pain and pain impact domains of PedsQL-SCD and physical dimension of PedsQL-GCS had the highest cross-correlation (.63 and .6 for patients; .63 and .64 for caregivers, respectively), confirming convergent construct validity. CONCLUSION: PedsQL-SCD is a valid, culturally appropriate measure to assess HRQoL in children with SCD in Brazil and is well-correlated PedsQL-GCS.

Multicomponent Strategy Improves Human Papillomavirus Vaccination Rates Among Adolescents with Sickle Cell Disease.

OBJECTIVE: To evaluate the effectiveness of a vaccine strategy bundle to increase human papillomavirus (HPV) vaccine initiation and completion in a specialty clinic setting. STUDY DESIGN: Our Hematology clinic utilized an implementation framework from October 1, 2018, to December 31, 2019, involving nurses, nursing coordinators, and clinicians in administering the HPV vaccination series to our adolescent sickle cell sample of nearly 500 patients. The bundle included education for staff on the need for HPV vaccine administration, provider incentives, vaccines offered to patients in SCD clinics, and verification of patients' charts of vaccine completion. RESULTS: Following the implementation of the bundle, the cumulative incidence of HPV vaccination initiation and completion improved from 28% to 46% and 7% to 49%, respectively. Both rates remained higher postimplementation as well. HPV vaccination series completion was associated with a decreased distance to the health care facility, lower state deprivation rank, and increased hospitalizations. CONCLUSION: Our clinic's implementation strategy successfully improved vaccine completion rates among adolescents with sickle cell disease (SCD) while continuing to educate staff, patients, and families on the importance of cancer prevention among people living with SCD.

Evaluation of Capacity for Implementation of Pediatric-to-Adult Care Transition for Sickle Cell Disease in Brazil

Implementation of HCT programs is a high priority in Brazil, given the growing survival rates for children with SCD. Our data highlights a well-connected community of healthcare workers, but also reveals that the current level of HCT activities for SCD in Brazil is low. This underscores the urgent need for transition intervention. The key facilitators for successful HCT implementation in Brazil are strong leadership and a motivated workforce. However, community participation and finances are weak points that require implementation strategies during program implementation. Compared to the US, both Brazilian institutions scored significantly lower on all components needed for transition, emphasizing the need for intervention. This project is the first to evaluate the readiness for HCT implementation in a low- and middle-income country. Designing a context-specific HCT program that suits low-resource settings will improve outcomes for individuals with SCD in the country. (AU)

Examining the influence of pain and fatigue on neurocognitive functioning in adolescents and young adults with sickle cell disease.

Pain and fatigue are among the most common and impactful complications of sickle cell disease (SCD). Individuals with SCD are also more likely to have neurocognitive deficits. Previous studies have suggested that pain and fatigue might influence neurocognitive functioning in patients with SCD. However, these studies are limited by small sample sizes and inadequate measurement of cognitive performance. The present study aimed to investigate the relationship between pain and fatigue with neurocognitive functioning using performance-based measures of neurocognition. Pain and fatigue were not associated with neurocognitive performance. Implications and directions for future research are discussed.

CRISPR-Cas9 Editing of the HBG1 and HBG2 Promoters to Treat Sickle Cell Disease.

BACKGROUND: Sickle cell disease is caused by a defect in the ß-globin subunit of adult hemoglobin. Sickle hemoglobin polymerizes under hypoxic conditions, producing deformed red cells that hemolyze and cause vaso-occlusion that results in progressive organ damage and early death. Elevated fetal hemoglobin levels in red cells protect against complications of sickle cell disease. OTQ923, a clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9-edited CD34+ hematopoietic stem- and progenitor-cell (HSPC) product, has a targeted disruption of the HBG1 and HBG2 (γ-globin) gene promoters that increases fetal hemoglobin expression in red-cell progeny. METHODS: We performed a tiling CRISPR-Cas9 screen of the HBG1 and HBG2 promoters by electroporating CD34+ cells obtained from healthy donors with Cas9 complexed with one of 72 guide RNAs, and we assessed the fraction of fetal hemoglobin-immunostaining erythroblasts (F cells) in erythroid-differentiated progeny. The gRNA resulting in the highest level of F cells (gRNA-68) was selected for clinical development. We enrolled participants with severe sickle cell disease in a multicenter, phase 1-2 clinical study to assess the safety and adverse-effect profile of OTQ923. RESULTS: In preclinical experiments, CD34+ HSPCs (obtained from healthy donors and persons with sickle cell disease) edited with CRISPR-Cas9 and gRNA-68 had sustained on-target editing with no off-target mutations and produced high levels of fetal hemoglobin after in vitro differentiation or xenotransplantation into immunodeficient mice. In the study, three participants received autologous OTQ923 after myeloablative conditioning and were followed for 6 to 18 months. At the end of the follow-up period, all the participants had engraftment and stable induction of fetal hemoglobin (fetal hemoglobin as a percentage of total hemoglobin, 19.0 to 26.8%), with fetal hemoglobin broadly distributed in red cells (F cells as a percentage of red cells, 69.7 to 87.8%). Manifestations of sickle cell disease decreased during the follow-up period. CONCLUSIONS: CRISPR-Cas9 disruption of the HBG1 and HBG2 gene promoters was an effective strategy for induction of fetal hemoglobin. Infusion of autologous OTQ923 into three participants with severe sickle cell disease resulted in sustained induction of red-cell fetal hemoglobin and clinical improvement in disease severity. (Funded by Novartis Pharmaceuticals; ClinicalTrials.gov number, NCT04443907.).

Infertility and treatment-seeking practices among females and males with sickle cell disease in the Sickle Cell Disease Implementation Consortium registry.

OBJECTIVE: To describe the prevalence of infertility and infertility treatment seeking among people enrolled in the Sickle Cell Disease Implementation Consortium (SCDIC) registry and identify sociodemographic and clinical correlates of infertility. DESIGN: Cross-sectional. PARTICIPANTS: The study population included 2108 women and men (≥18 years of age) enrolled in the SCDIC registry who completed the fertility questionnaire. RESULTS: All participants who completed the infertility-specific questions were included in the analysis (1224 females; 884 males). Of these, 16.9% of males and 23.7% of females reported infertility, in contrast to rates in the general population (12% of males; 11% of females). Only 22.8% of this subgroup had sought a fertility consultation; of these, 41% received infertility testing and 58% received advice, yet only a few received specific treatment: ovulation medication (19.1%), fallopian tubal surgery (4.8%), other female treatment (17.5%), varicocelectomy (8.1%), or other male treatment (10.8%). Increasing age, employment status, and interaction between gender and single marital status are associated with reported infertility. We did not observe differences between groups relative to sickle cell disease (SCD) genotype, a broad category of self-reported hydroxyurea use any time during life, type of medical insurance, income, or education. CONCLUSION: To our knowledge, this is the first study to examine self-reported identification of and treatment for infertility among a large sample of people with SCD. These findings suggest that (a) infertility occurs at a higher rate, but fertility care treatment seeking is less frequent than in the general public; and (b) sociodemographic and clinical differences between individuals who report experiencing infertility and those who do not did not emerge in this study.

Attitudes toward COVID-19 vaccine among pediatric patients with sickle cell disease and their caregivers.

OBJECTIVE: To evaluate attitudes toward vaccination and vaccine uptake regarding coronavirus disease 2019 (COVID-19) among pediatric patients with sickle cell disease (SCD) and their caregivers. PROCEDURE: Adolescent patients and caregivers of children with SCD were surveyed during routine clinic visits; we then conducted a logistic regression analysis to understand differences in vaccine status, while qualitative responses were coded thematically. RESULTS: Among respondents, the overall vaccination rate among adolescents and caregivers was 49% and 52%, respectively. Among the unvaccinated, 60% and 68% of adolescents and caregivers, respectively, preferred to remain unvaccinated, most commonly due to lack of perceived personal benefit from vaccination or mistrust in the vaccine. Multivariate logistic regression analysis showed that child's age (odds ratio [OR] = 1.1, 95% confidence interval [CI]: 1.0-1.2, p < .01) and caregiver education (measured by the Economic Hardship Index [EHI] score, OR = 0.76, 95% CI: 0.74-0.78, p < .05) were independent predictors of getting vaccinated. CONCLUSION: Despite the increased risk of severe illness due to COVID-19 in patients with SCD, vaccine hesitancy remains high in this population of families whose children have SCD. Fortunately, the reasons cited for deferring vaccination among those who are unvaccinated were largely due to barriers that may be overcome with quality communication around the utility of the vaccine and information about vaccine safety.

Health literacy correlates with abbreviated full-scale IQ in adolescent and young adults with sickle cell disease.

INTRODUCTION: Sickle cell disease (SCD) is a chronic condition with progressive neurocognitive deficits. Health literacy (HL) is essential during adolescence and young adulthood, as the transition to adult care requires healthcare decisions. HL is known to be low in SCD; however, relation between general cognitive ability and HL has not been investigated. METHODS: This cross-sectional study included adolescent and yound adults (AYAs) with SCD from two institutions. Logistic regression measured the association between HL, measured by the Newest Vital Sign tool, and general cognitive ability, measured with abbreviated full-scale intelligence quotient (FSIQ) on the Wechsler Abbreviated Scale of Intelligence. RESULTS: Our cohort contained 93 participants at two sites: 47 (51%) at Memphis, TN and 46 (49%) at St. Louis, MO, ranging from ages 15-45 years (mean = 21 years) and with a majority (70%) possessing a high school education or greater. Only 40/93 participants (43%) had adequate HL. Lower abbreviated FSIQ (p < .0001) and younger age at assessment (p = .0003) were associated with inadequate HL. For every standard score point increase in abbreviated FSIQ, the odds of having adequate HL compared to limited or possibly limited HL increase by 1.142 (95% confidence interval [CI]: 1.019-1.322) and 1.116 (95% CI: 1.045-1.209), respectively, after adjusting for age, institution, income, and educational attainment. CONCLUSIONS: Understanding and addressing HL is imperative in improving self-management and health outcomes. Among AYA with SCD, low HL was prevalent and influenced by abbreviated FSIQ. Routine screening for neurocognitive deficits and HL should be performed to guide development of interventions to adapt to the HL of AYA with SCD.

Gene therapy in sickle cell disease: Attitudes and informational needs of patients and caregivers.

BACKGROUND: Sickle cell disease (SCD) is an inherited blood disorder that results in serious morbidity and early mortality. Novel therapies for SCD, most notably genetic therapies (GTs) and HLA-mismatched donor hematopoietic cell transplantation, are in clinical trials. While potentially curative, these interventions are some of the most intensive treatments for SCD and are associated with serious and life-altering side effects, which may manifest several years after treatment. Little is known about knowledge, beliefs, and attitudes of individuals with SCD, or their caregivers, toward existing and these emerging therapies. METHODS: Patients with SCD at least 13 years of age (n = 66) and caregivers (n = 38) were surveyed about knowledge, attitudes, and beliefs surrounding treatments for SCD. RESULTS: Only 4.8% felt "extremely knowledgeable" about GT for SCD while the majority (63.4%) reported little knowledge. Overall, health literacy was low among respondents. Most respondents had a neutral attitude regarding the safety of GT for SCD, and whether it was a good treatment for the disorder (56.7% and 58.6%, respectively). Only a few respondents endorsed the idea that GT was "unsafe" or "not a good treatment" (5.8% and 4.8%, respectively). There was an association between increasing knowledge about GT and agreement that it is safe (p = .012) and a good treatment for SCD (p = .031). CONCLUSIONS: Given that very few patients with SCD feel knowledgeable about GT and a majority have neutral feelings about the safety and utility of this new approach, culturally appropriate patient-centered education is urgently needed as these treatments get regulatory approval and proceed to the clinic.

Social determinants of neurocognitive and academic performance in sickle cell disease.

BACKGROUND: Sickle cell disease (SCD) is associated with poor neurocognitive outcomes due to biomedical and psychosocial factors. The aims of this study were to investigate associations between household and neighborhood socioeconomic status (SES) with cognitive and academic outcomes in SCD and to determine if these relationships were modified by sickle genotype, fetal hemoglobin, or age. PROCEDURE: We prospectively recruited patients to complete a battery of neurocognitive and academic measures. Household SES was measured using the Barratt Simplified Measure of Social Status, a composite index of parent education and occupation. The Social Vulnerability Index was used to classify individuals based on social vulnerabilities at the neighborhood level. RESULTS: Overall, 299 patients between the ages of 4 and 18 (mean = 11.4, standard deviation = 4.3) years diagnosed with SCD (57% SS/SB0 -thalassemia) completed testing. Stepwise multivariate models demonstrated that patients with low social vulnerability (i.e., high SES) at the neighborhood level displayed intelligence and math scores that were 4.70 and 7.64 points higher than those living in areas with moderate social vulnerability, respectively (p < .05). Reading performance did not differ based on neighborhood SES; however, the effect of neighborhood SES was dependent on age, such that older participants living in neighborhoods with moderate or high levels of social vulnerability displayed poorer reading scores than those with low social vulnerability (p < .05). CONCLUSIONS: This study identified patients with SCD at higher risk of poor academic performance based on SES. Interventions addressing academic difficulties should be offered to all children with SCD, but should be emergently offered to this subpopulation.

Consensus definition of essential, optimal, and suggested components of a pediatric sickle cell disease center.

Sickle cell disease (SCD) requires coordinated, specialized medical care for optimal outcomes. There are no United States (US) guidelines that define a pediatric comprehensive SCD program. We report a modified Delphi consensus-seeking process to determine essential, optimal, and suggested elements of a comprehensive pediatric SCD center. Nineteen pediatric SCD specialists participated from the US. Consensus was predefined as 2/3 agreement on each element's categorization. Twenty-six elements were considered essential (required for guideline-based SCD care), 10 were optimal (recommended but not required), and five were suggested. This work lays the foundation for a formal recognition process of pediatric comprehensive SCD centers.

Sickle cell disease and social determinants of health: A scoping review.

Social determinants of health (SDoH) may impact outcomes in sickle cell disease (SCD). We conducted a comprehensive literature review of five electronic databases to elucidate the relationship between SDoH and SCD, and identify gaps in the literature. Our search yielded 59 articles, which we organized into five SDoH areas: Neighborhood and Built Environment, Health and Healthcare, Social and Community Context, Education, and Economic Stability. We found that social determinants, such as access to healthcare, were inconsistently evaluated. Improved recognition and understanding of SDoH should enhance the development of programs that directly address its detrimental effects on patients with SCD.

Neurocognitive functioning in children with sickle cell anemia and history of abnormal transcranial doppler ultrasonography.

BACKGROUND: Transcranial doppler (TCD) ultrasonography can be used to identify stroke risk in children with sickle cell anemia. Previous studies have reported mixed findings on neurocognitive outcomes in children with elevated TCD. This study examined associations between TCD velocity and neurocognitive outcomes in children and adolescents without prior history of stroke. PROCEDURE: Participants were selected from the Sickle Cell Clinical Research Intervention Program cohort. The highest recorded mean maximum TCD velocity was selected for analysis, along with participant's most recent data from serial neurocognitive surveillance. RESULTS: A total of 200 children with sickle cell anemia completed neurocognitive testing (109 males, 91 females; mean age 12.7 years [SD = 3.56]). Most participants were prescribed hydroxyurea (72%) at the time of neurocognitive testing and nearly 16% had a history of chronic transfusions prior to neurocognitive evaluation. Mean age at time of highest TCD value was 6.6 years (SD = 2.5) and 13.5% of screenings were abnormal (≥200 cm/s). Mean interval between TCD and most recent neurocognitive evaluation was 6.1 years (±3.5). There were no significant differences in the interval between TCD and neurocognitive testing across normal, conditional, and abnormal groups. Maximum TCD velocity was not significantly associated with neurocognitive outcomes in multivariate models. CONCLUSIONS: History of elevated TCD in the absence of overt stroke should not be considered a risk factor for poor neurocognitive outcomes in children and adolescents with sickle cell anemia on modern disease-modifying therapy.

Optimizing haematopoietic stem and progenitor cell apheresis collection from plerixafor-mobilized patients with sickle cell disease.

We adjusted haematopoietic stem and progenitor cell (HSPC) apheresis collection from patients with sickle cell disease (SCD) by targeting deep buffy coat collection using medium or low collection preference (CP), and by increasing anticoagulant-citrate-dextrose-solution A dosage. In 43 HSPC collections from plerixafor-mobilized adult patients with SCD, we increased the collection efficiency to 35.79% using medium CP and 82.23% using low CP. Deep buffy coat collection increased red blood cell contamination of the HSPC product, the product haematocrit was 4.7% with medium CP and 6.4% with low CP. These adjustments were well-tolerated and allowed efficient HSPC collection from SCD patients.

Enuresis and Hyperfiltration in Children With Sickle Cell Disease.

Nocturnal enuresis is a common symptom in children with sickle cell disease (SCD). Risk factors for development of enuresis are currently unknown. An early manifestation of SCD-associated kidney damage is glomerular hyperfiltration. We test the hypothesis that in a pediatric SCD cohort, individuals with hyperfiltration are more likely to have nocturnal enuresis when compared to children without hyperfiltration. To assess the relationship between nocturnal enuresis and hyperfiltration, we retrospectively evaluated children with SCD enrolled in the Evaluation of Nocturnal Enuresis and Barriers to Treatment among Pediatric Patients with SCD study and prospectively identified children who reported nocturnal enuresis and were enrolled in the longitudinal cohort study Sickle Cell Clinical Research and Intervention Program. Nocturnal enuresis occurred in 46.5% of Pediatric Patients with Sickle Cell Disease participants and was more frequent in participants with HbSS/HbSß 0 thalassemia and in male participants. We did not identify an association between hyperfiltration from 3 to 5 years of age with the later development of enuresis. Severe SCD genotypes and male sex were associated with nocturnal enuresis after age 5 years. We could not identify additional renal or hematologic predictors associated with the diagnosis of nocturnal enuresis. Future studies should incorporate nonrenal risk factors into studies that predict development of enuresis.