Sickle Cell Disease

Accuracy of online medical information: the case of social media in sickle cell disease

The medical needs of individuals with sickle cell disease (SCD) are complex. Patients with SCD experience complications such as recurrent pain episodes and increased hospitalizations. Over 70% of AYA and their parents seek medical information from the Internet; 83% inquire on sites that have interactive/social features, such as Facebook or Twitter, yet accuracy remains unclear. Our objective was to assess the accuracy of the SCD-information posted on social media. We hypothesized that most of the posted information is inaccurate. We coded one month of threads from two common SCD Facebook groups (Sickle Cell Warriors Unity and Sickle Cell Anemia) to identify the purpose of each post and the accuracy of medical information posted. Amongst both social media sites, there were 487 posts. Most of the posts were directed toward socializations (n = 311, 63.8%), while other posts mainly focused mainly on SCD and its management (n = 173, 35.5%). When looking at the medical posts, 44.9% were accurate, whereas 55.1% of the posts included inaccurate information. We found that less than half of the medical information posted on interactive social media is inaccurate. Our findings raise potentially serious implications for individuals with SCD and/or their caregivers who may rely on social media to gather more information about their or their child's disease. Our data highlight the importance of health care providers encouraging patients and parents to ask any questions they may have about SCD, given they may consult social media and Internet site that provide inaccurate information.

Mortality Rates and autopsy findings in fat embolism syndrome complicating sickle cell disease

Fat embolism syndrome is a rare but underdiagnosed complication of sickle cell disease associated with high morbidity and mortality. It affects predominantly patients with a previously mild course of their illness and those of non-SS genotypes while there is possibly an association with infection with human parvovirus B19 (HPV B19). Here, we present the mortality rates and autopsy findings of all reported cases to date. A systematic review has revealed 99 published cases in the world literature with a mortality rate of 46%. Mortality varied greatly according to the time of reported cases with no survivors in the 1940s, 1950s or 1960s and no deaths since 2020. 35% of cases had previously undiagnosed sickle cell disease and the latter was only identified at autopsy after developing fat embolism with a fatal outcome. 20% of cases reported after 1986 tested positive for HPV B19 with an associated mortality of 63% whereas in cases that have not documented HPV B19 infection the mortality was 32%. The organs most often staining positive for fat were the kidneys, lungs, brain and heart whereas ectopic haematopoietic tissue was found in 45% of the examined lung specimens.

Diaphragm excursion correlates with performance and ventilation on the 6-min walk test in children with sickle cell disease

INTRODUCTION

Diaphragm function may be impaired in children with sickle cell disease (SCD). We hypothesized that diaphragm function is related to performance and ventilation on the 6-min walk test (6MWT).

METHODS

Respiratory muscle testing, diaphragm ultrasonography, and the 6MWT with portable gas analysis were performed on children with SCD and age- and sex-matched controls.

RESULTS

Fourteen children with SCD were enrolled. Comparisons were made between nine children with SCD (9.89  ± $\pm $  2.93 years) and nine controls (10.33  ± $\pm $  2.35 years). Diaphragm thickness at total lung capacity, thickening fraction, and excursion time during quiet breaths and deep breaths (DB), all normalized by forced vital capacity, were greater in children with SCD ( p < $p\lt $ 0.05 for all). 6MWT distance was shorter in children with SCD (450.87  ± $\pm $  74.2 m vs. 579.22 ± $\pm $ 72.46 m, p = $p=$ 0.01). Tidal volume ( V T ${V}_{T}$ ), minute ventilation ( V ˙ E ${\dot{V}}_{E}$ ), and oxygen consumption ( V ˙ O 2 ${\dot{V}}_{{O}_{2}}$ ) were also lower ( p < $p\lt $ 0.05 for all). DB excursion correlated positively with 6MWT distance ( r = $r=$ 0.648, p = $p=$ 0.023) and negatively with rate of perceived exertion (RPE) ( r = $r=$ -0.759, p = $p=$ 0.003). RPE correlated negatively with distance ( r = $r=$ -0.680, p = $p=$ 0.015). DB excursion time correlated positively with distance ( r = $r=$ 0.611, p = $p=$ 0.035), V T ${V}_{T}$ ( r = $r=$ 0.770, p = $p=$ 0.009), V ˙ E ${\dot{V}}_{E}$ ( r = $r=$ 0.736, p = $p=$ 0.015), and V ˙ O 2 ${\dot{V}}_{{O}_{2}}$ ( r = $r=$ 0.751, p = $p=$ 0.012).

CONCLUSIONS

Increased diaphragm excursion may be a strategy used to relieve air hunger while longer excursion time may reflect compensations to increase lung recruitment. Further studies are needed to better understand how these mechanisms affect exercise tolerance in children with SCD.

What is hemoglobin, albumin, lymphocyte, platelet (HALP) score? A comprehensive literature review of HALP's prognostic ability in different cancer types

Since its inception, the Hemoglobin, Albumin, Lymphocyte, Platelet Score (HALP) has gained attention as a new prognostic biomarker to predict several clinical outcomes in a multitude of cancers. In our review, we searched PubMed for articles between the first paper on HALP in 2015 through September 2022, yielding 32 studies in total that evaluated HALP's association with various cancers, including Gastric, Colorectal, Bladder, Prostate, Kidney, Esophageal, Pharyngeal, Lung, Breast, and Cervical cancers, among others. This review highlights the collective association HALP has with demographic factors such as age and sex in addition to TNM staging, grade, and tumor size. Furthermore, this review summarizes HALP's prognostic ability to predict overall survival, progression-free survival, recurrence-free survival, among other outcomes. In some studies, HALP has also been able to predict response to immunotherapy and chemotherapy. This review article also aims to serve as a comprehensive and encyclopedic report on the literature that has evaluated HALP as a biomarker in various cancers, highlighting the heterogeneity surrounding HALP's utilization. Because HALP requires only a complete blood count and albumin - already routinely collected for cancer patients - HALP shows potential as a cost-effective biomarker to aid clinicians in improving outcomes for immuno-nutritionally deficient patients.

Lifetime medical costs attributable to sickle cell disease among nonelderly individuals with commercial insurance

Sickle cell disease (SCD) is a severe monogenic disease associated with high morbidity, mortality, and a disproportionate burden on Black and Hispanic communities. Our objective was to estimate the total healthcare costs and out-of-pocket (OOP) costs attributable to SCD among commercially insured individuals over their nonelderly lifetimes (0 to 64 years of age). We constructed a retrospective cohort of individuals with diagnosed SCD using Truven Health Marketscan commercial claims data from 2007 through 2018, compared with matched control subjects from the Medical Expenditure Panel Survey. We estimated Kaplan-Meier sample average costs using previously reported survival curves for SCD and control subjects. Individuals with SCD (20 891) and control subjects (33 588) were included in our analysis. The SCD sample had a mean age of 25.7 (standard deviation, 17.4) years; 58.0% were female. Survival-adjusted costs of SCD peaked at age 13 to 24 years and declined at older ages. There was no significant difference in total medical costs or OOP costs between the sexes. SCD-attributable costs over 0 to 64 years of age were estimated to be $1.6 million (95% confidence interval [CI], $1.3M-$1.9M) and $1.7 million (95% CI, $1.4M-$2.1M) for females and males with SCD, respectively. The corresponding OOP estimates were $42 395 (95% CI, $34 756-$50 033) for females and $45 091 (95% CI, $36 491-$53 691) for males. These represent a 907% and 285% increase in total medical and OOP costs over control subjects, respectively. Although limited to the commercially insured population, these results indicate that the direct economic burden of SCD is substantial and peaks at younger ages, suggesting the need for curative and new medical therapies.

Atomic force microscopy reveals involvement of the cell envelope in biomechanical properties of sickle erythrocytes

BACKGROUND

Intracellular hemoglobin polymerization has been supposed to be the major determinant for the elevated rigidity/stiffness of sickle erythrocytes from sickle cell anemia (SCA) patients. However, the contribution of the cell envelope remains unclear.

RESULTS

In this study, using atomic force microscopy (AFM), we compared the normal and sickled erythrocyte surfaces for stiffness and topography. AFM detected that sickle cells had a rougher surface and were stiffer than normal erythrocytes and that sickle cell ghosts had a rougher surface (for both outer and inner surfaces) and were thicker than normal ghosts, the latter implying a higher membrane-associated hemoglobin content/layer in the sickle cell envelope. Compared to healthy subjects, the SCA patients had lower plasma lipoprotein levels. AFM further revealed that a mild concentration of methyl-β-cyclodextrin (MβCD, a putative cholesterol-depleting reagent) could induce an increase in roughness of erythrocytes/ghosts and a decrease in thickness of ghosts for both normal and sickle cells, implying that MβCD can alter the cell envelope from outside (cholesterol in the plasma membrane) to inside (membrane-associated hemoglobin). More importantly, MβCD also caused a more significant decrease in stiffness of sickle cells than that of normal erythrocytes.

CONCLUSIONS

The data reveal that besides the cytosolic hemoglobin fibers, the cell envelope containing the membrane-associated hemoglobin also is involved in the biomechanical properties (e.g., stiffness and shape maintenance) of sickle erythrocytes.

A Review of CRISPR Cas9 for SCA: Treatment Strategies and Could Target β-globin Gene and BCL11A Gene using CRISPR Cas9 Prevent the Patient from Sickle Cell Anemia?

BACKGROUND: Sickle cell anemia is a hereditary globin chain condition that leads to hemolysis and persistent organ damage. Chronic hemolytic anemia, severe acute and chronic pain, and end-organ destruction occur throughout the lifespan of sickle cell anemia. SCD is associated with a higher risk of mortality. Genome editing with CRISPR-associated regularly interspersed short palindromic repeats (CRISPR/Cas9) have therapeutic potential for sickle cell anemia thala. AIM: This research aimed to see if using CRISPR/Cas9 to target β-globin gene is an effective therapeutic and if it has a long-term effect on Sickle Cell Anemia. METHODS: The method used in this study summarizes the article by looking for keywords that have been determined in the title and abstract. The authors used official guidelines from Science Direct, PubMed, Google Scholar, and Journal Molecular Biology to select full-text articles published within the last decade, prioritizing searches within the past 10 years. RESULTS: CRISPR/Cas9-mediated genome editing in clinical trials contributes to α-globin gene deletion correcting β-thalassemia through balanced α- and β-globin ratios and inhibiting disease progression. CONCLUSION: HBB and BCL11A targeting by CRISPR/Cas9 deletion effectively inactivate BCL11A, a repressor of fetal hemoglobin production. However, further research is needed to determine its side effects and safety.

Contemporary Management and Prevention of Vaso-Occlusive Crises (VOCs) in Adults With Sickle Cell Disease

Sickle cell disease (SCD) is a hematological disorder that primarily affects individuals of African descent from sub-Saharan Africa and along the mediterranean. The main complications leading to hospitalizations include vaso-occlusive crises (VOCs) and acute chest syndrome (ACS). Therefore, the main objective of this paper was to identify and evaluate evidence-based management and prevention of VOCs in patients with SCD. A literature search of PubMed, Medline Cochrane and Google Scholar database (January 1985 to April 2020) was performed using the following search terms "vaso-occlusive crises", "sickle cell disease", "hydroxyurea", "L-glutamine", "voxelotor", "crizanlizumab", "treatment" and "prevention" as well as a combination of these terms. All English-language interventional studies assessing the efficacy and safety of VOC outcomes were evaluated. Literature was excluded if published in a language other than English or if it was a review article. A total of 69 articles were identified and there were 7 articles that met the search criteria. Majority of the studies focused on mean and median annual rates of VOCs as primary outcomes while median time to first sickle cell crises, median rates of hospitalizations etc were evaluated as secondary outcomes. After reviewing the literature, many patients with VOCs will still benefit from hydroxyurea therapy since long term efficacy data and cost is still a concern for the newer agents including L-glutamine, voxelotor and crizanlizumab. Other factors such as cost or compliance may also be taken into consideration when making recommendations for therapy.

Sickle cell disease in children: an update of the evidence in low- and middle-income settings

Sickle cell disease (SCD), one of the most common monogenetic diseases in the world, is associated with multisystemic complications that begin in childhood. Most of the babies homozygous for the sickle haemoglobin gene are born in sub-Saharan Africa. Over the years, progress has been made with early diagnosis through newborn screening, penicillin prophylaxis, pneumococcal immunisation, transcranial Doppler (TCD) screening, hydroxyurea therapy and chronic blood transfusions with remarkably improved survival and quality of life of children with SCD. However, wide disparities in outcomes exist between high-income countries (HICs) where over 90% survive to adulthood, and low-income and middle-income countries (LMICs) where less than half achieve that milestone. Even in HICs, racial inequities pose barriers to accessing specialised care and receiving treatment for acute pain episodes. Better understanding of SCD pathophysiology is being exploited to develop new disease-modifying drugs and gene therapy approaches to further improve outcomes. Bone marrow transplantation is established as a curative treatment for SCD, but it is largely unavailable in LMICs. To bridge the disparity and inequity gaps, innovative approaches are needed in LMICs. Validated and more affordable, easy-to-use point-of-care tests offer opportunities to link early diagnosis with immunisation programmes and healthcare encounters. Widespread use of hydroxyurea therapy-a relatively affordable and effective disease-modifying drug-in LMICs would help improve survival and quality of life. Integration of SCD treatment into primary care linked to district level/provincial hospitals that are supported with evidence-based guidelines will help extend needed interventions to many more patients living in LMICs.

Effects of hydroxyurea on skeletal muscle energetics and force production in a sickle cell disease murine model

Hydroxyurea (HU) is commonly used as a treatment for patients with sickle cell disease (SCD) to enhance fetal hemoglobin production. This increased production is expected to reduce anemia (which depresses oxygen transport) and abnormal Hb content alleviating clinical symptoms such as vaso-occlusive crisis and acute chest syndrome. The effects of HU on skeletal muscle bioenergetics in vivo are still unknown. Due to the beneficial effects of HU upon oxygen delivery, improved skeletal muscle energetics and function in response to a HU treatment have been hypothesized. Muscle energetics and function were analyzed during a standardized rest-exercise-recovery protocol, using ³¹P-magnetic resonance spectroscopy in Townes SCD mice. Measurements were performed in three groups of mice: one group of 2-mo-old mice (SCD_2m, n = 8), another one of 4-mo-old mice (SCD_4m, n = 8), and a last group of 4-mo-old mice that have been treated from 2 mo of age with HU at 50 mg/kg/day (SCD_4m-HU, n = 8). As compared with SCD_2m mice, SCD_4m mice were heavier and displayed a lower acidosis. As lower specific forces were developed by SCD_4m compared with SCD_2m, greater force-normalized phosphocreatine consumption and oxidative and nonoxidative costs of contraction were also reported. HU-treated mice (SCD_4m-HU) displayed a significantly higher specific force production as compared with untreated mice (SCD_4m), whereas muscle energetics was unchanged. Overall, our results support a beneficial effect of HU on muscle function.NEW & NOTEWORTHY Our results highlighted that force production decreases between 2 and 4 mo of age in SCD mice thereby indicating a decrease of muscle function during this period. Of interest, HU treatment seemed to blunt the observed age effect given that SCD_4m-HU mice displayed a higher specific force production as compared with SCD_4m mice. In that respect, HU treatment would help to maintain a higher capacity of force production during aging in SCD.

Presentations and outcomes among sickle cell disease patients with COVID-19 at a large southern healthcare system

OBJECTIVES

Compared with the general population, patients with sickle cell disease (SCD) typically have substantially reduced life expectancies. It is unclear whether SCD patients who acquire COVID-19 have higher rates of complications and mortality than the general population. We sought to elucidate COVID-19 presentation and outcomes in patients with SCD.

METHODS

Using retrospective chart review, we evaluated demographic characteristics, presenting symptoms, chest imaging findings, blood transfusion requirements, need for mechanical ventilation or pressor support, medication administration (including remdesivir and dexamethasone), and survival among individuals with SCD hospitalized with COVID-19 from March 2020 to December 2021.

RESULTS

Among 72 SCD patients, increased pain was the most common presenting symptom followed by cough, fever, and dyspnea. Thirty-seven (44%) received simple transfusion and 14 (17%) underwent exchange transfusion. Lung imaging findings suggestive of COVID-19 were observed in 27 (37%) patients; 21 (29%) patients were treated with remdesivir and 26 (35%) received dexamethasone. Three patients (4%) required mechanical ventilation and pressor support; all three died from COVID complications.

CONCLUSIONS

Pain is the most common presenting symptom in SCD patients with COVID-19. We observed a mortality rate higher than that among the general population among patients who required mechanical ventilation and pressor support.

Caregivers' Perspective on the Psychological Burden of Living with Children Affected by Sickle Cell Disease in Kinshasa, the Democratic Republic of Congo

There is limited information on knowledge, perceptions, and management of sickle cell disease (SCD) in Africa in general and in the Democratic Republic of the Congo (DRC) in particular. This study explored knowledge, perceptions, and burden of 26 parents/caregivers of children with SCD in three selected hospitals in Kinshasa, DRC. We conducted a focus group with in-depth interviews with parents/caregivers of children affected with SCD. Four themes were discussed, including knowledge and perceptions, diagnosis and management, society's perceptions, and the psychosocial burden and the quality of life of the family affected by SCD. The majority of participants/caregivers felt that society, in general, had negative perceptions of, attitudes toward, and knowledge about SCD. They reported that children with sickle cell are often marginalized, ignored, and excluded from society or school. They face a number of challenges related to care, management, financial difficulties, and a lack of psychological support. The results suggest the need to promote measures and strategies to improve knowledge and management of SCD in Kinshasa, DRC.

Patient-Reported Experiences in Voxelotor-Treated Children and Adults with Sickle Cell Disease: A Semistructured Interview Study

Objective

Voxelotor is a first-in-class sickle hemoglobin-polymerization inhibitor that was approved in 2019 by the US Food and Drug Administration for treatment of patients with sickle cell disease (SCD) aged ≥12 years; in 2021, the approval was extended to children with SCD aged 4 to 11 years. Additionally, both the Ministry of Health and Prevention for the United Arab Emirates and the European Commission granted marketing authorization for voxelotor in September 2021 and February 2022, respectively, for treatment of SCD in adults and pediatric patients aged ≥12 years. Thus, additional information on the patient experience with voxelotor would be useful for patients, caregivers, and healthcare professionals alike. The purpose of this study was to conduct semistructured interviews in an effort to understand the experiences and perspectives of voxelotor-treated patients with SCD.

Methods

One-time semistructured interviews with adults, adolescents, and children with SCD and their primary caregivers were conducted in the United States. Twenty-three adults and adolescents were recruited across 4 clinical sites, and 10 children-caregiver dyads were recruited from a single site. The interview was designed to elicit patient perspectives on symptomatic changes with voxelotor and the impact of treatment on patients' perceived health-related quality of life. Individual interview transcripts were analyzed using a thematic analytic approach, and concept saturation was assessed in both cohorts.

Results

Most patients reported improvements in their SCD symptoms with voxelotor treatment, specifically regarding pain crises, jaundice, and fatigue. Almost all patients experienced improvements in self-reported health-related quality of life with voxelotor treatment.

Conclusions

This study provides patient and caregiver perspectives on the symptomatic benefits of voxelotor treatment. These findings not only highlight the benefits of voxelotor treatment in improving symptoms and increasing health-related quality of life across the entire SCD population but also can inform further research on SCD-specific patient-reported outcomes.

Diverse Approaches to Gene Therapy of Sickle Cell Disease

Sickle cell disease (SCD) results from a single base pair change in the sixth codon of the β-globin chain of hemoglobin, which promotes aggregation of deoxyhemoglobin, increasing rigidity of red blood cells and causing vaso-occlusive and hemolytic complications. Allogeneic transplant of hematopoietic stem cells (HSCs) can eliminate SCD manifestations but is limited by absence of well-matched donors and immune complications. Gene therapy with transplantation of autologous HSCs that are gene-modified may provide similar benefits without the immune complications. Much progress has been made, and patients are realizing significant clinical improvements in multiple trials using different approaches with lentiviral vector-mediated gene addition to inhibit hemoglobin aggregation. Gene editing approaches are under development to provide additional therapeutic opportunities. Gene therapy for SCD has advanced from an attractive concept to clinical reality.

[Splenic dysfunction in sickle cell disease: An update]

The spleen filters blood cells and contributes to the immune defense. The red pulp clears the blood from altered red blood cells via its unique microcirculatory network ; while the white pulp is a secondary lymphoid organ, directly connected to the bloodstream, whose specificity is the defense against encapsulated bacteria through the production of "natural" IgM in the marginal zone. Various health conditions can cause acquired impairment of the splenic function (or hyposplenism) directly and/or through therapeutic splenectomy. Hypo/asplenia is complicated by an increased susceptibility to encapsulated germ infections, but an increased risk of thrombosis and pulmonary hypertension has also been reported after surgical splenectomy. Homozygous sickle cell disease is the most common disease associated with functional asplenia. The latter appears early in childhood likely through repeated ischemic alterations caused by the sickling of red blood cells. In addition, specific complications such as hypersplenism and acute splenic sequestration can occur and may be life-threatening. We provide here an update on the role and physiology of the spleen, which will allow a better understanding of the pathophysiology of spleen damage and its consequences in sickle cell disease.

The Burden of Sickle Cell Disease in Saudi Arabia: A Single-Institution Large Retrospective Study

Purpose

Sickle cell disease (SCD) is a significant burden for patients and healthcare systems due to multiple factors, including high readmission rates. This study aimed to determine the general characteristics, etiology of admissions, annual admission rate, length of stay, and readmission rate of patients with SCD.

Patients and Methods

This retrospective observational study included all adult patients with SCD admitted to the General Internal Medicine (GIM) unit between 2016 and 2021.

Results

There were 160 patients (mean age, 31.08 ± 9.06 years; 51.25% female) with SCD included in this study. Most originated from southern Saudi Arabia (45.62%). The average annual number of emergency department (ED) visits was 4, and approximately 19% of patients had ≥3 annual admissions. The mean length of stay was 6 days. The readmission rates at 7, 30, 60, and 90 days were 8%, 24.5%, 13.6%, and 10.8%, respectively.

Conclusion

SCD generates a significant economic burden on the Saudi society and the effects on the healthcare system and patients' quality of life are evident in the high ED visits, readmission rates and prolonged hospitalization. Thereupon we advocate the implementation of sickle cell disease-specialized multidisciplinary clinics.

A systematic review to assess the burden of ischemic priapism in patients with sickle cell disease

Introduction

Ischemic priapism is a serious condition characterized by a persistent and painful involuntary erection. Patients with sickle cell disease (SCD) are at an elevated risk of experiencing priapism, with approximately 40% experiencing priapism during their lifetime.

Objectives

This systematic literature review (SLR) sought to identify studies reporting the clinical, humanistic, and economic burden of SCD-related priapism.

Methods

MEDLINE, Embase, Cochrane CENTRAL/CDSR, and 14 congresses were searched. Results were screened against predefined criteria and studies assessing relevant aspects of burden for human patients with SCD-related priapism were included. Outcomes of interest included rates of erectile dysfunction (ED), other disease-related complications, health-related quality of life (HRQoL), and economic burden.

Results

Of 1,236 publications identified, 34 were included. Most studies were retrospective observational (21). Sample size varied widely (range, 15–10,788). Study publication dates ranged from November 1980 through April 2018. Twenty-one studies reported clinical burden, with findings falling into 4 categories-priapism duration, recurrence frequency, incidence/severity of ED, and other complications. Nineteen studies reported humanistic burden, finding limited use of validated HRQoL measures such as the International Index of Erectile Function and the Priapism Impact Profile. Other patient-reported humanistic outcomes included worse scores on sleep-related indices and low rates of satisfactory intercourse. Eight studies reported economic burden. Direct treatment costs ranged from $4,996 for patients without penile operations to $22,906 (2019 USD) for patients receiving transfusions and urologic procedures.

Conclusions

This SLR identified 34 studies providing evidence of the burden of priapism for patients with SCD, including painful complications and diminished physical, mental and sexual function.

Rise of the planet of rare anemias: An update on emerging treatment strategies

Therapeutic options for rare congenital (hemoglobinopathies, membrane and enzyme defects, congenital dyserythropoietic anemia) and acquired anemias [warm autoimmune hemolytic anemia (wAIHA), cold agglutinin disease CAD, paroxysmal nocturnal hemoglobinuria (PNH), and aplastic anemia (AA)] are rapidly expanding. The use of luspatercept, mitapivat and etavopivat in beta-thalassemia and pyruvate kinase deficiency (PKD) improves transfusion dependence, alleviating iron overload and long-term complications. Voxelotor, mitapivat, and etavopivat reduce vaso-occlusive crises in sickle cell disease (SCD). Gene therapy represents a fascinating approach, although patient selection, the toxicity of the conditioning regimens, and the possible long-term safety are still open issues. For acquired forms, wAIHA and CAD will soon benefit from targeted therapies beyond rituximab, including B-cell/plasma cell targeting agents (parsaclisib, rilzabrutinib, and isatuximab for wAIHA), complement inhibitors (pegcetacoplan and sutimlimab for CAD, ANX005 for wAIHA with complement activation), and inhibitors of extravascular hemolysis in the reticuloendothelial system (fostamatinib and FcRn inhibitors in wAIHA). PNH treatment is moving from the intravenous anti-C5 eculizumab to its long-term analog ravulizumab, and to subcutaneous and oral proximal inhibitors (anti-C3 pegcetacoplan, factor D and factor B inhibitors danicopan and iptacopan). These drugs have the potential to improve patient convenience and ameliorate residual anemia, although patient compliance becomes pivotal, and long-term safety requires further investigation. Finally, the addition of eltrombopag significantly ameliorated AA outcomes, and data regarding the alternative agent romiplostim are emerging. The accelerated evolution of treatment strategies will need further effort to identify the best candidate for each treatment in the precision medicine era.

Clinical and laboratory differences between pediatric hospitalized patients with sickle cell disease infected or not by SARS-CoV-2

OBJECTIVE

The aim of this study was to identify clinical and complete blood count differences between pediatric hospitalized patients with sickle cell disease infected or not by SARS-CoV-2 and compare the complete blood count of patients with sickle cell disease infected by SARS-CoV-2 before hospitalization and on admission.

METHODS

This study was a single-center prospective cohort. Data were collected from medical records of pediatric inpatients with sickle cell disease under 18 years old infected or not with SARS-CoV-2 from the first visit to the hospital until discharge and from the last medical appointment. All patients were tested for SARS-CoV-2 by the real-time reverse transcription polymerase chain reaction.

RESULTS

Among 57 pediatric patients with sickle cell disease hospitalized from March to November 2020 in a Brazilian academic hospital, 11 (19.3%) had a positive result for SARS-CoV-2. Patients infected by SARS-CoV-2 had a higher prevalence of comorbidities than the ones who were not infected (63.6 vs. 30.4%; p=0.046). During hospital stay, no clinical or complete blood count differences between groups were found. There was a decrease in eosinophil count on hospital admission in patients with sickle cell disease infected by SARS-CoV-2 (p=0.008).

CONCLUSIONS

Pediatric hospitalized patients with sickle cell disease infected by SARS-CoV-2 had more comorbidities and had a decrease in eosinophil count between hospital admission and the last medical appointment.

Allogeneic hematopoietic stem cell transplantation to cure sickle cell disease: A review

Sickle cell disease (SCD) had first been mentioned in the literature a century ago. Advancement in the molecular basis of the pathophysiology of the disease opens the door for various therapeutic options. Though life-extending treatments are available for treating patients with SCD, allogeneic hematopoietic stem cell transplantation (HSCT) is the only option as of yet. A major obstacle before HSCT to cure patients with SCD is the availability of donors. Matched sibling donors are available only for a small percentage of patients. To expand the donor pool, different contrasting approaches of allogeneic HSCT like T-cell replete and deplete have been tested. None of those tested approaches have been without the risk of GvHD and graft rejection. Other limitations such as transplantation-related infections and organ dysfunction caused by the harsh conditioning regimen need to be addressed on a priority basis. In this review, we will discuss available allogeneic HSCT approaches to cure SCD, as well as recent advancements to make the approach safer. The center of interest is using megadose T-cell-depleted bone marrow in conjugation with donor-derived CD8 veto T cells to achieve engraftment and tolerance across MHC barriers, under reduced intensity conditioning (RIC). This approach is in phase I/II clinical trial at the MD Anderson Cancer Centre and is open to patients with hemoglobinopathies.

Correlation of Asymmetric Dimethyl Arginine Level to Sickle Retinopathy in Children With Sickle Cell Disease

Asymmetric dimethyl arginine (ADMA) is a competitive inhibitor of nitric oxide synthetase especially in L-arginine deficiency, which is the case in sickle cell disease (SCD). we aimed to assess the level of ADMA in children with sickle retinopathy and to correlate it to the degree of retinopathy. In this cross-sectional study 40 children with SCD were included, 20 of them with sickle cell retinopathy (SCR) (group I), 20 with normal fundus examination (group II), and another 20 healthy children served as controls (group III). We measured ADMA level by ELISA and performed fundus examination. Seventeen of the 20 children included in group I had Grade I retinopathy (85%), 2 children had Grade II retinopathy (10%), and 1 child had Grade III retinopathy (5%). ADMA was significantly higher in SCD than controls ( P -value <0.001), and it was even higher in patients with SCR compared those without retinopathy ( P -value <0.002), and there was positive linear correlation between ADMA and the grade of retinopathy. The type of retinopathy detect in the studied patients was the nonproliferative type. In conclusion, ADMA is elevated in children with SCD, and its level is even higher in those who develop SCR.

Amyloid precursor protein in Alzheimer's disease

Amyloid precursor protein (APP) is a membrane protein expressed in several tissues. The occurrence of APP is predominant in synapses of nerve cells. It acts as a cell surface receptor and plays a vital role as a regulator of synapse formation, iron export and neural plasticity. It is encoded by the APP gene that is regulated by substrate presentation. APP is a precursor protein activated by proteolytic cleavage and thereby generating amyloid beta (Aβ) peptides which eventually form amyloid plaques that accumulate in Alzheimer's disease patients' brains. In this chapter, we highlight basic mechanism, structure, expression patterns and cleavage of amyloid plaques, and its diagnosis and potential treatment for Alzheimer's disease.

Advances in CRISPR therapeutics

The clustered regularly interspaced short palindromic repeats (CRISPR) renaissance was catalysed by the discovery that RNA-guided prokaryotic CRISPR-associated (Cas) proteins can create targeted double-strand breaks in mammalian genomes. This finding led to the development of CRISPR systems that harness natural DNA repair mechanisms to repair deficient genes more easily and precisely than ever before. CRISPR has been used to knock out harmful mutant genes and to fix errors in coding sequences to rescue disease phenotypes in preclinical studies and in several clinical trials. However, most genetic disorders result from combinations of mutations, deletions and duplications in the coding and non-coding regions of the genome and therefore require sophisticated genome engineering strategies beyond simple gene knockout. To overcome this limitation, the toolbox of natural and engineered CRISPR-Cas systems has been dramatically expanded to include diverse tools that function in human cells for precise genome editing and epigenome engineering. The application of CRISPR technology to edit the non-coding genome, modulate gene regulation, make precise genetic changes and target infectious diseases has the potential to lead to curative therapies for many previously untreatable diseases.

Proliferative Sickle Cell Retinopathy in the Retinal Periphery Detected by Ultra-Widefield Imaging: A Case Report

Sickle cell proliferative retinopathy usually presents first in the peripheral retina and the ability to extend and enhance our visualization of the peripheral retina would allow for superior clinical decision-making. In our practice, we had a 28-year-old patient diagnosed with major sickle cell disease of the homozygous type SS (HbSS) that presented with sickle cell proliferative retinopathy detected by ultra-widefield imaging in the nasal side of the left fundus. At follow-up, neovascularization was detected in the extreme nasal periphery of the left eye by ultra-widefield imaging fluorescein angiography with right gaze. The case was graded as Goldberg stage 3, and the patient was administered photocoagulation treatment. With further advancements in the quality and modality of peripheral retinal imaging, novel proliferative lesions can be detected and appropriately managed much earlier than was previously possible. Ultra-widefield imaging allows for the visualization of the central 200 degrees of the retina but, with gaze view, peripheral retina beyond 200 degrees can be reached.

Real-World Evidence on Disease Burden and Economic Impact of Sickle Cell Disease in Italy

A real-world analysis was conducted in Italy among sickle cell disease (SCD) patients to evaluate the epidemiology of SCD, describe patients' characteristics and the therapeutic and economic burden. A retrospective analysis of administrative databases of various Italian entities was carried out. All patients with ≥1 hospitalization with SCD diagnosis were included from 01/2010-12/2017 (up to 12/2018 for epidemiologic analysis). The index date corresponded to the first SCD diagnosis. In 2018, SCD incidence rate was 0.93/100,000, the prevalence was estimated at 13.1/100,000. Overall, 1816 patients were included. During the 1st year of follow-up, 50.7% of patients had one all-cause hospitalization, 27.8% had 2, 10.4% had 3, and 11.1% had ≥4. Over follow-up, 6.1-7.2% of patients were treated with SCD-specific, 58.4-69.4% with SCD-related, 60.7-71.3% with SCD-complications-related drugs. Mean annual number per patient of overall treatments was 14.9 ± 13.9, hospitalizations 1.1 ± 1.1, and out-patient services 5.3 ± 7.6. The total mean direct cost per patient was EUR 7918/year (EUR 2201 drugs, EUR 3320 hospitalizations, and EUR 2397 out-patient services). The results from this real-world analysis showed a high disease burden for SCD patients with multiple hospitalizations during the follow-up. High healthcare resource utilization and costs were associated with patient' management and were most likely underestimated since indirect costs and Emergency Room admissions were not included.

Towards an appropriate African framework for public engagement with human genome editing: a call to synergistic action

The CRISPR-Cas9 system has revolutionised the biotechnology of human genome editing. Human germline gene editing promises exponential benefits to many in Africa and elsewhere, especially those affected by the highly prevalent monogenic disorders - for which, thanks to CRISPR, a relatively safe heritable radical therapy is now possible. Africa evidently presents a unique opportunity for empirical research in human germline gene editing because of its high prevalence of monogenic disorders. Critically, however, germline gene editing has raised serious ethical concerns especially because of the significant risks of inadvertent and intentional misuse of its transgenerational heritability. Calls for due prudence have become even more pronounced in the wake of the 2018 case of He Jiankui’s ‘CRISPR’d babies’. Meanwhile, Africa is seriously lagging in articulating its position on human genome editing. Conspicuously, there has been little to no attempt at comprehensively engaging the African public in discussions on the promises and concerns about human genome editing. Thus, the echoing key question remains as to how Africa should prudently embrace and govern this revolutionary biotechnology. In this article, therefore, I lay the groundwork for the possible development of an appropriate African framework for public engagement with human genome editing and call upon all stakeholders to urgent synergistic action. I particularly highlight the World Health Organisation’s possible leadership role in promptly establishing the requisite expert working group for this urgent need.

Evidence-based obstetric management of women with sickle cell disease in low-income countries

Pregnancy in women with sickle cell disease (SCD) is fraught with complications, some of which are life-threatening. Managing pregnancy in these women can be challenging, especially with poor resources, which is often the case in low-income countries. In Nigeria, for instance, up to 90% of patients pay out of pocket for medical care due to the poorly developed health insurance system, and this worsens the morbidity and mortality associated with this condition. We describe a pragmatic approach to routinely managing pregnant women with SCD in the antenatal period, showing the feasibility of effective management of these high-risk pregnancies in limited-resource settings. We also present the case of a pregnant Nigerian woman with SCD who has intrauterine growth restriction (IUGR) and acute chest syndrome (ACS), conditions that are life-threatening for the fetus and the mother, respectively, and require prompt intervention. We highlight how we successfully managed this woman in a cost-effective manner by employing relatively inexpensive tests for diagnosis and treating her effectively with oxygen, appropriate antibiotics and manual exchange blood transfusion for the ACS, and finger pulse oximeters to monitor oxygen saturation. We explore pathophysiological concepts to IUGR in women with SCD and briefly discuss the appropriate mode of delivery, including the options for pain relief in labor.

Nutritional Heart Disease and Cardiomyopathies: JACC Focus Seminar 4/4

This JACC Focus Seminar provides an overview of and highlights recently published research on cardiomyopathies and nutritional heart disease that have a higher prevalence in tropical regions. The development of tropical cardiomyopathies and nutritional cardiovascular disease (CVD) is complicated by high rates of poverty, fragmented health care systems, and suboptimal access to health care because of socioeconomic inequalities, leading to the fact that children, adolescents, and young adults are disproportionally affected. Such tropical cardiomyopathies and nutritional CVD that have not been prevalent in high-income countries in the past decades are now reemerging. When treating migrants or refugees, it is important for attending physicians to consider the burden of endemic diseases in the countries of origin and the likelihood that such patients might be affected. In this review, the authors propose an approach for adequate diagnostic work-up leading to appropriate care for those with suspected or confirmed tropical cardiomyopathies and nutritional CVD.

Evaluation of left ventricular systolic function in children with sickle cell anemia: contribution of 2D strain

BACKGROUND

Children with sickle cell anemia (SCA) are at an increased risk of cardiovascular complications. The aim of this study was to assess the role of speckle tracking echocardiography in detecting subclinical myocardial damage in children with SCA.

METHODS

A cross-sectional case-control study was conducted at the echocardiography laboratory of the military hospital of Tunis between July and December 2018. Thirty patients with SCA were included. A control(C) group including 30 normally developing children was selected and matched to the SCA group by sex and age. We compared between the two groups: conventional echocardiographic parameters including cardiac output, left ventricular ejection fraction (LVEF), thickness and the global longitudinal strain (GLS). The echocardiographic measurements were indexed according to body surface area. The left ventricular (LV) GLS association with clinical characteristics and echocardiographic parameters were also evaluated.

RESULTS

Patients and controls were matched for age and sex: the mean age was (11± 2years) in SCA group versus (12± 1 years) in C group with a sex ratio of (1.31 versus 1.27, respectively). Body surface area was comparable. LV hypertrophy and dilation were revealed in the SCA group, whereas measurements were normal in the C group. No significant differences were observed for cardiac output (p=0.4). LVEF were preserved in both groups. However, two-dimensional (2D) LVGLS was impaired in 46% of SCA group (n=14) with mean value of (-21%±3.07 vs -25%±2.98; p<0.01).In SCA group, impaired LVGLS was significantly associated with LV mass (r = - 0.399, p<0.01), LV tele diastolic diameter(r= -0.419, p<0.01) and left atrial volume (r= - 0.399, p< 0.04). In multivariate analysis, LV mass was the only independent factor.

CONCLUSIONS

In the present study, LVGLS measurement revealed subclinical LV systolic impairment in patients with SCA. Therefore, 2D strain could be beneficial to detect the natural history of LV dysfunction in SCA.

Effective therapies for sickle cell disease: are we there yet?

Sickle cell disease (SCD) is a common genetic blood disorder associated with acute and chronic pain, progressive multiorgan damage, and early mortality. Recent advances in technologies to manipulate the human genome, a century of research and the development of techniques enabling the isolation, efficient genetic modification, and reimplantation of autologous patient hematopoietic stem cells (HSCs), mean that curing most patients with SCD could soon be a reality in wealthy countries. In parallel, ongoing research is pursuing more facile treatments, such as in-vivo-delivered genetic therapies and new drugs that can eventually be administered in low- and middle-income countries where most SCD patients reside.

Pregnancy and sickle cell disease: an overview of complications and suggested perinatal care

INTRODUCTION

Pregnancy in women with sickle cell disease (SCD) has been identified as high risk owing to increased incidence of materno-fetal complications across various studies and reports. These complications include consequences related to the underlying hemoglobinopathy; chronic anemia/associated inflammation, and pregnancy related including the risk for thromboembolism, bleeding and maternal mortality. Outcomes of neonates born to women with SCD has been suboptimal over the years with recent improvement due to strict monitoring, preventive and therapeutic measures. Much is yet to be unraveled regarding the optimal management of women with SCD during pregnancy, identifying target hemoglobin, delivery mode or timing among others.

AREAS COVERED

This review includes a summary of available data of the maternal and fetal outcomes; in addition to current recommendations for monitoring and management of women with SCD during pregnancy.

EXPERT OPINION

To have a successful pregnancy, women should be closely monitored, and interventions provided as needed to guarantee adequate management of anemia, as well as prevention, diagnosis and management of disease. They should also be educated regarding their reproductive health, emphasizing that pregnancy is possible, and achieving optimal results depends on providing adequate care in a health care facility with expertise in high-risk pregnancies and SCD.

Assessment of transition readiness to predict health care utilization during transition to adult care in sickle cell disease

BACKGROUND

Transition-age patients with sickle cell disease (SCD) are at risk for poor outcomes associated with incomplete transition readiness and neurocognitive deficits. Study objectives were to: 1) test if a SCD-specific measure of self-management skills was associated with transition outcomes and 2) evaluate if caregiver-reported executive functioning was associated with self-management skills and transition outcomes among youth with SCD.

RESEARCH DESIGN AND METHODS

Youth/caregivers were selected from a longitudinal cohort study. Caregivers completed the Behavior Rating Inventory of Executive Function (BRIEF); caregivers and youth completed the Self-Management Skills Checklist (SMSC) at a median age of 16.8 ± 0.6 years. Non-parametric tests compared SMSC and transition outcomes. Regression assessed the incremental validity of SMSC in predicting transition outcomes.

RESULTS

In total, 95 participants (54% male, 55% severe genotype) completed the SMSC assessment. Most participants (87%) transferred to adult care within six months and 87% were retained for at least 12 months. BRIEF and caregiver-reported SMSC assessments were weakly, negatively correlated (ρ = -0.25, p = 0.0392) but were not significant in predicting transition outcomes (p > 0.05).

CONCLUSIONS

The SMSC and executive function did not predict adult care engagement. Development of readiness assessments that predict care engagement and reflect self-efficacy is important for monitoring transition-aged patients with SCD.

Gattaca as a lens on contemporary genetics: marking 25 years into the film's "not-too-distant" future

The 1997 film Gattaca has emerged as a canonical pop culture reference used to discuss modern controversies in genetics and bioethics. It appeared in theaters a few years prior to the announcement of the "completion" of the human genome (2000), as the science of human genetics was developing a renewed sense of its social implications. The story is set in a near-future world in which parents can, with technological assistance, influence the genetic composition of their offspring on the basis of predicted life outcomes. The current moment-25 years after the film's release-offers an opportunity to reflect on where society currently stands with respect to the ideas explored in Gattaca. Here, we review and discuss several active areas of genetic research-genetic prediction, embryo selection, forensic genetics, and others-that interface directly with scenes and concepts in the film. On its silver anniversary, we argue that Gattaca remains an important reflection of society's expectations and fears with respect to the ways that genetic science has manifested in the real world. In accompanying supplemental material, we offer some thought questions to guide group discussions inside and outside of the classroom.

Cutaneous manifestations of sickle cell disease: an updated review

Sickle cell disease is a common and highly morbid genetic condition that is characterized by multi-system involvement, including numerous cutaneous manifestations. Persistent and recurrent leg ulceration has long been considered the dermatological hallmark of those with sickle cell disease, but there have been recent descriptions of associated infection with rare pathogens and episodes of liverdoid vasculopathy. Growing considerations for this population in the literature include cutaneous reactions to common treatments such as hydroxyurea and clinical management of the intersection between sickle cell disease and conditions like plaque psoriasis. Recent studies have also demonstrated an increased resistance to skin carcinogenesis for those with sickle cell disease through unclear mechanisms. However, though the body of knowledge regarding cutaneous manifestations and considerations of sickle cell disease is slowly expanding, it does not match the considerable disease and symptom burden faced by these patients. More research is needed to better delineate our understanding of these cutaneous manifestations of sickle cell disease to improve outcomes and further management.

Red blood cell alloimmunisation in sickle cell disease patients in the Democratic Republic of the Congo

OBJECTIVES

To determine the prevalence of red blood cell (RBC) alloimmunisation and alloantibody specificity in sickle cell disease (SCD) patients in Kisangani, Democratic Republic of Congo (DRC) in comparison with those followed at the Centre Hospitalier Régional (CHR) de la Citadelle of Liège (Belgium).

BACKGROUND

Data regarding RBC alloimmunisation (immune response of the organism to foreign erythrocyte antigens, antigens that lack on its own RBC) in SCD patients are scarce in sub-Saharan Africa.

METHODS

We conducted a multi-site-based cross-sectional study among 125 SCD patients at Kisangani and 136 at the CHR de la Citadelle of Liège. The diagnosis of SCD was confirmed by high-performance liquid chromatography. Alloantibodies were screened using the agglutination technique on gel cards and their specificity determined using 11 and/or 16 cell panels. Statistical analyses were carried out using SPSS.

RESULTS

The prevalence of RBC alloimmunisation was 9.6% among SCD patients in Kisangani versus 22.8% in those of Liège. At Kisangani as well as at Liège, the median age of alloimmunised patients was higher than that of non-alloimmunised patients, 15.5 years (IQR:4.8-19.8) and 24 years (IQR:14-31) versus 10 years (IQR: 6.5-17) and 17 years (IQR:12-24), respectively. The median number of blood units was higher in both Kisangani and Liège immunised patients compared to non-immunised patients, 8 (IQR:5-11) versus 5 (IQR:3-13) and 41(IQR:6-93) versus 6.5(3-37) respectively. At Kisangani (N = 14), the most frequent antibodies were anti-D (28.6%) and anti-C versus anti-E (13.6%), anti-S (13.6%) and anti-Lea (11.4%) at Liège (N = 44).

CONCLUSIONS

These findings stated that alloimmunisation is a common complication in SCD patients in the DRC. In the resource-limited setting of this country, blood transfusion with minimal ABO, D, C and E antigen matching in addition to the use of compatibility test could significantly reduce the incidence of this complication.

Base-editing-mediated dissection of a γ-globin cis-regulatory element for the therapeutic reactivation of fetal hemoglobin expression

Sickle cell disease and β-thalassemia affect the production of the adult β-hemoglobin chain. The clinical severity is lessened by mutations that cause fetal γ-globin expression in adult life (i.e., the hereditary persistence of fetal hemoglobin). Mutations clustering ~200 nucleotides upstream of the HBG transcriptional start sites either reduce binding of the LRF repressor or recruit the KLF1 activator. Here, we use base editing to generate a variety of mutations in the -200 region of the HBG promoters, including potent combinations of four to eight γ-globin-inducing mutations. Editing of patient hematopoietic stem/progenitor cells is safe, leads to fetal hemoglobin reactivation and rescues the pathological phenotype. Creation of a KLF1 activator binding site is the most potent strategy - even in long-term repopulating hematopoietic stem/progenitor cells. Compared with a Cas9-nuclease approach, base editing avoids the generation of insertions, deletions and large genomic rearrangements and results in higher γ-globin levels. Our results demonstrate that base editing of HBG promoters is a safe, universal strategy for treating β-hemoglobinopathies.

HbS promotes TLR4-mediated monocyte activation and proinflammatory cytokine production in sickle cell disease

Monocytes are considered crucial actors of inflammation in sickle cell disease (SCD), being responsible for an increased production of proinflammatory cytokines such as tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), and IL-6. Although a role of free heme released by intravascular hemolysis has been suspected, the mechanisms underlying monocyte activation in patients with SCD remain unknown. Using purified human hemoglobin (Hb), we demonstrate herein, that cell-free HbS, unlike HbA or heme, is responsible for a major enhancement in the expression of proinflammatory cytokines by human monocytes. This effect was found mediated by direct interaction with the Toll-like receptor 4 (TLR4)/myeloid differentiation factor 2 (MD-2) complex, resulting in the activation of both the nuclear factor-κB (NF-κB) and type I interferon pathways. In Townes SCD mice, injection of HbS, unlike HbA, was responsible for an increased production of proinflammatory cytokines, which was prevented by the TLR4 inhibitor, TAK-242. Our results reveal a novel mechanism of monocyte activation and systemic inflammation in SCD, which opens new promising therapeutic perspectives targeting the HbS-TLR4 interaction.

Asplenia and spleen hypofunction

Asplenia (the congenital or acquired absence of the spleen) and hyposplenism (defective spleen function) are common causes of morbidity and mortality. The spleen is a secondary lymphoid organ that is responsible for the regulation of immune responses and blood filtration. Hence, asplenia or hyposplenism increases susceptibility to severe and invasive infections, especially those sustained by encapsulated bacteria (namely, Neisseria meningitidis, Streptococcus pneumoniae, Haemophilus influenzae type b). Asplenia is predominantly due to splenectomy for either traumatic events or oncohaematological conditions. Hyposplenism can be caused by several conditions, including haematological, infectious, autoimmune and gastrointestinal disorders. Anatomical disruption of the spleen and depletion of immune cells, especially IgM memory B cells, seem to be predominantly responsible for the clinical manifestations. Early recognition of hyposplenism and proper management of asplenia are warranted to prevent overwhelming post-splenectomy infections through vaccination and antibiotic prophylaxis. Although recommendations are available, the implementation of vaccination strategies, including more effective and immunogenic vaccines, is needed. Additionally, screening programmes for early detection of hyposplenism in high-risk patients and improvement of patient education are warranted.

Age- and sex-specific rates of gall bladder disease in children with sickle cell disease

BACKGROUND

Children with sickle cell disease (SCD) have an increased risk for gallstones due to chronic hyperbilirubinemia from hemolysis. Although gallstones are a known complication, there is variability in estimates of disease burden and uncertainty in the association between sex and gall bladder disease (GBD).

METHODS

This was a retrospective cohort study of children with SCD using administrative claims data (January 1, 2014-December 31, 2018). Population-averaged multivariable panel-data logistic regression models were used to evaluate the association between GBD clinical encounters (outcome) and two exposures (age and sex). Annual GBD risk was calculated using predictive margins, adjusting for disease severity, transfusion frequency, and hydroxyurea exposure.

RESULTS

A total of 13,745 individuals (of 21,487 possible) met inclusion criteria. The population was evenly split across sex (49.5% female) with predominantly Medicaid insurance (69%). A total of 946 individuals (6.9%) had GBD, 432 (3.1%) had a gallstone complication, and 487 (3.5%) underwent cholecystectomy. The annual risk of GBD rose nonlinearly from 1 to 5% between ages 1 and 19 years with no difference between males and females. Cholecystectomy occurred primarily in individuals with GBD (87%), and neither age nor sex was associated with cholecystectomy in this population. High disease severity (compared with low) more than doubled the annual risk of GBD at all ages.

CONCLUSIONS

GBD is associated with age but not sex in children with SCD. Neither age nor sex is associated with risk of cholecystectomy. High disease severity increases the rate of GBD at all ages.

Treatment patterns and burden of complications associated with sickle cell disease: A US retrospective claims analysis

Complications associated with sickle cell disease (SCD) that are highly impactful for patients but until recently have been less understood include priapism, nephropathy, and neurologic injury. We conducted a retrospective study using US administrative claims data from July 01, 2013 through March 31, 2020 to analyze incidence of these complications, SCD treatment patterns, and healthcare resource utilization (HCRU) and costs among 2524 pediatric and adult patients with SCD (mean [SD] age 43.4 [22.4] years). The most common treatments during follow-up were short-acting opioids (54.0% of patients), red blood cell transfusion (15.9%), and hydroxyurea (11.0%). SCD complications occurred frequently; in the overall population, the highest follow-up incidences per 1000 person-years were for acute kidney injury (53.1), chronic kidney disease (40.6), and stroke (39.0). Complications occurred across all age groups but increased in frequency with age; notably, acute kidney injury was 69.7 times more frequent among ages 65+ than ages 0-15 (p < 0.001). Follow-up per-patient-per-month HCRU also increased with age; however, all-cause healthcare costs were similarly high for all age groups and were driven primarily by inpatient stays. Patients with SCD across the age spectrum have a high burden of complications with the use of current treatments, suggesting unmet needs for treatment management.

Neurodevelopmental Outcomes in Preterm Children with Sickle Cell Disease

OBJECTIVES

To explore the combined effect of pediatric sickle cell disease (SCD) and preterm birth on cognitive functioning.

METHODS

Cognitive functioning was examined in children ages 6-8 with high risk SCD genotypes born preterm (n = 20) and full-term (n = 59) and lower risk SCD genotypes/no SCD born preterm (n = 11) and full-term (n = 99) using tests previously shown to be sensitive to SCD-related neurocognitive deficits. Factorial ANOVAs and log linear analyses were conducted to examine the relationship between SCD risk, preterm birth status, and cognitive outcomes. Continuous scores were examined for specific tests. Children were categorized as having an abnormal screening outcome if at least one cognitive score was ≥1.5 standard deviations below the population mean.

RESULTS

Children with elevated risk due to high risk SCD and preterm birth performed worse than other groups on a test of expressive language but not on tests that emphasize processing speed and working memory. There was a three-way interaction between preterm status, SCD risk, and abnormal screening outcome, which was largely driven by the increased likelihood of abnormal cognitive scores for children with high risk SCD born preterm.

CONCLUSIONS

The combination of SCD and preterm birth may confer increased risk for language deficits and elevated rates of abnormal cognitive screenings. This suggests that neurodevelopmental risk imparted by comorbid SCD and preterm birth may manifest as heterogenous, rather than specific, patterns of cognitive deficits. Future studies are needed to clarify the domains of cognitive functioning most susceptible to disease-related effects of comorbid SCD and preterm birth.

Sickle cell bone disease and response to intravenous bisphosphonates in children

Children with sickle cell disease (SCD) have the potential for extensive and early-onset bone morbidity. This study reports on the diversity of bone morbidity seen in children with SCD followed at three tertiary centers. IV bisphosphonates were effective for bone pain analgesia and did not trigger sickle cell complications.

INTRODUCTION

To evaluate bone morbidity and the response to intravenous (IV) bisphosphonate therapy in children with SCD.

METHODS

We conducted a retrospective review of patient records from 2003 to 2019 at three Canadian pediatric tertiary care centers. Radiographs, magnetic resonance images, and computed tomography scans were reviewed for the presence of avascular necrosis (AVN), bone infarcts, and myositis. IV bisphosphonates were offered for bone pain management. Bone mineral density was assessed by dual-energy X-ray absorptiometry (DXA).

RESULTS

Forty-six children (20 girls, 43%) had bone morbidity at a mean age of 11.8 years (SD 3.9) including AVN of the femoral (17/46, 37%) and humeral (8/46, 17%) heads, H-shaped vertebral body deformities due to endplate infarcts (35/46, 76%), and non-vertebral body skeletal infarcts (15/46, 32%). Five children (5/26, 19%) had myositis overlying areas of AVN or bone infarcts visualized on magnetic resonance imaging. Twenty-three children (8/23 girls) received IV bisphosphonate therapy. They all reported significant or complete resolution of bone pain. There were no reports of sickle cell hemolytic crises, pain crises, or stroke attributed to IV bisphosphonate therapy.

CONCLUSION

Children with SCD have the potential for extensive and early-onset bone morbidity. In this series, IV bisphosphonates were effective for bone pain analgesia and did not trigger sickle cell complications.

Lived experience with sickle cell disease: Predictors of altruistic participation in clinical research

Researchers have found that research altruism motivates research participation, but little is known about what aspects of lived experience motivate this socially focused altruistic participation when participation emerges at the intersection of illness, identity, and injustice. This study examines adults living with sickle cell disease (n = 235) in the United States enrolled in the INSIGHTS clinical research study to investigate what aspects of the sickle cell disease lived experience, understood here as pain and illness perception, are associated with reporting subsidiary and primary altruistic motivations for participating in clinical research. Results from two binary logistic regressions indicate that pain frequency is positively associated with greater odds of reporting subsidiary altruistic motivations, and pain frequency and pain severity are positively associated with greater odds of citing primary altruistic motivations. Conversely, pain interference and illness perception are associated with lower odds of reporting primary altruistic motivations. These results reveal that for this racialized population, participation, although overwhelmingly altruistic, is rooted in an experience of persistent pain. Researchers must disentangle measures of lived experience in order to better understand what factors underlie and prevent participation.

Sickle cell disease among Latinx in California

INTRODUCTION

After African Americans, Latinx are the second largest population affected by Sickle Cell Disease (SCD) in the U.S. However, research has largely ignored how this devastating rare blood disorder specifically affects Latinx nationwide.

METHODS

This study compared demographics, genotypes, primary insurance, and health care utilization among Latinx and non-Latinx Californians living with SCD, using data from the California SCD Data Collection Program (2016-2018) and newborn screening cases 2000-2017.

RESULTS

Stemming from 6,837 SCD patients, 501(7%) were Latinx. Latinx with SCD (Lx-SCD) were statistically significantly younger than non-Latinx (NLx-SCD) counterparts. Within both groups, females predominated, with 70% being insured by Medicaid. Mean Emergency Department encounters were statistically significantly lower among Lx-SCD adults.

DISCUSSION

Lx-SCD differ in age, genotype, and Emergency Department utilization, when compared to NLx-SCD counterparts in California. Latinx are now the largest racial and/or ethnic group in the US, and their presence in SCD population is expected to grow. Therefore, their specific demographic, genotypic, and health care utilization characteristics merit attention to inform policies and programs that will improve their health.