Sickle-cell disease

Painless recurrent orbital wall infarction secondary to sickle cell disease: A case report

Purpose

Describe the various presentations of the rare entity of orbital wall infarction secondary to sickle cell disease and highlight the importance of magnetic resonance imaging in differentiating the entity from other similar diagnoses.

Observation

A 4-year-old child presented to the hospital with bilateral recurrent painless orbital wall infarction secondary to sickle cell disease. Orbital wall infarctions have been described before in the literature; However, the painless and recurrent nature is intriguing.

Conclusion

Orbital wall infarctions secondary to sickle cell disease represent an unusual presentation of the disease and often pose a diagnostic dilemma. When considering differentiating orbital wall infarctions from other resembling entities, magnetic resonance imaging is considered superior to computed tomography due to its ability to delineate the ischemic changes in the bone marrow, which further aids in the diagnosis. In situations where the orbital wall infarction does not lead to orbital compression syndrome, a conservative approach should suffice.

Targeted therapeutic management based on phytoconstituents for sickle cell anemia focusing on molecular mechanisms: Current trends and future perspectives

The global epidemic of Sickle cell anemia (SCA) is causing thousands of children to die. SCA, a genetic disorder affecting the hemoglobin-globin chain, affects millions globally. The primary physiological issue in these patients is the polymerization of sickle hemoglobin within their red blood cells (RBCs) during their deoxygenating state. The RBC undergoes a sickle shape due to the polymerization of mutant hemoglobin within it and membrane deformation during anoxic conditions. To prevent complications, it is essential to effectively stop the sickling of RBCs of the patients. Various medications have been studied for treating SCA patients, focusing on antisickling, γ-globulin induction, and antiplatelet action. Natural and synthetic anti-sickling agents can potentially reduce patient clinical morbidity. Numerous clinical trials focused on using natural remedies for the symptomatic therapy of SCA. Medicinal plants and phytochemical agents have antisickling properties. Recent studies on plant extracts' natural compounds have primarily focused on in vitro RBCs sickling studies, with limited data on in vivo studies. This review discussed the potential role of phytoconstituents in the management of SCA.

Cefmetazole sodium as an allosteric effector that regulates the oxygen supply efficiency of adult hemoglobin

Allosteric effectors play an important role in regulating the oxygen supply efficiency of hemoglobin for blood storage and disease treatment. However, allosteric effectors that are approved by the US FDA are limited. In this study, cefmetazole sodium (CS) was found to bind adult hemoglobin (HbA) from FDA library (1338 compounds) using surface plasmon resonance imaging high-throughput screening. Using surface plasmon resonance (SPR), the interaction between CS and HbA was verified. The oxygen dissociation curve of HbA after CS interaction showed a significant increase in P50 and theoretical oxygen-release capacity. Acid-base sensitivity (SI) exhibited a decreasing trend, although not significantly different. An oxygen dissociation assay indicated that CS accelerated HbA deoxygenation. Microfluidic modulated spectroscopy showed that CS changed the ratio of the alpha-helix to the beta-sheet of HbA. Molecular docking suggested CS bound to HbA's β-chains via hydrogen bonds, with key amino acids being N282, K225, H545, K625, K675, and V544.The results of molecular dynamics simulations (MD) revealed a stable orientation of the HbA-CS complex. CS did not significantly affect the P50 of bovine hemoglobin, possibly due to the lack of Valβ1 and Hisβ2, indicating that these were the crucial amino acids involved in HbA's oxygen affinity. Competition between the 2,3-Diphosphoglycerate (2,3-DPG) and CS in the HbA interaction was also determined by SPR, molecular docking and MD. In summary, CS could interact with HbA and regulate the oxygen supply efficiency via forming stable hydrogen bonds with the β-chains of HbA, and showed competition with 2,3-DPG.Communicated by Ramaswamy H. Sarma.

Safety and efficacy of L-Glutamine in reducing the frequency of acute complications among patients with sickle cell disease: A randomized controlled study

To evaluate the safety and efficacy of L-glutamine in reducing vaso-occlusive crisis (VOC) and improving cerebral arterial blood flow in children with sickle cell disease (SCD). This is an interventional randomized controlled trial that recruited sixty SCD patients, aged 9.2 ± 3.7 years, who had at least two VOCs during the last 12 months and on a stable dose of hydroxyurea. They were randomly assigned in a 1:1 ratio to receive glutamine (0.3 gm/kg/dose/12h) orally for 24 weeks or the standard of care (SOC). All patients had VOCs in the last year > 3, those on glutamine had a higher number of VOCs and hospitalization for VOC in the last year. There was a decreasing trend in the number, severity, and hospitalization of VOC and a significantly lower cumulative number of VOCs and hospitalizations in the glutamine group than in SOC (p = 0.008, p < 0.001 respectively). Time-averaged mean maximum velocity for the glutamine group had a marginal increase in both middle cerebral arteries, all values remained normal within a normal range, and in both internal carotid arteries, values increased from abnormally low to normal ranges at week 24. Glutamine reduced the number of VOCs and severity and may have a potentially favorable impact on the cerebral arterial flow velocities.

Screening for sickle cell disease: focus on newborn investigations

Drepanocytosis is a genetic disease relevant for its epidemiological, clinical and socio-economic aspects. In our country the prevalence is highly uneven with peaks in former malaria areas, but migration flows in recent years have led to significant changes. In this document we review the screening programs currently existing in Italy with particular emphasis on newborn screening, which in other countries around the world, including within Europe, is at most universal and mandatory. The essential laboratory issues are reviewed, from sampling aspects (cord blood or peripheral), to the analytical (analytical methods dedicated to neonatal screening and adult carrier detection) and post analytical (reporting, informative) ones. An economic analysis based on data collected in the province of Modena is also proposed, clearly showing that neonatal screening is also beneficial from an economic point of view.

Multicenter, phase 1 study of etavopivat (FT-4202) treatment for up to 12 weeks in patients with sickle cell disease

ABSTRACT

Etavopivat is an investigational, once daily, oral, selective erythrocyte pyruvate kinase (PKR) activator. A multicenter, randomized, placebo-controlled, double-blind, 3-part, phase 1 study was conducted to characterize the safety and clinical activity of etavopivat. Thirty-six patients with sickle cell disease (SCD) were enrolled into 4 cohorts: 1 single-dose, 2 multiple ascending doses, and 1 open-label (OL). In the OL cohort, 15 patients (median age 33.0 years [range, 17-55]) received 400 mg etavopivat once daily for 12 weeks; 14 patients completed treatment. Consistent with the mechanism of PKR activation, increases in adenosine triphosphate and decreases in 2,3-diphosphoglycerate were observed and sustained over 12 weeks' treatment. This translated clinically to an increase in hemoglobin (Hb; mean maximal increase 1.6 g/dL [range, 0.8-2.8]), with >1 g/dL increase in 11 (73%) patients during treatment. In addition, the oxygen tension at which Hb is 50% saturated was reduced (P = .0007) with a concomitant shift in point of sickling (P = .0034) to lower oxygen tension in oxygen-gradient ektacytometry. Hemolysis markers (absolute reticulocyte count, indirect bilirubin, and lactate dehydrogenase) decreased from baseline, along with matrix metalloproteinase-9 and erythropoietin. In the OL cohort, adverse events (AEs) were mostly grade 1/2, consistent with underlying SCD; 5 patients had serious AEs. Vaso-occlusive pain episode was the most common treatment-emergent AE (n = 7) in the OL cohort. In this, to our knowledge, the first study of etavopivat in SCD, 400 mg once daily for 12 weeks was well tolerated, resulting in rapid and sustained increases in Hb, improved red blood cell physiology, and decreased hemolysis. This trial was registered at www.ClinicalTrials.gov as #NCT03815695.

Hydroxyurea in the sickle cell disease modern era

INTRODUCTION

Sickle cell disease is an inherited disorder characterized by hemoglobin S polymerization leading to vaso-occlusion and hemolytic anemia. These result in a variety of pathological events, causing both acute and chronic complications. Millions around the world are affected by sickle cell disease with predominance in sub-Saharan Africa. Hydroxyurea was the first drug approved for use in sickle cell disease to reduce the occurrence of painful crises and blood transfusions in patients with frequent, moderate to severe painful crises.

AREAS COVERED

With the development of new therapeutics, the role of hydroxyurea is evolving. This narrative review aims to provide clinical data, safety information, and supplementary evidence for the role of hydroxyurea in the current era of sickle cell disease. A comprehensive literature search of databases, including PubMed and Cochrane Library, was conducted from 1963 to 2024.

EXPERT OPINION

Even though new medications have been approved for sickle cell disease, hydroxyurea remains the gold standard. Hydroxyurea is not only a disease modifier but it has additional clinical benefits, it is affordable, and its longevity has prompted expanded research in areas such as underutilization and pharmacogenomics. As the treatment landscape evolves, hydroxyurea's long-standing record of efficacy and safety continues to support its role as a key agent in disease management.

A Review of Gene Therapies for Hemoglobinopathies

Due to the significant morbidity and mortality of hemoglobinopathies, curative options have long been pursued. The overall goal of gene therapy is to modify a patient's own hematopoietic stem cells to overcome the deleterious effects of the underlying genetic defect by gene addition, gene editing, or gene silencing. Gene addition incorporates genes with superior function than the abnormal gene; gene editing takes advantage of molecular tools such as zinc finger proteins, Transcription Activator-Like Effector Nucleases and Clustered Regularly Interspaced Short Palindromic Repeats coupled with Cas9 proteins (CRISPR-Cas9) which allow for sequence-specific breaks in DNA that disrupt gene function; and gene silencing suppresses gene expression by interference with mRNA transcription/protein translation or epigenetic modification. The majority of gene therapy strategies for hemoglobinopathies have targeted erythroid-specific BCL11A, a major regulator of fetal hemoglobin repression at the gamma-globin locus, in the normal fetal-to-adult hemoglobin switch that occurs shortly after birth. Other goals have involved the incorporation of anti-sickling globins, such as βT87Q or βAS3. Landmark clinical trials of gene therapy in transfusion-dependent thalassemia and sickle cell disease have shown remarkable efficacy and acceptable safety and culminated in recent regulatory approvals of gene therapy for both diseases in Europe and the United States.

Prevalence, patterns, and factors associated with abnormal lung function among children with sickle cell disease in Uganda: a cross-sectional study

BACKGROUND

Pulmonary complications are common among children with sickle cell disease (SCD). However, there is little literature on associated lung function abnormalities in Uganda. We aimed to determine the prevalence, patterns, and factors associated with abnormal lung function among children with SCD in a tertiary care hospital in Uganda.

METHOD

A cross-sectional study was conducted among children aged 6 to 18 years at the SCD clinic (SCC) of Mulago National Super-Specialized Hospital between January 2020 and April 2021. Data on sociodemographic and clinical characteristics was collected using a standardized questionnaire. Laboratory investigations, including a complete blood count and serum lactate dehydrogenase (LDH), were done. Spirometry was performed following the ATS/ERS standards. Multivariable modified Poisson regression analysis was performed to determine factors associated with abnormal lung function.

RESULTS

A total of 332 participants were enrolled. The mean age was 11.7 ± 3.4 years, and 184 (55.4%) were female. Overall, 126 (37.9%) participants had abnormal lung function: 67/126 (53.2%) restrictive, 57/126 (45.2%) obstructive, and 2/126 (1.6%) mixed-ventilatory patterns. Factors associated with abnormal lung function were; serum LDH level > 600UL (aIRR: 1.89 95% CI: 1.2 - 7.4, p = 0.049), a history of acute chest syndrome (aIRR: 1.55, 95% CI: 1.06-2.25, p = 0.024), wasting (aIRR: 1.33, 95%CI: 1.02 - 1.72, p = 0.032), and use of charcoal for household cooking (aIRR: 1.49, 95% CI: 1.03-2.15, p = 0.035).

CONCLUSION

More than one-third of children with SCD in Uganda have lung function abnormalities. Strategies to improve nutrition, reduce exposure to charcoal smoke, and monitoring serum LDH levels may be important in preventing or managing abnormal lung function in this population. The identification of reversible and irreversible airway obstruction in children with sickle cell disease also highlights the need for targeted interventions to address these specific patterns of abnormal lung function.

Knowledge, attitudes, and practices of primary healthcare practitioners in low- and middle-income countries: a scoping review on genetics

Individualised treatment, including genetic services, calls for an increased role of primary healthcare practitioners (pHCPs) in diagnosing and caring for individuals with genetic conditions. PHCPs' genetics knowledge and practices must be current to ensure adequate care. A scoping review was conducted to explore peer-reviewed articles on the knowledge, attitudes, and practices (KAPs) of pHCPs concerning genetics, genetic testing, and genetic services. English-language human genetics/genomics articles published between January 1990 and April 2022 in low- and middle-income countries (LMICs) were included. Twenty-eight articles from 16 LMICs in five World Health Organisation (WHO)-defined regions met the inclusion criteria and showed a steady increase in publications, with varied contributions by region. The Eastern Mediterranean Region (EMR) contributed the most articles (n = 8), while the Western Pacific Region (WPR) had the least (n = 2). Brazil published the most articles (n = 6), while ten countries contributed one article each. Fifteen articles included knowledge, 19 included attitudes towards genetics, and eight included genetic practices. The findings indicate that pHCPs in LMICs lack knowledge of genetics and its applications despite their positive outlook towards genetic services. Barriers such as limited resources, financial constraints, and cultural or religious beliefs hinder access to genetic services. Enhancing pHCPs' genetics education is vital for improving care for those affected by genetic conditions. The scarcity of literature in LMICs emphasises the need for research on educational interventions to improve patient outcomes and family support.

Haemoglobinopathies and other rare anemias in Spain: ten years of a nationwide registry (REHem-AR)

REHem-AR was created in 2013. The progressive implementation of neonatal screening for haemoglobinopathies in Spanish autonomous communities where the registry had not been implemented, as well as the addition of new centres during this period, has considerably increased the sample of patients covered. In this study, we update our previous publication in this area, after a follow-up of more than 5 years. An observational, descriptive, multicentre and ambispective study of adult and paediatric patients with haemoglobinopathies and rare anaemias registered in REHem was performed. The data are from a cross-sectional analysis performed on 1 June, 2023. The study population comprised 1,756 patients, of whom 1,317 had SCD, 214 had thalassaemia and 224 were diagnosed with another condition. Slightly more than one third of SCD patients (37%) were diagnosed based on neonatal bloodspot screening, and the mean age at diagnosis was 2.5 years; 71% of thalassaemia patients were diagnosed based on the presence of anaemia. Vaso-occlusive crisis and acute chest syndrome continue to be the most frequent complications in SCD. HSCT was performed in 83 patients with SCD and in 50 patients with thalassaemia. Since the previous publication, REHem-AR has grown in size by more than 500 cases. SCD and TM are less frequent in Spain than in other European countries, although the data show that rare anaemias are frequent within rare diseases. REHem-AR constitutes an important structure for following the natural history of rare anaemias and enables us to calculate investment needs for current and future treatments.

A Rare Case of Multiple Bone Infarctions and Abnormal Pulmonary Function Tests in a Patient With Compound Heterozygous Hemoglobin S and Type 2 Hereditary Persistence of Fetal Hemoglobin

Sickle cell disease (SCD) is a group of inherited blood disorders characterized by abnormal hemoglobin production, affecting individuals worldwide with varying prevalence across different populations. Manifestations vary, ranging from severe to mild. SCD is characterized by the presence of hemoglobin S (HbS), which distorts erythrocytes upon deoxygenation, leading to sickling. This results in hemolytic anemia, painful vaso-occlusive crises (VOC), and multiple organ damage, including bones, due to microinfarcts. Sickle cell trait (SCT), or carrier status, is not considered an SCD and often runs a benign course. We report a 44-year-old man of African descent presenting with a one-month history of pain in his ankles and feet. He had a prior diagnosis of sickle cell "trait" without previous VOC. Hematological indices were normal. Hemoglobin electrophoresis showed absent HbA, elevated HbS, elevated HbF, and normal HbA2. X-rays and MRI revealed bilateral bone infarction in diaphyses of right proximal and bilateral distal tibias. Molecular analysis of [Formula: see text]-globin revealed compound heterozygous hemoglobin S and type 2 deletion of persistence of fetal hemoglobin (HPFH). Pulmonary function tests revealed restrictive lung disease. A literature review from 1946 to May 2024 via PubMed, EMBASE, and Medline was performed, revealing two cases of HbS-HPFH with avascular necrosis affecting the femoral neck were briefly reported more than 60 years ago. Although pulmonary function tests in SCD typically show a mild restrictive pattern with decreased diffusion capacity and rarely an obstructive pattern, no cases of HbS-HPFH were identified. In conclusion, multiple bone infarctions are extremely rare in HbS-HPFH. Lung and bone diseases might be unrecognized in this unique disorder.

The many faces of sickle cell disease in children: complications in the appendicular skeleton

Sickle cell disease (SCD) is a hereditary red cell disorder with clinical manifestations secondary to sickling or crescent-shaped distortion of the red blood cells. Musculoskeletal complications of SCD are often the main causes for acute and chronic morbidities in children with manifestations including osteomyelitis, osteoporosis and osteonecrosis. This article aims to familiarise the paediatric radiologist with appendicular skeletal complications of SCD in the paediatric population and their imaging appearance.

Revolutionary breakthrough: FDA approves CASGEVY, the first CRISPR/Cas9 gene therapy for sickle cell disease

Sickle cell disease (SCD) is a hereditary hemoglobinopathy resulting from a β-globin chain mutation that causes abnormal hemoglobin (HbS) polymerization and leads to severe complications. Current treatment options primarily focus on symptom management, with limited curative potential. Recently, Casgevy, the first CRISPR/Cas9-based gene therapy for SCD, has received breakthrough FDA approval. Clinical trials have shown that Casgevy administered to patients aged older than or equal to 12 years enables precise modifications in hematopoietic stem cells, resulting in elevated fetal hemoglobin (HbF) levels and a significant reduction in vaso-occlusive events. Unlike conventional treatments, this therapy offers a curative approach and eliminates the need for recurrent transfusions and transplants, thereby improving the quality of life of patients with SCD. Casgevy has emerged as a beacon of hope for SCD patients and signifies a potential paradigm shift in SCD management due to its safety, curative potential, and transformative impact, positioning it as a groundbreaking intervention. Nevertheless, ethical considerations surrounding CRISPR technology and regulatory frameworks must be addressed to ensure responsible application and equitable access to this one-time gene editing therapy. As the authors celebrate this scientific advancement, sustained interdisciplinary collaboration and ethical scrutiny are essential to navigating the evolving landscape of CRISPR technology in medicine. This review aims to provide a detailed insight into the application of Casgevy, challenges associated with its application, future prospects of this therapy, and its comparison with existing treatment options for SCD.

Psychological trauma and post-traumatic growth in parents of children with sickle cell disease

Sickle cell disease (SCD) is a hereditary blood condition characterized by abnormal hemoglobin, leading to chronic hemolysis and vaso-occlusive complications. Caregivers of children with SCD often experience significant distress, akin to post-traumatic stress disorder (PTSD). This study aimed to measure the degree of trauma and post-traumatic growth among parents (caregivers) of children with SCD in the Kingdom of Saudi Arabia. A total of 294 primary caregivers were recruited for this study, through direct phone calls and online outreach using contact information obtained from their primary treating physician in Maternity and Children Hospitals and the Hereditary Blood Diseases Center in Al-Ahsa. Inclusion criteria required caregivers not to be receiving professional mental health care and to have a child with SCD below the age of 18. Results indicate that caregiver gender significantly affected IESR scores, with mothers reporting higher scores than fathers. Family income had a significant effect on IESR as well. In terms of education level, higher-educated caregivers were less likely to experience severe trauma. Significant differences emerged between online and phone interview participants, with online respondents reporting higher post-traumatic growth and higher trauma levels. This study represents a crucial step in understanding the challenges faced by caregivers of children with SCD in Al-Ahsa, Saudi Arabia. However, the study has limitations, including a substantial portion of the sample being from a single clinic and a cross-sectional design.

The Ugandan sickle Pan-African research consortium registry: design, development, and lessons

BACKGROUND

Sub-Saharan Africa bears the highest burden of sickle cell disease (SCD) globally with Nigeria, Democratic Republic of Congo, Tanzania, Uganda being the most affected countries. Uganda reports approximately 20,000 SCD births annually, constituting 6.67% of reported global SCD births. Despite this, there is a paucity of comprehensive data on SCD from the African continent. SCD registries offer a promising avenue for conducting prospective studies, elucidating disease severity patterns, and evaluating the intricate interplay of social, environmental, and genetic factors. This paper describes the establishment of the Sickle Pan Africa Research Consortium (SPARCo) Uganda registry, encompassing its design, development, data collection, and key insights learned, aligning with collaborative efforts in Nigeria, Tanzania, and Ghana SPARCo registries.

METHODS

The registry was created using pre-existing case report forms harmonized from the SPARCo data dictionary and ontology to fit Uganda clinical needs. The case report forms were developed with SCD data elements of interest including demographics, consent, baseline, clinical, laboratory and others. That data was then parsed into a customized REDCap database, configured to suit the optimized ontologies and support retrieval aggregations and analyses. Patients were enrolled from one national referral and three regional referral hospitals in Uganda.

RESULTS

A nationwide electronic patient-consented registry for SCD was established from four regional hospitals. A total of 5,655 patients were enrolled from Mulago National Referral Hospital (58%), Jinja Regional Referral (14.4%), Mbale Regional Referral (16.9%), and Lira Regional Referral (10.7%) hospitals between June 2022 and October 2023.

CONCLUSION

Uganda has been able to develop a SCD registry consistent with data from Tanzania, Nigeria and Ghana. Our findings demonstrate that it's feasible to develop longitudinal SCD registries in sub-Saharan Africa. These registries will be crucial for facilitating a range of studies, including the analysis of SCD clinical phenotypes and patient outcomes, newborn screening, and evaluation of hydroxyurea use, among others. This initiative underscores the potential for developing comprehensive disease registries in resource-limited settings, fostering collaborative, data-driven research efforts aimed at addressing the multifaceted challenges of SCD in Africa.

Patient Evaluation of Patient-Controlled Analgesia for Pain Crises in Sickle Cell Disease

BACKGROUND

Vaso-occlusive crisis causing severe pain can be seen in patients with sickle cell anemia and potent opioids should be used in this process. Although sickle cell disease (SCD) patients use patient-controlled analgesia (PCA), we encountered no study evaluating this method from the participants' perspective.

AIM

This descriptive study aimed to evaluate the use and effectiveness of PCA administered using the Mersin Algology Protocol (MAP) during painful episodes of SCD based on participants reports.

METHODS

After obtaining approval from the local ethics committee, 109 SCD participants using PCA as per the MAP between 2018 and 2020 were recruited for the study. The participants answered a 28-item questionnaire regarding their annual number of pain crises, sites of pain, knowledge about PCA, the number of times they used PCA, and the positive and negative aspects of the PCA method.

RESULTS

The mean age of the participants was 28.80 ± 11.5 years. Ninety-nine (90.8%) of the participants considered PCA superior to other pain management methods they had used previously. The 53 participants (48.6%) who waited for their pain to worsen before administering the demand dose expressed fear of taking high doses of medication. As the number of times a participant used PCA increased, NRS scores for pain at the time of demand dosing decreased from 7-10 to 4-6 (p = .013). Eighty-five (78%) of the participants reported having no problems related to the device or drug while using PCA.

CONCLUSION

We found that PCA was used more correctly by participants with more experience using the device. Participants who delay demand dosing do so because of anxiety about developing dependence and to avoid high doses.

Papillary necrosis, fluid intake, and sickle cell nephropathy: lessons for the clinical nephrologist

Graphical abstract

Bone Disease among Children with Sickle Cell Disease: A Scoping Review of Incidence and Interventions

Background

Children with sickle cell disease (SCD) are more likely to have deficient serum levels of vitamin D for bone metabolism. However, appropriate interventions are essential to prevent its progression and alleviate symptoms.

Purpose

The aim of this study is to determine interventions for managing bone disease in children with SCD.

Methods

This study uses a scoping review. A literature review was conducted using PubMed, CINAHL, ScienceDirect, Scopus, and Google Scholar search engines. The study was eligible for inclusion if it included articles published from 2013 to 2023, full-text, and original study design. Study quality was assessed using the Joanna Briggs Institute (JBI) appraisal tool.

Results

This review identified six studies and 114 children with SCD, including 57 boys (50%) and 57 girls (50%). The majority of SCD types experienced were HbSS (86.84%), HbS-B0 Thal (7.01%), HbSC (5.27%), and the HbSS Arab-Indian haplotype (0.88%). Bone disease problems that often arise in children with SCD include Avascular Necrosis (AVN) (78.08%), Osteonecrosis of the Femoral Head (ONFH) (18.42%), and other bone problems (3.50%). Meanwhile, four types of intervention findings were used in managing bone disease among children with SCD: 1). Surgical procedures 53 (41.09%) included total hip arthroplasty (THA), Osteotomy, and Multiple epiphyseal drilling with Autologous Bone Marrow Implantation (AMBI); 2). Invasive procedures 67 (51.93%) included intravenous bisphosphonates, hydroxyurea (HU), and core decompression (CD) with bone marrow aspirate concentrate injection: 3). Oral pharmacological or Vitamin D3 (cholecalciferol) 4 (3.10%); 4). Non-pharmacology or physical therapy 5 (3.88%).

Conclusion

Our findings highlight that surgical, invasive, pharmacological, and physical therapy interventions positively impact increasing bone mineral density (BMD) and functional improvement of bone disease among children with SCD. The interventions provided excellent functional outcomes with minimal complications and no life-threatening side effects.

Academic achievement in Ugandan children with sickle cell anaemia: A cross-sectional study

Objective

Academic achievement in school-age children is crucial for advancing learning goals. Children with sickle cell anaemia (SCA) in Sub-Saharan Africa may be at risk of disease-associated school difficulties. Limited data exist on the academic achievement of children with SCA in the region. This study aimed to assess academic achievement of children with SCA in Uganda compared to siblings without SCA.

Design and setting

A cross-sectional study conducted at Mulago Hospital SCA Clinic in Uganda.

Participants

School-going children (6-12 years) with SCA and age-matched sibling controls without SCA.

Outcome measures

Academic achievement was tested using the Wide Range Achievement Test, Fourth Edition (WRAT4). Outcome measures were spelling, mathematical computation, word reading, and sentence comprehension by age-normalized Z-scores on the WRAT4 test.

Results

Among 68 SCA and 69 control, the mean age (standard deviation) was 9.44 (2.04) and 9.42 (2.02) years and males were 55.9% and 46.4% respectively. Mean haemoglobin was 7.9 (SD 0.89)g/dL in the SCA group versus 12.8 (SD 0.89)g/dL in the controls, (p<0.001). Children with SCA scored lower in spelling, (mean difference [95% confidence interval] - 0.36 [-0.02 to -0.69], p=0.04) and mathematical computation, (mean difference [95% confidence interval] -0.51 [-0.17 to -0.85], p=0.003) than the controls. In the SCA group, lower scores in spelling correlated with age, while males performed better than females in mathematical computation.

Conclusion

School-aged children with SCA are at risk of poor performance in spelling and mathematical computation. Our findings support the need for educational evaluation and possible support, especially in these two areas.

The Association Between Dental Caries and Salivary Buffering Capacity in Syrian Patients Diagnosed with Sickle Cell Disease

Background Sickle cell disease (SCD) is a genetic disorder caused by mutations in the HBB gene, resulting in the abnormal shape of red blood cells. This condition is accompanied by various oral manifestations including salivary gland dysfunction leading to a heightened susceptibility to dental caries. This disorder is primarily treated with hydroxyurea. This study aims to assess dental caries utilizing the decay, missing, filling teeth (DMFT) index and evaluate salivary buffering capacity in patients diagnosed with SCD (HbSS type). The study also aims to assess the relationship between DMFT and salivary buffering capacity. Additionally, the study aimed to find a correlation between treatment with hydroxyurea and changes in both dental caries and salivary buffering capacity. Methods This case-control study enrolled a total of 100 participants aged between 20 and 50 years. The participants were divided into two groups: the study group, which comprised 70 individuals diagnosed with SCD (HbSS type), who were asked to report their current use of hydroxyurea, and the control group, which included 30 healthy individuals. Dental caries were assessed using the DMFT index, while salivary buffering capacity was measured using a pH meter model 420A device. Results The study group exhibited a mean DMFT index value of 6.39 compared to 5.20 in the control group. This difference was statistically significant (P-value=0.037), indicating higher DMFT values among patients with SCD. Salivary buffering capacity was significantly lower in the study group compared to the control group, with average values of 6.47 and 6.88, (P-value=.022). Interestingly, the administration of hydroxyurea impacted salivary buffering capacity, resulting in lower values for individuals using the drug (P-value=0.039). Conversely, hydroxyurea did not have a significant effect on DMFT values (P-value=0.317). Conclusion SCD increases susceptibility to dental caries and is associated with significant changes in salivary composition. At the same time, the potential negative impact of hydroxyurea is acknowledged.

Iron restriction in sickle cell disease: When less is more

Primum non nocere! Can iron deficiency, an abnormality that causes anemia, benefit people with sickle cell disease (SCD) who already have an anemia? The published literature we review appears to answer this question in the affirmative: basic science considerations, animal model experiments, and noncontrolled clinical observations all suggest a therapeutic potential of iron restriction in SCD. This is because SCD's clinical manifestations are ultimately attributable to the polymerization of hemoglobin S (HbS), a process strongly influenced by intracellular HbS concentration. Even small decrements in HbS concentration greatly reduce polymerization, and iron deficiency lowers erythrocyte hemoglobin concentration. Thus, iron deficiency could improve SCD by changing its clinical features to those of a more benign anemia (i.e., a condition with fewer or no vaso-occlusive events). We propose that well-designed clinical studies be implemented to definitively determine whether iron restriction is a safe and effective option in SCD. These investigations are particularly timely now that pharmacologic agents are being developed, which may directly reduce red cell hemoglobin concentrations without the need for phlebotomies to deplete total body iron.

Mass spectrometry for metabolomics analysis: Applications in neonatal and cancer screening

Chemical analysis by analytical instrumentation has played a major role in disease diagnosis, which is a necessary step for disease treatment. While the treatment process often targets specific organs or compounds, the diagnostic step can occur through various means, including physical or chemical examination. Chemically, the genome may be evaluated to give information about potential genetic outcomes, the transcriptome to provide information about expression actively occurring, the proteome to offer insight on functions causing metabolite expression, or the metabolome to provide a picture of both past and ongoing physiological function in the body. Mass spectrometry (MS) has been elevated among other analytical instrumentation because it can be used to evaluate all four biological machineries of the body. In addition, MS provides enhanced sensitivity, selectivity, versatility, and speed for rapid turnaround time, qualities that are important for instance in clinical procedures involving the diagnosis of a pediatric patient in intensive care or a cancer patient undergoing surgery. In this review, we provide a summary of the use of MS to evaluate biomarkers for newborn screening and cancer diagnosis. As many reviews have recently appeared focusing on MS methods and instrumentation for metabolite analysis, we sought to describe the biological basis for many metabolomic and additional omics biomarkers used in newborn screening and how tandem MS methods have recently been applied, in comparison to traditional methods. Similar comparison is done for cancer screening, with emphasis on emerging MS approaches that allow biological fluids, tissues, and breath to be analyzed for the presence of diagnostic metabolites yielding insight for treatment options based on the understanding of prior and current physiological functions of the body.

The Association of Sickle-Cell Disorders With Diabetic Retinopathy: A Large Database Study

Purpose

To evaluate the association of sickle-cell disease (SCD) and sickle-cell trait (SCT) disease with diabetic retinopathy (DR) in patients with diabetes mellitus (DM).

Design

Population-based, retrospective cohort study utilizing data from the TriNetX Research Network, including 119 million patients across 80 health care organizations worldwide.

Participants

Diabetes mellitus patients (type 1 [T1DM] or 2 [T2DM]), with or without SCD and SCT, were included. Three cohorts were analyzed, including (1) DM patients without SCD, SCT, or sickle-cell/hemoglobin-C; (2) DM with SCD; and (3) DM with SCT.

Methods

All patients with DM were categorized into 3 cohorts based on the presence of SCD and SCT. Each cohort underwent 1:1 propensity score matching for demographics, blood glucose levels, hemoglobin A1C, and other relevant comorbidities.

Main Outcome Measures

Risk of DR in DM patients with and without SCD or SCT.

Results

There was no significant difference in the risk of any T1DR between those with and without SCD. However, for those with SCT, there was a notable twofold increased risk for T1-proliferative DR (PDR) (relative risk [RR]: 2.03; 95% confidence interval [CI]: 1.33-3.01). In contrast, there was an elevated risk for any T2DR in patients with SCD (RR: 1.50; 95% CI: 1.19-1.88), particularly due to higher PDR risks in T2DM patients (RR: 1.83; 95% CI: 1.29-2.60). The risk of mild to moderate T2DM non-PDR was also found to be higher in patients with SCT.

Conclusions

The risk of any DR was increased in T2DM patients with SCD or SCT, with increased risks for PDR in patients with SCT and T1DM. This indicates there may be a potential role of sickle-cell disorders in diabetic eye disease progression.

Financial Disclosures

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Controversies in the pathophysiology of leg ulcers in sickle cell disease

Patients with sickle cell disease (SCD) often experience painful vaso-occlusive crises and chronic haemolytic anaemia, as well as various acute and chronic complications, such as leg ulcers. Leg ulcers are characterized by their unpredictability, debilitating pain and prolonged healing process. The pathophysiology of SCD leg ulcers is not well defined. Known risk factors include male gender, poor social conditions, malnutrition and a lack of compression therapy when oedema occurs. Leg ulcers typically start with spontaneous pain, followed by induration, hyperpigmentation, blister formation and destruction of the epidermis. SCD is characterized by chronic haemolysis, increased oxidative stress and decreased nitric oxide bioavailability, which promote ischaemia and inflammation and consequently impair vascular function in the skin. This cutaneous vasculopathy, coupled with venostasis around the ankle, creates an ideal environment for local vaso-occlusive crises, which can result in the development of leg ulcers that resemble arterial ulcers. Following the development of the ulcer, healing is hindered as a result of factors commonly observed in venous ulceration, including venous insufficiency, oedema and impaired angiogenesis. All of these factors are modulated by genetic factors. However, our current understanding of these genetic factors remains limited and does not yet enable us to accurately predict ulceration susceptibility.

Endurance training and hydroxyurea have synergistic effects on muscle function and energetics in sickle cell disease mice

Sickle cell disease (SCD) is an hemoglobinopathy resulting in the production of an abnormal Hb (HbS) which can polymerize in deoxygenated conditions, leading to the sickling of red blood cells (RBC). These alterations can decrease the oxygen-carrying capacity leading to impaired function and energetics of skeletal muscle. Any strategy which could reverse the corresponding defects could be of interest. In SCD, endurance training is known to improve multiples muscle properties which restores patient's exercise capacity but present reduced effects in anemic patients. Hydroxyurea (HU) can increase fetal hemoglobin production which can reduce anemia in patients. The present study was conducted to determine whether HU can improve the effects of endurance training to improve muscle function and energetics. Twenty SCD Townes mice have been trained for 8 weeks with (n = 11) or without (n = 9) HU. SCD mice muscle function and energetics were analyzed during a standardized rest-exercise-recovery protocol, using Phosphorus-31 Magnetic resonance spectroscopy (31P-MRS) and transcutaneous stimulation. The combination of training and HU specifically decreased fatigue index and PCr consumption while muscle oxidative capacity was improved. These results illustrate the potential synergistic effects of endurance training and HU on muscle function and energetics in sickle cell disease.

Whole-blood transcriptome analysis reveals distinct gene expression signatures in paediatric patients with sickle cell anaemia before and after exercise

Sickle cell anaemia (SCA) patients display elevated levels of circulating pro-inflammatory cytokines and endothelial activation markers compared to healthy peers. The impact of exercise on the pro-inflammatory state in SCA remains unclear. This study aimed to characterize the whole-blood transcriptome profile in response to an acute bout of exercise in paediatric SCA patients. Twenty-three SCA participants (13 ± 3 years, 52% girls) and 17 healthy controls (14 ± 3 years, 29% girls) performed eight 2-min bouts of cycle ergometry interspersed with 1-min rest intervals. Whole-blood transcriptome profile (RNA-seq) was performed before and after exercise. At baseline, gene pathways associated with gas transport in erythrocytes were up-regulated in SCA patients compared to controls. Following exercise, gene pathways associated with innate immunity were altered in both groups. Interaction analyses revealed 160 annotated genes (101 up- and 59 down-regulated) that differentially altered by exercise in SCA patients. Moreover, genes that exhibited a blunted response to exercise in SCA patients were enriched in the IL-17 signalling pathway, suggesting an impaired innate immune response to exercise. This data will contribute to the development of evidence-based exercise prescription guidelines for this patient population.

Double Trouble: COVID-19 Infection Exacerbates Sickle Cell Crisis Outcomes in Hospitalized Patients-Insights from National Inpatient Sample 2020

Background: This study investigated the impact of COVID-19 on patients with sickle cell crisis (SCC) using National Inpatient Sample (NIS) data for the year 2020. Methods: A retrospective cohort analysis was conducted utilizing International Classification of Diseases (ICD-10) codes to identify adults who were admitted with a principal diagnosis of sickle cell crisis. The primary outcomes examined were inpatient mortality, while the secondary outcomes assessed included morbidity, hospital length of stay, and resource utilization. Analyses were conducted with STATA. Multivariate logistic and linear regression analyses were used to adjust for confounding variables. Results: Of 66,415 adult patients with a primary SCC diagnosis, 875 were identified with a secondary diagnosis of COVID-19 infection. Unadjusted mortality rate was higher for SCC patients with COVID-19 (2.28%) compared to those without (0.33%), with an adjusted odds ratio (aOR) of 8.49 (p = 0.001). They also showed increased odds of developing acute respiratory failure (aOR = 2.37, p = 0.003) and acute kidney injury requiring dialysis (aOR = 8.66, p = 0.034). Additionally, these patients had longer hospital stays by an adjusted mean of 3.30 days (p < 0.001) and incurred higher hospitalization charges by an adjusted mean of USD 35,578 (p = 0.005). Conclusions: The SCC patients with COVID-19 presented higher mortality rates, increased morbidity indicators, longer hospital stays, and substantial economic burdens.

Iron incorporation in red blood cells of pediatric sickle cell anemia: a stable isotope pilot investigation

BACKGROUND/OBJECTIVES

Sickle cell anemia (SCA) is marked by hypoxia, inflammation, and secondary iron overload (IO), which potentially modulate hepcidin, the pivotal hormone governing iron homeostasis. The aim was to evaluate the iron incorporation in red blood cells (RBC) in SCA pediatric patients, considering the presence or absence of IO.

SUBJECTS/METHODS

SCA children (n = 12; SCAtotal) ingested an oral stable iron isotope (57Fe) and iron incorporation in RBC was measured after 14 days. Patients with ≥1000 ng/mL serum ferritin were considered to present IO (SCAio+; n = 4) while the others were classified as being without IO (SCAio-; n = 8). Liver iron concentration (LIC) was determined by Magnetic Resonance Imaging (MRI) T2* method.

RESULTS

The SCAio+ group had lower iron incorporation (mean ± SD: 0.166 ± 0.04 mg; 3.33 ± 0.757%) than SCAio- patients (0.746 ± 0.303 mg; 14.9 ± 6.05%) (p = 0.024). Hepcidin was not different between groups. Iron incorporation was inversely associated with serum ferritin level (SCAtotal group: r = -0.775, p = 0.041; SCAio- group: r = -0.982; p = 0.018) and sickle hemoglobin (HbS) presented positive correlation with iron incorporation (r = 0.991; p = 0.009) in SCAio- group. LIC was positively associated with ferritin (SCAtotal: r = 0.921; p = 0.026) and C reactive protein (SCAio+: r = 0.999; p = 0.020).

CONCLUSION

SCAio+ group had lower iron incorporation in RBC than SCAio- group, suggesting that they may not need to reduce their intake of iron-rich food, as usually recommended. Conversely, a high percentage of HbS may indirectly exacerbate hypoxia and seems to increase iron incorporation in RBC.

TRIAL REGISTRATION

This trial was registered at www.ensaiosclinicos.gov.br . Identifier RBR-4b7v8pt.

Ovarian Tissue Cryopreservation for Fertility Preservation in Patients with Hemoglobin Disorders: A Comprehensive Review

Hemoglobin diseases like sickle cell disease (SCD) and β-thalassemia (BT) present fertility challenges for affected patients. SCD and BT result from abnormal hemoglobin production or structure and pose numerous health concerns. Despite medical advancements improving the quality of life or even providing cures, SCD and BT pose unique fertility concerns for women. Young women with these disorders already contend with reduced ovarian reserve and a narrower fertile window, a situation that is compounded by the gonadotoxic effects of treatments like medications, transfusions, stem cell transplants, and gene therapy. While crucial for disease control, these interventions may lead to reproductive health issues, increasing infertility and early menopause risks. Ovarian tissue cryopreservation (OTC) offers potential for future motherhood to women with hemoglobin disorders facing infertility related to curative treatments. OTC involves surgically removing, preparing, and freezing ovarian tissue containing primordial follicles capable of producing mature oocytes, offering advantages over oocyte cryopreservation alone. However, the application of OTC for patients with hemoglobin disorders presents unique challenges, including special health risks, financial barriers, and access to care. This comprehensive literature review delves into the current state of ovarian tissue cryopreservation for fertility preservation in patients with hemoglobin disorders. Empowering patients with informed reproductive choices in the context of their hemoglobin disorders stands as the ultimate goal.

Current and Future Therapeutics for Treating Patients with Sickle Cell Disease

Sickle cell disease (SCD) is the most common genetic blood disorder in the United States, with over 100,000 people suffering from this debilitating disease. SCD is caused by abnormal hemoglobin (Hb) variants that interfere with normal red blood cell (RBC) function. Research on SCD has led to the development and approval of several new SCD therapies in recent years. The recent FDA-approved novel gene therapies are potentially curative, giving patients an additional option besides a hematopoietic bone marrow transplant. Despite the promise of existing therapies, questions remain regarding their long-term pharmacological effects on adults and children. These questions, along with the exorbitant cost of the new gene therapies, justify additional research into more effective therapeutic options. Continual research in this field focuses on not only developing cheaper, more effective cures/treatments but also investigating the physiological effects of the current therapies on SCD patients, particularly on the brain and kidneys. In this article, we undertake a comprehensive review of ongoing clinical trials with completion dates in 2024 or later. Our exploration provides insights into the landscape of current therapeutics and emerging novel therapies designed to combat and potentially eradicate SCD, including the latest FDA-approved gene therapies.

Current Status of Molecular Diagnosis of Hereditary Hemolytic Anemia in Korea

Hereditary hemolytic anemia (HHA) is considered a group of rare hematological diseases in Korea, primarily because of its unique ethnic characteristics and diagnostic challenges. Recently, the prevalence of HHA has increased in Korea, reflecting the increasing number of international marriages and increased awareness of the disease. In particular, the diagnosis of red blood cell (RBC) enzymopathy experienced a resurgence, given the advances in diagnostic techniques. In 2007, the RBC Disorder Working Party of the Korean Society of Hematology developed the Korean Standard Operating Procedure for the Diagnosis of Hereditary Hemolytic Anemia, which has been continuously updated since then. The latest Korean clinical practice guidelines for diagnosing HHA recommends performing next-generation sequencing as a preliminary step before analyzing RBC membrane proteins and enzymes. Recent breakthroughs in molecular genetic testing methods, particularly next-generation sequencing, are proving critical in identifying and providing insight into cases of HHA with previously unknown diagnoses. These innovative molecular genetic testing methods have now become important tools for the management and care planning of patients with HHA. This review aims to provide a comprehensive overview of recent advances in molecular genetic testing for the diagnosis of HHA, with particular emphasis on the Korean context.

The effect of red blood cell disorders on male fertility and reproductive health

Male infertility is defined as a failure to conceive after 12 months of unprotected intercourse owing to suspected male reproductive factors. Non-malignant red blood cell disorders are systemic conditions that have been associated with male infertility with varying severity and strength of evidence. Hereditary haemoglobinopathies and bone marrow failure syndromes have been associated with hypothalamic-pituitary-gonadal axis dysfunction, hypogonadism, and abnormal sperm parameters. Bone marrow transplantation is a potential cure for these conditions, but exposes patients to potentially gonadotoxic chemotherapy and/or radiation that could further impair fertility. Iron imbalance might also reduce male fertility. Thus, disorders of hereditary iron overload can cause iron deposition in tissues that might result in hypogonadism and impaired spermatogenesis, whereas severe iron deficiency can propagate anaemias that decrease gonadotropin release and sperm counts. Reproductive urologists should be included in the comprehensive care of patients with red blood cell disorders, especially when gonadotoxic treatments are being considered, to ensure fertility concerns are appropriately evaluated and managed.

The role of preoperative transfusion in sickle cell disease, a systematic review and meta-analysis

This systematic review and meta-analysis aimed to provide guidance on preoperative blood transfusion strategies for patients with sickle cell disease (SCD). We included all randomized controlled and observational studies exploring the clinical outcomes of preoperative blood transfusion among patients with SCD compared to the conservative transfusion strategy until 14/09/2022. Sixteen studies involving 3486 participants were analysed. The findings revealed a significantly higher bleeding rate in patients who received preoperative transfusion than those who followed a conservative strategy (RR = 4.32, 95% CI 1.75-10.68, P = 0.002, I2 = 0%). However, the two strategies had no significant differences in other clinical outcomes, such as acute chest syndrome, painful crisis, fever, neurological complications, thrombosis, ICU admission, and mortality. It is important to note that all the included studies had a moderate risk of bias. Preoperative transfusion in SCD was associated with a higher bleeding risk but a similar risk in other outcomes compared to conservative strategies. Notably, the increased bleeding risk observed seldom had clinical significance. We recommend individualizing management strategies, considering the overall positive impact of transfusions in reducing complications. Further high-quality studies are needed to refine recommendations.

Hospitalization Events Among Adolescents and Adults With Sickle Cell Disease in a Tertiary Care Center in Central India

BACKGROUND

Sickle cell disease (SCD) is an inherited red blood cell disorder, wherein mutation causes the substitution of glutamic acid to valine at the sixth position of the β-globin chain. These include sickle cell anemia (homozygous sickle mutation), sickle-beta thalassemia, and hemoglobin SCD. The clinical manifestations of SCD are protean. Individuals with SCD suffer from both acute and chronic complications, which include recurring episodes of pain commonly called vaso-occlusive crisis (VOC) - acute chest syndrome (ACS); aseptic necrosis of the bone; micro-infarction of the spleen, brain, and kidney; infections; stroke; and organ damage affecting every part of the body. SCD necessitates frequent hospitalizations because of severe complications, which pose a significant burden on caregivers and economic strain on healthcare systems. The pattern of hospital admission with SCD varies in different parts of the world.

OBJECTIVE

This study aimed to determine the causes of hospitalization among adolescent and adult patients with SCD and to determine factors associated with their hospital stay.

METHODS

The study was a hospital-based prospective observational study comprising adolescent and adult patients diagnosed with SCD, aged 15-45 years, who were hospitalized in the Department of General Medicine at All India Institute of Medical Sciences in Raipur from August 2021 to August 2022.

RESULT

According to our study, the primary reason for hospitalization was a painful crisis, accounting for 63% of cases, followed by infection (17%), ACS (11%), and acute hemolytic crisis (9%). Notably, we did not observe any significant differences between genders and causes of admission (p > 0.05). Joint pain (p = 0.005), back pain (p = 0.001), and chest pain (p = 0.001) were more frequently reported by adults over the age of 19. In addition, our analysis of the duration of hospital stays and various factors revealed that patients admitted for infections had a significantly longer mean hospital stay duration (p = 0.040).

CONCLUSION

Acute painful crises were the primary cause of hospital admission among individuals with SCD; many patients also encountered infections and ACS. Furthermore, patients who experienced infections and VOC had a lengthier duration of hospital stay. Therefore, it is essential to provide them with comprehensive instructions on various preventive measures against infections and the factors that trigger painful crises.

Revolutionising healing: Gene Editing's breakthrough against sickle cell disease

Recent advancements in gene editing illuminate new potential therapeutic approaches for Sickle Cell Disease (SCD), a debilitating monogenic disorder caused by a point mutation in the β-globin gene. Despite the availability of several FDA-approved medications for symptomatic relief, allogeneic hematopoietic stem cell transplantation (HSCT) remains the sole curative option, underscoring a persistent need for novel treatments. This review delves into the growing field of gene editing, particularly the extensive research focused on curing haemoglobinopathies like SCD. We examine the use of techniques such as CRISPR-Cas9 and homology-directed repair, base editing, and prime editing to either correct the pathogenic variant into a non-pathogenic or wild-type one or augment fetal haemoglobin (HbF) production. The article elucidates ways to optimize these tools for efficacious gene editing with minimal off-target effects and offers insights into their effective delivery into cells. Furthermore, we explore clinical trials involving alternative SCD treatment strategies, such as LentiGlobin therapy and autologous HSCT, distilling the current findings. This review consolidates vital information for the clinical translation of gene editing for SCD, providing strategic insights for investigators eager to further the development of gene editing for SCD.

Investigation on the relationship between hemoglobin concentration and stroke risk: a bidirectional Mendelian randomization study

Background

The relationship between hemoglobin concentration and stroke has garnered significant interest in the research community. However, findings from published observational epidemiological studies on this relationship have been inconclusive. By using publicly available genome-wide association study (GWAS) aggregated statistics, a two-sample Mendelian randomization analysis is conducted to explore the causal relationship between hemoglobin concentration and stroke.

Methods

Summary statistics data from UK Biobank for hemoglobin concentration and from the FinnGen R9 and MEGASTROKE consortium for stroke are used. A series of quality control steps are taken to select eligible instrumental SNPs closely related to exposure. In order to make the conclusion more robust and reliable, several robust analysis methods are employed including inverse variance weighted, weighted median, MR-Egger regression, which are based on different assumptions of two-sample MR Analysis. Meanwhile, sensitivity analyses such as pleiotropy test and MR-Egg regression, are performed to mitigate horizontal pleiotropy and heterogeneity.

Results

The two-sample Mendelian randomized study indicates a negative association between hemoglobin concentration and stroke, suggesting that hemoglobin concentration acts as a protective factor against stroke. From the FinnGen database, there is a negative association between hemoglobin concentration and stroke, with an odds ratio (OR) of 0.82 and a 95% confidence interval (CI) of 0.73-0.92, p = 0.0006. Similarly, the MEGASTROKE database findings reinforce this observation. The negative association between hemoglobin concentration and stroke (OR: 0.91, 95%CI: 0.83-1.00, p = 0.040), ischemic stroke (OR: 0.87, 95%CI: 0.79-0.96, p = 0.004), and cardiogenic stroke (OR: 0.82, 95% CI: 0.69-0.99, p = 0.039) further suggests that higher hemoglobin levels might confer a protective effect against these conditions.

Conclusion

Hemoglobin concentration serves as a protective factor against stroke, and managing abnormal hemoglobin levels can effectively reduce the incidence of stroke.

Unraveling the Complexity of Vaso-Occlusive Crises in Sickle Cell Disease: Insights from a Resource-Limited Setting

Background/Objectives: This study investigated vaso-occlusive crises (VOCs) in sickle cell disease in Lubumbashi, Democratic Republic of Congo, aiming to understand the disease complexities amidst limited resources. With sickle cell hemoglobinopathies on the rise in sub-Saharan Africa, this nine-year study explored factors associated with VOCs and hematological components. Methods: This study comprised 838 patients, analyzing VOCs and hematological changes over time. Demographic characteristics and blood composition changes were carefully categorized. A total of 2910 crises were observed and managed, with analyses conducted on severity, localization, and age groups using statistical methods. Results: The majority of crises were mild or moderate, primarily affecting osteoarticular regions. Statistical analysis revealed significant disparities in crisis intensity based on location and age. The association between blood samples and the number of comorbidities was investigated. Significant positive associations were found for all parameters, except monocytes, indicating a potential link between blood variables and complication burden. Survival analysis using Cox regression was performed to predict the probability of experiencing a second crisis. No significant effects of medication or localization were observed. However, intensity (p < 0.001), age (p < 0.001), and gender (p < 0.001) showed significant effects. Adjusted Hazard Ratios indicated increased risk with age and male gender and reduced risk with mild or severe crisis intensity compared to light. Conclusions: This research sheds light on the complexities of VOCs in resource-limited settings where sickle cell disease is prevalent. The intricate interplay between clinical, laboratory, and treatment factors is highlighted, offering insights for improved patient care. It aims to raise awareness of patient challenges and provide valuable information for targeted interventions to alleviate their burden.

Acute care utilization among individuals with sickle cell disease and related cardiopulmonary and renal complications

Cardiopulmonary and renal end organ (CPR) complications are associated with early mortality among individuals with sickle cell disease (SCD). However, there is limited knowledge regarding acute care utilization for individuals with SCD and CPR complications. Our objective was to determine the prevalence of CPR complications in a state specific SCD population and compare acute care utilization among individuals with and without CPR complications. We leveraged 2017-2020 data for individuals with SCD identified by the Sickle Cell Data Collection program in Wisconsin. The prevalence of CPR complications is determined for distinct age groups. Generalized linear models adjusted for age compared the rate of acute care visits/person/year among individuals who had cardiopulmonary only, renal only, both cardiopulmonary and renal, or no CPR complications. There were 1378 individuals with SCD, 52% females, mean (SD) age 28.3 (18.5) years; 48% had at least one CPR complication during the study period. The prevalence of CPR complications was higher in adults (69%) compared to pediatric (15%) and transition (51%) groups. Individuals with SCD and cardiopulmonary complications had higher acute visit rates than those without CPR complications (5.4 (IQR 5.0-5.8) vs 2.4 (IQR 2.1-2.5), p <0.001)). Acute care visit rates were similar between individuals with SCD who had renal only complications and no CPR complications (2.7 (IQR 2.5-3.0) vs 2.4 (2.1-2.5), p = 0.24). The high acute care visit rates, especially for those with cardiopulmonary complications, warrant further investigation to understand risk factors for CPR complications, the underlying reasons and identify effective disease management strategies.

TSH Receptor Reduces Hemoglobin S Polymerization and Increases Deformability and Adhesion of Sickle Erythrocytes

SCD is a hereditary disorder caused by genetic mutation in the beta-globin gene, resulting in abnormal hemoglobin, HbS that forms sickle-shaped erythrocytes under hypoxia. Patients with SCD have endocrine disorders and it was described that 7% of these patients have clinical hypothyroidism. Recent studies have shown that mature erythrocytes possess TSH receptors. Thus, we aimed to assess the effects of TSH on SCD erythrocytes. The experiments were conducted using different concentrations of TSH (1, 2, 3, and 5 mIU/L). In HbS polymerization assay, erythrocytes were exposed to TSH in hypoxia to induce polymerization, and measurements were taken for 30 minutes. The deformability assay was made using Sephacryl-S 500 columns to separate deformable from nondeformable cells. Static adhesion test utilized thrombospondin to assess erythrocyte adhesion in the presence of TSH. TSH at all contractions were able to reduce polymerization of HbS and increase deformability. The static adhesion of erythrocytes at the lowest concentrations of 1 and 2 mIU/L were increased, but at higher contractions of 3 and 5 mIU/L, static adhesion was not modulated. The results suggest that TSH has potential involvement in the pathophysiology of sickle cell disease by inhibiting HbS polymerization, positively modulating deformability and impacting static adhesion to thrombospondin.

Diagnosis and management of chronic thromboembolic pulmonary hypertension (CTEPH) in sickle cell disease: A review

Pulmonary hypertension in sickle cell disease (SCD) is a complex phenomenon resulting from multiple overlapping etiologies, including pulmonary vasoconstriction in the setting of chronic hemolytic anemia, diastolic dysfunction, and chronic thromboembolic disease. The presence of pulmonary hypertension of any cause in SCD confers a significant increase in mortality risk. Evidence to guide the management of patients with sickle cell disease and chronic thromboembolic pulmonary hypertension (CTEPH) is scant and largely the realm of case reports and small case series. Centered on a discussion of a complex young patient with hemoglobin hemoglobin SC who ultimately underwent treatment with pulmonary thromboendarterectomy, we review the available literature to guide management and discuss and overview of treatment of CTEPH in SCD, considering the unique considerations and challenges facing patients suffering from this multisystem disease.

The crucial role of NRF2 in erythropoiesis and anemia: Mechanisms and therapeutic opportunities

The nuclear factor erythroid 2-related factor 2 (NRF2) is a transcription factor crucial in cellular defense against oxidative and electrophilic stresses. Recent research has highlighted the significance of NRF2 in normal erythropoiesis and anemia. NRF2 regulates genes involved in vital aspects of erythroid development, including hemoglobin catabolism, inflammation, and iron homeostasis in erythrocytes. Disrupted NRF2 activity has been implicated in various pathologies involving abnormal erythropoiesis. In this review, we summarize the progress made in understanding the mechanisms of NRF2 activation in erythropoiesis and explore the roles of NRF2 in various types of anemia. This review also discusses the potential of targeting NRF2 as a new therapeutic approach to treat anemia.

Models of care for sickle cell disease in low-income and lower-middle-income countries: a scoping review

Sickle cell disease has a growing global burden falling primarily on low-income countries (LICs) and lower-middle-income countries (LMICs) where comprehensive care is often insufficient, particularly in rural areas. Integrated care models might be beneficial for improving access to care in areas with human resource and infrastructure constraints. As part of the Centre for Integration Science's ongoing efforts to define, systematise, and implement integrated care delivery models for non-communicable diseases (NCDs), this Review explores models of care for sickle cell disease in LICs and LMICs. We identified 99 models from 136 studies, primarily done in tertiary, urban facilities in LMICs. Except for two models of integrated care for concurrent treatment of other conditions, sickle cell disease care was mostly provided in specialised clinics, which are low in number and accessibility. The scarcity of published evidence of models of care for sickle cell disease and integrated care in rural settings of LICs and LMICs shows a need to implement more integrated models to improve access, particularly in rural areas. PEN-Plus, a model of decentralised, integrated care for severe chronic non-communicable diseases, provides an approach to service integration that could fill gaps in access to comprehensive sickle cell disease care in LICs and LMICs.

The interaction between particles and vascular endothelium in blood flow

Particle-based drug delivery systems have shown promising application potential to treat human diseases; however, an incomplete understanding of their interactions with vascular endothelium in blood flow prevents their inclusion into mainstream clinical applications. The flow performance of nano/micro-sized particles in the blood are disturbed by many external/internal factors, including blood constituents, particle properties, and endothelium bioactivities, affecting the fate of particles in vivo and therapeutic effects for diseases. This review highlights how the blood constituents, hemodynamic environment and particle properties influence the interactions and particle activities in vivo. Moreover, we briefly summarized the structure and functions of endothelium and simulated devices for studying particle performance under blood flow conditions. Finally, based on particle-endothelium interactions, we propose future opportunities for novel therapeutic strategies and provide solutions to challenges in particle delivery systems for accelerating their clinical translation. This review helps provoke an increasing in-depth understanding of particle-endothelium interactions and inspires more strategies that may benefit the development of particle medicine.

Folic Acid in the Treatment of Sickle Cell Disease: A Systematic Review

Sickle cell disease (SCD) is a group of inherited genetic disorders that is caused by a mutation in the gene that codes for hemoglobin subunit β. This systematic review aimed to evaluate the effect of folic acid in the treatment of SCD patients. We retrieved 3730 articles from PubMed, PubMed Central, Google Scholar, and ScienceDirect databases. We employed a search technique that involved framing keywords, such as folic acid, folate, and sickle cell illness, and the Medical Subject Headings (MeSH) strategy in PubMed. We chose research articles that had been published during the last 10 years, as well as case reports, systematic reviews and meta-analyses, literature reviews, randomized controlled trials, and observational studies. Exclusion criteria included paid full-text articles, abstracts, non-English studies, and patients who do not have SCD. The 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria were used in the design of our systematic review. It was found that the majority of SCD patients were receiving regular folic acid supplements and that their plasma folate levels were either increased or within normal range, with no discernible impact on other clinical outcomes such as hemoglobin levels, infections, or pain crises. SCD patients produce more red blood cells than healthy individuals, and nearly all SCD patients receive daily folic acid supplements. On the other hand, not enough information is available on folic acid's potential benefits in the management of SCD; thus, there is a need for more large clinical trials.

Roles of Pharmacists in the Management of Sickle Cell Disease in Adults: A Narrative Review

Background: Sickle cell disease (SCD) is an autosomal, recessive, genetic condition of the sickle cell genes. It affects about 100 000 people in the United States where an estimated 1 out of every 365 black children and 1 out of every 13 black children will be born with SCD and sickle cell trait, respectively. Severe and unpredictable pain crisis are the leading cause of emergency department visit for adult patients with SCD and account for 90% of inpatient hospitalizations and 85% of all acute medical care, as well as high usage of medical resources. The care of patients with SCD is complex and requires a multidisciplinary approach. With a few pharmacotherapeutic options to reduce SCD complications and pain episodes, the role of pharmacists in the medication management is unclear. This article aims to outline the potential role of pharmacists in SCD management. Data sources: The authors searched Medline, PubMed, EMBASE, and Scopus from January 1, 1990 to August 31, 2022, for primary literature that assessed the role of pharmacists in managing patients with SCD. Results: The authors identified relevant studies and summarized the role of pharmacists in SCD management. Conclusions: Access to comprehensive health care is essential to ensure that patients with SCD have decreased hospitalizations and good health-related quality of life. Pharmacists are an integral part of the multidisciplinary health-care team and can help patients with SCD navigate the complexities of health care. Pharmacists are medication experts who are positioned to ensure comprehensive care in the acute and chronic SCD management.

[Sickle cell disease in French Guiana: assessing 30 years of neonatal screening (1992-2021)]

Background

Sickle cell disease is one of the most common genetic diseases in France. In French Guiana, neonatal screening was introduced in 1992, at the same time as other screening programs for childhood diseases. The aim of this study is to describe the organization of newborn screening for sickle cell disease in French Guiana.

Materials and methods

We used several data sources: data collected from hospital records since 2005, activity reports from the national neonatal screening program and data from screening campaigns organized by the Drepaguyane association between 2010 and 2021 on 1,300 subjects. Blood samples from newborns are collected by capillary or venous sampling and absorbed on blotting paper (Guthrie) at the same time as those for other neonatal screenings. The dried papers are sent to the inter-regional laboratory in Lille, for further processing. In Saint-Laurent-du-Maroni, in order to reduce the proportion of people lost to follow-up, a double screening is carried out and the results are returned before discharge from the maternity hospital. All data were entered into an anonymous Excel file. The data were analyzed using STATA software.

Results

Among the 175,593 screened neonates between 1992 and 2021, screening detected 823 infants with sickle cell disease and 17,950 heterozygotes. Sickle cell genotypes include 493 SS (60%), 302 SC (37%) and 28 S-Beta-thalassemia (3%). The incidence of sickle cell disease was 1/213, 95% CI [1/236-1/204], and that of heterozygotes 1/10, IC 95% [1/12-1/8]. The majority of these children (52%) were from the Maroni region. The delay between screening and test results was 7 days. Only pathological results (homozygous, heterozygous) were communicated to parents and/or the attending physician by post. These data confirm the upward trend in the number of children screened for sickle cell disease in French Guiana. Data from screening campaigns organized by the Drepaguyane association have enabled to describe the distribution of the various abnormal hemoglobin fractions, and to confirm that HbS is more frequent in Western French Guiana. In Cayenne, in 2021, the active file comprised 699 patients, including 266 children under 18 years old.

Discussion and conclusion

This study provides valuable data on 30 years of neonatal screening for sickle cell disease in French Guiana, and on the evolution of sickle cell disease patients. It confirms that French Guiana is the French territory with the highest incidence of sickle cell disease. This incidence continues to rise over time. The study reveals the improvement in the organization of sickle cell disease management in French Guiana between 1992, when screening was introduced, and the present day. It highlights the role of patient associations in the fight against this disease, by organizing awareness and screening campaigns. These data will be used to guide public health policies in the pursuit of improved care and primary prevention.

Clearance of VWF by hepatic macrophages is critical for the protective effect of ADAMTS13 in sickle cell anemia mice

ABSTRACT

Although it is caused by a single-nucleotide mutation in the β-globin gene, sickle cell anemia (SCA) is a systemic disease with complex, incompletely elucidated pathologies. The mononuclear phagocyte system plays critical roles in SCA pathophysiology. However, how heterogeneous populations of hepatic macrophages contribute to SCA remains unclear. Using a combination of single-cell RNA sequencing and spatial transcriptomics via multiplexed error-robust fluorescence in situ hybridization, we identified distinct macrophage populations with diversified origins and biological functions in SCA mouse liver. We previously found that administering the von Willebrand factor (VWF)-cleaving protease ADAMTS13 alleviated vaso-occlusive episode in mice with SCA. Here, we discovered that the ADAMTS13-cleaved VWF was cleared from the circulation by a Clec4f+Marcohigh macrophage subset in a desialylation-dependent manner in the liver. In addition, sickle erythrocytes were phagocytized predominantly by Clec4f+Marcohigh macrophages. Depletion of macrophages not only abolished the protective effect of ADAMTS13 but exacerbated vaso-occlusive episode in mice with SCA. Furthermore, promoting macrophage-mediated VWF clearance reduced vaso-occlusion in SCA mice. Our study demonstrates that hepatic macrophages are important in the pathogenesis of SCA, and efficient clearance of VWF by hepatic macrophages is critical for the protective effect of ADAMTS13 in SCA mice.

Substance use disorder of equimolar oxygen-nitrous oxide mixture in French sickle-cell patients: results of the PHEDRE study

BACKGROUND

In many countries, nitrous oxide is used in a gas mixture (EMONO) for short-term analgesia. Cases of addiction, with significant misuse, have been reported in hospitalized patients. Patients suffering from sickle cell disease (SCD) could represent a high-risk population for substance use disorder (SUD) due to their significant pain crisis and repeated use of EMONO. The objective of the PHEDRE study was to assess the prevalence of SUD for EMONO in French SCD patients.

RESULTS

A total of 993 patients were included. Among 339 EMONO consumers, only 38 (11%) had a SUD, with very few criteria, corresponding mainly to a mild SUD due to a use higher than expected (in quantity or duration) and relational tensions with the care teams. Almost all patients (99.7%) were looking for an analgesic effect, but 68% of patients were also looking for other effects. The independent risks factors associated with at least one SUD criterion were: the feeling of effects different from the expected therapeutic effects of EMONO, at least one hospitalization for vaso occlusive crisis in the past 12 months and the presence of a SUD for at least one other analgesic drug.

CONCLUSIONS

The use of EMONO was not problematic for the majority of patients. Manifestations of SUD that led to tensions with healthcare teams should alert and lead to an evaluation, to distinguish a true addiction from a pseudoaddiction which may be linked to an insufficient analgesic treatment related to an underestimation of pain in SCD patients.

TRIAL REGISTRATION

Clinical Trials, NCT02580565. Registered 16 October 2015, https://clinicaltrials.gov/.

Aerobic physical capacity and health-related quality of life in children with sickle cell disease

BACKGROUND

Aerobic fitness is a predictor of cardiovascular health which correlates with health-related quality of life in the general population. The aim is to evaluate the aerobic capacity by cardiopulmonary exercise test (CPET) in children with sickle cell disease in comparison with healthy matched controls.

METHODS

Controlled cross-sectional study.

RESULTS

A total of 72 children (24 with sickle cell disease and 48 healthy controls), aged 6-17 years old were enrolled. Children with sickle cell disease had a poor aerobic capacity, with median VO2max Z-score values significantly lower than matched controls (-3.55[-4.68; -2.02] vs. 0.25[-0.22; 0.66], P < 0.01, respectively), and a high proportion of 92% children affected by an impaired aerobic capacity (VO2max Z-score < -1.64). The VO2max decrease was associated with the level of anemia, the existence of a homozygote HbS/S mutation, restrictive lung disease and health-related quality of life.

CONCLUSION

Aerobic capacity is poor in children with sickle cell disease. VO2max decrease is associated with the level of anemia, the existence of a homozygote HbS/S mutation, lung function, and health-related quality of life. These results represent a signal in favor of early initiation of cardiac rehabilitation in patients with sickle cell disease.

CLINICAL TRIALS

NCT05995743.

IMPACT

Aerobic fitness is a predictor of cardiovascular health which correlates with health-related quality of life in the general population. Aerobic capacity (VO2max) is poor in children with sickle cell disease, despite the absence of any pattern of heart failure. VO2max decrease was associated with the level of anemia, the existence of a homozygote HbS/S mutation, restrictive lung disease, and health-related quality of life. These results are in favor of early initiation of cardiac rehabilitation in children with sickle cell disease.