A Critical Review of Sickle Cell Disease Burden and Challenges in Sub-Saharan Africa

Sickle Cell Disease: Current Drug Treatments and Functional Foods with Therapeutic Potential

Sickle cell anemia (SCA), the most common form of sickle cell disease (SCD), is a genetic blood disorder. Red blood cells break down prematurely, causing anemia and often blocking blood vessels, leading to chronic pain, organ damage, and increased infection risk. SCD arises from a single-nucleotide mutation in the β-globin gene, substituting glutamic acid with valine in the β-globin chain. This review examines treatments evaluated through randomized controlled trials for managing SCD, analyzes the potential of functional foods (dietary components with health benefits) as a complementary strategy, and explores the use of bioactive compounds as functional food ingredients. While randomized trials show promise for certain drugs, functional foods enriched with bioactive compounds also hold therapeutic potential. Further research is needed to confirm clinical efficacy, optimal dosages, and specific effects of these compounds on SCD, potentially offering a cost-effective and accessible approach to managing the disease.

Update on the practice of premarital screening for sickle cell traits in Africa: a systematic review and meta-analysis

BACKGROUND

Screening for sickle cell traits before marriage or producing children is one of the outstanding preventive measures for sickle cell disease (SCD).The disease is a collection of inherited blood disorders that impact millions globally, with a predominant 75% occurrence in the sub-Saharan region. With increasing burden of SCD on the continent amidst a cost effective prevention method, no study has systematically reviewed or presented meta-analytic uptake or practice of premarital sickle cell trait screening.

METHODS

This review systematically explored the uptake or practice of premarital genotype screening in Africa. We searched PubMed and Scopus databases for African studies on premarital screening for sickle cell traits.

RESULTS

Our results indicate that the pooled uptake of premarital sickle cell trait screening in Africa is 47.82% (95% CI: [46.53-49.11]; I2: 98.95% [98.74-99.13]). Our review observed, a significant relationship between the awareness of sickle cell disease and the uptake of genotype screening; F(1, 13) = 12.04, p = 0.004). The model explained approximately 48.08% of the variation in genotype screening (R² = 0.4808) and predicted a 0.729 increase in the likelihood of genotype screening uptake for every unit rise in sickle cell disease awareness (β = 0.729, p = 0.004). Additionally, Pearson correlation (r = 0.6934) indicated a moderately strong positive correlation between the two variables.

CONCLUSION

With over 75% of the global burden of sickle cell disease domiciled in Africa, the continent cannot overlook the cost of hemoglobinopathies. The uptake of sickle cell traits screening is suboptimal across the continent. To achieve the mandate of sustainable development goal number (3); to end preventable deaths of newborns and children under 5 years of age by 2030, there is need to intensify campaigns on premarital genetic screening through education and other health promotion tools.

The dawn of a cure for sickle cell disease through CRISPR-based treatment: A critical test of equity in public health genomics

Equity in access to genomic technologies, resources, and products remains a great challenge. This was evident especially during the coronavirus disease 2019 (COVID-19) pandemic when the majority of lower middle-income countries were unable to achieve at least 10% population vaccination coverage during initial COVID-19 vaccine rollouts, despite the rapid development of those vaccines. Sickle cell disease (SCD) is an inherited monogenic red blood cell disorder that affects hemoglobin, the protein that carries oxygen through the body. Globally, the African continent carries the highest burden of SCD with at least 240,000 children born each year with the disease. SCD has evolved from a treatable to a curable disease. Recently, the UK medical regulator approved its cure through clustered regularly interspaced short palindromic repeat (CRISPR)-based treatment, whereas the US Food and Drug Administration has equally approved two SCD gene therapies. This presents a remarkable opportunity to demonstrate equity in public health genomics. This CRISPR-based treatment is expensive and therefore, a need for an ambitious action to ensure that they are affordable and accessible where they are needed most and stand to save millions of lives.

Exploring Factors Associated with Quality of Life in Caregivers of Children and Adolescents with Sickle Cell Disease and HIV: A Comparative Analysis

Introduction

Paediatric HIV and sickle cell disease (SCD) are two stigmatising and potentially fatal illnesses that place a significant burden on families. HIV patients benefit from a longstanding free-service national programme in Cameroon, and this could considerably alleviate burden of care on HIV caregivers, possibly leading to better quality of life (QoL) in HIV caregivers compared to SCD caregivers. Our study aimed to compare the QoL between caregivers of children and adolescents with SCD and HIV and explore factors associated with this QoL in Cameroon.

Methods and Materials

We conducted a hospital-based cross-sectional analytic study at Douala Laquintinie Hospital from February to May 2023. A questionnaire was administered to caregivers of paediatric patients (≤18 years) with SCD and HIV. The Pediatrics Quality of Life-Family Impact Module (PedsQL FIM), the 7-item Generalized Anxiety Disorder (GAD-7), and the 9-item Patient Health Question (PHQ-9) tools were used as measures of quality of life, anxiety, and depression, respectively. Multivariable linear regression was used to determine factors associated with quality of life. A significance level was set at p < 0.05.

Results

We included 199 caregivers: SCD = 104 and HIV = 95. The mean age of caregivers in our sample was 40.47 ± 10.18 years. Caregivers of paediatric patients with HIV had a better mean quality of life than SCD (93.01 ± 7.35SD versus 64.86 ± 9.20SD, p < 0.001). PHQ-9 score (B = -1.52, 95% CI = [-2.08; -0.96], p=<0.001), GAD-7 score (B = -1.46, 95% CI = [-2.09; -0.83], p=<0.001), spending less than 75 000 FCFA on medications monthly (B = 12.13, 95% CI = [5.73; 18.94], p=<0.001), and being a SCD caregiver (B = -11.62, 95% CI = [-18.46; -4.78], p=0.001) were factors independently associated with quality of life on multivariable analysis.

Conclusion

Quality of life is lower in caregivers of children and adolescents with SCD than with HIV. Preventing depression and anxiety as well as advocating for the subsidization of medications through a national SCD program may improve quality of life in SCD caregivers.

Self-management needs, strategies and support for sickle cell disease in developing countries: a scoping review protocol

INTRODUCTION

Sickle cell disease (SCD) poses a significant global health burden, particularly affecting individuals in developing countries with constrained healthcare resources. While research on self-management in the context of SCD is emerging, it has predominantly focused on primary studies, and there is a notable dearth of evidence synthesis on SCD self-management in developing countries. This scoping review aims to identify and map self-management needs of individuals living with SCD, the strategies they employed to meet those needs, and the support systems available to them.

METHODS AND ANALYSIS

The review will be conducted following the Arksey and O'Malley's (2005) 29 framework to comprehensively examine the landscape of SCD self-management research. Searches will be performed in PubMed, Scopus, Embase and Dimensions AI, with additional searches in other databases and grey literature. Indexed literature published in English from inception to January 2024 will be included. Reference list from included studies will also be searched manually. Two teams will be constituted to independently screen titles, abstracts and full text against the eligible criteria. Data will be extracted from included studies onto a customised data extraction form.

ETHICS AND DISSEMINATION

Ethical approval is not required for this review due to the fact that it synthesises information from available publications. The findings will be disseminated through publication in a peer-reviewed journal. Also, the findings will possibly be presented at relevant international and national conferences. This protocol has already been registered with the Open Science Framework. The study characteristics such as design and setting will be descriptively analysed and presented as graphs, tables and figures. Thematic analysis will also be conducted based on the study objectives and presented as a narrative summary.

Computing Sickle Erythrocyte Health Index on quantitative phase imaging and machine learning

Sickle cell disease (SCD) is a genetic disorder characterized by abnormal hemoglobin and deformation of red blood cells (RBCs), leading to complications and reduced life expectancy. This study developed an in vitro assessment, the Sickle Erythrocyte Health Index, using quantitative phase imaging (QPI) and machine learning to model the health of RBCs in people with SCD. The health index combines assessment of cell deformation, sickle-shaped classification, and membrane flexibility to evaluate erythrocyte health. Using QPI and image processing, the percentage of sickle-shaped cells and membrane flexibility were quantified. Statistically significant differences were observed between individuals with and without SCD, indicating the impact of underlying pathophysiology on erythrocyte health. Additionally, sodium metabisulfite led to an increase in sickle-shaped cells and a decrease in flexibility in the sickle cell blood samples. Based on these findings, two approaches were used to calculate the Sickle Erythrocyte Health Index: one using hand-crafted features and one using learned features from deep learning models. Both indices showed significant differences between non-SCD and SCD groups and sensitivity to changes induced by sodium metabisulfite. The Sickle Erythrocyte Health Index has important clinical implications for SCD management and could be used by providers when making treatment decisions. Further research is warranted to evaluate the clinical utility and applicability of the Sickle Erythrocyte Health Index in diverse patient populations.

Sickle Cell Disease Update: New Treatments and Challenging Nutritional Interventions

Sickle cell disease (SCD), a distinctive and often overlooked illness in the 21st century, is a congenital blood disorder characterized by considerable phenotypic diversity. It comprises a group of disorders, with sickle cell anemia (SCA) being the most prevalent and serious genotype. Although there have been some systematic reviews of global data, worldwide statistics regarding SCD prevalence, morbidity, and mortality remain scarce. In developed countries with a lower number of sickle cell patients, cutting-edge technologies have led to the development of new treatments. However, in developing settings where sickle cell disease (SCD) is more prevalent, medical management, rather than a cure, still relies on the use of hydroxyurea, blood transfusions, and analgesics. This is a disease that affects red blood cells, consequently affecting most organs in diverse manners. We discuss its etiology and the advent of new technologies, but the aim of this study is to understand the various types of nutrition-related studies involving individuals suffering from SCD, particularly in Africa. The interplay of the environment, food, gut microbiota, along with their respective genomes collectively known as the gut microbiome, and host metabolism is responsible for mediating host metabolic phenotypes and modulating gut microbiota. In addition, it serves the purpose of providing essential nutrients. Moreover, it engages in direct interactions with host homeostasis and the immune system, as well as indirect interactions via metabolites. Nutrition interventions and nutritional care are mechanisms for addressing increased nutrient expenditures and are important aspects of supportive management for patients with SCD. Underprivileged areas in Sub-Saharan Africa should be accompanied by efforts to define and promote of the nutritional aspects of SCD. Their importance is key to maintaining well-being and quality of life, especially because new technologies and products remain limited, while the use of native medicinal plant resources is acknowledged.

High-throughput complement component 4 genomic sequence analysis with C4Investigator

The complement component 4 gene loci, composed of the C4A and C4B genes and located on chromosome 6, encodes for complement component 4 (C4) proteins, a key intermediate in the classical and lectin pathways of the complement system. The complement system is an important modulator of immune system activity and is also involved in the clearance of immune complexes and cellular debris. C4A and C4B gene loci exhibit copy number variation, with each composite gene varying between 0 and 5 copies per haplotype. C4A and C4B genes also vary in size depending on the presence of the human endogenous retrovirus (HERV) in intron 9, denoted by C4(L) for long-form and C4(S) for short-form, which affects expression and is found in both C4A and C4B. Additionally, human blood group antigens Rodgers and Chido are located on the C4 protein, with the Rodger epitope generally found on C4A protein, and the Chido epitope generally found on C4B protein. C4A and C4B copy number variation has been implicated in numerous autoimmune and pathogenic diseases. Despite the central role of C4 in immune function and regulation, high-throughput genomic sequence analysis of C4A and C4B variants has been impeded by the high degree of sequence similarity and complex genetic variation exhibited by these genes. To investigate C4 variation using genomic sequencing data, we have developed a novel bioinformatic pipeline for comprehensive, high-throughput characterization of human C4A and C4B sequences from short-read sequencing data, named C4Investigator. Using paired-end targeted or whole genome sequence data as input, C4Investigator determines the overall gene copy numbers, as well as C4A, C4B, C4(Rodger), C4(Ch), C4(L), and C4(S). Additionally, C4Ivestigator reports the full overall C4A and C4B aligned sequence, enabling nucleotide level analysis. To demonstrate the utility of this workflow we have analyzed C4A and C4B variation in the 1000 Genomes Project Data set, showing that these genes are highly poly-allelic with many variants that have the potential to impact C4 protein function.