Transfusion and sickle cell anemia in Africa

Treating sickle cell disease in resource-limited sub-Saharan Africa: recent strategies and recommendations in addressing the gaps for the provision of evidence-based management

INTRODUCTION

The management of Sickle cell disease (SCD) in sub-Saharan Africa (SSA) suffers from the lack of universal infant and population screening, inadequate access to standard treatment and poor public health prioritization amidst unstable political systems.

AREAS COVERED

The state of evidencebased management of SCD in SSA was investigated including sustainability of international funding agencies.

EXPERT OPINION

Current efforts are fragmentary along languages lines; sometimes driven by the funder's objectives and not the national agenda. The review highlighted the role of internal and external partnerships such as SPARCO, ARISE, CONSA, as well as technology-based support for the implementation of evidence-based care for SCD. We advocate for increased funding to implement SCD comprehensive care in line with the WHO SCD Framework for Primary, Secondary, Tertiary and Specialist Comprehensive Care at state and national level. To achieve this objective, it is important that SCD, as a leading non-communicable disease in Africa, be mandated as a standing agenda for the National Council of Ministers at the African Union, WHO and other regional bodies in Africa.

Osteoarticular Complications of Sickle Cell Disease in Bukavu: A Retrospective Multicenter Cross-Sectional Study

Background and Aim

This study aimed to investigate the epidemiological, clinical, and therapeutic aspects of osteoarticular complications in patients with sickle cell disease in Bukavu.

Methods

We conducted a multicenter cross-sectional study over 5 years, focusing on 31 patients with sickle cell disease who were admitted for osteoarticular complications in Bukavu. Data were collected from medical records and analyzed with the Statistical Package for Social Science 26 (IBM, SPSS 26).

Results

We recorded 31 (6.07%) sickle cell patients with osteoarticular complications, with a mean age of 10.5 ± 5.6 years (extremes: 2-30 years). Pain, fever, and functional impotence were the most frequent reasons for consultation with 9 (29.03%) patients. Septic arthritis was the most common complication in 10 (32.26%), followed by osteonecrosis of the femoral head in 8 (25.81%), chronic osteomyelitis in 7 (22.58%) cases, and acute osteomyelitis in 4 (12.70%) patients. The femur was the most affected bone. Articular complications predominantly impacted larger joints, with the knee joint experiencing the highest rate of damage, occurring in 38.71% of cases. Treatment, including medical and surgical methods, was provided in 16 cases (51.6%). Complete healing without residual effects was achieved in 22 patients (70.96%).

Conclusion

The osteoarticular complications of sickle cell disease are frequent in the city of Bukavu, and regular monitoring and early consultation would enable early diagnosis and management.

Evolving Landscape of Sickle Cell Anemia Management in Africa: A Critical Review

Sickle cell disease (SCD) is a prevalent inherited blood disorder, particularly affecting populations in Africa. This review examined the disease's burden, its diverse clinical presentations, and the challenges associated with its management in African settings. Africa bears a significant burden of SCD, with prevalence varying across countries and age groups. Newborn screening programs have highlighted the high prevalence of SCD at birth, emphasizing the need for early diagnosis and intervention. The clinical manifestations of SCD in Africa are multifaceted, encompassing acute complications like vaso-occlusive crises, acute chest syndrome, and stroke, as well as chronic complications such as organ damage and leg ulcers. Biological factors, including fetal hemoglobin levels, and demographic factors, like age and sex, influence disease severity and outcomes. The management of SCD in Africa faces numerous challenges. Limited access to resources, including diagnostic tools, medications, and trained healthcare professionals, hinders optimal care. The high cost of advanced therapies further restricts patient access. Cultural stigma and a lack of awareness create additional barriers to effective management. To address these challenges, early diagnosis through newborn screening programs and point-of-care testing is crucial. Comprehensive care models, including hydroxyurea therapy, pain management, and patient education, are essential for improving outcomes. Collaboration with international networks and leveraging local resources can enhance the sustainability of SCD programs. In conclusion, SCD significantly impacts African populations. Overcoming the challenges associated with its management requires addressing resource limitations, affordability issues, and cultural barriers. Early diagnosis, comprehensive care models, and ongoing research focused on affordability and accessibility are crucial for improving the lives of individuals living with SCD in Africa.

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.

Knowledge and Attitudes of Blood Donors Toward Sickle Cell Anemia in Ibadan

Background Sickle cell anemia (SCA) is a common condition of public health concern in Nigeria. Different therapeutic approaches have been developed to manage SCA, including blood transfusion. In a bid to develop a sustainable solution to the blood supply pool, the SmileBuilders Initiative organizes a blood donation drive (Donate-A-Pint Project) quarterly in Ibadan, Nigeria. This study aimed to assess the awareness, knowledge, and attitudes of blood donors in Ibadan, Nigeria, towards SCA. Methods A descriptive cross-sectional study was conducted at the University College Hospital Blood Bank in Ibadan over a period of three months. A validated questionnaire, based on similar studies in Nigeria, was used to collect data from blood donors. The SPSS version 23 was used for data analysis, and the chi-square test of independence assessed associations between variables, with a significance level of 0.05. Results Among 205 donors, 68.8% were male, and 42.4% were in the age category of ≥25 years. Most donors (60.0%) were university students. While 12.3% had never heard of SCA, 79.5% were aware of their genotype. Regarding the intrauterine diagnosis of hemoglobin SS (HbSS), 20.0% would allow pregnancy, 31.7% would abort, and 48.3% were undecided. Most respondents (73.2%) had good knowledge of SCA (mean score = 7.0/10.0). If partners were found to have SCA after marriage, 42.9% were undecided. Knowledge of SCA was significantly associated with sex (p = 0.017) and education level (p = 0.001). Conclusion Blood donors in Ibadan have good knowledge, awareness, and attitudes toward SCA. However, more health education would benefit the population.

Attitude and Behavior of Parents of Children With Sickle Cell Disease Toward the Disease: An Observational Study in Saudi Arabia

BACKGROUND

Sickle cell disease (SCD) is a significant hematological disorder affecting populations worldwide, with a notable prevalence in certain regions of Saudi Arabia. Despite extensive screening programs, there is a critical need for improved public health education to enhance understanding and management of SCD. This study examines the relationship between the attitudes and behaviors of parents toward their children's disease and its management.

METHODS

We conducted a cross-sectional observational study at the King Fahd Medical Research Center in Jeddah. This research encompassed children aged 5-16 years with SCD and their parents. Comprehensive questionnaires assessed sociodemographic data, attitudes toward SCD, and behavioral responses to the illness and treatment.

RESULTS

The study included 66 parents, predominantly in the age range of 30-39 years and earning below 5000 Saudi Riyals, who exhibited varying attitudes towards SCD, with a majority questioning the availability of a cure and expressing caution towards new treatments. Despite a cautious approach to invasive treatments, parents relied on information from healthcare providers. Attitudes towards treatment showed significant differences based on gender and education level, with females and less-educated parents exhibiting more hesitancy towards new treatment and blood transfusions.

CONCLUSION

The study indicates that while parents show a positive and proactive attitude toward SCD, there is hesitancy towards new and invasive treatments, reflecting the need for continued educational support. The results underscore the importance of tailored healthcare communication strategies to address the diverse needs of families affected by SCD.

Comparison of in-hospital mortality in children and adolescents with sickle cell disease in a resource-limited setting before and during the COVID-19 pandemic

BACKGROUND

COVID-19 in children and adolescents with sickle cell disease (SCD) has variable presentations (from mild to severe disease), and the main symptoms are vaso-occlusive crises (VOC) and acute chest syndrome (ACS). We hypothesized that the desertion of hospitals due to the pandemic would lead to late arrival at the emergency room and an increased mortality. In this study, we sought to measure and compare the mortality of children with sickle cell disease before and during the COVID-19 pandemic.

MATERIAL AND METHODS

We conducted a retrospective cohort study at the sickle cell disease management center of Laquintinie Hospital in Douala (Cameroon). The study period was divided into two, i.e., from March 2019 to February 2020 (Pre-COVID-19) and from March 2020 to February 2021 (COVID-19). All administrative and ethical considerations were fully respected. Data were analyzed using SPSS 20.0.

RESULTS

Overall, 823 patients were admitted during the study period. Males represented 52.4% of the overall population, giving a sex ratio of 1.1:1. We admitted 479 patients during the pre-COVID-19 period versus 344 patients during the COVID-19 period, which is a 28.2% drop in admissions during the COVID-19 period. The mortality rate was 3.5% during the pre-COVID-19 period and 3.2% during the COVID-19 period (p>0.05). The most common causes of death were ACS (39.3%, n = 11), severe anemia (25.0%, n = 7), and VOC (17.9%, n = 5). ACS (adjusted odds ratio [aOR]=3.628, 95% confidence interval [CI], [1.645-7.005], p<0.001) was significantly associated with mortality.

CONCLUSION

During the COVID-19 pandemic, although the consultation frequency decreased, the mortality rate of sickle cell disease patients remained unchanged.

Defining global strategies to improve outcomes in sickle cell disease: a Lancet Haematology Commission

All over the world, people with sickle cell disease (an inherited condition) have premature deaths and preventable severe chronic complications, which considerably affect their quality of life, career progression, and financial status. In addition, these people are often affected by stigmatisation or structural racism, which can contribute to stress and poor mental health. Inequalities affecting people with sickle cell disease are also reflected in the distribution of the disease—mainly in sub-Saharan Africa, India, and the Caribbean—whereas interventions, clinical trials, and funding are mostly available in North America, Europe, and the Middle East. Although some of these characteristics also affect people with other genetic diseases, the fate of people with sickle cell disease seems to be particularly unfair. Simple, effective interventions to reduce the mortality and morbidity associated with sickle cell disease are available. The main obstacle preventing better outcomes in this condition, which is a neglected disease, is associated with inequalities impacting the patient populations. The aim of this Commission is to highlight the problems associated with sickle cell disease and to identify achievable goals to improve outcomes both in the short and long term.

The ambition for the management of people with sickle cell disease is that curative treatments become available to every person with the condition. Although this would have seemed unrealistic a decade ago, developments in gene therapy make this potentially achievable, albeit in the distant future. Until these curative technologies are fully developed and become widely available, health-care professionals (with the support of policy makers, funders, etc) should make sure that a minimum standard of care (including screening, prophylaxis against infection, acute medical care, safe blood transfusion, and hydroxyurea) is available to all patients.

In considering what needs to be achieved to reduce the global burden of sickle cell disease and improve the quality of life of patients, this Commission focuses on five key areas: the epidemiology of sickle cell disease (Section 1 ); screening and prevention (Section 2 ); established and emerging treatments for the management of the disease (Section 3 ); cellular therapies with curative potential (Section 4 ); and training and education needs (Section 5 ). As clinicians, researchers, and patients, our objective to reduce the global burden of sickle cell disease aligns with wider public health aims to reduce inequalities, improve health for all, and develop personalised treatment options. We have observed in the past few years some long-awaited momentum following the development of innovative point-of-care testing devices, new approved drugs, and emerging curative options. Reducing the burden of sickle cell disease will require substantial financial and political commitment, but it will impact the lives of millions of patients and families worldwide and the lessons learned in achieving this goal would unarguably benefit society as a whole.

Hydroxyurea treatment for adult sickle cell anemia patients in Kinshasa

Background: Despite a high incidence of sickle cell anemia, hydroxyurea (HU) treatment is rarely used in the DR Congo. This study aims to assess the efficacy of HU, the incidence of side effects that may limit its use in adults and to determine the dose needed for clinical improvement in patients. Methods: In a prospective study, patients received an initial dose of 15 mg/kg/day which was increased by 5 mg/kg every 6 months, up to a maximum of 30 mg/kg/day. The response and side effects to HU were evaluated biologically and clinically every 3 months during a 2-year period. Results: Seventy adult patients with a moderate or severe clinical phenotype initiated treatment. Only minor side effects were reported. At the end of the 2-year treatment phase, 45 (64.3%) had dropped out, of whom 33 were without a clear reason. Clinical and biological improvement was more marked during the first year. There was a reduction in severe vaso-occlusive crises (p < 0.001), need for transfusion (p < 0.001), and hospitalization days (p = 0.038). Fetal hemoglobin (HbF) levels increased on average 2.9 times after 12 months (p < 0.001). The increase in mean corpuscular volume was greater in the first year (p < 0.001) than in the second year (p = 0.041). The decrease in leukocytes (p < 0.001) was significant during the first year. In 70% of patients, the 20 mg/kg/day dose was needed to reach the 20% HbF threshold. Conclusion: HU is effective and well tolerated. The magnitude of the response varies from one patient to another. Improvement of clinical manifestations is achieved in most patients with a relatively low dose. Effective implementation of HU treatment will require improved adherence to treatment.

Red blood cell alloantibodies in paediatric transfusion in sub-Saharan Africa: A new cohort and literature review

Blood transfusion support predisposes transfused children to the risk of erythrocyte alloimmunization in Sub-Saharan Africa. A cohort of 100 children receiving one to five blood transfusions were recruited for screening and identification of irregular antibodies using gel filtration technique. The mean age was 8 years and the sex-ratio at 1.2. The retrieved pathologies were: major sickle cell anaemia (46%), severe malaria (20%), haemolytic anaemia (4%), severe acute malnutrition (6%), acute gastroenteritis (5%), chronic infectious syndrome (12%) and congenital heart disease (7%). The children presented with haemoglobin levels ≤6 g/dl, and 16% of them presented positive irregular antibodies directed against the Rhesus (30.76%) and Kell (69.24%) blood group systems. A literature review shows that irregular antibody screenings vary from 17% to 30% of transfused paediatric patients in Sub-Saharan Africa. These alloantibodies are in particular directed against the Rhesus, Kell, Duffy, Kidd and MNS blood group and generally found in sickle cell disease and malaria. This study highlights the urgent need of extended red blood cell phenotyping including typing for C/c, E/e, K/k, and Fya/Fyb, and if possible Jka/Jkb, M/N, and S/s for children before transfusion in Sub-Saharan Africa.

Recent progress in the treatment of sickle cell disease: an up-to-date review

Background

Sickle cell disease is a fatal systemic condition characterized by acute painful episodes, persistent anemia, ongoing organ damage, organ infarction, and a markedly shorter average lifetime. It first appeared in the tropics' malarial zones, where carriers benefit from an evolutionary advantage by being shielded from malaria death. Due to demographic shifts, this crisis now affects people all over the world. In higher-income areas, such as vast swaths of Europe and North and South America, more children are born with the syndrome.

Main body

Over the last 10 years, a clearer knowledge of the change from fetal to adult hemoglobin has evolved. Further investigation into chimerism, genomics, mixed gene editing, and therapeutic reactivation of fetal hemoglobin has produced very promising findings. Between 2017 and 2019, three innovative medications for sickle cell disease were approved by the FDA thanks to previous advances, while many more treatments are now under development.

Short conclusion

To improve patient outcomes, various innovative medications that were created in the late 1990s and utilized to treat sickle cell disease are examined in this study. In our appraisal, we'll also focus on the most important developments of the decade.

Alloimmunisation against red blood cells in sickle cell disease: transfusion challenges in high-income and low-income countries

Sickle cell disease is the most frequent inherited disorder in sub-Saharan Africa and in many high-income countries (HICs). Transfusion is a key element of treatment, but it results in high rates of alloimmunisation against red blood cell antigens and post-transfusion haemolysis, which can be life-threatening in severe cases. The prevention of alloimmunisation is, therefore, an important issue in both HICs and in low-income countries (LICs). In HICs, the main reason for high alloimmunisation rates is blood group disparity between blood donors, who are mostly of European descent, and the patients, who are mostly of African descent. However, alloimmunisation rates also remain high in sub-Saharan Africa despite the homogeneity of blood group antigen frequencies between donors and patients; this occurrence is probably due to matching strategies limited to ABO blood group and RhD. However, other possible underlying causes of alloimmunisation have also been suggested, with each cause affecting HICs and LICs in different ways-eg, the immunogenetic and inflammatory status of the patient and the characteristics of the red blood cell products. In this Viewpoint, we discuss the available data and hypotheses that potentially account for the association of sickle cell disease with high rates of alloimmunisation in both settings, HICs and LICs (focusing particularly on sub-Saharan Africa), and the challenges faced by HICs and LICs to improve prevention of alloimmunisation.

Low-cost molecular methodology for blood group antigens identification and genotyping contribution to transfusion efficacy in multiple transfused patients

BACKGROUND

Blood transfusions usually result in the production of alloantibodies, complicating subsequent transfusions. Many blood group systems, in addition to ABO and Rh, can lead to the production of irregular antibodies in multiple transfused patients.

OBJECTIVES

The aim of this work was to standardize a molecular biology methodology for identified some alleles of KEL, FY, JK and DI blood group system; the transfusion efficacy of chronically transfused patients with phenotype-matched blood was also evaluated.

METHODS

A PCR-SSP was developed and validated using Sanger sequencing. The genotype and frequencies of 141 multiple transfused patients treated at blood banks of Maringá were compared with the blood donor's population to assess the availability of compatible blood bags. The clinical history of 29 patients on a phenotype-compatible transfusion regimen was followed to assess pre- and post-genotyping alloimmunization.

RESULTS

The PCR-SSP was effective in identifying the genotypes under study. Significant differences were observed in genotype and allele frequencies for FY and JK. Compatible bags were identified for all patients. Most patients (93.1%) did not develop new alloantibodies after erythrocyte genotyping.

CONCLUSION

Erythrocyte genotyping proved to be important both in the search for positive blood bags for rare alleles and in the prevention of alloimmunization.

Homozygous sickle cell disease related mortality in Senegal (2011-2020)

Homozygous sickle cell disease (HSCD) is characterized by multiorgan morbidity and an increased risk of early death. We aim to describe the mortality rate, causes, and risk factors of death in HSCD between 2011 and 2020. We conducted a retrospective study with a duration of 10 years in the cohort of 2348 HSCD patients. The mortality rate was determined by reporting the number of deaths to the total number of patients followed in the year. Sociodemographic, clinical, biological data and causes of death were studied. Death risk factors were determined by a bivariate analysis comparing deceased and living HSCD patients. The mean age of death was 26 years (3-52). The sex ratio was 1.2. The mortality rate was 2.76%. The death rate was high in 2011 (3.2%) and low in 2020 (0.17%). We observed a significant reduction of mortality of 94.6%. Most of the common causes of death were acute anemia (40%), acute chest syndrome (24.6%), and infections (20%). Risk factors of death were age, vaso-occlusive crises ≥3, acute chest syndrome, blood transfusion, and chronic complications. Mortality among HSCD has significantly decreased over the past 10 years in Senegal, and the main causes of death were acute anemia, acute chest syndrome, and infections.

Sickle cell disease in sub-Saharan Africa: transferable strategies for prevention and care

Sickle cell disease can be life-threatening or chronically debilitating for both children and adults. Worldwide, more than 300 000 children are born with sickle cell disease every year, over 75% of whom in sub-Saharan Africa. Increased awareness and early interventions, such as neonate screening and comprehensive care, have led to considerable reductions in mortality in children younger than 5 years in high-income countries. However, sickle cell disease prevention and care have largely been neglected in Africa. Without intervention, 50-90% of affected children in many sub-Saharan African countries die before their fifth birthday. Fortunately, increasing initiatives in sub-Saharan Africa are piloting interventions such as neonate screening and comprehensive care, and as mortality declines, quality of life and increased life expectancy become major targets for interventions. Hydroxyurea (hydroxycarbamide) and haematopoietic stem-cell transplantation have already been shown to be effective therapies in high-income countries, but are either not widely accessible or too expensive for most African populations. These challenges are being alleviated by numerous networks evolving through international collaborations that are positively changing the outlook of sickle cell disease management in sub-Saharan Africa. In this Series paper, we describe the epidemiology, pathophysiology, clinicobiological profile, and psychosocial effects of sickle cell disease in sub-Saharan Africa. We highlight transferable strategies already used for the successful management of the condition and key strategies and recommendations for affordable and comprehensive care on the continent. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Screening for new red blood cell alloantibodies after transfusion in patients with sickle cell disease

BACKGROUND

Patients with sickle cell disease (SCD) are frequent recipients of red blood cell (RBC) transfusions and are at risk for RBC alloimmunization. RBC alloimmunization is diagnosed by identifying RBC alloantibodies as part of pre-transfusion testing, but this testing fails to detect alloantibodies that have evanesced. It may be beneficial to screen for new RBC alloantibody development after transfusion before possible antibody evanescence.

STUDY DESIGN AND METHODS

Our institution started a new initiative for episodically transfused patients with SCD to obtain at least one antibody screen 2-6 months after transfusion as part of their clinical care. A database was created to prospectively track all transfused patients for 1 year and their post-transfusion antibody screen results. Patients received prophylactically CEK-matched RBC units.

RESULTS

During the study year, 138 patients with SCD received a total of 242 RBC transfusions. Patients with a history of an RBC alloantibody (n = 13, 9.4%) had previously received more RBC units than non alloimmunized patients (median 11 vs. 2 RBC units, p = .0002). A total of 337 post-transfusion antibody screens were obtained in 127 patients (92.0%) with 110 patients (79.7%) having at least one antibody screen 2-6 months post-transfusion. With this prospective testing, two new RBC alloantibodies (anti-C and -M) were identified in two patients.

CONCLUSION

It is feasible to test for new RBC alloantibody development in most episodically transfused patients with SCD as part of their routine care. The yield of this screening appears low with CEK matching, but it could still provide important information for individual patients.