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1.
Hum Mol Genet ; 33(10): 919-929, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38339995

RESUMO

The clinical severity of sickle cell disease (SCD) is strongly influenced by the level of fetal haemoglobin (HbF) persistent in each patient. Three major HbF loci (BCL11A, HBS1L-MYB, and Xmn1-HBG2) have been reported, but a considerable hidden heritability remains. We conducted a genome-wide association study for HbF levels in 1006 Nigerian patients with SCD (HbSS/HbSß0), followed by a replication and meta-analysis exercise in four independent SCD cohorts (3,582 patients). To dissect association signals at the major loci, we performed stepwise conditional and haplotype association analyses and included public functional annotation datasets. Association signals were detected for BCL11A (lead SNP rs6706648, ß = -0.39, P = 4.96 × 10-34) and HBS1L-MYB (lead SNP rs61028892, ß = 0.73, P = 1.18 × 10-9), whereas the variant allele for Xmn1-HBG2 was found to be very rare. In addition, we detected three putative new trait-associated regions. Genetically, dissecting the two major loci BCL11A and HBS1L-MYB, we defined trait-increasing haplotypes (P < 0.0001) containing so far unidentified causal variants. At BCL11A, in addition to a haplotype harbouring the putative functional variant rs1427407-'T', we identified a second haplotype, tagged by the rs7565301-'A' allele, where a yet-to-be-discovered causal DNA variant may reside. Similarly, at HBS1L-MYB, one HbF-increasing haplotype contains the likely functional small indel rs66650371, and a second tagged by rs61028892-'C' is likely to harbour a presently unknown functional allele. Together, variants at BCL11A and HBS1L-MYB SNPs explained 24.1% of the trait variance. Our findings provide a path for further investigation of the causes of variable fetal haemoglobin persistence in sickle cell disease.


Assuntos
Anemia Falciforme , Proteínas de Ligação ao GTP , Estudo de Associação Genômica Ampla , Haplótipos , Feminino , Humanos , Masculino , Alelos , Anemia Falciforme/genética , Anemia Falciforme/sangue , Predisposição Genética para Doença , Nigéria , Proteínas Nucleares/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas Repressoras/genética
2.
Gene Ther ; 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38012299

RESUMO

Somatic gene therapy will be one of the most exciting practices of genetic medicine in Africa and is primed to offer a "new life" for persons living with sickle cell disease (SCD). Recently, successful gene therapy trials for SCD in the USA have sparked a ray of hope within the SCD community in Africa. However, the high cost, estimated to exceed 1.5 million USD, continues to be a major concern for many stakeholders. While affordability is a key global health equity consideration, it is equally important to reflect on other ethical, legal and social issues (ELSIs) that may impact the responsible implementation of gene therapy for SCD in Africa. These include informed consent comprehension, risk of therapeutic misestimation and optimistic bias; priorities for SCD therapy trials; dearth of ethical and regulatory oversight for gene therapy in many African countries; identifying a favourable risk-benefit ratio; criteria for the selection of trial participants; decisional conflict in consent; standards of care; bounded justice; and genetic tourism. Given these ELSIs, we suggest that researchers, pharma, funders, global health agencies, ethics committees, science councils and SCD patient support/advocacy groups should work together to co-develop: (1) patient-centric governance for gene therapy in Africa, (2) public engagement and education materials, and (3) decision making toolkits for trial participants. It is also critical to establish harmonised ethical and regulatory frameworks for gene therapy in Africa, and for global health agencies to accelerate access to basic care for SCD in Africa, while simultaneously strengthening capacity for gene therapy.

3.
Pediatr Blood Cancer ; 68(6): e28969, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33788390

RESUMO

BACKGROUND: Although effectiveness of hydroxyurea (HU) in sickle cell disease is well established, unanswered questions persist about its use in African children. We determined real-life issues of acceptability, availability, and monitoring of HU use in Nigeria. METHODS: A retrospective longitudinal review of laboratory data of patients on HU was done from case files, followed by a cross-sectional survey that captured families' perception of medication and clinic adherence, laboratory tests, benefits, side effects, and acceptability. RESULTS: One hundred sixteen patients (1.2-17 years) received HU (mean ± SD = 18.5 ± 4.3 mg/kg/day) in 33 months. Eighty-nine had laboratory analysis. Dose escalation was the initial goal, but only 80% of patients had some form of it. Parents reported improvement in general well-being and reduction in bone pain episodes, hospital admissions, and blood transfusion. While most parents (89.5%) reported satisfaction with HU, 61% reported dissatisfaction with daily drug use, and the frequency and cost of monitoring. Sixteen percent voluntarily stopped therapy. Adherence to daily HU was 88.8%, doctor's appointments 24.5%, hematology tests 18.9%, and organ function tests 37.4%. There were no significant toxicities. Significant increases in hemoglobin, hemoglobin F and mean corpuscular volume, and reduction in absolute neutrophil count occurred despite inconsistent dose escalation. CONCLUSION: HU (10-15 mg/kg/day starting dose) is safe and seems effective and acceptable to parents. Parental commitment to therapy, pre-HU education (that continues during therapy), provision of affordable HU, and subsidized laboratory tests are important considerations for initiating therapy. Special HU clinics may facilitate dose escalation and reduce frequency of monitoring. Studies are needed on feasibility of maximum tolerable dose HU protocols in sub-Saharan Africa without compromising safety.


Assuntos
Anemia Falciforme/tratamento farmacológico , Antidrepanocíticos/uso terapêutico , Hidroxiureia/uso terapêutico , Cooperação do Paciente/estatística & dados numéricos , Satisfação do Paciente/estatística & dados numéricos , Adolescente , Antidrepanocíticos/efeitos adversos , Criança , Pré-Escolar , Estudos Transversais , Feminino , Hemoglobina Fetal/análise , Hemoglobina Falciforme/análise , Humanos , Hidroxiureia/efeitos adversos , Lactente , Estudos Longitudinais , Masculino , Nigéria , Pais/psicologia , Estudos Retrospectivos
4.
BMC Pregnancy Childbirth ; 21(1): 498, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34238241

RESUMO

BACKGROUND: Haemoglobin genotype screening at prenatal care offers women an opportunity to be aware of their genotype, receive education on sickle cell disease (SCD) and may increase maternal demand for SCD newborn screening. In developed countries, most pregnant women who access prenatal care and deliver at the hospital receive haemoglobin genotype screening. In settings with low prenatal care attendance and low hospital deliveries, community-based screening may provide similar opportunity for pregnant women. We assessed the feasibility and acceptability of integrating haemoglobin genotype screening into an existing community-based HIV program. METHODS: Onsite community-based integrated testing for HIV, hepatitis B virus and haemoglobin electrophoresis, were conducted for pregnant women and their male partners. Community Health Advisors implementing the NIH and PEPFAR-supported Healthy Beginning Initiative (HBI) program provided education on SCD, collected blood sample for haemoglobin electrophoresis and provided test results to participants enrolled into the HBI program. We concurrently conducted a cross-sectional study using a pretested, semi-structured, interviewer administered questionnaire to collect demographic data and assess awareness of individual haemoglobin "genotype" among HBI pregnant women participants. RESULTS: In this study, 99.9% (10,167/10,168) of pregnant women who received education on SCD accepted and completed the survey, had blood drawn for haemoglobin electrophoresis and received their results. A majority of participating pregnant women (97.0%) were not aware of their haemoglobin "genotype". Among the participants who were incorrect about their haemoglobin "genotype", 41.1% (23/56) of women who reported their haemoglobin "genotype" as AA were actually AS. The odds of haemoglobin "genotype" awareness was higher among participants who were in younger age group, completed tertiary education, had less number of pregnancies, and attended antenatal care. Overall prevalence of sickle cell trait (AS) was 18.7%. CONCLUSIONS: It is feasible to integrate haemoglobin "genotype" testing into an existing community-based maternal-child program. Most pregnant women who were unaware of their haemoglobin "genotype" accepted and had haemoglobin genotype testing, and received their test results. Increasing parental awareness of their own haemoglobin "genotype" could increase their likelihood of accepting newborn screening for SCD.


Assuntos
Programas Gente Saudável , Hemoglobina Falciforme/análise , Programas de Rastreamento/métodos , Cuidado Pré-Natal/métodos , Traço Falciforme/diagnóstico , Adulto , Anemia Falciforme/genética , Estudos Transversais , Estudos de Viabilidade , Feminino , Implementação de Plano de Saúde , Nível de Saúde , Testes Hematológicos , Humanos , Recém-Nascido , Masculino , Triagem Neonatal , Nigéria , Gravidez , Prevalência , Avaliação de Programas e Projetos de Saúde , Parceiros Sexuais , Traço Falciforme/epidemiologia , Traço Falciforme/genética
5.
Global Health ; 17(1): 20, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33596947

RESUMO

BACKGROUND: The burden of sickle cell disease (SCD) is greatest among African nations. Effective scalability of evidence-based interventions (e.g., newborn screening, health education, prophylaxis for infection, optimal nutrition and hydration, hydroxyurea therapy, blood transfusions, and transcranial Doppler (TCD) screening) is urgently needed particularly in these settings for disease management. However, Africa is constrained by limited resources and the lack of capacity to conduct implementation science research for proper understanding of context, and assessment of barriers and facilitators to the uptake and scalability of evidence-based interventions (EBI) for SCD management. MAIN BODY: We outline implementation science approaches to embed EBI for SCD within the African context and highlight key implementation research programs for SCD management. Building implementation research capacity will meet the major need of developing effective life-long and accessible locally-tailored interventions for patients with SCD in Africa. CONCLUSION: This commentary communicates the importance of the application of implementation science methodology to scale-up evidence-based interventions for the management of SCD in order to reduce pain, prevent other morbidities and premature death experienced by people with SCD in Africa, and improve their overall quality of life.


Assuntos
Anemia Falciforme , Ciência da Implementação , África , Anemia Falciforme/terapia , Medicina Baseada em Evidências , Humanos , Qualidade de Vida
6.
Hemoglobin ; 45(3): 163-170, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34355623

RESUMO

Sickle cell disease is a genetic disease with a predisposition to infections caused by encapsulated organisms, especially Streptococcus pneumoniae. Pneumococcal vaccines and prophylactic penicillin have reduced the rate of this infection and mortality in sickle cell disease. However, implementation of these interventions is limited in Africa. The objectives of the study were to assess health care providers' behaviors with the implementation of pneumococcal vaccination and penicillin prophylaxis and to identify barriers to their use. A 25-item online questionnaire was administered through SickleinAfrica: a network of researchers, and healthcare providers, in Ghana, Nigeria, and Tanzania, working to improve health outcomes of sickle cell disease in Africa. Data was collected and managed using the Research Electronic Data Capture (REDCap), tools and data analysis was done using STATA version 13 and R statistical software. Eighty-two medical practitioners responded to the questionnaire. Only 54.0 and 48.7% of respondents indicated the availability of published guidelines on sickle cell disease management and pneumococcal vaccine use, respectively, at their facilities. The majority (54.0%) perceived that the vaccines are effective but over 20.0% were uncertain of their usefulness. All respondents from Ghana and Tanzania affirmed the availability of guidelines for penicillin prophylaxis in contrast to 44.1% in Nigeria. Eighty-five percent of respondents affirmed the need for penicillin prophylaxis but 15.0% had a contrary opinion for reasons including the rarity of isolation of Streptococcus pneumoniae in African studies, and therefore, the uncertainty of its benefit. Lack of published guidelines on the management of sickle cell disease and doubts about the necessity of prophylactic measures are potential barriers to the implementation of effective interventions.


Assuntos
Anemia Falciforme , Penicilinas , Infecções Pneumocócicas , Vacinas Pneumocócicas/uso terapêutico , Anemia Falciforme/complicações , Pessoal de Saúde , Humanos , Nigéria , Penicilinas/uso terapêutico , Infecções Pneumocócicas/tratamento farmacológico , Infecções Pneumocócicas/etiologia , Infecções Pneumocócicas/prevenção & controle , Streptococcus pneumoniae
7.
BMC Med ; 18(1): 92, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32340612

RESUMO

BACKGROUND: Most of the world's sickle cell disease (SCD) burden is in Africa, where it is a major contributor to child morbidity and mortality. Despite the low cost of many preventive SCD interventions, insufficient resources have been allocated, and progress in alleviating the SCD burden has lagged behind other public-health efforts in Africa. The recent announcement of massive new funding for research into curative SCD therapies is encouraging in the long term, but over the next few decades, it is unlikely to help Africa's SCD children substantially. MAIN DISCUSSION: A major barrier to progress has been the absence of large-scale early-life screening. Most SCD deaths in Africa probably occur before cases are even diagnosed. In the last few years, novel inexpensive SCD point-of-care test kits have become widely available and have been deployed successfully in African field settings. These kits could potentially enable universal early SCD screening. Other recent developments are the expansion of the pneumococcal conjugate vaccine towards near-universal coverage, and the demonstrated safety, efficacy, and increasing availability and affordability of hydroxyurea across the continent. Most elements of standard healthcare for SCD children that are already proven to work in the West, could and should now be implemented at scale in Africa. National and continental SCD research and care networks in Africa have also made substantial progress, assembling care guidelines and enabling the deployment and scale-up of SCD public-health systems. Substantial logistical, cultural, and awareness barriers remain, but with sufficient financial and political will, similar barriers have already been overcome in efforts to control other diseases in Africa. CONCLUSION AND RECOMMENDATIONS: Despite remaining challenges, several high-SCD-burden African countries have the political will and infrastructure for the rapid implementation and scale-up of comprehensive SCD childcare programs. A globally funded effort starting with these countries and expanding elsewhere in Africa and to other high-burden countries, including India, could transform the lives of SCD children worldwide and help countries to attain their Sustainable Development Goals. This endeavor would also require ongoing research focused on the unique needs and challenges of SCD patients, and children in particular, in regions of high prevalence.


Assuntos
Anemia Falciforme/terapia , África , Pré-Escolar , Feminino , Humanos , Lactente , Masculino
8.
Blood Cells Mol Dis ; 84: 102438, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32504882

RESUMO

BACKGROUND/OBJECTIVE: Sickle cell disease (SCD) is a monogenic disease with multiple phenotypic expressions. Previous studies describing SCD clinical phenotypes in Nigeria were localized, with limited data, hence the need to understand how SCD varies across Nigeria. METHOD: The Sickle Pan African Research Consortium (SPARCO) with a hub in Tanzania and collaborative sites in Tanzania, Ghana and Nigeria, is establishing a single patient-consented electronic database with a target of 13,000 SCD patients. In collaboration with the Sickle Cell Support Society of Nigeria, 20 hospitals, with paediatric and adult SCD clinics, are participating in patient recruitment. Demographic and clinical information, collected with uniform case report forms, were entered into Excel spreadsheets and uploaded into Research Electronic Data Capture software by trained data clerks and frequency tables generated. RESULT: Data were available on 3622 patients enrolled in the database, comprising 1889 (52.9%) females and 1434 (39.6%) children ≤15 years. The frequencies of Hb SS, Hb SC and Hb Sß thalassemia in this data set were 97.5%, 2.5% and 0% respectively. Sixty percent, 23.8%, 5.9%, 4.8% and 2.5% have had bone pain crisis, dactylitis, acute chest syndrome, priapism and stroke respectively. The most frequent chronic complications were: leg ulcers (6.5%), avascular necrosis of bone (6.0%), renal (6.3%) and pulmonary hypertension (1.1%). Only 13.2% had been hospitalized while 67.5% had received blood transfusion. CONCLUSION: These data on the spectrum of clinical phenotypes of SCD are useful for planning, improving the management of SCD across Nigeria and provide a foundation for genomic research on SCD.


Assuntos
Anemia Falciforme/complicações , Síndrome Torácica Aguda/etiologia , Adolescente , Adulto , Anemia/etiologia , Anemia Falciforme/epidemiologia , Criança , Feminino , Humanos , Úlcera da Perna/etiologia , Masculino , Nigéria/epidemiologia , Dor/etiologia , Acidente Vascular Cerebral/etiologia , Adulto Jovem
9.
Blood Cells Mol Dis ; 78: 22-28, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30773433

RESUMO

BACKGROUND: Sickle cell disease (SCD) is a neglected burden of growing importance. >312,000 births are affected annually by sickle cell anaemia (SCA). Early interventions such as newborn screening, penicillin prophylaxis and hydroxyurea can substantially reduce the mortality and morbidity associated with SCD. Nevertheless, their implementation in African countries has been mostly limited to pilot projects. Recent development of low-cost point-of-care testing (POCT) devices for sickle haemoglobin (HbS) could greatly facilitate the diagnosis of those affected. METHODS: We conducted the first multi-centre, real-world assessment of a low-cost POCT device, HemoTypeSC, in a low-income country. Between September and November 2017, we screened 1121 babies using both HemoTypeSC and HPLC and confirmed discordant samples by molecular diagnosis. FINDINGS: We found that, in optimal field conditions, the sensitivity and specificity of the test for SCA were 93.4% and 99.9%, respectively. All 14 carriers of haemoglobin C were successfully identified. Our study reveals an overall accuracy of 99.1%, but also highlights the importance of rigorous data collection, staff training and accurate confirmatory testing. It suggests that HPLC results might not be as reliable in a resource-poor setting as usually considered. INTERPRETATION: The use of such a POCT device can be scaled up and routinely used across multiple healthcare centres in sub-Saharan Africa, which would offer great potential for the identification and management of vast numbers of individuals affected by SCD who are currently undiagnosed. FUNDING US: Imperial College London's Wellcome Trust Centre for Global Health Research (grant #WMNP P43370).


Assuntos
Anemia Falciforme/sangue , Anemia Falciforme/diagnóstico , Testes Hematológicos , Testes Imediatos , Alelos , Anemia Falciforme/genética , Pré-Escolar , Feminino , Frequência do Gene , Genótipo , Testes Hematológicos/economia , Testes Hematológicos/métodos , Humanos , Lactente , Recém-Nascido , Masculino , Triagem Neonatal , Testes Imediatos/economia , Testes Imediatos/normas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Globinas beta/genética , Globinas beta/metabolismo
11.
Hemoglobin ; 41(2): 77-82, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28617057

RESUMO

Sickle cell disease affects about 150,000 births annually in Nigeria. Early diagnosis is hampered by factors such as centralized and urban localization of laboratories, high cost of diagnostic equipment and inadequate skilled manpower to operate them. The need for a low-cost, portable, easy-to-use diagnostic test for sickle cell disease is critical, especially in resource-poor countries. In this study, we evaluated the performance characteristics of a novel point-of-care testing device (SickleSCAN™), and its acceptability and feasibility, as a possible screening tool for sickle cell disease. In the first phase, we assessed the performance characteristics of SickleSCAN™ by evaluating 57 subjects comprising both children and adults attending a primary health center, for Hb SS (ßS/ßS; HBB: c.20A>T), Hb SC (ßS/ßC; HBB: c.19G>A) and Hb AS (ßA/ßS) using SickleSCAN™, cellulose acetate electrophoresis (CAE) and high performance liquid chromatography (HPLC). Performance characteristics such as diagnostic sensitivity and specificity were compared to HPLC as a standard method. We subsequently undertook a second phase wherein the acceptability and feasibility of the device for sickle cell disease screening, was evaluated using semi-structured and structured questionnaires among 197 healthcare personnel and 221 subjects, respectively. Sickle cell disease was carried by 3.4% of the subjects. The diagnostic sensitivity, specificity and test efficiency of SickleSCAN™ for sickle cell disease (Hb SS and Hb SC), were 100.0, 98.2 and 98.2%, respectively. Findings from this study showed SickleSCAN™ to be a viable screening tool that can easily be applied in community-based screening for early diagnosis of sickle cell disease with little expertise and low cost.


Assuntos
Anemia Falciforme/diagnóstico , Hemoglobina Falciforme/análise , Sistemas Automatizados de Assistência Junto ao Leito , Adolescente , Adulto , Anemia Falciforme/sangue , Criança , Pré-Escolar , Eletroforese em Acetato de Celulose/instrumentação , Eletroforese em Acetato de Celulose/métodos , Feminino , Hemoglobina Falciforme/metabolismo , Humanos , Lactente , Recém-Nascido , Masculino
15.
BMJ Open ; 14(1): e077200, 2024 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-38286692

RESUMO

INTRODUCTION: Sickle cell disease (SCD) and sickle cell traits (SCT) are genetically inherited red blood cell disorders common among people of African descent. Nigeria has a high prevalence of SCD, with a prevalence of 2.28%-3% and SCT, 25%-30%. Poorly managed SCD and SCT can lead to sensorineural hearing loss and health-related quality of life (HRQoL) issues. This research aims to assess these possible complications of SCD and SCT in Nigeria. METHODS AND ANALYSIS: The study will use a comparative cross-sectional design at study power 80% to investigate the association between SCD/SCT, hearing impairment and HRQoL. Participants will be divided into two groups: a cohort and a control group. Hearing levels will be assessed through audiometric assessments and categorised by type and severity of hearing impairments using WHO classifications. HRQoL will also be assessed using WHO Disability Assessment Schedule 2.0. Statistical analyses will be performed using the SAS V.9.4, with parametric or non-parametric analysis depending on the distribution. Relationship between key variables will be determined via correlational tests, χ2, Fisher's exact test and multivariable logistic regression analyses. ETHICS AND DISSEMINATION: The proposal has been fully reviewed and registered by the University of Cape Town's Faculty of Health Sciences Human Research Ethics Committee (HREC REF 228/2022) and the University of Abuja Teaching Hospital Human Research Ethics Committee (HREC/PR/2020/08/007). Information dissemination will be through conferences, peer-review publication and personal communications. The Strengthening the Reporting of Observational Studies in Epidemiology statement will be followed in writing the manuscript.


Assuntos
Anemia Falciforme , Perda Auditiva , Traço Falciforme , Humanos , Traço Falciforme/complicações , Traço Falciforme/epidemiologia , Estudos Transversais , Nigéria/epidemiologia , Qualidade de Vida , Anemia Falciforme/complicações , Anemia Falciforme/epidemiologia , Perda Auditiva/etiologia , Perda Auditiva/complicações , Hospitais de Ensino
16.
Front Genet ; 14: 1052444, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36816043

RESUMO

Background: Sickle cell disease (SCD) continues to pose physical and psychosocial burdens to patients, caregivers and health workers. Stakeholder engagement in the processes of policy making and implementation is increasingly becoming the cornerstone of best practices in healthcare. Aim and Objectives: To engage stakeholders with a view to assessing the knowledge of SCD; ascertain the challenges associated with accessibility and affordability of healthcare services; improve the quality of care, and thereby effect behavioral change through increasing attendance and follow-up of patients in the clinics. Methodology: A Stakeholders' Engagement meeting organized by the Sickle Pan Africa Research Consortium Nigeria Network (SPARC-NEt) was attended by patients, caregivers and members of patient support groups, healthcare providers and management/policymakers. The engagement was through PowerPoint presentations, structured questionnaires and an interactive session. The structured questionnaire assessed the knowledge of stakeholders about SCD; the quality of healthcare services; challenges with access and affordability; and SCD-related government policies. Results: Three hundred and twelve stakeholders attended the engagement meeting. Of the 133 that participated in the study, medical workers were the most represented. The majority had good knowledge of what causes SCD (96.2%) and the best place to get help during SCD crisis (98.5%). However, knowledge of the specific preventive measures of SCD and its crisis was not optimal. In terms of the role of community engagement and education, only about one-quarter of the study participants, 34 (25.6%) knew about their positive role in reducing the prevalence of SCD and alleviating SCD crises. Challenges identified include inadequate healthcare personnel and facilities, delay in obtaining laboratory results, long waiting time in the clinic, poor communication, absence of holistic consultation, uncoordinated healthcare services, high cost of care, ignorance, non-prioritization of SCD by government, lack of multisectoral collaboration and partnership with NGOs and international organizations. Strategies proffered to improve healthcare services include, community/stakeholder engagement and health education, sickle cell daycare services, access to a willing and dedicated multidisciplinary workforce, collaboration with support groups and government policies and programs. Conclusion: There is need for regular stakeholder engagement to improve access to healthcare services for SCD patients in Nigeria.

17.
Curr Stem Cell Res Ther ; 17(4): 339-347, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35189805

RESUMO

Sickle cell disease (SCD) is one of the most common haemoglobinopathies worldwide, with up to 70 % of global SCD annual births occurring in sub-Saharan Africa. Reports have shown that 50 to 80 % of affected children in these countries die annually. Efforts geared towards understanding and controlling HbF production in SCD patients could lead to strategies for effective control of globin gene expression and therapeutic approaches that could be beneficial to individuals with haemoglobinopathies. Hemopoietic stem cells (HSCs) are characterized by a specific miRNA signature in every state of differentiation. The role of miRNAs has become evident both in the maintenance of the "stemness" and in the early induction of differentiation by modulation of the expression of the master pluripotency genes and during early organogenesis. miRNAs are extra regulatory mechanisms in hematopoietic stem cells (HSCs) via influencing transcription profiles together with transcript stability. miRNAs have been reported to be used to reprogram primary somatic cells toward pluripotency. Their involvement in cell editing holds the potential for therapy for many genetic diseases. This review provides a snapshot of miRNA involvement in cell fate decisions, haemoglobin induction pathway, and their journey as some emerge prime targets for therapy in beta haemoglobinopathies.


Assuntos
Anemia Falciforme , Hemoglobinopatias , MicroRNAs , Anemia Falciforme/tratamento farmacológico , Anemia Falciforme/genética , Criança , Hemoglobina Fetal/genética , Hemoglobina Fetal/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Hemoglobinopatias/genética , Hemoglobinopatias/terapia , Humanos , MicroRNAs/genética , MicroRNAs/uso terapêutico
18.
Front Genet ; 13: 1013858, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36386848

RESUMO

Background: HemoTypeSC is a rapid, point-of-care testing (POCT) device for sickle cell disease (SCD) that traditionally uses the capillary blood from heel stick collected at the point of testing, a procedure that makes mass screening cumbersome and less cost-effective. Using dried blood spots (DBS) on HemoTypeSC could mitigate this challenge. Therefore, this study aimed to determine the feasibility of eluting blood from DBS to read on HemoTypeSC. Methods: DBS and fresh samples from heel sticks were collected from 511 newborns at the immunization clinics of six Primary Health Centers in Abuja, Nigeria. The two samples from each newborn were analyzed using HemoType SC and then compared with the result of the isoelectric focusing (IEF) test. Results: Of the 511 newborns, 241 were males and 270 were females. Standard HemoTypeSC (using fresh samples collected from heel sticks) and HemoTypeSC using DBS identified 404 (79.0%) HbAA, 100 (19.6%) HbAS, 6 (1.2%) HbSS, and 1 (0.2%) HbAC phenotypes. The IEF tests identified 370 (72.4%) HbAA, 133 (26.0%) HbAS, 5 (1.0%) HbSS, and 3 (0.6%) HbAC phenotypes. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and overall accuracy of HemoTypeSC using DBS, compared to standard HemoTypeSC POCT was 100%. IEF method showed for AA, AS, AC phenotypes; sensitivity; 84.7%, 67%,100% respectively, specificity; 67.6%, 86%, 99% respectively, PPV; 91.2%, 53%, 50% respectively, NPV; 52.7%, 91%, 100% respectively. For SS phenotype, IEF showed 100% specificity, sensitivity, PPV and NPV. Conclusion: HemoTypeSC test using dried blood spot is as accurate as the standard point-of-care HemoTypeSC test. The use of DBS on HemoTypeSC could ensure better efficiency and cost-effectiveness in mass newborn screening for SCD.

19.
Front Genet ; 13: 805806, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35783259

RESUMO

Skills development, the building of human capacity, is key to any sustainable capacity building effort, however, such undertakings require adaptable and tailored strategies. The Sickle Pan-African Research Consortium (SPARCo) is building capacity in sickle cell disease (SCD) management and research in sub-Saharan Africa, including a multi-national SCD patient registry, this is underpinned by skills development activities in data, research, and SCD management. Method: The SPARCo Skills Working Group was set up with the mandate of coordinating skills development activities across the three SPARCo sites in Ghana, Nigeria and Tanzania. To tailor activities to the requirements of the consortium, a needs assessment was conducted at the start of the project which identified skills required for SCD management and research and catalogued existing external and internal training programmes. The needs assessment highlighted differences in skill levels between the sites and different organisational structures which required tailored skills development activities at individual, site and consortium levels. Strategy: Based on the needs and the resources available, different types of training activities were implemented: these included online, blended and face to face activities. In order to create a sustainable skills development programme, existing short, medium, long-term, on-job training activities were used wherever possible. World Sickle Cell Day (19th June) was leveraged for training and health education activities. Results: SPARCo has recorded 1,726 participants in skills development activities across the three sites. Skills have been enhanced in data management, SCD and research to underpin the core deliverables of SPARCo. Conclusion and Lessons Learned: The baseline needs assessments and continual review and adjustment were critical for development of an effective skill development strategy for the consortium. This adaptability was particularly valuable during the COVID-19 pandemic. The sustainability plan leveraged existing programmes and activities and has created a pool of people with required skills for health care and research in SCD. To be effective, skills development programmes need to take into account existing capacity, training opportunities and local conditions. The model was applied to SCD and is adaptable to other skills development in healthcare and research in low and middle- income countries.

20.
BMJ Open ; 12(11): e063369, 2022 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-36385021

RESUMO

OBJECTIVES: To estimate the fraction of anaemia attributable to malaria and sickle cell disease (SCD) among children aged 6-59 months in Nigeria. DESIGN: Cross-sectional analysis of data from Nigeria's 2018 Demographic and Health Survey (DHS). SETTING: Nigeria. PARTICIPANTS: 11 536 children aged 6-59 months from randomly selected households were eligible for participation, of whom 11 142 had complete and valid biomarker data required for this analysis. Maternal education data were available from 10 305 of these children. PRIMARY OUTCOME MEASURE: Haemoglobin concentration. RESULTS: We found that 70.6% (95% CI: 62.7% to 78.5%) of severe anaemia was attributable to malaria compared with 12.4% (95% CI: 11.1% to 13.7%) of mild-to-severe and 29.6% (95% CI: 29.6% to 31.8%) of moderate-to-severe anaemia and that SCD contributed 0.6% (95% CI: 0.4% to 0.9%), 1.3% (95% CI: 1.0% to 1.7%) and 10.6% (95% CI: 6.7% to 14.9%) mild-to-severe, moderate-to-severe and severe anaemia, respectively. Sickle trait was protective against anaemia and was associated with higher haemoglobin concentration compared with children with normal haemoglobin (HbAA) among malaria-positive but not malaria-negative children. CONCLUSIONS: This approach used offers a new tool to estimate the contribution of malaria to anaemia in many settings using widely available DHS data. The fraction of anaemia among young children in Nigeria attributable to malaria and SCD is higher at more severe levels of anaemia. Prevention of malaria and SCD and timely treatment of affected individuals would reduce cases of severe anaemia.


Assuntos
Anemia Falciforme , Malária , Pré-Escolar , Humanos , Anemia Falciforme/complicações , Anemia Falciforme/epidemiologia , Estudos Transversais , Demografia , Hemoglobinas , Malária/complicações , Malária/epidemiologia , Nigéria/epidemiologia , Lactente
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