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Brain injury is a common complication of sickle cell anaemia (SCA). White matter (WM) and cortical and subcortical grey matter (GM), structures may have reduced volume in patients with SCA. This study focuses on whether silent cerebral infarction (SCI), vasculopathy or anaemia affects WM and regional GM volumes in children living in Africa. Children with SCA (n = 144; aged 5-20 years; 74 male) and sibling controls (n = 53; aged 5-17 years; 29 male) underwent magnetic resonance imaging. Effects of SCI (n = 37), vasculopathy (n = 15), and haemoglobin were assessed. Compared with controls, after adjusting for age, sex and intracranial volume, patients with SCA had smaller volumes for WM and cortical, subcortical and total GM, as well as bilateral cerebellar cortex, globus pallidus, amygdala and right thalamus. Left globus pallidus volume was further reduced in patients with vasculopathy. Putamen and hippocampus volumes were larger in patients with SCA without SCI or vasculopathy than in controls. Significant positive effects of haemoglobin on regional GM volumes were confined to the controls. Patients with SCA generally have reduced GM volumes compared with controls, although some subcortical regions may be spared. SCI and vasculopathy may affect the trajectory of change in subcortical GM and WM volume. Brain volume in non-SCA children may be vulnerable to contemporaneous anaemia., (© 2022 The Authors. British Journal of Haematology published by British Society for Haematology and John Wiley & Sons Ltd.)

The enrolment of children and adolescents in health research requires that attention to be paid to specific assent and consent requirements such as the age range for seeking assent; conditions for parental consent (and waivers); the age group required to provide written assent; content of assent forms; if separate assent and parental consent forms should be used, consent from emancipated young adults; reconsent at the age of adulthood when a waiver of assent requirements may be appropriate and the conditions for waiving assent requirements. There is however very little available information for researchers and ethics committees on how to navigate these different issues. To provide guidance to research initiatives, the SickleInAfrica consortium conducted a thematic analysis of a sample of research ethics guidelines and procedures in African countries, to identify guidance for assent requirements in health research. The thematic analysis revealed that 12 of 24 African countries specified the age group for which assent is required. The minimum age for written assent varied across the countries. Five countries, Algeria, Botswana, Cameroon, Nigeria and The Democratic Republic of Congo require consent from both parents/family council in certain circumstances. Botswana, Nigeria, South Africa and Uganda have specific assent/consent requirements for research with emancipated minors. South Africa and Algeria requires re-consent at onset of adulthood. Five countries (Botswana, Cameroon, Nigeria, South Africa and Tanzania) specified conditions for waiving assent requirements. The CIOMS and the ICH-GCP guidelines had the most comprehensive information on assent requirements compared to other international guidelines. An interactive map with assent requirements for different African countries is provided. The results show a major gap in national regulations for the inclusion of minors in health research. The SickleInAfrica experience in setting up a multi-country SCD registry in Africa highlights the need for developing and harmonising national and international guidelines on assent and consent requirements for research involving minors. Harmonisation of assent requirements will help facilitate collaborative research across countries., (© 2022. The Author(s).)

Hydroxyurea (HU) alone has the potential to prevent one out of every three deaths due to sickle cell disease (SCD) and almost all forms of disabilities caused by SCD. However, in Tanzania, only one out of every six registered SCD patients in the SPARCO-Tanzania Sickle Cell Cohort use HU. We conducted studies to understand factors influencing utilization of HU in Tanzania and discovered that among the reason for low utilization of HU include HU is classified as anticancer medication, only hematologists are supposed to prescribe HU, limited HU prescription to only National and Specialized hospitals, a special permit is required to access HU using National Health Insurance Fund (NHIF) scheme and limited importation and absence of local manufacturing of HU limit availability of this important drug in Tanzania. Therefore, with this brief, the government should allow prescription of HU to the district hospitals level, should allow all clinicians with a minimum of a Bachelor of Medicine to prescribe HU, and accessibility of HU through NHIF should be friendly., Competing Interests: No competing interests were disclosed., (Copyright: © 2022 Kilonzi M et al.)

Background: Developmental difficulties in many cognitive domains are common in children with sickle cell anaemia (SCA). Children with stroke are most affected but delayed or atypical cognitive function has been reported in children with SCA and silent infarcts (SCI), vasculopathy, and normal brain MRI. However, very few studies of cognition have been conducted in Africa, a continent with 75% of the SCA burden. We therefore investigated cognitive profiles in Tanzanian children with SCA and examined the impact of age, SCI, vasculopathy, and haemoglobin concentration (Hb)., Methods: Children aged 6-16 years with and without SCA were eligible for this cross-sectional study. Cognitive assessment was performed using Raven's Matrices, assessing fluid, non-verbal intelligence and subtests from the Wechsler Intelligence Scales for Children (WISC-IV), assessing processing speed (PS), perceptual reasoning (PR), and working memory (WM) as these tests are less culture-bound. Magnetic resonance imaging (MRI) and angiography (MRA) were also completed to assess the presence of SCI and vasculopathy. Hb was collected in both SCA children and their non-SCA siblings., Results: Seventy-three children with SCA and 71 healthy siblings (Mean ages 11.9, SD = 2.8 and 11.1, SD = 2.9 years respectively) were recruited. Compared with healthy siblings, children with SCA had lower PS (Mean diff 7.35 points; p = .002). Older children had higher performance scores on all tests in relation to their ages. Lowest cognitive scores were observed on the PS subtest, where patients with SCI (SCI+) had lowest mean values as compared to children with no SCI (SCI-) and healthy siblings (i.e., SCI+ < SCI- < healthy siblings, p = .028). On post-hoc analysis the difference was between SCI+ and healthy siblings SCI+ < non-SCA siblings (p = .015); there was no difference between SCI+ and SCI- patient groups. PS was significantly lower in SCA patients with no vasculopathy as compared to healthy siblings. The mean difference from healthy siblings was -8.352 and -0.752 points for VASC- and VASC + respectively (p = .004). There was a significant positive effect of Hb on PSI (p = .001) in both patients and controls and a trend level significant positive effect of Hb on PR (p = .050) and WM (p = .051)., Conclusion: In this Tanzanian study, cognitive performance was reduced in children with SCA with or without SCI on MRI or vasculopathy. Cognitive performance improved with increasing age. Lower Hb was associated with lower cognitive performance in both patients with SCA and their non-SCA siblings. SCI and vasculopathy do not appear to have an impact on cognitive function., (Copyright © 2022. Published by Elsevier Ltd.)

Background: Sickle cell disease (SCD) is a global public health priority due to its high morbidity and mortality. In Tanzania, SCD accounts for 7% of under-five mortality. Cost-effective interventions such as early diagnosis and linkage to care have been shown to prevent 70% of deaths but require knowledge among healthcare workers and availability of resources at health facilities. In Tanzania, data on these critical determinants are currently lacking. Objective: To assess healthcare workers' knowledge and resource availability for care of SCD at health facilities in Dar es Salaam, Tanzania. Methodology: A facility-based cross-sectional study was conducted between December 2020 and February 2021 among 490 nurses and clinicians at Regional Referral Hospitals (Temeke, Amana, and Mwananyamala) and Muhimbili National Hospital in Dar es Salaam, Tanzania. Data were collected using a pre-tested structured questionnaire consisting of 13 knowledge questions (scored good knowledge if correct response in >7) and an inventory check list to record available resources. Pearson's χ 2 was used to determine the association between level of knowledge and demographic factors. Multivariate logistic regression was used to ascertain the strength of associations. A two-tailed p -value <0.05 was considered to be statistically significant. Results: Of the 490 participants (median age 28 years [IQR = 26-35]), only 25.1% had good knowledge on SCD. The odds of good knowledge was 82% lower in nurses than clinicians (AOR = 0.177; 95% CI: 0.090, 0.349; p < 0.001); 95% lower in diploma than Master's degree holders (AOR = 0.049; 95% CI: 0.008, 0.300; p = 0.001) and 4.6 times higher in those with 5-9 years than ≥10 years of experience (AOR = 4.564; 95% CI: 1.341, 15.525; p = 0.015). The regional-level hospitals lacked diagnostic tests and hydroxyurea therapy. Conclusion: There was general lack of knowledge on SCD among healthcare workers and limited availability of critical resources for the diagnosis and care of SCD, especially at regional-level hospitals. Efforts are needed for their improvement to enhance care to patients, thus reducing the morbidity and mortality due to SCD in Tanzania., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Jonathan, Tutuba, Lloyd, Ndunguru, Makani, Ruggajo, Minja and Balandya.)

Background: Cerebral infarcts and vasculopathy in neurologically asymptomatic children with sickle cell anemia (SCA) have received little attention in African settings. This study aimed to establish the prevalence of silent cerebral infarcts (SCI) and vasculopathy and determine associations with exposure to chronic hemolysis, anemia, and hypoxia., Methods: We prospectively studied 224 children with SCA with transcranial Doppler (TCD), and magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA). Regressions were undertaken with contemporaneous hemoglobin, reticulocyte count, mean prior hemoglobin, oxygen content, reticulocyte count, and indirect bilirubin., Results: Prevalence of SCI was 27% (61 of 224); cerebral blood flow velocity was abnormal (>200 cm/s) in three and conditional (>170<200 cm/s) in one. Vasculopathy grades 2 (stenosis) and 3 (occlusion) occurred in 16 (7%) and two (1%), respectively; none had grade 4 (moyamoya). SCI was associated with vasculopathy on MRA (odds ratio 2.68; 95% confidence intervals [95% CI] 1.32 to 5.46; P = 0.007) and mean prior indirect bilirubin (odds ratio 1.02, 95% CI 1.00 to 1.03, P = 0.024; n = 83) but not age, sex, non-normal TCD, or contemporaneous hemoglobin. Vasculopathy was associated with mean prior values for hemoglobin (odds ratio 0.33, 95% CI 0.16 to 0.69, P = 0.003; n = 87), oxygen content (odds ratio 0.43, 95% CI 0.25 to 0.74, P = 0.003), reticulocytes (odds ratio 1.20, 95% CI 1.01-1.42, P = 0.041; n = 77), and indirect bilirubin (odds ratio 1.02, 95% CI 1.01 to 1.04, P = 0.009)., Conclusions: SCI and vasculopathy on MRA are common in neurologically asymptomatic children with SCA living in Africa, even when TCD is normal. Children with vasculopathy on MRA are at increased risk of SCI. Longitudinal exposure to anemia, hypoxia, and hemolysis appear to be risk factors for vasculopathy., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)