Hydroxyurea Therapy for Neurological and Cognitive Protection in Pediatric Sickle Cell Anemia in Uganda (BRAIN SAFE II): Protocol for a single-arm open label trial.

Background: Children with sickle cell anemia (SCA) in Sub-Saharan Africa are at high risk of sickle cerebrovascular injury (SCVI). Hydroxyurea, a commonly used disease-modifying therapy, may prevent or decrease SCVI for reduced incident stroke, stroke risk and potentially cognitive dysfunction. We aim to test the impact of daily hydroxyurea therapy on these outcomes in Ugandan children with SCA. We hypothesize that hydroxyurea therapy over 36 months will prevent, stabilize or improve these complications of SCA. Methods: The BRAIN SAFE II study is an open-label, single-arm trial of daily hydroxyurea for 270 children with SCA (HbSS) in Uganda, ages 3-9 years. Following baseline assessments, participants began hydroxyurea therapy and clinically followed per local guidelines. Standard hydroxyurea dose is escalated to maximum tolerated dose (MTD). SCVI is assessed by cerebral arterial velocity using Doppler ultrasound, with cognitive function determined by formal neurocognitive testing (primary outcomes). Structural SCVI is assessed by magnetic resonance imaging (MRI) and angiography (MRA) in a sub-sample of 90 participants ages ≥5 years, along with biomarkers of anemia, inflammation and malnutrition (secondary outcomes). At trial midpoint (18 months) and completion (36 months), primary outcomes will be compared to participants' baseline to determine hydroxyurea impact and relationships to secondary outcomes. Conclusion: This open-label, single-arm trial will examine the impact of hydroxyurea on preventing or ameliorating SCA SCVI in children, assessed by reducing incident stroke, stroke risk and neurocognitive dysfunction. Trial results will provide important insight into the role of hydroxyurea therapy on critical manifestations of SCVI in children with SCA.

Neurocognitive Impairment in Ugandan Children with Sickle Cell Anemia Compared to Sibling Controls: A cross-sectional study.

Introduction: Neurocognitive function in Ugandan children aged 1-12 years with sickle cell anemia (SCA) were compared to their non-SCA siblings to identify risk factors for disease-associated impairment. Methods: This cross-sectional neurocognitive function study of children with SCA (N=242) and non-SCA siblings (N=127) used age- and linguistically-appropriate standardized tests of cognition, executive function and attention for children ages 1-4 and 5-12 years. Test scores were converted to locally derived age-normalized z-scores. The SCA group underwent standardized stroke examination for prior stroke and transcranial doppler ultrasound (TCD) to determine stroke risk by arterial flow velocity. Results: The SCA group was younger than siblings (mean ages 5.46±3.0 versus 7.11±3.51 years, respectively; p <.001), with lower hemoglobin concentration (7.32±1.02 vs. 12.06±1.42, p <.001). Overall cognitive SCA z-scores were lower: -0.73 ±0.98 vs. siblings -0.25 ±1.12 (p<.001), with comparable findings for executive function of -1.09±0.94 versus -0.84±1.26 (p=0.045), respectively. Attention z-scores for ages 5-12 for the SCA group and controls were similar: -0.37±1.4 vs. -0.11±0.17 (p=.09). Overall differences by SCA status were largely driven by the older age group, as z-scores in the younger sub-sample did not differ from controls. Analyses revealed the strongest predictors of poor neurocognitive outcomes among the SCA sample to be the disease, age and prior stroke (each p<.001). Impact from anemia and SCA were indistinguishable. Discussion: Neurocognitive testing in children with SCA compared to non-SCA siblings revealed poorer SCA-associated functioning in children older than age 4. Results indicate need for trials assessing impact from disease modification for children with SCA.

Neurofilament light chain: A potential biomarker for cerebrovascular disease in children with sickle cell anaemia.

Cerebrovascular injury frequently occurs in children with sickle cell anaemia (SCA). Limited access to magnetic resonance imaging and angiography (MRI-MRA) in sub-Saharan Africa impedes detection of clinically unapparent cerebrovascular injury. Blood-based brain biomarkers of cerebral infarcts have been identified in non-SCA adults. Using plasma samples from a well-characterized cross-sectional sample of Ugandan children with SCA, we explored relationships between biomarker levels and MRI-detected cerebral infarcts and transcranial Doppler (TCD) arterial velocity. Testing was performed using a 4-plex panel of brain injury biomarkers, including neurofilament light chain (NfL), a central nervous system neuron-specific protein. Mean biomarker levels from the SCA group (n = 81) were similar to those from non-SCA sibling controls (n = 54). Within the SCA group, NfL levels were significantly higher in those with MRI-detected infarcts compared to no infarcts, and higher with elevated TCD velocity versus normal velocity. Elevated NfL remained strongly associated with MRI-detected infarcts after adjusting for sex and age. All non-SCA controls and SCA participants lacking MRI-detected infarcts had low NfL levels. These data suggest potential utility of plasma-based NfL levels to identify children with SCA cerebrovascular injury. Replication and prospective studies are needed to confirm these novel findings and the clinical utility of NfL versus MRI imaging.

Health-related quality of life of patients with sickle cell disease aged 8-17 years at Kamuzu Central Hospital, Malawi.

BACKGROUND: Sickle cell disease (SCD) is characterized by both acute and chronic complications that affect the daily lives of patients and lower their quality of life. OBJECTIVE: To describe the health-related quality of life (HRQoL) and the associated factors in children aged 8-17 years with SCD attending the pediatric hematology clinic at Kamuzu Central Hospital (KCH) in Lilongwe, Malawi. METHODS: A mixed-methods cross-sectional study was conducted at KCH. Patient data were collected with the aid of a standardized case report form. HRQoL was assessed using PedsQL™ Sickle Cell Disease Module by the child's report. Associations between HRQoL scores and independent variables were evaluated by a linear regression model. In-depth interviews were then carried out and the qualitative data were analyzed using content thematic analysis. RESULTS: A hundred and sixty-three children with SCD were enrolled and 52.1% were females. Their median age was 11.2 ± 2.7 years. The mean global HRQoL score of the children was 62 ± 17.3. The highest scores were in the treatment domain (72.5 ± 15.1) while the lowest scores were in the emotions domain (55.2 ± 28.7). The mean pain score was 58.8 ± 16.3. The factors associated with low HRQoL scores were pain (ß-coefficient -6.97 CI (-3.07,-15.58); p value .034) and low hemoglobin levels (ß-coefficient 2.29 CI (.65-3.91); p value .006). CONCLUSION: The HRQoL of this population is low. Pain and low hemoglobin were significantly associated with low HRQoL scores. Adequate treatment to control pain and increase the steady-state hemoglobin may improve the HRQoL of children with SCD. Interventions to address low emotional scores are recommended.

Brain Magnetic Resonance Imaging and Angiography in Children with Sickle Cell Anaemia in Uganda in a Cross-Sectional Sample.

OBJECTIVE: Children with sickle cell anaemia (SCA) are highly susceptible to cerebrovascular injury. We performed brain magnetic resonance imaging and angiography (MRI-MRA) in Ugandan children with SCA to identify structural cerebrovascular abnormalities and examine their relationship to standardized clinical assessments. METHODS: A sub-sample (n=81) was selected from a cross-sectional study of children attending SCA clinic, including 52 (64.2%) with and 29 (35.8%) without clinically detected abnormalities. Clinical evaluation included assessment for prior stroke, cognitive testing and cerebral arterial transcranial doppler (TCD) flow velocity. MRI-MRA scans were interpreted by at least two neuroradiologists. RESULTS: Mean age was 6.5±2.7 years, with 39 (48.1%) female. Mean haemoglobin was 7.3±0.9 g/dl. Overall, 13 (16.0%) were malnourished. Infarcts and/or stenoses were detected in 55 (67.9%) participants, with stenoses primarily in the anterior circulation. Infarcts were seen in those with normal 17/29 (58.6%) or abnormal 34/52 (65.4%) clinical testing (p=0.181). Neither abnormal MRI nor MRA was associated with age, sex, haemoglobin, or malnutrition. Abnormal MRA was highly associated with infarcts (p<0.0001). Participants with abnormal imaging had two-fold higher proportion of stroke on exam and/or impaired cognition. Stroke on exam was strongly associated with an imaging abnormality after adjusting for age, sex, malnutrition, and haemoglobin (OR 11.8, 95%CI 1.87-74.2). CONCLUSION: Over half of these SCA children had cerebrovascular infarcts and/or arterial stenoses. Cerebrovascular disease was frequently undetectable by clinical assessments. While rarely available in under-resourced settings, MRI-MRA brain imaging is an important tool for defining SCA cerebrovascular disease and for assessing impact of clinical intervention trials.

Adverse events following immunization reporting and impact on immunization services in informal settlements in Nairobi, Kenya: a prospective mixed-methods study.

INTRODUCTION: adverse events following immunization (AEFIs) are thought to contribute to cases of vaccine hesitancy, yet little data exists describing the state of reporting and management of AEFIs. This study investigated the occurrence and influence of AEFIs on vaccine hesitancy in an informal settlement of Nairobi. METHODS: this was a prospective mixed-methods study involving 7 focus group discussions, 8 key informant interviews and 457 face-to-face interviews with caregivers. Caregivers were recruited at/or before the 6 week clinic visit and assessed for occurrence of AEFIs in their children at the subsequent 10- and 14-week visits and a follow-up two weeks following the 14 weeks visit via phone calls. RESULTS: in this study, 12.3% (56/457) of the infants experienced an AEFI. Of these, 19 did not report for the next scheduled vaccine. Fever was the most common AEFI, for which most caregivers (66.7%) used Paracetamol as antipyretic, while 20.8% sought help from a nearby health facility. Three of the 56 AEFIs (convulsions) that occurred in study participants could be classified as severe reactions. Diphtheria, pertussis and tetanus (DPT 3) completion rate was 75.3%. Most (96.4%) caregivers considered immunization an important strategy for child survival. Vaccine hesitancy occurred among 3.6% of participants, 30% of whom attributed their hesitancy to occurrence of AEFIs. The review of health records revealed that no AEFI had been reported from any of the study facilities. CONCLUSION: cases of adverse events following immunization are not reported in Mathare Valley and they do have implications for vaccine hesitancy by some caregivers.

Orbital compression syndrome in a Ugandan child with sickle cell disease: A case report.

Orbital compression syndrome is a rare acute complication of sickle cell disease that may impair vision. Assessment by a multidisciplinary team incorporates detailed history and physical examination, fundoscopy, and appropriate imaging to exclude infections or neoplasms. Supportive treatment is adequate unless there is evidence of life-threatening space-occupying lesion warranting surgery.

Transfusion management of severe anaemia in African children: a consensus algorithm.

The phase III Transfusion and Treatment of severe anaemia in African Children Trial (TRACT) found that conservative management of uncomplicated severe anaemia [haemoglobin (Hb) 40-60 g/l] was safe, and that transfusion volume (20 vs. 30 ml/kg whole blood equivalent) for children with severe anaemia (Hb <60 g/l) had strong but opposing effects on mortality, depending on fever status (>37·5°C). In 2020 a stakeholder meeting of paediatric and blood transfusion groups from Africa reviewed the results and additional analyses. Among all 3196 children receiving an initial transfusion there was no evidence that nutritional status, presence of shock, malaria parasite burden or sickle cell disease status influenced outcomes or modified the interaction with fever status on volume required. Fever status at the time of ordering blood was a reliable determinant of volume required for optimal outcome. Elevated heart and respiratory rates normalised irrespective of transfusion volume and without diuretics. By consensus, a transfusion management algorithm was developed, incorporating three additional measurements of Hb post-admission, alongside clinical monitoring. The proposed algorithm should help clinicians safely implement findings from TRACT. Further research should assess its implementation in routine clinical practice.

The Sickle Cell Disease Ontology: Enabling Collaborative Research and Co-Designing of New Planetary Health Applications.

Sickle cell disease (SCD) is one of the most common blood disorders impacting planetary health. Over 300,000 newborns are diagnosed with SCD each year globally, with an increasing trend. The sickle cell disease ontology (SCDO) is the most comprehensive multidisciplinary SCD knowledge portal. The SCDO was collaboratively developed by the SCDO working group, which includes experts in SCD and data standards from across the globe. This expert review presents highlights and lessons learned from the fourth SCDO workshop that marked the beginning of applications toward planetary health impact, and with an eye to empower and cultivate multisite SCD collaborative research. The workshop was organized by the Sickle Africa Data Coordinating Center (SADaCC) and attended by 44 participants from 14 countries, with 2 participants connecting remotely. Notably, from the standpoint of democratizing and innovating scientific meeting design, an SCD patient advocate also presented at the workshop, giving a broader real-life perspective on patients' aspirations, needs, and challenges. A major component of the workshop was new approaches to harness SCDO to harmonize data elements used by different studies. This was facilitated by a web-based platform onto which participants uploaded data elements from previous or ongoing SCD-relevant research studies before the workshop, making multisite collaborative research studies based on existing SCD data possible, including multisite cohort, SCD global clinical trials, and SCD community engagement approaches. Trainees presented proposals for systematic literature reviews in key SCD research areas. This expert review emphasizes potential and prospects of SCDO-enabled data standards and harmonization to facilitate large-scale global SCD collaborative initiatives. As the fields of public and global health continue to broaden toward planetary health, the SCDO is well poised to play a prominent role to decipher SCD pathophysiology further, and co-design diagnostics and therapeutics innovation in the field.

Burden of neurological and neurocognitive impairment in pediatric sickle cell anemia in Uganda (BRAIN SAFE): a cross-sectional study.

BACKGROUND: Children with sickle cell anemia (SCA) are highly susceptible to stroke and other manifestations of pediatric cerebral vasculopathy. Detailed evaluations in sub-Saharan Africa are limited. METHODS: We aimed to establish the frequency and types of pediatric brain injury in a cross-sectional study at a large SCA clinic in Kampala, Uganda in a randomly selected sample of 265 patients with HbSS ages 1-12 years. Brain injury was defined as one or more abnormality on standardized testing: neurocognitive impairment using an age-appropriate test battery, prior stroke by examination or transcranial Doppler (TCD) velocities associated with stroke risk in children with SCA (cerebral arterial time averaged mean maximum velocity ≥ 170 cm/second). RESULTS: Mean age was 5.5 ± 2.9 years; 52.3% were male. Mean hemoglobin was 7.3 ± 1.01 g/dl; 76.4% had hemoglobin < 8.0 g/dl. Using established international standards, 14.7% were malnourished, and was more common in children ages 5-12. Overall, 57 (21.5%) subjects had one to three abnormal primary testing. Neurocognitive dysfunction was found in 27, while prior stroke was detected in 15 (5.7%). The most frequent abnormality was elevated TCD velocity 43 (18.1%), of which five (2.1%) were in the highest velocity range of abnormal. Only impaired neurocognitive dysfunction increased with age (OR 1.44, 95%CI 1.23-1.68), p < 0.001). In univariate models, malnutrition defined as wasting (weight-for-height ≤ -2SD), but not sex or hemoglobin, was modestly related to elevated TCD (OR 1.37, 95%CI 1.01-1.86, p = 0.04). In adjusted models, neurocognitive dysfunction was strongly related to prior stroke (OR 6.88, 95%CI 1.95-24.3, p = .003) and to abnormal TCD (OR 4.37, 95%CI 1.30, p = 0.02). In a subset of 81 subjects who were enriched for other abnormal results, magnetic resonance imaging and angiography (MRI/MRA) detected infarcts and/or arterial stenosis in 52%. Thirteen subjects (25%) with abnormal imaging had no other abnormalities detected. CONCLUSIONS: The high frequency of neurocognitive impairment or other abnormal results describes a large burden of pediatric SCA brain disease in Uganda. Evaluation by any single modality would have underestimated the impact of SCA. Testing the impact of hydroxyurea or other available disease-modifying interventions for reducing or preventing SCA brain effects is warranted.

Health-related quality of life of adolescents with sickle cell disease in sub-Saharan Africa: a cross-sectional study.

BACKGROUND: Sickle cell disease (SCD) is a chronic hematologic disease associated with increased morbidity and mortality. Hemoglobinopathies are the most prevalent genetic disease globally, and SCD is estimated to affect 0.7% of Ugandan. The disease may adversely impact on the quality of life of sickle cell patients. This study aimed to evaluate the health related quality of life (HRoL) of adolescents with SCD. METHODS: This was a mixed-methods study of adolescents with sickle cell disease and their caretakers living in Kampala city, Uganda. All children aged 8-17 years with homozygous sickle cell disease attending the sickle cell clinic at Mulago Hospital during the study period were included in this study. Participants completed the PedsQL™ generic core scales parent-proxy and child self-report questionnaire during a routine clinic visit. HRQoL was the primary outcome measured. Socio-demographics and disease related data were obtained through personal interview with caretakers and reviewing patients' medical records. Mean scores were used for HRQoL and linear regression for associated factors. RESULTS: Of the 140 adolescents with SCD included in the study, 40% were male. A total of 95 adolescents (68%) were between the age of 8-12 years with a mean age of 14.25 years. The physical function was assessed slightly higher by adolescents with a mean score of57.5 ± 20.3 compare to caretakers with 52.8 ± 22.1(p < 0.001). As assessed by caretakers, physical HRQoL scores were negatively associated with pain about-10.02 CI [- 19.22, - 0.81](p = 0.033), whereas it was positively associated with Pneumococcal vaccine with the score of 28.43 CI [16.78,40.09](p < 0.001) as assessed by adolescents and 31.37CI [22.22,40.51](p < 0.001) by caretakers. Pneumococcal vaccination impacted positively the psychosocial functioning with a score of 8.67CI [1.51,15.84] (p = 0.018) as assessed by children and 15.94 CI [5.50,26.38](p = 0.003) as assessed by the caretakers. CONCLUSIONS: This study highlighted that pain was negatively associated with both physical and psychosocial functioning; whereas getting Pneumococcal vaccine was positively associated with both physical and psychosocial functioning as reported by children and caretakers.

Barriers to effective uptake and provision of immunization in a rural district in Uganda.

INTRODUCTION: Hoima, one of the largest districts in mid- western Uganda, has persistently performed poorly with low immunization coverage, high immunization drop outs rates and repeated outbreaks of vaccine preventable diseases especially measles. The objectives of this study were to evaluate the state of immunization services and to identify the gaps in immunization health systems that contribute to low uptake and completion of immunization schedules in Hoima District. METHODS: This was a cross sectional mixed methods study, utilizing both qualitative and quantitative approaches. A situation analysis of the immunization services was carried out using in-depth interviews with vaccinators, focus group discussions and key informant interviews with ethno-videography. Secondary data was sourced from records at headquarters and vaccination centres within Hoima District. The quantitative component utilized cluster random sampling with sample size estimated using the World Health Organization's 30 cluster sampling technique. RESULTS: A total of 311 caretaker/child pairs were included in the study. Immunization completion among children of age at least 12 months was 95% for BCG, 96% for OPV0, 93% for DPT1, 84.5% for DPT2, 81% for DPT3 and 65.5% for measles vaccines. Access to immunization centres is difficult due to poor road terrain, which affects effectiveness of outreach program, support supervision, mentorship and timely delivery of immunization program support supplies especially refrigerator gas and vaccines. Some facilities are under-equipped to effectively support the program. Adverse Events Following Immunization (AEFI) identification, reporting and management is poorly understood. CONCLUSION: Immunization services in Hoima District require urgent improvement in the following areas: vaccine supply, expanding service delivery points, more health workers, transport and tailored mechanisms to ensure adequate communication between health workers and caretakers.

Paediatric immunisation and chemoprophylaxis in a Ugandan sickle cell disease clinic.

AIM: We aimed to assess the receipt of recommended care for young children with sickle cell disease (SCD) in a central SCD clinic in Kampala Uganda, focusing on standard vaccination and antibacterial and antimalarial prophylaxis. METHODS: A cross-sectional assessment of immunisation status and timeliness and prescribed antibacterial and antimalarial prophylaxis was performed in a sample with SCD aged ≤71 months in Mulago Hospital SCD Clinic. Government-issued immunisation cards and clinic-issued visit records for prescribed prophylaxis were reviewed. RESULTS: Vaccinations were documented by immunisation cards in 104 patients, mean age 31.7 months (range 3-70 months). Only 48 (46.2%) received all doses of each of the four recommended vaccine types, including pneumococcal 10-valent conjugate vaccine (pneumococcal conjugate vaccine (PCV)-10), which became available in 2014. Vaccination completion was associated with younger age and, for polio, maternal employment. PCV-10 series was completed in 54.8% of the sample and in 18.2% of those aged 48-71 months. Of children completing all vaccination types, an average 68.8% were immunised on time, defined as <60 days beyond the recommended age. Only 17 (13.5%) children were both fully and timely vaccinated. In an overlapping sample of 147 children, with a mean age of 38.4 months (4-70 months), 81.6% had ≥1 documented prescription for penicillin and/or antimalarial prophylaxis. CONCLUSIONS: Standardised vaccination and antibacterial and antimalarial protective measures for young children at this central SCD clinic were incomplete, especially PCV-10 for age ≥24 months, and often late. Child age, but not general maternal demographics, were associated with vaccination and chemoprophylaxis. Clinic-based oversight may improve timely uptake of these preventative measures.

Low dose ketamine versus morphine for acute severe vaso occlusive pain in children: a randomized controlled trial.

BACKGROUND AND AIMS: Acute pain episodes associated with sickle cell disease (SCD) are very difficult to manage effectively. Opioid tolerance and side effects have been major roadblocks in our ability to provide these patients with adequate pain relief. Ketamine is cheap, widely safe, readily available drug, with analgesic effects at sub-anesthetic doses and has been used in wide range of surgeries, pediatric burns dressing change and cancer related pain however, literature concerning its use in sickle cell crises is still limited in our setting. This study aimed to establish if 1 mg/kg of intravenous ketamine is non inferior to intravenous morphine 0.1 mg/kg in severe SCD-associated pain. METHODS: We performed an institutional review board-approved randomized, prospective, double-blinded, active-control, non-inferiority trial at the national referral sickle cell center. Children between 7 and 18 years of age with severe painful sickle cell crisis, defined by numerical rating scale score of greater or equal to 7 were enrolled. Patients were consented and randomized to receive, either IV ketamine (LDK) 1 mg/kg or IV morphine (MOR) 0.1 mg/kg as an infusion over 10 min. The primary endpoint is maximal change in Numerical Rating Scale (NRS) pain score. Secondary outcomes were, incidence of adverse effects, optimal time to and duration of action of ketamine and incidence of treatment failures by treatment group. A clinically meaningful difference in validated pain scores was defined as 1.3 units. Assuming both treatments are on average equal, a sample size of 240 patients (120 per group) provided 95% power to demonstrate that IV LDK is non-inferior to IV morphine with a 0.05 level of significance and a 10% non-inferiority margin. All analyses were based on a modified intention to treat. This trial was registered with clinicaltrials.gov NCT02434939. RESULTS: Two hundred and forty patients were enrolled (LDK120, MOR120). Demographic variables and baseline NRS scores (8.9 vs. 9.2) were similar. LDK was comparable to MOR in the maximum change in NRS scores, 66.4% vs. 61.3% (MD 5.5; 95% CI -2.2 to -13.2). Time to achieve maximum reduction in NRS pain scores was at 19.8 min for LDK and 34.1 min for MOR. The average duration of action for LDK was 60 min. MOR had more patients still at maximum effect at 120 min (45.8% vs. 37.5%; RR 1.2; 95% CI 0.9-1.7). LDK patients were 11.3 times more likely to develop side effects, though were transient, anticipated and non-life threatening (37.5% vs. 3.3%). MOR had significantly more treatment failures 40% vs. 28.3% (RR 0.7; 95% CI 0.5-1.03, p=0.07) Vital signs and sedation scores were similar in both groups. CONCLUSIONS: Intravenous LDK at 1 mg/kg provides comparable analgesic effectiveness as IV MOR in the acute treatment of severe painful sickle cell crisis in children in the day care sickle cell center. However, it is associated with a high incidence of several transient, non-life threatening mild side effects. IMPLICATIONS: Intravenous ketamine at 1 mg/kg can be a reliable alternative to morphine in the management of severe painful sickle cell crisis especially in a resource limited area where morphine is not readily available.

Stroke Prevalence in Children With Sickle Cell Disease in Sub-Saharan Africa: A Systematic Review and Meta-Analysis.

Objectives. The prevalence of stroke among children with sickle cell disease (SCD) in sub-Saharan Africa was systematically reviewed. Methods. Comprehensive searches of PubMed, Embase, and Web of Science were performed for articles published between 1980 and 2016 (English or French) reporting stroke prevalence. Using preselected inclusion criteria, titles and abstracts were screened and full-text articles were reviewed. Results. Ten full-text articles met selection criteria. Cross-sectional clinic-based data reported 2.9% to 16.9% stroke prevalence among children with SCD. Using available sickle gene frequencies by country, estimated pediatric mortality, and fixed- and random-effects model, the number of affected individuals is projected as 29 800 (95% confidence interval = 25 571-34 027) and 59 732 (37 004-82 460), respectively. Conclusion. Systematic review enabled the estimation of the number of children with SCD stroke in sub-Saharan Africa. High disease mortality, inaccurate diagnosis, and regional variability of risk hamper more precise estimates. Adopting standardized stroke assessments may provide more accurate determination of numbers affected to inform preventive interventions.

Prevalence of stroke in children admitted with sickle cell anaemia to Mulago Hospital.

BACKGROUND: Stroke is a major complication of sickle cell anaemia (SCA). It occurs commonly in childhood with about 10 % of children with sickle cell anaemia getting affected by this complication. In Uganda, there is paucity of data on the prevalence of stroke in children admitted in a tertiary institution. We determined the prevalence of stroke amongst children with SCA admitted to Mulago National Referral Hospital in Uganda and described the ir co-morbidities. METHODS: We conducted a retrospective record review of children with SCA admitted from August 2012 to August 2014 to the Paediatric Haematology Ward of Mulago Hospital in Kampala, Uganda. The target population was SCA children age 6 months-17 years of age. A descriptive analysis was used to summarize the demographic characteristics and clinical diagnosis. RESULTS: There were 2,176 children with SCA admitted who were included in this study. There were 147 children with stroke. Their mean age 6.1, (SD 3), with a male to female ratio was 1:1 (71 males and 76 females). The M: F ratio of non-stroke children was 1.1:1 (1084 males and 945 females) with a mean age of 5.2, (SD 3). The prevalence of stroke was 6.8 % (147 of 2176). Amongst the children with stroke, 72.1 % (106 of 147) had co-morbidities which included severe anaemia 21.7 % (23 of 106), bacteraemia and vaso-occlusive crisis 17 % (18 of 106), pneumonia 8.4 % (9 of 106) and malaria 6.6 % (7 of 106). CONCLUSION: The prevalence of stroke in hospitalized Ugandan children with SCA was 6.8 %. Children with stroke were often admitted with other medical conditions such as severe anaemia, bacteraemia and vaso-occlusion.

Newborn screening and prophylactic interventions for sickle cell disease in 47 countries in sub-Saharan Africa: a cost-effectiveness analysis.

BACKGROUND: Sickle cell disease (SCD) constitutes a major public health problem in sub-Saharan Africa (SSA). Newborn screening and early subsequent clinical intervention can reduce early mortality and increase life expectancy, but have not been widely implemented in SSA. This analysis assesses the cost-effectiveness of a newborn screening and prophylactic intervention (NSPI) package for SCD in 47 SSA countries. METHODS: A lifetime Markov model with annual cycles was built with infants either being screened using isoelectric focusing (IEF) or not screened. Confirmed positive cases received interventions including insecticide-treated mosquito bed nets, folic acid supplementation, prophylactic antimalarial and penicillin therapy, and vaccinations against bacterial infections. Estimates for the local incidence of SCD, the life expectancy of untreated children, the SCD disability weight, and the cost of screening laboratory tests were based on published sources. Among treated infants, the annual probability of mortality until 30 years of age was derived from a pediatric hospital-based cohort. The outcome of interest included a country-specific cost per Disability Adjusted Life Year (DALY) averted. RESULTS: Of 47 modeled countries in SSA, NSPI is almost certainly highly cost-effective in 24 countries (average cost per DALY averted: US$184); in 10 countries, it is cost-effective in the base case (average cost per DALY averted: US$285), but the results are subject to uncertainty; in the remaining 13, it is most likely not cost-effective. We observe a strong inverse relationship between the incidence rate of SCD and the cost per DALY averted. Newborn screening is estimated to be cost-effective as long as the incidence rate exceeds 0.2-0.3 %, although in some countries NSPI is cost-effective at incidence rates below this range. In total, NSPI could avert over 2.4 million disability adjusted life years (DALYs) annually across SSA. CONCLUSIONS: Using IEF to screen all newborns for SCD plus administration of prophylactic interventions to affected children is cost-effective in the majority of countries in SSA.

Proceedings of a Sickle Cell Disease Ontology workshop - Towards the first comprehensive ontology for Sickle Cell Disease.

Sickle cell disease (SCD) is a debilitating single gene disorder caused by a single point mutation that results in physical deformation (i.e. sickling) of erythrocytes at reduced oxygen tensions. Up to 75% of SCD in newborns world-wide occurs in sub-Saharan Africa, where neonatal and childhood mortality from sickle cell related complications is high. While SCD research across the globe is tackling the disease on multiple fronts, advances have yet to significantly impact on the health and quality of life of SCD patients, due to lack of coordination of these disparate efforts. Ensuring data across studies is directly comparable through standardization is a necessary step towards realizing this goal. Such a standardization requires the development and implementation of a disease-specific ontology for SCD that is applicable globally. Ontology development is best achieved by bringing together experts in the domain to contribute their knowledge. The SCD community and H3ABioNet members joined forces at a recent SCD Ontology workshop to develop an ontology covering aspects of SCD under the classes: phenotype, diagnostics, therapeutics, quality of life, disease modifiers and disease stage. The aim of the workshop was for participants to contribute their expertise to development of the structure and contents of the SCD ontology. Here we describe the proceedings of the Sickle Cell Disease Ontology Workshop held in Cape Town South Africa in February 2016 and its outcomes. The objective of the workshop was to bring together experts in SCD from around the world to contribute their expertise to the development of various aspects of the SCD ontology.