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The emergence of drug-resistant Plasmodium falciparum parasites in sub-Saharan Africa will substantially challenge malaria control. Here, we evaluated the frequency of common drug resistance markers among adolescents from Northern Uganda with asymptomatic infections. We used an established amplicon deep sequencing strategy to screen dried blood spot samples collected from 2016 to 2017 during a reported malaria epidemic within the districts of Kitgum and Pader in Northern Uganda. We screened single-nucleotide polymorphisms within: kelch13 (Pfk13), dihydropteroate synthase (Pfdhps), multidrug resistance-1 (Pfmdr1), dihydrofolate reductase (Pfdhfr), and apical membrane antigen (Pfama1) genes. Within the study population, the median age was 15 years (14.3-15.0, 95% CI), and 54.9% (78/142) were Plasmodium positive by 18S rRNA qPCR, which were subsequently targeted for sequencing analysis. We observed a high frequency of resistance markers particularly for sulfadoxine-pyrimethamine (SP), with no wild-type-only parasites observed for Pfdhfr (N51I, C59R, and S108N) and Pfdhps (A437G and K540E) mutations. Within Pfmdr1, mixed infections were common for NF/NY (98.5%). While for artemisinin resistance, in kelch13, there was a high frequency of C469Y (34%). Using the pattern for Pfama1, we found a high level of polygenomic infections with all individuals presenting with complexity of infection greater than 2 with a median of 6.9. The high frequency of the quintuple SP drug-resistant parasites and the C469Y artemisinin resistance-associated mutation in asymptomatic individuals suggests an earlier high prevalence than previously reported from symptomatic malaria surveillance studies (in 2016/2017). Our data demonstrate the urgency for routine genomic surveillance programs throughout Africa and the value of deep sequencing.
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BACKGROUND: Most neonatal deaths occur among low birth weight infants. However, in resource-limited settings, these infants are commonly discharged early which further exposes them to mortality. Previous studies on morbidity and mortality among low birth weight infants after early discharge mainly focused on very low birth weight infants, and none described post-discharge neonatal mortality. This study aimed to determine the proportion and predictors of mortality among low birth weight neonates discharged from the Special Care Baby Unit at Mulago National Referral Hospital in Uganda. METHODS: This was a prospective cohort study of 220 low birth weight neonates discharged from the Special Care Baby Unit at Mulago National Referral Hospital. These were followed up to 28 completed days of life, or death, whichever occurred first. Proportions were used to express mortality. To determine the predictors of mortality, Cox hazards regression was performed. RESULTS: Of the 220 enrolled participants, 216 (98.1%) completed the follow-up. The mean gestational age of study participants was 34 ±3 weeks. The median weight at discharge was 1,650g (IQR: 1,315g -1,922g) and 46.1% were small for gestational age. During follow-up, 14/216 (6.5%) of neonates died. Mortality was highest (7/34, 20.6%) among neonates with discharge weights less than 1,200g. The causes of death included presumed neonatal sepsis (10/14, 71.4%), suspected aspiration pneumonia (2/14, 14.3%), and suspected cot death (2/14, 14.3%). The median time to death after discharge was 11 days (range 3-16 days). The predictors of mortality were a discharge weight of less than 1,200g (adj HR: 23.47, p <0.001), a 5-minute Apgar score of less than 7 (adj HR: 4.25, p = 0.016), and a diagnosis of neonatal sepsis during admission (adj HR: 7.93, p = 0.009). CONCLUSION: Post-discharge mortality among low birth weight neonates at Mulago National Referral Hospital is high. A discharge weight of less than 1,200g may be considered unsafe among neonates. Caregiver education about neonatal danger signs, and measures to prevent sepsis, aspiration, and cot death should be emphasized before discharge and during follow-up visits.
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Mortalidad Infantil , Recién Nacido de Bajo Peso , Alta del Paciente , Humanos , Uganda/epidemiología , Recién Nacido , Femenino , Masculino , Estudios Prospectivos , Lactante , Factores de Riesgo , Edad GestacionalRESUMEN
This study utilized a qualitative design to explore dietitians' perceptions regarding Ketogenic Diet Therapy (KDT) for patients with drug-resistant epilepsy in Kenya. Dietitians from Kenya were selected and consented. Audio-recorded interviews were conducted, followed by thematic analysis of verbatim transcripts to identify recurring patterns. The study enrolled 18 dietitians, fourteen of whom correctly described their understanding of KDT for managing drug-resistant epilepsy. There was a lack of confidence in their capacity to initiate the KDT with all expressing the need for further training and facilitation. Only one dietitian reported having initiated and maintained KDT. There was an overall positive view regarding KDT and willingness to implement KDT for patients with drug-resistant epilepsy. Dietitians expressed concerns regarding the availability of national policies, inadequate staffing to support families who require KDT, and the cost of implementing this intervention. Dietitians expressed interest in virtual training to enhance their understanding of KDT. Dietitians in Kenya are mostly aware of KDT utilization for the management of drug-resistant epilepsy. However, they cited poor capability and various barriers to implementation. There is a need for policies to facilitate KDT as a treatment option for the benefit of patients with drug-resistant epilepsy.
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Background: Malaria remains a major global health priority, and monoclonal antibodies (mAbs) are emerging as potential new tools to support efforts to control the disease. Recent data suggest that Fc-dependent mechanisms of immunity are important mediators of protection against the blood stages of the infection, but few studies have investigated this in the context of mAbs. We aimed to isolate mAbs agnostic to cognate antigens that target whole merozoites and simultaneously induce potent neutrophil activity measured by the level of reactive oxygen species (ROS) production using an antibody-dependent respiratory burst (ADRB) assay. Methods: We used samples from semi-immune adults living in coastal Kenya to isolate mAbs that induce merozoite-specific ADRB activity. We then tested whether modifying the expressed IgG1 isotype to an IgG-IgA Fc region chimera would enhance the level of ADRB activity. Results: We isolated a panel of nine mAbs with specificity to whole merozoites. mAb J31 induced ADRB activity in a dose-dependent fashion. Compared to IgG1, our modified antibody IgG-IgA bi-isotype induced higher ADRB activity across all concentrations tested. Further, we observed a negative hook effect at high IgG1 mAb concentrations (i.e., >200 µg/mL), but this was reversed by Fc modification. We identified MSP3.5 as the potential cognate target of mAb J31. Conclusions: We demonstrate an approach to engineer mAbs with enhanced ADRB potency against blood-stage parasites.
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Anticuerpos Monoclonales , Anticuerpos Antiprotozoarios , Malaria Falciparum , Merozoítos , Neutrófilos , Plasmodium falciparum , Plasmodium falciparum/inmunología , Humanos , Anticuerpos Antiprotozoarios/inmunología , Neutrófilos/inmunología , Neutrófilos/metabolismo , Malaria Falciparum/inmunología , Malaria Falciparum/parasitología , Anticuerpos Monoclonales/inmunología , Merozoítos/inmunología , Estallido Respiratorio/inmunología , Inmunoglobulina G/inmunología , Adulto , Especies Reactivas de Oxígeno/metabolismo , Kenia , Isotipos de Inmunoglobulinas/inmunología , Activación Neutrófila/inmunología , Femenino , Antígenos de Protozoos/inmunologíaRESUMEN
Background: Children exposed to severe malaria may recover with gross neurologic deficits (GND). Several risk factors for GND after cerebral malaria (CM), the deadliest form of severe malaria, have been identified in children. However, there is inconsistency between previously reported and more recent findings. Although CM patients are the most likely group to develop GND, it is not clear if other forms of severe malaria (non-CM) may also contribute to the malaria related GND. The aim of this systematic review is to synthesize evidence on the prevalence and risk factors for GND in children following CM and map the changes in patterns over time. In addition, this review will synthesize evidence on the reported prevalence and risk factors of gross neurologic deficits following other forms of severe malaria. Methods: The systematic review will be conducted according to recommendations of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Protocols (PRISMA-P). Relevant research articles will be identified using relevant search terms from the following databases: MEDLINE, Embase, Web of Science and Global Index Medicus (GIM). The articles will be screened at title and abstract, then at full text for inclusion using a priori eligibility criteria. Data extraction will be done using a tool developed and optimized in Excel spreadsheet. Risk of bias assessment will be done using appropriate tools including ROBINS-E ('Risk Of Bias In Non-randomized Studies of Exposure') tool, while publication bias will be assessed using funnel plot. A random-effects meta-analysis and structured narrative synthesis of the outcomes will be performed and results presented. Discussion: Findings from this systematic review will inform policy makers on planning, design and implementation of interventions targeting the treatment and rehabilitation of GND following severe malaria in children. Systematic review registration: The protocol is registered in the International Prospective Register of Systematic Reviews (PROSPERO), registration number CRD42022297109.
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BACKGROUND: Nodding syndrome is a poorly understood neurological disorder that predominantly occurs in Africa. We hypothesised that nodding syndrome is a neuroinflammatory disorder, induced by antibodies to Onchocerca volvulus or its Wolbachia symbiont, cross-reacting with host neuronal proteins (HNPs), and that doxycycline can be used as treatment. METHODS: In this randomised, double-blind, placebo-controlled, phase 2 trial, we recruited participants from districts affected by nodding syndrome in northern Uganda. We included children and adolescents aged 8-18 years with nodding syndrome, as defined by WHO consensus criteria. Participants were randomly assigned (1:1) to receive either 100 mg doxycycline daily or placebo for 6 weeks via a computer-generated schedule stratified by skin microscopy results, and all parties were masked to group assignment. Diagnoses of O volvulus and antibodies to HNPs were made using luciferase immunoprecipitation system assays and immunohistochemistry. The primary outcome was change in the proportion with antibodies to HNPs, assessed at 24 months. All participants were included in safety analyses, and surviving participants (those with samples at 24 months) were included in primary analyses. Secondary outcomes were: change in concentrations of antibodies to HNPs at 24 months compared with baseline; proportion of participants testing positive for antibodies to O volvulus-specific proteins and concentrations of Ov16 or OVOC3261 antibodies at 24 months compared with baseline; change in seizure burden, proportion achieving seizure freedom, and the proportions with interictal epileptiform discharges on the diagnostic EEG; overall quality of life; disease severity at 24 months; and incidence of all-cause adverse events, serious adverse events, and seizure-related mortality by 24 months. This trial is registered with ClinicalTrials.gov, NCT02850913. FINDINGS: Between Sept 1, 2016, and Aug 31, 2018, 329 children and adolescents were screened, of whom 240 were included in the study. 140 (58%) participants were boys and 100 (42%) were girls. 120 (50%) participants were allocated to receive doxycycline and 120 (50%) to receive placebo. At recruitment, the median duration of symptoms was 9 years (IQR 6-10); 232 (97%) participants had O volvulus-specific antibodies and 157 (65%) had autoantibodies to HNPs. The most common plasma autoantibodies were to human protein deglycase DJ-1 (85 [35%] participants) and leiomodin-1 (77 [32%] participants) and, in cerebrospinal fluid (CSF), to human DJ-1 (27 [11%] participants) and leiomodin-1 (14 [6%] participants). On immunohistochemistry, 46 (19%) participants had CSF autoantibodies to HNPs, including leiomodin-1 (26 [11%]), γ-aminobutyric acid B receptors (two [<1%]), CASPR2 (one [<1%]), or unknown targets (28 [12%]). At 24 months, 161 (72%) of 225 participants had antibodies to HNPs compared with 157 (65%) of 240 at baseline. 6 weeks of doxycycline did not affect the concentration of autoantibodies to HNPs, seizure control, disease severity, or quality of life at the 24-month follow-up but substantially decreased Ov16 antibody concentrations; the median plasma signal-to-noise Ov16 ratio was 16·4 (95% CI 6·4-38·4), compared with 27·9 (8·2-65·8; p=0·033) for placebo. 14 (6%) participants died and, other than one traffic death, all deaths were seizure-related. Acute seizure-related hospitalisations (rate ratio [RR] 0·43 [95% CI 0·20-0·94], p=0·028) and deaths (RR 0·46 [0·24-0·89], p=0·028) were significantly lower in the doxycycline group. At 24 months, 96 (84%) of 114 participants who received doxycycline tested positive for antibodies to Ov16, compared with 97 (87%) of 111 on placebo (p=0·50), and 74 (65%) participants on doxycycline tested positive for antibodies to OVOC3261, compared with 57 (51%) on placebo (p=0·039). Doxycycline was safe; there was no difference in the incidence of grade 3-5 adverse events across the two groups. INTERPRETATION: Nodding syndrome is strongly associated with O volvulus and the pathogenesis is probably mediated through an O volvulus induced autoantibody response to multiple proteins. Although it did not reverse disease symptoms, doxycycline or another prophylactic antibiotic could be considered as adjunct therapy to antiseizure medication, as it might reduce fatal complications from acute seizures and status epilepticus induced by febrile infections. FUNDING: Medical Research Council (UK). TRANSLATION: For the Luo translation of the abstract see Supplementary Materials section.
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Doxiciclina , Síndrome del Cabeceo , Humanos , Niño , Adolescente , Femenino , Masculino , Doxiciclina/uso terapéutico , Síndrome del Cabeceo/tratamiento farmacológico , Método Doble Ciego , Uganda , Resultado del Tratamiento , Antibacterianos/uso terapéutico , Onchocerca volvulus/efectos de los fármacosRESUMEN
Introduction: The neurocognitive functions 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 study of the neurocognitive functions in 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. Test scores were converted to locally derived age-normalized z-scores. The SCA group underwent a standardized stroke examination for prior stroke and transcranial Doppler ultrasound to determine stroke risk by arterial flow velocity. Results: The SCA group was younger than their siblings (mean ages 5.46 ± 3.0 vs. 7.11 ± 3.51 years, respectively; p < 0.001), with a lower hemoglobin concentration (7.32 ± 1.02 vs. 12.06 ± 1.42, p < 0.001). The overall cognitive SCA z-scores were lower, -0.73 ± 0.98, vs. siblings, -0.25 ± 1.12 (p < 0.001), with comparable findings for executive function of -1.09 ± 0.94 vs. -0.84 ± 1.26 (p = 0.045), respectively. The attention z-scores for ages 5-12 for the SCA group and control group were similar: -0.37 ± 1.4 vs. -0.11 ± 0.17 (p = 0.09). The overall differences in SCA status were largely driven by the older age group, as the z-scores in the younger subsample 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 < 0.001). The impacts of 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. The results indicate the need for trials assessing the impact of disease modification on children with SCA.
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Objective: Academic achievement in school-age children is crucial for advancing learning goals. Children with sickle cell anaemia (SCA) in Sub-Saharan Africa may be at risk of disease-associated school difficulties. Limited data exist on the academic achievement of children with SCA in the region. This study aimed to assess academic achievement of children with SCA in Uganda compared to siblings without SCA. Design and setting: A cross-sectional study conducted at Mulago Hospital SCA Clinic in Uganda. Participants: School-going children (6-12 years) with SCA and age-matched sibling controls without SCA. Outcome measures: Academic achievement was tested using the Wide Range Achievement Test, Fourth Edition (WRAT4). Outcome measures were spelling, mathematical computation, word reading, and sentence comprehension by age-normalized Z-scores on the WRAT4 test. Results: Among 68 SCA and 69 control, the mean age (standard deviation) was 9.44 (2.04) and 9.42 (2.02) years and males were 55.9% and 46.4% respectively. Mean haemoglobin was 7.9 (SD 0.89)g/dL in the SCA group versus 12.8 (SD 0.89)g/dL in the controls, (p<0.001). Children with SCA scored lower in spelling, (mean difference [95% confidence interval] - 0.36 [-0.02 to -0.69], p=0.04) and mathematical computation, (mean difference [95% confidence interval] -0.51 [-0.17 to -0.85], p=0.003) than the controls. In the SCA group, lower scores in spelling correlated with age, while males performed better than females in mathematical computation. Conclusion: School-aged children with SCA are at risk of poor performance in spelling and mathematical computation. Our findings support the need for educational evaluation and possible support, especially in these two areas.
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BACKGROUND: Severe anaemia is associated with high in-hospital mortality among young children. In malaria-endemic areas, surviving children also have an increased risk of mortality or readmission after hospital discharge. We conducted a systematic review and individual patient data meta-analysis to determine the efficacy of monthly post-discharge malaria chemoprevention in children recovering from severe anaemia. METHODS: This analysis was conducted according to PRISMA-IPD guidelines. We searched multiple databases on Aug 28, 2023, without date or language restrictions, for randomised controlled trials comparing monthly post-discharge malaria chemoprevention with placebo or standard of care among children (aged <15 years) admitted with severe anaemia in malaria-endemic Africa. Trials using daily or weekly malaria prophylaxis were not eligible. The investigators from all eligible trials shared pseudonymised datasets, which were standardised and merged for analysis. The primary outcome was all-cause mortality during the intervention period. Analyses were performed in the modified intention-to-treat population, including all randomly assigned participants who contributed to the endpoint. Fixed-effects two-stage meta-analysis of risk ratios (RRs) was used to generate pooled effect estimates for mortality. Recurrent time-to-event data (readmissions or clinic visits) were analysed using one-stage mixed-effects Prentice-Williams-Peterson total-time models to obtain hazard ratios (HRs). This study is registered with PROSPERO, CRD42022308791. FINDINGS: Our search identified 91 articles, of which 78 were excluded by title and abstract, and a further ten did not meet eligibility criteria. Three double-blind, placebo-controlled trials, including 3663 children with severe anaemia, were included in the systematic review and meta-analysis; 3507 (95·7%) contributed to the modified intention-to-treat analysis. Participants received monthly sulfadoxine-pyrimethamine until the end of the malaria transmission season (mean 3·1 courses per child [range 1-6]; n=1085; The Gambia), monthly artemether-lumefantrine given at the end of weeks 4 and 8 post discharge (n=1373; Malawi), or monthly dihydroartemisinin-piperaquine given at the end of weeks 2, 6, and 10 post discharge (n=1049; Uganda and Kenya). During the intervention period, post-discharge malaria chemoprevention was associated with a 77% reduction in mortality (RR 0·23 [95% CI 0·08-0·70], p=0·0094, I2=0%) and a 55% reduction in all-cause readmissions (HR 0·45 [95% CI 0·36-0·56], p<0·0001) compared with placebo. The protective effect was restricted to the intervention period and was not sustained after the direct pharmacodynamic effect of the drugs had waned. The small number of trials limited our ability to assess heterogeneity, its sources, and publication bias. INTERPRETATION: In malaria-endemic Africa, post-discharge malaria chemoprevention reduces mortality and readmissions in recently discharged children recovering from severe anaemia. Post-discharge malaria chemoprevention could be a valuable strategy for the management of this group at high risk. Future research should focus on methods of delivery, options to prolong the protection duration, other hospitalised groups at high risk, and interventions targeting non-malarial causes of post-discharge morbidity. FUNDING: The Research-Council of Norway and the Bill-&-Melinda-Gates-Foundation through the Worldwide-Antimalarial-Research-Network.
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Anemia , Antimaláricos , Malaria , Niño , Humanos , Preescolar , Antimaláricos/uso terapéutico , Alta del Paciente , Cuidados Posteriores , Arteméter/uso terapéutico , Combinación Arteméter y Lumefantrina/uso terapéutico , Malaria/complicaciones , Malaria/epidemiología , Malaria/prevención & control , Anemia/epidemiología , Combinación de Medicamentos , Kenia , Quimioprevención , Ensayos Clínicos Controlados Aleatorios como AsuntoRESUMEN
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.
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Background: Cerebral malaria is the most severe neurological complication of Falciparum malaria. It is associated with a significant risk of death and neurological sequelae. A biphasic clinical picture is associated with an even greater risk of neurological sequelae. Objective:To examine the incidence and clinical characteristics of a biphasic clinical course in children with cerebral malaria and to study its relationship with outcome. Method : We undertook a retrospective study of children admitted to Kilifi District Hospital with a history of impaired consciousness and Falciparum infection between January 1994 and December 2004. We identified children with a biphasic clinical course and examined their clinical characteristics and outcome against that of those with a single clinical course. Results : Out of 587 children with cerebral malaria; 11 were found to have a biphasic clinical course often heralded by recurrence of seizures. This clinical pattern was associated with a greater incidence of neurological sequelae but no death. Conclusion: We speculate that a biphasic clinical course may occur due to recurrent seizures; co-morbidity and reperfusion of cerebral areas previously clogged by parasitized red blood cells. A prospective examination of this group may shed more light on causality and enlighten further on pathogenesis of cerebral malaria