Protocol for a magnetic resonance imaging study of participants in the fever RCT: Does fever control prevent brain injury in malaria?

BACKGROUND: Despite eradication efforts, ~135,000 African children sustained brain injuries as a result of central nervous system (CNS) malaria in 2021. Newer antimalarial medications rapidly clear peripheral parasitemia and improve survival, but mortality remains high with no associated decline in post-malaria neurologic injury. A randomized controlled trial of aggressive antipyretic therapy with acetaminophen and ibuprofen (Fever RCT) for malarial fevers being conducted in Malawi and Zambia began enrollment in 2019. We propose to use neuroimaging in the context of the RCT to further evaluate neuroprotective effects of aggressive antipyretic therapy. METHODS: This observational magnetic resonance imaging (MRI) ancillary study will obtain neuroimaging and neurodevelopmental and behavioral outcomes in children previously enrolled in the Fever RCT at 1- and 12-months post discharge. Analysis will compare the odds of any brain injury between the aggressive antipyretic therapy and usual care groups based upon MRI structural abnormalities. For children unable to undergo imaging without deep sedation, neurodevelopmental and behavioral outcomes will be used to identify brain injury. DISCUSSION: Neuroimaging is a well-established, valid proxy for neurological outcomes after brain injury in pediatric CNS malaria. This MRI ancillary study will add value to the Fever RCT by determining if treatment with aggressive antipyretic therapy is neuroprotective in CNS malaria. It may also help elucidate the underlying mechanism(s) of neuroprotection and expand upon FEVER RCT safety assessments.

Protocol for a Magnetic Resonance Imaging (MRI) Study of Participants in the Fever Randomized Controlled Trial: Does fever control prevent brain injury in malaria?

Background: Despite eradication efforts, ~135,000 African children sustained brain injuries as a result of central nervous system (CNS) malaria in 2021. Newer antimalarial medications rapidly clear peripheral parasitemia and improve survival, but mortality remains high with no associated decline in post-malaria neurologic injury. A randomized controlled trial of aggressive antipyretic therapy with acetaminophen and ibuprofen (Fever RCT) for malarial fevers being conducted in Malawi and Zambia began enrollment in 2019. We propose to use neuroimaging in the context of the RCT to further evaluate neuroprotective effects of aggressive antipyretic therapy. Methods: This observational magnetic resonance imaging (MRI) ancillary study will obtain neuroimaging and neurodevelopmental and behavioral outcomes in children previously enrolled in the Fever RCT at 1- and 12-months post discharge. Analysis will compare the odds of any brain injury between the aggressive antipyretic therapy and usual care groups based upon MRI structural abnormalities. For children unable to undergo imaging without deep sedation, neurodevelopmental and behavioral outcomes will be used to identify brain injury. Discussion: Neuroimaging is a well-established, valid proxy for neurological outcomes after brain injury in pediatric CNS malaria. This MRI ancillary study will add value to the Fever RCT by determining if treatment with aggressive antipyretic therapy is neuroprotective in CNS malaria. It may also help elucidate the underlying mechanism(s) of neuroprotection and expand upon FEVER RCT safety assessments.

Parasite histones are toxic to brain endothelium and link blood barrier breakdown and thrombosis in cerebral malaria.

Microvascular thrombosis and blood-brain barrier (BBB) breakdown are key components of cerebral malaria (CM) pathogenesis in African children and are implicated in fatal brain swelling. How Plasmodium falciparum infection causes this endothelial disruption and why this occurs, particularly in the brain, is not fully understood. In this study, we have demonstrated that circulating extracellular histones, equally of host and parasite origin, are significantly elevated in CM patients. Higher histone levels are associated with brain swelling on magnetic resonance imaging. On postmortem brain sections of CM patients, we found that histones are colocalized with P falciparum-infected erythrocytes sequestered inside small blood vessels, suggesting that histones might be expelled locally during parasite schizont rupture. Histone staining on the luminal vascular surface colocalized with thrombosis and leakage, indicating a possible link between endothelial surface accumulation of histones and coagulation activation and BBB breakdown. Supporting this, patient sera or purified P falciparum histones caused disruption of barrier function and were toxic to cultured human brain endothelial cells, which were abrogated with antihistone antibody and nonanticoagulant heparin. Overall, our data support a role for histones of parasite and host origin in thrombosis, BBB breakdown, and brain swelling in CM, processes implicated in the causal pathway to death. Neutralizing histones with agents such as nonanticoagulant heparin warrant exploration to prevent brain swelling in the development or progression of CM and thereby to improve outcomes.

Nontraumatic Myelopathy in Malawi: A Prospective Study in an Area with High HIV Prevalence.

Nontraumatic myelopathy causes severe morbidity and is not uncommon in Africa. Clinically, patients often present with paraplegia, and extrinsic cord compression and transverse myelitis are most common causes. Data on exact pathogenesis are scanty because of limitations in diagnostic methods. In Queen Elizabeth Central Hospital, Blantyre, Malawi, we recorded consecutive patients presenting with nontraumatic paraplegia for maximally 6 months between January and July 2010 and from March to December 2011. The diagnostic workup included imaging and examining blood, stool, urine, sputum, and cerebrospinal fluid (CSF) samples for infection. After discharge, additional diagnostic tests, including screening for virus infections, borreliosis, syphilis, and schistosomiasis, were carried out in the Netherlands. The clinical diagnosis was, thus, revised in retrospect with a more accurate final differential diagnosis. Of 58 patients included, the mean age was 41 years (range, 12-83 years) and the median time between onset and presentation was 18 days (range, 0-121 days), and of 55 patients tested, 23 (42%) were HIV positive. Spinal tuberculosis (n = 24, 41%), tumors (n = 16, 28%), and transverse myelitis (n = 6, 10%) were most common; in six cases (10%), no diagnosis could be made. The additional tests yielded evidence for CSF infection with Schistosoma, Treponema pallidum, Epstein-Barr virus (EBV), HHV-6, HIV, as well as a novel cyclovirus. The diagnosis of the cause of paraplegia is complex and requires access to an magnetic resonance imaging (MRI) scan and other diagnostic (molecular) tools to demonstrate infection. The major challenge is to confirm the role of detected pathogens in the pathophysiology and to design an effective and affordable diagnostic approach.

Neurodevelopmental Impairments 1 Year After Cerebral Malaria.

: media-1vid110.1542/5972295739001PEDS-VA_2018-1026Video Abstract BACKGROUND AND OBJECTIVES: Cerebral malaria (CM) causes significant mortality and morbidity in sub-Saharan African children. Reliable morbidity estimates are scarce because of methodological variability across studies. We describe the incidence, course, and severity of neurodevelopmental impairments in survivors of CM and the associated patient characteristics to inform epidemiologic estimates of malaria morbidity rates and prevention and treatment efforts. METHODS: We conducted an exposure-control study of 85 survivors of CM and 100 age-matched patients in a control group who were enrolled at hospital discharge and assessed after 1, 6, and 12 months using caregiver interviews and standardized developmental, cognitive, and behavioral measures. RESULTS: Developmental or cognitive impairment (<10th percentile of the control distribution) and/or new onset of caregiver-reported behavior problems occurred in 53% of case patients compared with 20% of the patients in the control group (odds ratio 4.5; 95% CI: 2.4 to 8.6; P < .001). In case patients, developmental or cognitive impairment at the 12-month assessment was associated with HIV-positive status and short stature at presentation, more prolonged fever and coma during admission, and severe atrophy or multifocal abnormalities being found on MRI at the 1-month assessment. CONCLUSIONS: One-half of survivors of CM were neurodevelopmentally impaired at the 1-year assessment. With these results, we support prevention trials of acute, neuroprotective interventions and the allocation of resources to evaluation, education, and rehabilitation efforts to reduce the significant long-term burden of CM-associated impairments on families and their communities.

Brain swelling is independent of peripheral plasma cytokine levels in Malawian children with cerebral malaria.

BACKGROUND: Cerebral malaria (CM) is often fatal, and severe brain swelling is a predictor of CM-related mortality. CM is characterized by elevated circulating pro-inflammatory cytokines TNF and IFN-γ and anti-inflammatory cytokine IL-10, however whether cytokine levels correlate with brain swelling severity is unknown. This study therefore was conducted to investigate the relationship between cytokine levels and brain swelling severity in children presenting with CM. METHODS: A total of 195 Malawian children presenting with CM were recruited and had the concentrations of plasma cytokines determined and compared to brain swelling severity, determined by MRI examination, and graded as severe, moderate, mild or none. RESULTS: Levels of IL-1ß, IL-6, IL-8 and IL-10 did not differ between CM patients with and without severe brain swelling. Compared to children without brain swelling, IL-12 levels were higher in children with severe swelling (p < 0.01, no swelling 1 pg/mL, IQR [1] vs. severe swelling 18.7 pg/mL, IQR [1-27]), whereas TNF concentrations were higher in children with moderate brain swelling compared to children with no swelling (p < 0.01, no swelling 3 pg/mL, IQR [1-20] vs. moderate swelling 24 pg/mL, IQR [8-58]. Multivariate analysis showed that no single cytokine independently predicted brain swelling. CONCLUSION: Severe brain swelling in paediatric CM was independent of tested blood pro-inflammatory and anti-inflammatory cytokines which are markers of systemic inflammation.

Linking EPCR-Binding PfEMP1 to Brain Swelling in Pediatric Cerebral Malaria.

Brain swelling is a major predictor of mortality in pediatric cerebral malaria (CM). However, the mechanisms leading to swelling remain poorly defined. Here, we combined neuroimaging, parasite transcript profiling, and laboratory blood profiles to develop machine-learning models of malarial retinopathy and brain swelling. We found that parasite var transcripts encoding endothelial protein C receptor (EPCR)-binding domains, in combination with high parasite biomass and low platelet levels, are strong indicators of CM cases with malarial retinopathy. Swelling cases presented low platelet levels and increased transcript abundance of parasite PfEMP1 DC8 and group A EPCR-binding domains. Remarkably, the dominant transcript in 50% of swelling cases encoded PfEMP1 group A CIDRα1.7 domains. Furthermore, a recombinant CIDRα1.7 domain from a pediatric CM brain autopsy inhibited the barrier-protective properties of EPCR in human brain endothelial cells in vitro. Together, these findings suggest a detrimental role for EPCR-binding CIDRα1 domains in brain swelling.

The Role of Human Immunodeficiency Virus-Associated Vasculopathy in the Etiology of Stroke.

Background: Human immunodeficiency virus (HIV) infection is a recognized risk factor for stroke among young populations, but the exact mechanisms are poorly understood. We studied the clinical, radiologic, and histologic features of HIV-related ischemic stroke to gain insight into the disease mechanisms. Methods: We conducted a prospective, in-depth analysis of adult ischemic stroke patients presenting to Queen Elizabeth Central Hospital, Blantyre, Malawi, in 2011. Results: We recruited 64 HIV-infected and 107 HIV-uninfected patients. Those with HIV were significantly younger (P < .001) and less likely to have established vascular risk factors. Patients with HIV were more likely to have large artery disease (21% vs 10%; P < .001). The commonest etiology was HIV-associated vasculopathy (24 [38%]), followed by opportunistic infections (16 [25%]). Sixteen of 64 (25%) had a stroke soon after starting antiretroviral therapy (ART), suggesting an immune reconstitution-like syndrome. In this group, CD4+ T-lymphocyte count was low, despite a significantly lower HIV viral load in those recently started on treatment (P < .001). Conclusions: HIV-associated vasculopathy and opportunistic infections are common causes of HIV-related ischemic stroke. Furthermore, subtypes of HIV-associated vasculopathy may manifest as a result of an immune reconstitution-like syndrome after starting ART. A better understanding of this mechanism may point toward new treatments.

Cognitive Outcomes and Psychiatric Symptoms of Retinopathy-Positive Cerebral Malaria: Cohort Description and Baseline Results.

Cerebral malaria (CM) is a common cause of death and disability among children in sub-Saharan Africa. Many prior studies of neuropsychiatric morbidity have been limited by a cross-sectional design or a short duration of follow-up. Most have included subjects who may have presented with coma due to a disease process other than CM. No studies have assessed the relationship between magnetic resonance imaging (MRI) findings and long-term outcomes. The Cognitive Outcomes and Psychiatric symptoms of retinopathy-positive CM (COPS) cohort is the first large (N = 221) prospectively recruited cohort of stringently defined cases of CM and hospital-based, age-matched, non-CM controls in whom cognitive and psychiatric outcomes are assessed with standardized measures semi-annually for up to 5 years. We report baseline characteristics of the cohort and outcomes at 1 month. At enrollment, CM cases were more likely to come from families with fewer socioeconomic resources and to have health characteristics that increase risk for malaria. In children younger than 5 years, cases were delayed in motor, language, and social development by approximately 6 months, compared with controls. More significant delays occurred in those with MRI abnormalities at the 1-month follow-up visit. There were no differences between cases and controls in inhibitory self-control, nor in cognitive function in children ≥ 5 years of age. The latter finding may be related to the smaller sample size, case-control imbalance in socioeconomic status, or the use of cognitive and behavioral assessments that are less culturally appropriate to this population. Continued follow-up will help determine predictors of long-term outcomes.

Magnetic Resonance Imaging of Cerebral Malaria Patients Reveals Distinct Pathogenetic Processes in Different Parts of the Brain.

The mechanisms underlying the rapidly reversible brain swelling described in patients with cerebral malaria (CM) are unknown. Using a 1.5-Tesla (T) magnetic resonance imaging (MRI) scanner, we undertook an observational study in Rourkela, India, of 11 Indian patients hospitalized with CM and increased brain volume. Among the 11 cases, there were 5 adults and 6 children. All patients had reduced consciousness and various degrees of cortical swelling at baseline. The latter was predominately posterior in distribution. The findings on diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) maps were consistent with vasogenic edema in all cases. Reversibility after 48 to 72 h was observed in >90% of cases. DWI/ADC mismatch suggested the additional presence of cytotoxic edema in the basal nuclei of 5 patients; all of these had perfusion parameters consistent with vascular engorgement and not with ischemic infarcts. Our results suggest that an impairment of the blood-brain barrier is responsible for the brain swelling in CM. In 5 cases, vasogenic edema occurred in conjunction with changes in the basal nuclei consistent with venous congestion, likely to be caused by the sequestration of Plasmodium falciparum-infected erythrocytes. While both mechanisms have been individually postulated to play an important role in the development of CM, this is the first demonstration of their concurrent involvement in different parts of the brain. The clinical and radiological characteristics observed in the majority of our patients are consistent with posterior reversible encephalopathy syndrome (PRES), and we show for the first time a high frequency of PRES in the context of CM. IMPORTANCE The pathophysiology and molecular mechanisms underlying cerebral malaria (CM) are still poorly understood. Recent neuroimaging studies demonstrated that brain swelling is a common feature in CM and a major contributor to death in pediatric patients. Consequently, determining the precise mechanisms responsible for this swelling could open new adjunct therapeutic avenues in CM patients. Using an MRI scanner with a higher resolution than the ones used in previous reports, we identified two distinct origins of brain swelling in both adult and pediatric patients from India, occurring in distinct parts of the brain. Our results support the hypothesis that both endothelial dysfunction and microvascular obstruction by Plasmodium falciparum-infected erythrocytes make independent contributions to the pathogenesis of CM, providing opportunities for novel therapeutic interventions.

Safety of lumbar puncture in comatose children with clinical features of cerebral malaria.

OBJECTIVE: We assessed the independent association of lumbar puncture (LP) and death in Malawian children admitted to the hospital with the clinical features of cerebral malaria (CM). METHODS: This was a retrospective cohort study in Malawian children with clinical features of CM. Allocation to LP was nonrandom and was associated with severity of illness. Propensity score-based analyses were used to adjust for this bias and assess the independent association between LP and mortality. RESULTS: Data were available for 1,075 children: 866 (80.6%) underwent LP and 209 (19.4%) did not. Unadjusted mortality rates were lower in children who underwent LP (15.3% vs 26.7% in the no-LP group) but differences in covariates between the 2 groups suggested bias in LP allocation. After propensity score matching, all covariates were balanced. Propensity score-based analyses showed no change in mortality rate associated with LP: by inverse probability weighting, the average risk reduction was 2.0% at 12 hours (95% confidence interval -1.5% to 5.5%, p = 0.27) and 1.7% during hospital admission (95% confidence interval -4.5% to 7.9%, p = 0.60). Undergoing LP did not change the risk of mortality in subanalyses of children with severe brain swelling on MRI or in those with papilledema. CONCLUSION: In comatose children with suspected CM who were clinically stable, we found no evidence that LP increases mortality, even in children with objective signs of raised intracranial pressure.

HIV, antiretroviral treatment, hypertension, and stroke in Malawian adults: A case-control study.

OBJECTIVE: To investigate HIV, its treatment, and hypertension as stroke risk factors in Malawian adults. METHODS: We performed a case-control study of 222 adults with acute stroke, confirmed by MRI in 86%, and 503 population controls, frequency-matched for age, sex, and place of residence, using Global Positioning System for random selection. Multivariate logistic regression models were used for case-control comparisons. RESULTS: HIV infection (population attributable fraction [PAF] 15%) and hypertension (PAF 46%) were strongly linked to stroke. HIV was the predominant risk factor for young stroke (≤45 years), with a prevalence of 67% and an adjusted odds ratio (aOR) (95% confidence interval) of 5.57 (2.43-12.8) (PAF 42%). There was an increased risk of a stroke in patients with untreated HIV infection (aOR 4.48 [2.44-8.24], p < 0.001), but the highest risk was in the first 6 months after starting antiretroviral therapy (ART) (aOR 15.6 [4.21-46.6], p < 0.001); this group had a lower median CD4(+) T-lymphocyte count (92 vs 375 cells/mm(3), p = 0.004). In older participants (HIV prevalence 17%), HIV was associated with stroke, but with a lower PAF than hypertension (5% vs 68%). There was no interaction between HIV and hypertension on stroke risk. CONCLUSIONS: In a population with high HIV prevalence, where stroke incidence is increasing, we have shown that HIV is an important risk factor. Early ART use in immunosuppressed patients poses an additional and potentially treatable stroke risk. Immune reconstitution inflammatory syndrome may be contributing to the disease mechanisms.

Brain MRI of children with retinopathy-negative cerebral malaria.

Our goals were to understand the brain magnetic resonance imaging (MRI) findings in children with retinopathy-negative cerebral malaria (CM) and investigate whether any findings on acute MRI were associated with adverse outcomes. We performed MRI scans on children admitted to the hospital in Blantyre, Malawi with clinically defined CM. Two hundred and seventeen children were imaged during the study period; 44 patients were malarial retinopathy-negative; and 173 patients were retinopathy-positive. We compared MRI findings in children with retinopathy-negative and retinopathy-positive CM. In children who were retinopathy-negative, we identified MRI variables that were associated with death and adverse neurologic outcomes. On multivariate analysis, cortical diffusion weighted imaging (DWI) abnormality and increased brain volume were strongly associated with neurologic morbidity in survivors. Investigations to explore the underlying pathophysiologic processes responsible for these MRI changes are warranted.

Magnetic resonance imaging during life: the key to unlock cerebral malaria pathogenesis?

Understanding the mechanisms underlying the pathophysiology of cerebral malaria in patients with Plasmodium falciparum infection is necessary to implement new curative interventions. While autopsy-based studies shed some light on several pathological events that are believed to be crucial in the development of this neurologic syndrome, their investigative potential is limited and has not allowed the identification of causes of death in patients who succumb to it. This can only be achieved by comparing features between patients who die from cerebral malaria and those who survive. In this review, several alternative approaches recently developed to facilitate the comparison of specific parameters between fatal, non-fatal cerebral malaria and uncomplicated malaria patients are described, as well as their limitations. The emergence of neuroimaging as a revolutionary tool in identifying critical structural and functional modifications of the brain during cerebral malaria is discussed and highly promising areas of clinical research using magnetic resonance imaging are highlighted.

Utilization of ultrasound in medical inpatients in Malawi.

BACKGROUND: Ultrasound utilization studies in the developing world are important to support appropriate use. METHODS: A prospective, cross-sectional study in the medical wards at Queen Elizabeth Central Hospital, Blantyre, Malawi, was performed which aimed to assess referrals, reports and usefulness of scans to develop local recommendations. The primary outcome of a 'useful scan' was based on scan results and utilization of the report. Indication, quality of requests and reports, and operator were documented. Recommendations for request and report writing were developed. RESULTS: During 28 April-1 June 2011, 96 scans were analysed of which 66 (69%) were useful. Scans were not useful when the report was non-diagnostic, not documented or not acted upon. Seventy-eight scans (82%) were requested without prior laboratory investigations. A working diagnosis of a pericardial effusion was significantly associated with a useful scan (p = 0.01) as was a medical history of HIV (p ≤ 0.001). The quality of requests and reports in terms of clinical information was moderate or poor in 73% and 33% of cases respectively. Scans by clinicians were at greater odds (OR = 4.0, p = 0.01) of being useful compared with those by radiology technicians. CONCLUSION: Despite the majority of ultrasound scans being useful, underutilization and non-useful scans were common, indicating the need to identify appropriate indications and develop relevant guidance and training.

MRI findings in a cohort of brain injured survivors of pediatric cerebral malaria.

Abstract. A prospective cohort study of retinopathy-confirmed cerebral malaria (CM) survivors identified 42 of 132 with neurologic sequelae. The 38 survivors with sequelae who were alive when magnetic resonance imaging (MRI) technology became available underwent brain MRIs. Common MRI abnormalities included periventricular T2 signal changes (53%), atrophy (47%), subcortical T2 signal changes (18%), and focal cortical defects (16%). The χ(2) tests assessed the relationship between chronic MRI findings, acute clinical and demographic data, and outcomes. Children who were older at the time of CM infection (P = 0.01) and those with isolated behavioral problems (P = 0.02) were more likely to have a normal MRI. Acute focal seizures were associated with atrophy (P = 0.05). Acute papilledema was associated with subcortical T2 signal changes (P = 0.02). Peripheral retinal whitening (P = 0.007) and a higher admission white blood cell count (P = 0.02) were associated with periventricular T2 signal changes. Chronic MRI findings suggest seizures, increased intracranial pressure, and microvascular ischemia contribute to clinically relevant structural brain injury in CM.

SIOP PODC: clinical guidelines for the management of children with Wilms tumour in a low income setting.

Wilms tumour is a relatively common and curable paediatric tumour. Known challenges to cure in low income countries are late presentation with advanced disease, malnutrition, failure to complete treatment and limited facilities. In this article, management recommendations are given for a low income setting where only the minimal requirements for treatment with curative intent are available (setting 1). These include general management, supportive care, social support and registration of patients. Recommendations specific for Wilms tumour care include diagnostic procedures with emphasis on the role of ultrasonography, preoperative chemotherapy with a reduced dosage for malnourished children and postoperative chemotherapy based on surgical staging.

Neurologic manifestations associated with an outbreak of typhoid fever, Malawi--Mozambique, 2009: an epidemiologic investigation.

BACKGROUND: The bacterium Salmonella enterica serovar Typhi causes typhoid fever, which is typically associated with fever and abdominal pain. An outbreak of typhoid fever in Malawi-Mozambique in 2009 was notable for a high proportion of neurologic illness. OBJECTIVE: Describe neurologic features complicating typhoid fever during an outbreak in Malawi-Mozambique METHODS: Persons meeting a clinical case definition were identified through surveillance, with laboratory confirmation of typhoid by antibody testing or blood/stool culture. We gathered demographic and clinical information, examined patients, and evaluated a subset of patients 11 months after onset. A sample of persons with and without neurologic signs was tested for vitamin B6 and B12 levels and urinary thiocyanate. RESULTS: Between March - November 2009, 303 cases of typhoid fever were identified. Forty (13%) persons had objective neurologic findings, including 14 confirmed by culture/serology; 27 (68%) were hospitalized, and 5 (13%) died. Seventeen (43%) had a constellation of upper motor neuron findings, including hyperreflexia, spasticity, or sustained ankle clonus. Other neurologic features included ataxia (22, 55%), parkinsonism (8, 20%), and tremors (4, 10%). Brain MRI of 3 (ages 5, 7, and 18 years) demonstrated cerebral atrophy but no other abnormalities. Of 13 patients re-evaluated 11 months later, 11 recovered completely, and 2 had persistent hyperreflexia and ataxia. Vitamin B6 levels were markedly low in typhoid fever patients both with and without neurologic signs. CONCLUSIONS: Neurologic signs may complicate typhoid fever, and the diagnosis should be considered in persons with acute febrile neurologic illness in endemic areas.