Cerebral malaria

Cerebral manifestations of falciparum malaria in adults: more than meets the eye

The application of neuroimaging techniques to patients with Plasmodium falciparum infection has uncovered a wide range of brain changes not only in cerebral malaria but also in noncomatose patients. We propose several hypotheses to unify findings across the spectrum of clinical malaria in adults and highlight the urgent need to evaluate potential long-term effects of cerebral alterations on neurocognition in this understudied age group.

Treatment of a patient with severe cerebral malaria during the COVID-19 pandemic in China: A case report

BACKGROUND

On June 30, 2021, China received certification from the World Health Organization for malaria elimination. However, this certification does not signify the absence of malaria within China. Due to the increasing frequency of international exchanges and collaborations, the threat of imported malaria persists in China. Consequently, the prevention and control of imported malaria have become a primary focus for our country to maintain its malaria elimination status.

CASE SUMMARY

Herein, we present a case report of a 53-year-old Chinese man who worked in Africa for nearly two years. He was diagnosed with malaria in the Democratic Republic of the Congo between November 19 and November 23, 2022. After receiving effective treatment with oral antimalarial drugs, his condition improved, allowing him to return to China. He was later admitted to our hospital on January 12, 2023, during the coronavirus disease 2019 pandemic in Huangshi, China. Through a thorough evaluation of the patient's symptoms, clinical signs, imaging and laboratory test results, and epidemiological data, he was rapidly diagnosed with severe cerebral malaria. The patient underwent successful treatment through a series of intensive care unit interventions.

CONCLUSION

The successful treatment of this imported case of severe cerebral malaria provides a valuable reference for managing patients with similar malaria infections and has significant clinical implications.

Neuroinfectious Diseases in Children: Pathophysiology, Outcomes, and Global Challenges

Pathogens with affinity for the central nervous system (CNS) in children are diverse in their mechanisms of infecting and attacking the brain. Infections can reach the CNS via hematogenous routes, transneurally thereby avoiding the blood-brain barrier, and across mucosal or skin surfaces. Once transmission occurs, pathogens can wreak havoc both by direct action on host cells and via an intricate interplay between the protective and pathologic actions of the host's immune system. Pathogen prevalence varies depending on region, and susceptibility differs based on epidemiologic factors such as age, immune status, and genetics. In addition, some infectious diseases are monophasic, whereas others may lie dormant for years, thereby causing a dynamic effect on outcomes. Outcomes in survivors are highly variable for each particular pathogen and depend on the vaccination and immune status of the patient as well as the speed by which the patient receives evidence-based treatments. Given pathogens cause communicable diseases that can cause morbidity and mortality on a population level when spread, the burden is often the greatest and the outcomes the worst in low-resource settings. Here we will focus on the most common infections with a propensity to affect a child's brain, the pathologic mechanisms by which they do so, and what is known about the developmental outcomes in children who are affected by these infections.

Understanding the mechanisms underlying the disruption of the blood-brain barrier in parasitic infections

Parasites have a significant impact on the neurological, cognitive, and mental well-being of humans, with a global population of over 1 billion individuals affected. The pathogenesis of central nervous system (CNS) injury in parasitic diseases remains limited, and prevention and control of parasitic CNS infections remain significant areas of research. Parasites, encompassing both unicellular and multicellular organisms, have intricate life cycles and possess the ability to infect a diverse range of hosts, including the human population. Parasitic illnesses that impact the central and peripheral nervous systems are a significant contributor to morbidity and mortality in low- to middle-income nations. The precise pathways through which neurotropic parasites infiltrate the CNS by crossing the blood-brain barrier (BBB) and cause neurological harm remain incompletely understood. Investigating brain infections caused by parasites is closely linked to studying neuroinflammation and cerebral impairment. The exact molecular and cellular mechanisms involved in this process remain incomplete, but understanding the exact mechanisms could provide insight into their pathogenesis and potentially reveal novel therapeutic targets. This review paper explores the underlying mechanisms involved in the development of neurological disorders caused by parasites, including parasite-derived elements, host immune responses, and modifications in tight junctions (TJs) proteins.

Etiologies and factors associated with mortality in patients with non-traumatic coma in a tertiary hospital in Bukavu, eastern Democratic Republic of the Congo

Non-traumatic coma (NTC) is a common medical condition often associated with poor outcomes. Identifying underlying causes is crucial for effective management and prognostication, particularly in resource-poor settings. This study aimed to identify the most common causes and prognostic factors of NTC in a tertiary hospital in Bukavu, in the eastern Democratic Republic of the Congo (DRC), using the Glasgow Coma Scale (GCS) as well as other simple and affordable clinical and paraclinical tools. This retrospective observational study included 219 consecutive patients admitted to the intensive care unit of the Provincial General Hospital of Bukavu between January 2016 and December 2018. Sociodemographic, clinical, and laboratory data were also collected. Bivariate and multivariate analyses were performed to identify different causes and factors associated with poor outcomes in these patients. The median age of the patients was 49 (interquartile range [IQR]: 33-61) years, and they were predominantly men (62.8%). The most common causes of NTC were stroke (25.7%), acute metabolic complications of diabetes (21.9%), and primary brain infections (meningoencephalitis, 16.0%; and cerebral malaria, 14.2%). The NTC-related in-hospital mortality rate was 35.2%. A high mortality was significantly and independently associated with a GCS<7 (adjusted odds ratio [OR]: 4.30, 95% confidence interval [CI]: 1.73-10.71), the presence of meningismus at clinical evaluation (adjusted odds ratio [aOR] 3.86, 95%CI: 1.41-10.55), oxygen saturation <90% (aOR 3.99, 95%CI: 1.71-9.28), the consumption of traditional herbal medicines prior to hospital admission (aOR 2.82, 95%CI: 1.16-6.86), and elevated serum creatinine (aOR 1.64, 95%CI: 1.17-2.29). In conclusion, clinical neurological examinations, along with simple and affordable paraclinical investigations, can provide sufficient information to determine the etiology of NTC and evaluate the prognosis of comatose patients, even in resource-poor settings. Physicians may use the GCS as a simple, reliable, and affordable tool to identify patients who require special attention and care.

The kidney-brain pathogenic axis in severe falciparum malaria

Severe falciparum malaria is a medical emergency and a leading cause of death and neurodisability in endemic areas. Common complications include acute kidney injury (AKI) and cerebral malaria, and recent studies have suggested links between kidney and brain dysfunction in Plasmodium falciparum infection. Here, we review these new findings and present the hypothesis of a pivotal pathogenic crosstalk between the kidneys and the brain in severe falciparum malaria. We highlight the evidence of a role for distant organ involvement in the development of cerebral malaria and subsequent neurocognitive impairment post-recovery, describe the challenges associated with current diagnostic shortcomings for both AKI and brain involvement in severe falciparum malaria, and explore novel potential therapeutic strategies.

Hospital-based surveillance of severe paediatric malaria in two malaria transmission ecological zones of Burkina Faso

BACKGROUND

In the current context of tailoring interventions to maximize impact, it is important that current data of clinical epidemiology guide public health programmes and health workers in the management of severe disease. This study aimed at describing the burden of severe malaria at hospital level in two areas with distinct malaria transmission intensity.

METHODS

A hospital-based surveillance was established in two regional hospitals located in two areas exposed to different malaria transmission. Data on paediatric severe malaria admissions were recorded using standardized methods from August 2017 to August 2018 with an interruption during the dry season from April to June 2018.

RESULTS

In total, 921 children with severe malaria cases were enrolled in the study. The mean age was 33.9 (± 1.3) and 36.8 (± 1.6) months in lower malaria transmission (LMT) and higher malaria transmission (HMT) areas (p = 0.15), respectively. The geometric mean of asexual P. falciparum density was significantly higher in the LMT area compared to the HMT area: 22,861 trophozoites/µL (95% CI 17,009.2-30,726.8) vs 11,291.9 trophozoites/µL (95% CI 8577.9-14,864.5). Among enrolled cases, coma was present in 70 (9.2%) participants. 196 patients (21.8%) presented with two or more convulsions episodes prior to admission. Severe anaemia was present in 448 children (49.2%). Other clinical features recorded included 184 (19.9%) cases of lethargy, 99 (10.7%) children with incoercible vomiting, 80 (8.9%) patients with haemoglobinuria, 43 (4.8%) children with severe hypoglycaemia, 37 (4.0%) cases where child was unable to drink/suck, 11 (1.2%) cases of patients with circulatory collapse/shock, and 8 cases (0.9%) of abnormal bleeding (epistaxis). The adjusted odds of presenting with coma, respiratory distress, haemoglobinuria, circulatory collapse/shock and hypoglycaemia were significantly higher (respectively 6.5 (95%CI 3.4-12.1); 1.8 (95%CI 1.0-3.2); 2.7 (95%CI 1.6-4.3); 5.9 (95%CI 1.3-27.9); 1.9 (95%CI 1.0-3.6)) in children living in the HMT area compared to those residing in the LMT area. Overall, forty-four children died during hospitalization (case fatality rate 5.0%) with the highest fatalities in children admitted with respiratory distress (26.0%) and those with hypoglycaemia (25.0%).

CONCLUSION

The study showed that children in the HMT area have a higher risk of presenting with coma, shock/dehydration, haemoglobinuria, hypoglycaemia, and respiratory distress. Case-fatality rate is higher among patients with respiratory distress or hypoglycaemia. Hospital surveillance provides a reliable and sustainable means to monitor the clinical presentation of severe malaria and tailor the training needs and resources allocation for case management.

Cerebral Malaria and Neuronal Implications of Plasmodium Falciparum Infection: From Mechanisms to Advanced Models

Reorganization of host red blood cells by the malaria parasite Plasmodium falciparum enables their sequestration via attachment to the microvasculature. This artificially increases the dwelling time of the infected red blood cells within inner organs such as the brain, which can lead to cerebral malaria. Cerebral malaria is the deadliest complication patients infected with P. falciparum can experience and still remains a major public health concern despite effective antimalarial therapies. Here, the current understanding of the effect of P. falciparum cytoadherence and their secreted proteins on structural features of the human blood-brain barrier and their involvement in the pathogenesis of cerebral malaria are highlighted. Advanced 2D and 3D in vitro models are further assessed to study this devastating interaction between parasite and host. A better understanding of the molecular mechanisms leading to neuronal and cognitive deficits in cerebral malaria will be pivotal in devising new strategies to treat and prevent blood-brain barrier dysfunction and subsequent neurological damage in patients with cerebral malaria.

Cerebral malaria induced by plasmodium falciparum: clinical features, pathogenesis, diagnosis, and treatment

Cerebral malaria (CM) caused by Plasmodium falciparum is a fatal neurological complication of malaria, resulting in coma and death, and even survivors may suffer long-term neurological sequelae. In sub-Saharan Africa, CM occurs mainly in children under five years of age. Although intravenous artesunate is considered the preferred treatment for CM, the clinical efficacy is still far from satisfactory. The neurological damage induced by CM is irreversible and lethal, and it is therefore of great significance to unravel the exact etiology of CM, which may be beneficial for the effective management of this severe disease. Here, we review the clinical characteristics, pathogenesis, diagnosis, and clinical therapy of CM, with the aim of providing insights into the development of novel tools for improved CM treatments.

Delayed presentation to hospital care is associated with sequelae but not mortality in children with cerebral malaria in Malawi

Background

Cerebral malaria is still a major cause of death in children in sub-Saharan Africa. Among survivors, debilitating neurological sequelae can leave children with permanent cognitive impairments and societal stigma, resulting in taxing repercussions for their families. This study investigated the effect of delay in presentation to medical care on outcome in children with cerebral malaria in Malawi.

Methods

This retrospective study included participants enrolled in a longstanding study of cerebral malaria between 2001 and 2021 and considered coma duration prior to arrival at hospital (with or without anti-malarial treatment), HIV status, blood lactate levels at admission and age as factors that could affect clinical outcome. Outcomes were categorized as full recovery, sequelae at the time of discharge, or death. A multinomial regression was fit and run controlling for coma duration, HIV status, lactate levels and age, to determine the association between each explanatory variable and outcome.

Results

A total of 1663 children with cerebral malaria, aged 6 months to 14 years were included. Longer coma duration (in hours) was associated with greater odds of developing sequelae (OR = 1.023, 95% CI 1.007–1.039, p = 0.006) but not death (OR = 1.00, 95% CI 0.986–1.015, p = 0.961). Younger age (in months) was also correlated with higher rates of sequelae, (OR = 0.990, 95% CI 0.983–0.997, p = 0.004) but not with increased mortality (OR = 0.998, 95% CI 0.993–1.003, p = 0.335). Blood lactate levels on admission were correlated with mortality (OR = 1.125, 95% CI 1.090–1.161, p < 0.001) but not associated with increased rates of sequelae (OR = 1.016, 95% CI 0.973–1.060, p = 0.475). Positive HIV status and treatment with an anti-malarial (artemisinin or non-artemisinin-based) prior to arrival at the hospital were not significantly associated with either adverse outcome.

Conclusions

In Malawian children with cerebral malaria, higher rates of sequelae were significantly associated with extended coma duration prior to admission and younger age. Mortality rates were correlated with increased lactate levels on admission. The differential effects of variables on clinical outcomes suggest that there may be different pathogenic pathways leading to sequelae and death. Actions taken by parents and health care professionals are critical in defining when patients arrive at hospital and determining their ultimate outcome.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12936-022-04080-2.

Changing spectrum of acute encephalitis syndrome in India and a syndromic approach

Acute encephalitis syndrome (AES) refers to an acute onset of fever and clinical neurological manifestation that includes mental confusion, disorientation, delirium, or coma, which may occur because of infectious or non-infectious causes. Cerebrospinal fluid (CSF) pleocytosis generally favors infectious etiology, and a normal CSF favors an encephalopathy or non-infectious AES. Among the infectious AES, viral, bacterial, rickettsial, fungal, and parasitic causes are the commonest. Geographical and seasonal clustering and other epidemiological characteristics are important in clinical decision making. Clinical markers like eschar, skin rash, myalgia, hepatosplenomegaly, thrombocytopenia, liver and kidney dysfunction, elevated serum CK, fronto-temporal or thalamic involvement on MRI, and anterior horn cell involvement are invaluable clues for the etiological diagnosis. Categorizing the AES cases into neurologic [Herpes simplex encephalitis (HSE), Japanese encephalitis (JE), and West Nile encephalitis (WNE)] and systemic (scrub typhus, malaria, dengue, and Chikungunya) helps in rational utilization of diagnostic and management resources. In neurological AES, cranial CT/MRI revealing frontotemporal lesion is consistent with HSE, and thalamic and basal ganglia lesions are consistent with JE. Cerebrospinal fluid nucleic acid detection test or IgM antibody for JE and HSE are confirmatory. Presence of frontotemporal involvement on MRI indicates acyclovir treatment pending virological confirmation. In systemic AES, CT/MRI, PCR for HSE and JE, and acyclovir therapy may not be useful, rather treatable etiologies such as malaria, scrub typhus, and leptospirosis should be looked for. If smear or antigen for malaria is positive, should receive antimalarial, if negative doxycycline and ceftriaxone should be started pending serological confirmation of scrub typhus, leptospira, or dengue. A syndromic approach of AES based on the prevalent infection in a geographical region may be developed, which may be cost-effective.

Efficacy and safety of dual intravenous artesunate plus quinine compared to intravenous artesunate for cerebral malaria in a triple blinded parallel multisite randomized controlled trial in Nigerian children: DUAL PAQ TRIAL Protocol

Background

Evidence exists as to the criticality of the first 24 h in the management of cerebral malaria. The morbidity and the mortality rate (35%) with the current intravenous monotherapy for the initial treatment of cerebral malaria are unacceptably high. Combination therapy and a shorter course of effective medication have been shown to improve outcomes in human participants in the treatment of other diseases. This study outlines a protocol to conduct a triple blinded parallel randomized controlled trial on cerebral malaria using dual intravenous medications compared to the current standard of monotherapy.

Methods

This is a parallel multi-site randomized controlled superiority triple blinded trial consisting of intravenous artesunate plus quinine and a control arm of intravenous artesunate only. Eligible and assenting children aged 6 months to 17 years will be recruited from 4 tertiary hospitals by random selection from the list of tertiary hospitals in Nigeria. Participants will be randomized and assigned in parallel into two arms using random numbers generated from GraphPad Prism (version 9) by a clinical pharmacologist who has no link with the investigators, the patients, or the statistician. The primary measurable outcome is survival at 12, 24, and 48 h post-randomization. A composite secondary outcome consists of the number of children that regained consciousness, parasitaemia and defervescence at 12 and 24 h post-randomization and haematological and inflammatory markers at 24 and 48 h post-randomization. Adverse events both solicited and unsolicited are recorded all through the study post-randomization. The study is approved by the State Research Ethics Review Committee. Data analysis will be performed in GraphPad Prism version 9.

Discussion

The outcome of this analysis will give insight into the efficacy and safety of dual intravenous antimalaria in the treatment of cerebral malaria among Nigerian children compared with the standard of care. The safety profile of this intervention will also be highlighted. This may help inform physicians on the optimal treatment for cerebral malaria to improve outcomes and reduce recrudescence and treatment failure.

Trial registration

Pan Africa Clinical Trial Registry PACTR202102893629864. 23/02/2021.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05634-6.

Parasitic Infections of the Nervous System

PURPOSE OF REVIEW

This article reviews how parasites affect the human nervous system, with a focus on four parasitic infections of major public health importance worldwide, two caused by protozoa (malaria and toxoplasmosis) and two by helminths (neurocysticercosis and schistosomiasis).

RECENT FINDINGS

Parasitic infections in humans are common, and many can affect the central nervous system where they may survive unnoticed or may cause significant pathology that can even lead to the death of the host. Neuroparasitoses should be considered in the differential diagnosis of neurologic lesions, particularly in individuals from endemic regions or those with a history of travel to endemic regions.

SUMMARY

Cerebral malaria is a significant cause of mortality, particularly in African children, in whom infected red blood cells affect the cerebral vessels, causing severe encephalopathy. Neurocysticercosis is the most common cause of acquired epilepsy worldwide and has varied clinical presentations, depending on the number, size, and location of the parasites in the nervous system as well as on the host's inflammatory response. Toxoplasmosis is distributed worldwide, affecting a significant proportion of the population, and may reactivate in patients who are immunosuppressed, causing encephalitis and focal abscesses. Schistosomiasis causes granulomatous lesions in the brain or the spinal cord.

The neurological sequelae of pandemics and epidemics

Neurological manifestations in pandemics frequently cause short and long-term consequences which are frequently overlooked. Despite advances in the treatment of infectious diseases, nervous system involvement remains a challenge, with limited treatments often available. The under-recognition of neurological manifestations may lead to an increase in the burden of acute disease as well as secondary complications with long-term consequences. Nervous system infection or dysfunction during pandemics is common and its enduring consequences, especially among vulnerable populations, are frequently forgotten. An improved understanding the possible mechanisms of neurological damage during epidemics, and increased recognition of the possible manifestations is fundamental to bring insights when dealing with future outbreaks. To reverse this gap in knowledge, we reviewed all the pandemics, large and important epidemics of human history in which neurological manifestations are evident, and described the possible physiological processes that leads to the adverse sequelae caused or triggered by those pathogens.

Pentafluoro-3-hydroxy-pent-2-en-1-ones Potently Inhibit FNT-Type Lactate Transporters from all Five Human-Pathogenic Plasmodium Species

The protozoan parasite Plasmodium falciparum causes the most severe and prevailing form of malaria in sub-Saharan Africa. Previously, we identified the plasmodial lactate transporter, PfFNT, a member of the microbial formate-nitrite transporter family, as a novel antimalarial drug target. With the pentafluoro-3-hydroxy-pent-2-en-1-ones, we discovered PfFNT inhibitors that potently kill P. falciparum parasites in vitro. Four additional human-pathogenic Plasmodium species require attention, that is, P. vivax, most prevalent outside of Africa, and the regional P. malariae, P. ovale and P. knowlesi. Herein, we show that the plasmodial FNT variants are highly similar in terms of protein sequence and functionality. The FNTs from all human-pathogenic plasmodia and the rodent malaria parasite were efficiently inhibited by pentafluoro-3-hydroxy-pent-2-en-1-ones. We further established a phenotypic yeast-based FNT inhibitor screen, and found very low compound cytotoxicity and monocarboxylate transporter 1 off-target activity on human cells, particularly of the most potent FNT inhibitor BH267.meta, allowing these compounds to proceed towards animal model malaria studies.

Intracranial Pressure and Brain Tissue Oxygen Neuromonitoring in Pediatric Cerebral Malaria

BACKGROUND

Pediatric cerebral malaria (CM) is a severe complication of Plasmodium falciparum that often leaves survivors with severe neurologic impairment. Increased intracranial pressure (ICP) as a result of cerebral edema has been identified as a major predictor of morbidity and mortality in CM. Past studies have demonstrated that survivors are more likely to have resolution of elevated ICP and that efficient management of ICP crises may lead to better outcomes. However, data on invasive brain tissue oxygen monitoring are unknown.

CASE DESCRIPTION

We report a case of a pediatric patient with cerebral malaria who developed encephalopathy and cerebral edema and describe the pathophysiology of this disease process with invasive ICP and brain tissue oxygen multimodality neuromonitoring. The utilization of both ICP and brain tissue oxygen monitoring allowed prompt diagnosis and successful treatment of severe intracranial hypertension and low brain tissue oxygenation crisis. The patient was discharged to home in good neurologic condition.

CONCLUSIONS

Multimodality neuromonitoring may be considered in pediatric patients who have cerebral edema and encephalopathy from CM.

Conduite à tenir devant un enfant fébrile au retour de voyage☆

Les pathologies le plus fréquentes au retour de voyage à l’étranger sont les infections gastro-intestinales, les maladies fébriles et les problèmes dermatologiques. L’évaluation d’un enfant fébrile de retour de voyage est clinique : vérification des antécédents et des vaccinations, recherche d’autres cas au contact, signes fonctionnels et physiques, caractéristiques du voyage. Un bilan paraclinique de débrouillage complète souvent l’évaluation pour une orientation syndromique. Si les causes de fièvre sont surtout cosmopolites, la gravité des pathologies exotiques doit les faire rechercher en priorité. Le paludisme doit être évoqué devant toute fièvre en provenance d’Afrique subsaharienne. Le diagnostic repose sur l’association d’un frottis sanguin et d’un test sensible (goutte épaisse, polymerase chain reaction [PCR]) ou d’un test de diagnostic rapide (pour Plasmodium [P ]. falciparum ). Les critères clinicobiologiques de gravité sont essentiels pour orienter et traiter le patient. En cas d’accès non compliqué à P. falciparum , le traitement repose sur une thérapie combinée à base d’artémisinine (ACT), artéméther-luméfantrine ou arténimol-pipéraquine. Les accès graves sont traités par l’artésunate intraveineux, puis un ACT oral. Dengue, chikungunya et infection à virus Zika ont des caractéristiques cliniques communes (association fièvre-éruption-arthralgies, traitement symptomatique). En cas de dengue, il faut surveiller l’apparition de signes d’alerte qui pourraient faire craindre une évolution péjorative. Le chikungunya est grave en cas de transmission per partum, avec un risque d’encéphalite néonatale. Chez l’enfant, le Zika est a- ou peu symptomatique. Mais en cas d’infection pendant une grossesse, le risque est celui d’une embryofœtopathie. Le diagnostic de ces arboviroses repose sur la PCR à la phase aiguë et la sérologie secondairement. La symptomatologie de la typhoïde est peu spécifique, justifiant la pratique d’hémocultures systématiques devant une fièvre du retour. Son traitement repose sur les céphalosporines de troisième génération ou la ciprofloxacine, mais les résistances augmentent. Au total, la diversité des étiologies d’une fièvre de retour et la gravité potentielle des infections importées imposent une réflexion sur le parcours de soins de ces patients, en particulier vis-à-vis du risque de fièvre hémorragique.

Neurological disorder and psychosocial aspects of cerebral malaria: what is new on its pathogenesis and complications? A minireview

Recently, malaria is remain considered as the most prevalent infectious disease, affecting the human health globally. High morbidity and mortality worldwide is often allied with cerebral malaria (CM) based disorders of the central nervous system, especially across many tropical and sub-tropical regions. These disorders are characterised by the infection of Plasmodium species, which leads to acute or chronic neurological disorders, even after having active/effective antimalarial drugs. Furthermore, even during the treatment, individual remain sensitive for neurological impairments in the form of decrease blood flow and vascular obstruction in brain including many more other changes. This review briefly explains and update on the epidemiology, burden of disease, pathogenesis and role of CM in neurological disorders with behaviour and function in mouse and human models. Moreover, the social stigma, which plays an important role in neurological disorders and a factor for assessing CM, is also discussed in this review.

Neurologic infections during pregnancy

Neurologic infections during pregnancy represent a significant cause of maternal and fetal morbidity and mortality. Immunologic alterations during pregnancy increase the susceptibility of the premature brain to damage. This chapter summarizes the epidemiology, pathophysiology, and clinical manifestations in the pregnant woman and the infant, and the diagnosis, treatment, and prevention of the major viral, parasitic, and bacterial infections known to affect pregnancy. These organisms include herpes virus, parvovirus, cytomegalovirus, varicella, rubella, Zika virus, toxoplasmosis, malaria, group B streptococcus, listeriosis, syphilis, and tuberculosis. There is an emphasis on the important differences in diagnosis, treatment, and fetal outcome between trimesters. An additional overview is provided on the spectrum of neurologic sequelae of an affected infant, which ranges from developmental delay to hydrocephalus and seizures.

Cerebral Plasmodium falciparum malaria: The role of PfEMP1 in its pathogenesis and immunity, and PfEMP1-based vaccines to prevent it

Malaria, a mosquito-borne infectious disease caused by parasites of the genus Plasmodium continues to be a major health problem worldwide. The unicellular Plasmodium-parasites have the unique capacity to infect and replicate within host erythrocytes. By expressing variant surface antigens Plasmodium falciparum has evolved to avoid protective immune responses; as a result in endemic areas anti-malaria immunity develops gradually over many years of multiple and repeated infections. We are studying the role of Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) expressed by asexual stages of P. falciparum responsible for the pathogenicity of severe malaria. The immunopathology of falciparum malaria has been linked to cyto-adhesion of infected erythrocytes to specific host receptors. A greater appreciation of the PfEMP1 molecules important for the development of protective immunity and immunopathology is a prerequisite for the rational discovery and development of a safe and protective anti-disease malaria vaccine. Here we review the role of ICAM-1 and EPCR receptor adhering falciparum-parasites in the development of severe malaria; we discuss our current research to understand the factors involved in the pathogenesis of cerebral malaria and the feasibility of developing a vaccine targeted specifically to prevent this disease.

Brain diseases in changing climate

Climate change is one of the biggest and most urgent challenges for the 21st century. Rising average temperatures and ocean levels, altered precipitation patterns and increased occurrence of extreme weather events affect not only the global landscape and ecosystem, but also human health. Multiple environmental factors influence the onset and severity of human diseases and changing climate may have a great impact on these factors. Climate shifts disrupt the quantity and quality of water, increase environmental pollution, change the distribution of pathogens and severely impacts food production - all of which are important regarding public health. This paper focuses on brain health and provides an overview of climate change impacts on risk factors specific to brain diseases and disorders. We also discuss emerging hazards in brain health due to mitigation and adaptation strategies in response to climate changes.

Conducta práctica ante un niño febril al regresar de un viaje

Las enfermedades más frecuentes al regresar de un viaje al extranjero son las infecciones gastrointestinales, las enfermedades febriles y los problemas dermatológicos. La evaluación de un niño febril al regreso de un viaje es clínica: verificación de los antecedentes y las vacunaciones, búsqueda de otros casos en contacto, signos funcionales y físicos, y características del viaje. Unas pruebas complementarias de rutina completan a menudo la evaluación para una orientación sindrómica. Si bien las causas de fiebre son, sobre todo, cosmopolitas, la gravedad de la enfermedad exótica obliga a buscarlas prioritariamente. El paludismo debe sospecharse ante una fiebre procedente de África subsahariana. El diagnóstico se basa en la asociación de un frotis sanguíneo y una prueba sensible (gota gruesa, reacción en cadena de la polimerasa [PCR]) o una prueba de diagnóstico rápido (para Plasmodium falciparum ). Los criterios clínico-biológicos de gravedad son esenciales para orientar y tratar al paciente. En caso de acceso no complicado por P. falciparum, el tratamiento se basa en un tratamiento combinado a base de artemisinina (ACT), arteméter-lumefantrina o artenimol-piperaquina. Los accesos graves se tratan con artesunato intravenoso, seguido de ACT oral. Dengue, chikungunya e infección por virus Zika tienen características clínicas comunes (fiebre-erupción-artralgias, tratamiento sintomático). En caso de dengue, conviene controlar la aparición de signos de alerta, que podrían hacer temer una evolución negativa. El chikungunya es grave en caso de transmisión en el parto, con un riesgo de encefalitis neonatal. En el niño, el Zika es asintomático o poco sintomático. Pero, en caso de infección durante el embarazo, el riesgo es el de una embriofetopatía. El diagnóstico de estas arbovirosis se basa en la PCR en la fase aguda y en la serología secundariamente. La sintomatología de la fiebre tifoidea es poco específica, lo cual justifica la práctica de hemocultivos sistemáticos ante una fiebre tras un viaje. Su tratamiento se basa en las cefalosporinas de tercera generación o el ciprofloxacino, pero las resistencias aumentan. En suma, la diversidad de las etiologías de una fiebre al regreso de un viaje y la potencial gravedad de las infecciones importadas imponen una reflexión sobre el proceso de tratamiento de estos pacientes, en especial en lo referente al riesgo de fiebre hemorrágica.

Infectious encephalitis: mimics and chameleons

Click here to listen to the Podcast 'Query encephalitis' is a common neurological consultation in hospitalised patients. Identifying the syndrome is only part of the puzzle. Although historically encephalitis has been almost synonymous with infection, we increasingly recognise parainfectious or postinfectious as well as other immune-mediated causes. We must also distinguish encephalitis from other causes of encephalopathy, including systemic infection, metabolic derangements, toxins, inherited metabolic disorders, hypoxia, trauma and vasculopathies. Here, we review the most important differential diagnoses (mimics) of patients presenting with an encephalitic syndrome and highlight some unusual presentations (chameleons) of infectious encephalitis.

A retinal model of cerebral malaria

Malaria is a causative factor in about 500.000 deaths each year world-wide. Cerebral malaria is a particularly severe complication of this disease and thus associated with an exceedingly high mortality. Malaria retinopathy is an ocular manifestation often associated with cerebral malaria, and presumably shares a substantial part of its pathophysiology. Here, we describe that indeed murine malaria retinopathy reproduced the main hallmarks of the corresponding human disease. In the living animal, we were able to follow the circulation and cellular localization of malaria parasites transgenically labelled with GFP via non-invasive in vivo retinal imaging. We found that malaria parasites cross the blood-retinal-barrier and infiltrate the neuroretina, concomitant with an extensive, irreversible, and long-lasting retinal neurodegeneration. Furthermore, anti-malarial treatment with dihydroartemisinin strongly diminished the load of circulating parasites but resolved the symptoms of the retinopathy only in part. In summary, we introduce here a novel preclinical model for human cerebral malaria that is much more directly accessible for studies into disease pathophysiology and development of novel treatment approaches. In vivo retinal imaging may furthermore serve as a valuable tool for the early diagnosis of the human disease.

Case Report: Probable Case of Spontaneous Encephalopathy Due to Loiasis and Dramatic Reduction of Loa loa Microfilariaemia with Prolonged Repeated Courses of Albendazole

Loiasis is a vector-borne parasitic disease caused by the filarial nematode Loa loa and transmitted by the tabanid vectors from the genus Chrysops. Loa loa infection is associated with clinical manifestations such as pruritus, migratory transient edema, passage of adult worm in the bulbar conjunctiva, retinal damage, glomerular damage, albuminuria, pleural effusion, hydrocele, and endomyocardial fibrosis. Data reporting the occurrence of spontaneous encephalopathy associated with loiasis are very scanty. Severe adverse events occurring post-ivermectin administered in the framework of the fight against onchocerciasis and/or lymphatic filariasis in loiasis co-endemic areas have been closely associated with very high L. loa microfilariaemia. Different regimens have been used to lower L. loa microfilariaemia before definitive treatment, and many discrepancies have been reported. We report the case of a patient who was admitted to a health facility and hospitalized for 34 days for altered consciousness, blurred vision, headache, and chills. After other potential diagnoses were eliminated, the patient was confirmed with encephalopathy due to loiasis and referred to the Centre for Research on Filariasis and other Tropical Diseases (CRFilMT). On admission at CRFilMT, the patient was harboring 28,700 microfilariae per milliliter of blood (mf/mL), and after four 21-day courses of 400 mg daily albendazole, the L. loa microfilariaemia lowered to 5,060 mf/mL. The patient was then treated with ivermectin 3 mg and a total clearance of microfilariae was observed, with satisfactory clinical evolution and no adverse event. This case study further confirmed that albendazole is effective against L. loa, but might necessitate a longer course.

Foot-and-mouth disease virus-like particles as integrin-based drug delivery system achieve targeting anti-tumor efficacy

The surface of foot-and-mouth disease virus (FMDV)-like particles (VLPs) contains a conserved arginine-glycine-aspartic acid (RGD) motif. Natural FMDV specifically attaches to overexpressed integrin receptors in several cancer cells. The FMDV VLPs produced in Escherichia coli were used for the first time as a delivery system of anti-tumor drug doxorubicin (DOX). The DOX-loaded VLPs exhibited a distinct release profile in different physiological conditions. The effects of FMDV-VLPs-DOX on cellular internalization and viability were evaluated in vitro by cell imaging, MTT assay and apoptosis, respectively. The anti-tumor efficacy in vivo was also determined in a nude mouse xenograft model based on tumor volume/weight and histological changes. The FMDV-VLPs-DOX complex significantly inhibited the proliferation of tumor and improved the pathological damage of DOX to non-targeting tissues. All results supported the potential of FMDV VLPs as a platform for specific targeted delivery of drugs or chemical reagents.

Psychiatric effects of malaria and anti-malarial drugs: historical and modern perspectives

The modern medical literature implicates malaria, and particularly the potentially fatal form of cerebral malaria, with a risk of neurocognitive impairment. Yet historically, even milder forms of malaria were associated in the literature with a broad range of psychiatric effects, including disorders of personality, mood, memory, attention, thought, and behaviour. In this article, the history of psychiatric effects attributed to malaria and post-malaria syndromes is reviewed, and insights from the historical practice of malariotherapy in contributing to understanding of these effects are considered. This review concludes with a discussion of the potentially confounding role of the adverse effects of anti-malarial drugs, particularly of the quinoline class, in the unique attribution of certain psychiatric effects to malaria, and of the need for a critical reevaluation of the literature in light of emerging evidence of the chronic nature of these adverse drug effects.

Tying malaria and microRNAs: from the biology to future diagnostic perspectives

Symptoms caused by bacterial, viral and malarial infections usually overlap and aetiologic diagnosis is difficult. Patient management in low-resource countries with limited laboratory services has been based predominantly on clinical evaluation and syndromic approaches. However, such clinical assessment has limited accuracy both for identifying the likely aetiological cause and for the early recognition of patients who will progress to serious or fatal disease. Plasma-detectable biomarkers that rapidly and accurately diagnose severe infectious diseases could reduce morbidity and decrease the unnecessary use of usually scarce therapeutic drugs. The discovery of microRNAs (miRNAs) has opened exciting new avenues to identify blood biomarkers of organ-specific injury. This review assesses current knowledge on the relationship between malaria disease and miRNAs, and evaluates how future research might lead to the use of these small molecules for identifying patients with severe malaria disease and facilitate treatment decisions.

Anesthetic management of urgent cesarean delivery in a parturient with acute malaria infection: a case report

Malaria is associated with high rates of morbidity and mortality worldwide, particularly in Africa, Southeast Asia and South America. Nonetheless, several cases of malaria have been reported in Western countries involving travelers from endemic areas, though very few involve pregnant women. In this article, we report a case of a young woman born in Sierra Leone who had been living in Italy for two years. She was admitted to our hospital with malaise; worsening of her condition led to Plasmodium falciparum infection diagnosis early during her hospital stay, as well as an urgent cesarean delivery. We briefly discuss the features of malaria in pregnancy, the difficulties associated with early diagnosis, and the possible fetal and maternal implications, and also consider how the disease may affect anesthetic management.

Extracellular hemoglobin: the case of a friend turned foe

Hemoglobin (Hb) is a highly conserved molecule present in all life forms and functionally tied to the complexity of aerobic organisms on earth in utilizing oxygen from the atmosphere and delivering to cells and tissues. This primary function sustains the energy requirements of cells and maintains cellular homeostasis. Decades of intensive research has presented a paradigm shift that shows how the molecule also functions to facilitate smooth oxygen delivery through the cardiovascular system for cellular bioenergetic homeostasis and signaling for cell function and defense. These roles are particularly highlighted in the binding of Hb to gaseous molecules carbon dioxide (CO₂), nitric oxide (NO) and carbon monoxide (CO), while also serving indirectly or directly as sources of these signaling molecules. The functional activities impacted by Hb outside of bioenergetics homeostasis, include fertilization, signaling functions, modulation of inflammatory responses for defense and cell viability. These activities are efficiently executed while Hb is sequestered safely within the confines of the red blood cell (rbc). Outside of rbc confines, Hb disaggregates and becomes a danger molecule to cell survival. In these perpectives, Hb function is broadly dichotomous, either a friend in its natural environment providing and facilitating the means for cell function or foe when dislocated from its habitat under stress or pathological condition disrupting cell function. The review presents insights into how this dichotomy in function manifests.

Montanide, Poly I:C and nanoparticle based vaccines promote differential suppressor and effector cell expansion: a study of induction of CD8 T cells to a minimal Plasmodium berghei epitope

The development of practical and flexible vaccines to target liver stage malaria parasites would benefit from an ability to induce high levels of CD8 T cells to minimal peptide epitopes. Herein we compare different adjuvant and carrier systems in a murine model for induction of interferon gamma (IFN-γ) producing CD8 T cells to the minimal immuno-dominant peptide epitope from the circumsporozoite protein (CSP) of Plasmodium berghei, pb9 (SYIPSAEKI, referred to as KI). Two pro-inflammatory adjuvants, Montanide and Poly I:C, and a non-classical, non-inflammatory nanoparticle based carrier (polystyrene nanoparticles, PSNPs), were compared side-by-side for their ability to induce potentially protective CD8 T cell responses after two immunizations. KI in Montanide (Montanide + KI) or covalently conjugated to PSNPs (PSNPs-KI) induced such high responses, whereas adjuvanting with Poly I:C or PSNPs without conjugation was ineffective. This result was consistent with an observed induction of an immunosuppressed environment by Poly I:C in the draining lymph node (dLN) 48 h post injection, which was reflected by increased frequencies of myeloid derived suppressor cells (MDSCs) and a proportion of inflammation reactive regulatory T cells (Treg) expressing the tumor necrosis factor receptor 2 (TNFR2), as well as decreased dendritic cell (DC) maturation. The other inflammatory adjuvant, Montanide, also promoted proportional increases in the TNFR2⁺ Treg subpopulation, but not MDSCs, in the dLN. By contrast, injection with non-inflammatory PSNPs did not cause these changes. Induction of high CD8 T cell responses, using minimal peptide epitopes, can be achieved by non-inflammatory carrier nanoparticles, which in contrast to some conventional inflammatory adjuvants, do not expand either MDSCs or inflammation reactive Tregs at the site of priming.

Cerebral malaria as a risk factor for the development of epilepsy and other long-term neurological conditions: a meta-analysis

Cerebral malaria (CM) is the most common and severe acute neurological manifestation of Plasmodium falciparum malaria. Children living in malaria-endemic areas of sub-Saharan Africa are at the highest risk of developing CM, and the long-term effect of CM on neurological function is uncertain. We conducted a meta-analysis to quantitatively assess the association between CM and development of long-term neurological impairment. We performed a systematic search through PubMed (including MEDLINE; 1946 to December 2014) and EMBASE (1974 to January 2015) to identify relevant articles. Eligible studies assessed the association between CM and neurological sequelae and were included if they met the criteria allowing a complete extraction of data. Eight studies were included in the final analysis, and in total, 2005 individuals were analysed (cases: n=842, controls: n=1163), most of whom were children. CM was associated with an increased risk of epilepsy (OR 4.68, 95% CI: 2.52-8.70), an increased risk of intelligence quotient (IQ) impairment (OR 4.72, 95% CI: 0.78-28.49), an increased risk of neurodisabilities (OR 16.16, 95% CI: 1.34-195.45), and an increased risk of behavioural disorder (OR 8.47, 95% CI: 2.75-26.04). Our findings suggest that children who survive CM are at increased risk of long-term neurological adverse outcome, including epilepsy. This may present a major public health problem in terms of education and development in malaria-endemic areas. Measures to avoid neurological morbidity are warranted.

Pathogenesis of cerebral malaria--inflammation and cytoadherence

Despite decades of research on cerebral malaria (CM) there is still a paucity of knowledge about what actual causes CM and why certain people develop it. Although sequestration of P. falciparum infected red blood cells has been linked to pathology, it is still not clear if this is directly or solely responsible for this clinical syndrome. Recent data have suggested that a combination of parasite variant types, mainly defined by the variant surface antigen, P. falciparum erythrocyte membrane protein 1 (PfEMP1), its receptors, coagulation and host endothelial cell activation (or inflammation) are equally important. This makes CM a multi-factorial disease and a challenge to unravel its causes to decrease its detrimental impact.