Infections may cause vasculitis, either due to pathogen invasion, exaggerated immune response, or immune dysregulation triggered by bacterial toxins or antigens Hyperinflammation in SIRS and sepsis leads to coagulopathy and a prothrombotic stateīoth direct pathogen invasion and the proinflammatory state of sepsis lead to endothelial damage, which then shifts to a procoagulant state and has increased vascular permeability Release of inflammatory mediators affecting both the BBB and the cerebral microcirculation (“cytokine storm”)Īcute haemorrhagic leukoencephalitis (AHL)Ĭan be isolated or in the context of sepsis and organ failure:Įlectrolyte imbalances (hyponatremia or hypernatremia, hypocalcaemia or hypercalcemia) Presents as impaired attention and arousal Invade the PNS by binding to receptors on axons of sensory, autonomic and motor neurons, including the olfactory and vagal nerves ĭiffuse disturbance of brain function as a consequence of the systemic inflammatory response of sepsis Move along peripheral nerves via retrograde (from axon terminal to cell body) or anterograde (from cell body to axon terminal) transport Peripheral nerves (trans-synaptic spread) Via entry of infected leukocytes from the peripheral circulation into the CNS (Trojan horse mechanism) Paracellular entry (by disrupting tight junctions) Transcellular penetration (using pinocytosis or receptor-mediated entry) Penetration of endothelial barriers via (BBB disruption associated with acute host inflammatory responses may facilitate invasion): This narrative review assesses the neurological manifestations of past and current pandemics, to aid our understanding of the current pandemic and prepare for future outbreaks.īlood brain barrier (BBB) (haematological entry) Understanding neurological complications of previous pandemics, and the pathophysiological mechanisms that underlie them, are fundamental to place the current situation in perspective, and help address the enduring consequences once current waves of acute infection subside. Aside from the associated mortality, neurological involvement of infectious disease can lead to prolonged hospital stay and significantly increase rehabilitation time and long-term care needs after discharge, posing a far-reaching socioeconomic burden.Īs the world deals with the Sars-CoV2 pandemic, reports of neurologic manifestations have increased. Even in tertiary centres of developed countries, up to 30% of patients with a CNS infection never receive an etiological diagnosis, and in low resource settings lacking diagnostic tools, neurological manifestations are often poorly characterised. The majority of pathogens responsible for outbreaks can cause neurologic illness, which are frequently overlooked, under-reported and under-diagnosed. Increase in global travel, urbanisation, climate change, environmental degradation, displacement and consumption of wild animals are factors thought to have increased the likelihood of pandemics during the past century. Pandemics are large-scale outbreaks of infectious disease that can cause an excess in morbidity and mortality globally, or at least over a wide geographic area, and lead to socio-economic disruption. 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. 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. Nervous system infection or dysfunction during pandemics is common and its enduring consequences, especially among vulnerable populations, are frequently forgotten. 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. Despite advances in the treatment of infectious diseases, nervous system involvement remains a challenge, with limited treatments often available. Neurological manifestations in pandemics frequently cause short and long-term consequences which are frequently overlooked.
0 kommentar(er)
