One aspect of Central Nervous System (CNS) involvement in SARS-CoV2 infection that has attracted little interest so far is the medium or long-term consequences on patients with neurodegenerative diseases (NDD). It is known that chronic neuroinflammation has been associated with the neuropathophysiology of some NDDs such as multiple sclerosis, Parkinson disease, Alzheimer disease (AD), and others.2 In the case of AD, in presence of proinflammatory cytokines/chemokines, the microglia loses ability to phagocytize the Aβ protein, favoring the pathogenic deposits.3 Similar evidence exists in other NDD.4 The cytokine storm of SARS-CoV2 infection involves the activation of a neuroinflammatory cascade similar to that described in NDD.5 Furthermore, the possibility that this molecular movement may be persistent over time after acute infection is eliminated, in a similar way to what occurs in the so-called "Persistent Inflammation-immunosuppression and Catabolism Syndrome."5 Finally, we do not know whether SARS-CoV2 may have the ability to remain latent in the CNS in a similar way as other coronaviruses do,6 increasing the possibility of sustained neuroinflammation. The repercussion on the population vulnerable to NDD is unknown but will force us to be attentive to the future of our patients.
Neurologia (2020), doi: https://doi.org/10.1016/j.nrl.2020.04.002
Introduction: SARS-CoV-2 was first detected in December 2019 in the Chinese city of Wuhan and
has since spread across the world. At present, the virus has infected over 1.7 million people and
caused over 100 000 deaths worldwide. Research is currently focused on understanding the acute
infection and developing effective treatment strategies. In view of the magnitude of the
epidemic, we conducted a speculative review of possible medium- and long-term neurological
consequences of SARS-CoV-2 infection, with particular emphasis on neurodegenerative and
neuropsychiatric diseases of neuroinflammatory origin, based on the available evidence on
neurological symptoms of acute SARS-CoV-2 infection.
Development: We systematically reviewed the available evidence about the pathogenic
mechanisms of SARS-CoV-2 infection, the immediate and lasting effects of the cytokine storm on
the central nervous system, and the consequences of neuroinflammation for the central nervous
Conclusions: SARS-CoV-2 is a neuroinvasive virus capable of triggering a cytokine storm, with
persistent effects in specific populations. Although our hypothesis is highly speculative, the
impact of SARS-CoV-2 infection on the onset and progression of neurodegenerative and
neuropsychiatric diseases of neuroinflammatory origin should be regarded as the potential cause
of a delayed pandemic that may have a major public health impact in the medium to long term.
Cognitive and neuropsychological function should be closely monitored in COVID-19 survivors.
Keywords: COVID-19; SARS-CoV-2; neuroinflammation; neurodegenerative diseases;
neuropsychiatric diseases; Alzheimer disease; Parkinson’s disease; multiple sclerosis; cytokine