Neurological Complications of COVID-19: A Systematic Review of Literature

Background: To study the nature and frequency of occurrence of “significant” neurological complications in coronavirus disease-2019 (COVID-19) via a systematic review of the literature.Methods: We screened all articles resulting from a search of PubMed, Cochrane, Google Scholar and Scopus, using the keywords "COVID-19 and CNS", "SARS-CoV-2 and CNS”, “COVID-19 and neurological manifestation”, “SARS2 and neurological manifestation” and “COVID-19 and Brain” looking for reports of significant neurological manifestations that would potentially have an impact on the outcome.Results: Twenty-six articles met the inclusion criteria. The significant neurological diagnoses reported were stroke, Guillain Barre Syndrome (GBS) and its variants, encephalitis, seizures, acute hemorrhagic necrotizing encephalopathy, acute disseminated encephalomyelitis (ADEM) and transverse myelitis. Although stroke, predominantly ischemic, was observed in ~ 6% of COVID-19 patients from Wuhan, China, mortality in this cohort was 38%. Of the 24 pooled patients with reports of etiology, 17 had large vessel occlusions. GBS occurred in 5/1200 (0.4%) of the COVID-19 cohort from Italy. One of the six reported encephalitis cases, the ADEM case and the report of transverse myelitis do not have data for conclusive diagnosis.Conclusion: The most frequent significant neurological association with COVID-19 is stroke, predominantly ischemic. In a cohort from Wuhan, China, this was as frequent as ~ 6%, with a 38% mortality. Most common reported etiology is large vessel occlusion. Other reported significant neurological complications are GBS/variants, encephalitis, seizures and acute hemorrhagic necrotizing encephalopathy. The reports of ADEM and transverse myelitis lacked diagnostically conclusive data.