SARS-CoV-2 and the Guillain-Barré syndrome – features for a complex association

Background. Guillain-Barré syndrome (GBS), the most common cause of flaccid motor deficit with acute or subacute onset, is associated in approximately 2/3 of cases with a history of microbial, predominantly viral, infection. In the context of the current COVID-19 pandemic, the presence of patients with both peripheral nervous system pathology and SARS-CoV-2 viral infection raised questions among researchers whether there may be a possible link between the two entities. Thus, this narrative review aims to provide a clearer perspective on this topic, addressing several issues. Methods. The authors performed independent research of the available literature in the most important electronic databases (PubMed, Google Scholar, and Science Direct). After applying the exclusion criteria, the reviewers focused on the most relevant articles published during the last 18 months, focusing on epidemiological and pathophysiological data regarding GBS and COVID-19. Results. In the first part, a summary of the most important results from the literature on the epidemiological situation in different parts of the world was conducted. Subsequently, possible immunological theories are presented in order to explain the epidemiological association between GBS and COVID-19 infection. Finally, the authors propose new research directions on the topic, discussing the issue of the COVID-19 vaccine, with its short and long term effects, and possible correlations with peripheral nerve pathology. Conclusion. Neurological manifestation in COVID-19 may represent a challenge for the clinician, and with growing numbers of unprecedented cases of peripheral nerve pathology associated with the SARS-CoV-2 virus being reported, further research is urgently needed.