Bilateral Facial Weakness with Distal Paresthesia Following COVID-19 Vaccination: A Scoping Review for an Atypical Variant of Guillain-Barré Syndrome.

Recent population-based studies from the US and UK have identified an increase in the occurrence of Guillain-Barré syndrome (GBS) following coronavirus disease 2019 (COVID-19) vaccination. However, the localized variant of GBS might be underestimated due to its rarity and atypical features. We aimed to identify and characterize bilateral facial weakness with distal paresthesia (BFWdp) as a GBS variant following COVID-19 vaccination. Relevant studies published during the COVID-19 pandemic were searched and identified in the MEDLINE, Embase, and other databases. This review found that 18 BFWdp cases presented characteristics similar to previous BFWdp cases as defined in the literature: male dominance, frequent albuminocytological dissociation, and acute inflammatory demyelinating neuropathy pattern. In contrast, facial nerve enhancement on brain MRI and antiganglioside antibody positivity were often observed in BFWdp following COVID-19 vaccination. The mechanism of BFWdp following COVID-19 vaccination appears to be somewhat different from that of sporadic BFWdp. Neurological syndromes with rare incidence and difficulty in diagnosis should be considered adverse events of COVID-19 vaccination.