Background and Aims:

Single cases and series of Guillain-Barré syndrome (GBS) were reported during the SARS-CoV-2 outbreak worldwide. We aimed to evaluate the incidence and clinical features of GBS in a cohort of patients from two regions of northern Italy with the highest number of COVID-19 patients.

Methods:

GBS cases diagnosed in 12 referral hospitals in March and April 2020 were retrospectively collected. As a control population, GBS patients diagnosed in March and April 2019 in the same hospitals were considered.

Results:

Incidence of GBS in March and April 2020 was 0.202/100,000 per month (estimated rate 2.43/100.000 per year; C.I. 0.140-0.282) versus 0.077/100.000 per month (estimated rate 0.93/100.000 per year; C.I.: 0.041-0.132) in March and April 2019 with a 2.6-fold increase. Estimated incidence of GBS in COVID-19 positive patients was 47.9/100,000 and in the COVID-19 positive hospitalized patients was 236/100,000.

COVID-positive GBS were compared with COVID-negative patients and a higher frequency of demyelinating subtype (AIDP) (76.6% vs 35.3%; p. 0.005), a lower MRC sum score (26.33 +/- 18.31 vs 41.41 +/- 14.85; p 0.006) and more frequent admission to ICU (66.6% vs 17.6%; p 0.002) were observed.

Conclusions:

This study shows an increased incidence of GBS during the first COVID-19 wave in northern Italy. This might not be unexpected considering that GBS is unanimously considered a post-infectious disease with several new infectious agents even recently added as possible trigger for GBS, including Zika and Hepatitis E viruses. We suggested that a correlation might exist between the COVID-19 and the increase in GBS incidence.