In our study, elevated anti-HEV-IgM and anti-HEV-IgG serum levels were significantly more common in neuralgic amyotrophy/plexus neuritis/radiculitis than in AIDP/CIDP, meningitis/encephalitis, idiopathic peripheral facial paralysis and tension headache. This evidence concerns the gene CD40LG and neuralgic amyotrophy.