The Association Between Bell's Palsy and Vestibular Dysfunction in Relation to IgG Antibodies to Neurotropic Viruses

Background/Objectives: The aetiology of Bell's palsy remains unclear and is typically diagnosed by exclusion. This study investigated the potential role of neurotropic viruses and explored the relationship between facial nerve impairment and vestibular dysfunction to improve the understanding of the condition. Methods: Antibodies against herpes simplex virus (HSV) and varicella-zoster virus (VZV) were assessed using ELISA. Vestibular function was evaluated through computerised videonystagmography, rotatory chair, and clinical vestibulospinal assessments. Facial nerve lesion localisation was determined by stapedial reflex testing. Fisher's exact test was used for statistical analysis. Results: Of 51 patients with Bell's palsy, 62.7% exhibited vestibular dysfunction, and 70.6% were IgG-positive for at least one neurotropic virus. Vestibular impairment was significantly more common in seropositive patients. Statistically significant associations were observed between vestibular dysfunction and viral IgG seropositivity (p < 0.0001), the severity of vestibular dysfunction and facial paresis (p = 0.0126), and the side of vestibular impairment and the side of facial palsy (p < 0.0001), with 90.6% of cases showing ipsilateral involvement. Conclusions: These findings support the hypothesis that neurotropic viruses may act as a common pathological factor in both Bell's palsy and associated vestibular dysfunction.