Making a distinction between facial palsy due to Lyme neuroborreliosis (LNB) and idiopathic facial palsy (IFP) is of importance to ensure timely and adequate treatment. The study objective was to assess incidence and patient characteristics of facial palsy due to LNB. Hospital records were reviewed of adult patients with facial palsy visiting the departments of neurology and/or otorhinolaryngology of Gelre hospitals between June 2007 and December 2017. Gelre hospitals are located in an area endemic for Lyme borreliosis. Patients with LNB had pleocytosis and intrathecal antibody production or pleocytosis with positive IgG serology. Patients with IFP had negative serology. Clinical characteristics were compared between patients with LNB and patients with IFP. Five hundred and fifty-nine patients presented with facial palsy, 4.7% (26) had LNB and 39.4% (220) IFP. The incidence of facial palsy due to LNB was 0.9/100 000 inhabitants/year. Over 70% of patients with facial palsy due to LNB did not report a recent tick bite and/or erythema migrans (EM). Patients with facial palsy due to LNB presented more often in July to September (69.2% vs. 21.9%, P < 0.001), and had more often headache (42.3% vs. 15.5%, P < 0.01). To reduce the risk of underdiagnosing LNB in an endemic area, we recommend testing for LNB in patients with facial palsy in summer months especially when presenting with headache, irrespective of a recent tick bite and/or EM.
Keywords: Borrelia; Lyme neuroborreliosis; facial palsy; idiopathic facial palsy; tick-borne disease.