Elevated Serum Interferon Levels in Patients With Bell's Palsy

• Serum interferon (IFN) levels were analyzed in patients with Bell's palsy to study the immune response in the disease. Serum samples from 91 patients were assayed for antiviral activity using a bioassay. The IFN levels in the serum were elevated in the acute and convalescent phases as compared with control subjects. The serum IFN-γ levels were analyzed by radioimmunoassay in 32 of the patients: the IFN-γ levels were alike in the acute and convalescent phases and the control subjects. Neutralization with specific antisera against IFN-α, -β, and -γ on 15 serum samples of 11 patients with elevated IFN activity showed a complex pattern that indicates that the antiviral activity was due to a mixture of IFNs and possibly also due to other factors. The elevated IFN levels indicate a low-grade antiviral response that may reflect the reactivation of a viral infection. ( Arch Otolaryngol Head Neck Surg 1989;115:37-40)