Detection of Herpes Simplex and Varicella-Zoster Viruses in Patients with Bell's Palsy by the Polymerase Chain Reaction Technique

Abstract

Infectious causes of peripheral facial paralysis are well known. Bell's palsy, however, is an idiopathic facial paralysis, and the genesis is still unknown. Herpes simplex virus type 1 (HSV-1) and varicella-zoster virus (VZV) have been suggested as etiologic agents. Twenty consecutive adult patients with Bell's palsy were included in the study. Ten adult patients operated on for chronic otitis served as controls. A biopsy specimen from the posterior auricular muscle was resected within 72 hours after the onset of Bell's palsy and was analyzed together with cerebrospinal fluid (CSF) by nested polymerase chain reaction for HSV-1 and VZV DNA. Serum samples were analyzed for antibodies to HSV-1 and VZV. HSV-1 DNA was found in the muscle biopsy specimen from 1 of the 20 patients, but was not found in any of the CSF samples. VZV DNA was detected in the muscle biopsy as well as the CSF from 1 other patient. All controls were negative. Seventeen of 19 patients had stationary serum antibody concentrations to HSV-1, and none displayed an antibody titer rise. A significant antibody titer rise to VZV was found in 1 of 19 patients, whereas 17 of 19 had stationary antibody levels. HSV-1 or VZV DNA was detected in 10% of patients with Bell's palsy in the present study. Viral replication might already have declined in many cases at the onset of the palsy. Use of an HSV-1/VZV polymerase chain reaction on a muscle biopsy specimen or CSF does not seem to be the method of choice for rapid etiologic diagnosis in the acute phase of Bell's palsy.