Mumps, Cervical Zoster, and Facial Paralysis: Coincidence or Association?

The association of mumps with peripheral facial paralysis has been suggested, but its pathogenesis remains unclear. An 8-year-old girl simultaneously developed left peripheral facial paralysis, ipsilateral cervical herpes zoster, and bilateral mumps sialadenitis. Elevated anti-mumps and anti-varicella zoster virus IgM antibodies in serological testing indicated recent infection of mumps and reactivation of VZV. Molecular studies have provided mounting evidence that the mumps virus dysregulates the host’s immune system and enables the virus to proliferate in the infected host cells. This dysregulation of the immune system by mumps virus may have occurred in our patient, enabling the latent VZV infection to reactivate. 1. Introduction A variety of virus infections have been linked to the development of peripheral facial paralysis. These viruses include herpes simplex virus-1 (HSV-1), varicella zoster virus (VZV), Epstein-Barr virus, cytomegalovirus, and mumps virus. Increasing evidence suggests that idiopathic peripheral facial paralysis (Bell’s palsy), the most common clinical entity of facial paralysis, is caused by reactivation of HSV-1 [1, 2]. Similarly, it is well recognized that VZV reactivation is responsible for the development of Ramsay Hunt syndrome and zoster sine herpete [3]. However, the association of other viral infections with the pathogenesis of facial paralysis remains largely unclear because of the paucity of reports. We present here a patient who showed the simultaneous development of left peripheral facial paralysis, ipsilateral cervical herpes zoster, and mumps sialadenitis as evidenced by serological studies. Our case, as well as those in previous reports, raises the question whether the so-called mumps-associated facial paralysis is simply caused by mumps virus infection or the additional reactivation of latent VZV. 2. Case Presentation An 8-year-old Japanese girl was referred to our clinic for the evaluation of a left facial nerve paralysis, left cervical zoster, and swelling of the right submandibular area. She developed cervical zoster and facial paralysis on the first and second day of illness, respectively, and was given prednisolone (1？mg/kg/day) and valaciclovir (1500？mg/day) orally by a pediatrician from the fourth day of illness. She subsequently developed a right submandibular swelling on the eighth day. She did not notice hearing loss or vertigo. She had been vaccinated against mumps at the age of 2 and had no obvious episode of mumps infection previously. Although she had also been vaccinated for chickenpox at the age