Hearing loss caused by mumps--epidemiological investigation and clinical features

Abstract

According to the diagnostic criteria of mumps deafness presented by the research team on acute profound sensory neural hearing loss sponsored by the Ministry of Welfare, Japan, we investigated two subjects on mumps deafness; 1) the incidence of the mumps deafness in 1982, in which there was a big epidemic of mumps in Ehime Prefecture, Japan, and 2) clinical features of the mumps deafness based on the analysis of the 40 patients with sudden hearing loss associated with mumps. The incidence of the deafness caused by mumps viral infection was found to be 1 per 18000 patients with mumps (0.0056%). Among the 40 patients whom we experienced for the past seven years, 12 were confirmed and 28 were suspicious to be suffered from mumps deafness according to the diagnostic criteria.Unilateral total hearing loss of sudden onset was characteristic. The complication occurred within 25 days at the latest after the initial swelling of the parotid gland. Although hearing loss and tinnitus were irreversible, decreased caloric response normalized in a year.