Role of viral and Mycoplasma pneumoniae infection in idiopathic sudden sensorineural hearing loss.

Sudden deafness constitutes a challenge in terms of the etiopathogenic diagnosis. The causative origin of sudden deafness usually remains unknown. However, available evidence suggests that viral and Mycoplasma pneumoniae infection could be one factor involved. In order to analyze the incidence of these infectious agents, a microbiology study was carried out during the acute phase of the disease, and during convalescence, in 24 patients (17 men and 7 women; mean age 39.7 years; range 17-63 years) with idiopathic sudden hearing loss (SHL) according to previously published criteria. In the acute phase most of the patients presented IgG antibodies to Epstein-Barr virus (n = 23), herpes simplex virus (n = 24), parainfluenza virus (n = 24), varicella-zoster virus (n = 24) and cytomegalovirus (n = 20). Results obtained from 3 patients suggested the existence of a recent infectious process caused by Mycoplasma pneumoniae (IgM+) in 1 patient, Mycoplasma (IgM+) and influenza A virus (complement fixation titer > 1/64) in another and parainfluenza virus seroconversion (a fourfold higher titer between the acute phase and convalescence) in the third. In conclusion, the low incidence of documented positive serological tests in our series (12.5%) may be due to the presence of pathological situations other than acute infection and does not justify routine serological studies in patients with SHL.