Use of mammalian inner ear antigens for the diagnosis of autoimmune sudden loss of vestibular function

It has been postulated that bilateral sensorineural hearing loss (SNHL) may be the result of an ongoing autoimmune process against the inner ear and a pattern of progressive bilateral SNHL linked to an autoimmune inner ear disorder has been reported. Various attempts have been made to develop an assay to confirm the diagnosis of autoimmune inner ear disease. In this study we used a Western blot assay to determine the presence of IgG antibodies directed against a PO antigen (30 kDa) of the guinea pig in the sera of patients affected by sudden loss of vestibular function (SLVF). Ten patients affected by vestibular neuritis were enrolled: eight with unilateral vestibular loss and two with sequential bilateral impairment. We also tested nine patients with sudden unilateral hearing loss, five with benign paroxysmal positional vertigo and six normal subjects. In the present study only one patient, a woman affected by bilateral vestibular impairment, had IgG antibodies against the PO protein. Our results indicat...