Vestibular neuronitis. Pathogenesis in the view of virological study of CSF.

Cerebrospinal fluid (CSF) samples from 15 patients with vestibular neuronitis were virologically examined and analyzed, and compared to those from 16 patients with Hunt's syndrome. The results were as follows: The CSF protein in vestibular neuronitis showed an increase, beginning about two weeks after the onset of vertigo, while the cell count remained normal. The CSF protein in Hunt's syndrome rose, but its progress was different from that in vestibular neuronitis. In both diseases, the increase in CSF protein seemed to be due to protein originating in the blood; the increase was probably caused by a disorder of the blood-CSF barrier. There was no direct evidence of an increase in IgG nor viral antibody titers in the CSF in vestibular neuronitis. In cases of Hunt's syndrome with CSF pleocytosis, intrathecal IgG synthesis was detected. It might be possible that HSV or EBV infection can be confirmed serologically in some cases of vestibular neuronitis and that, in those cases, pathogenesis of vestibular neuronitis is similar to that of Hunt's syndrome.