ULTRASTRUCTURAL FINDINGS IN THE VESTIBULAR END-ORGANS OF AIDS CASES

Neurotologic manifestations are apparent in human immunodeficiency vir us (HIV) infection, but are poorly understood. Symptoms related to the vestibular system include episodes of vertigo, imbalance, ataxia, and nausea. Although patients present more often with hearing impairment, vestibular complaints are described and electrophysiologic studies in dicate vestibular dysfunction in HIV-infected patients. Whether the di sease involvement includes the central, or the peripheral nervous syst em has not been established. Ultrastructural analysis of vestibular en d-organs obtained from HIV autopsy cases revealed pathologic changes i n the labyrinth wall, the epithelial lining, and the receptor maculae and cristae. Cytologic changes in hair cells included inclusion bodies , viral-like particles, and hair bundle malformations. Epithelial lini ng cells, supporting cells, and connective tissue cells had inclusions and viral-like particles. These findings are consistent with those of a previous cochlear study demonstrating intracellular viral-like part icles with the morphologic characteristics of HIV. Further cytologic e valuation of decalcified temporal bones and immunohistochemical analys is of freshly harvested HIV-infected temporal bones may provide furthe r insight into the pathogenesis of viral-induced hearing loss and vest ibular impairment.