Pathology of congenital syphilitic labyrinthitis.

An alarming increase in the incidence of syphilitic labyrinthitis has prompted us to review the pathology of this condition. The temporal bones of two patients with congenital syphilis of the ear were studied histopathologically. They showed diffuse osteitic changes in the otic capsule associated with severe hydrops and degeneration of the membranous labyrinth. The posterosuperior wall of the external auditory canal as well as the auditory ossicles showed numerous connective tissue filled spaces surrounded by thin bony trabeculae. These lesions probably represent healed luetic osteitis. There was severe degeneration of the sensorineural structures in the cochlea. A finding of particular interest was the infiltration and fibrous obliteration of the ductus endolymphaticus in both cases. The significance of these findings in relation to the pathophysiology and treatment of syphilitic labyrinthitis is emphasized.