For a general discussion, and for links to other system-specific manifestations, please refer to the article on syphilis.
The pathological features of syphilitic labyrinthitis consist of:
- severe endolymphatic hydrops
- degeneration of the membranous labyrinth
- diffuse osteitis
Electrocochleography of otosyphilis patients is similar to those of Meniere disease.1
The FTA-Abs assay reliably indicates a history of exposure to Treponema pallidum or cross-reacting antigen, however, does not distinguish between active and treated disease. Whilst FTA-Abs assays have high sensitivity and specificity (100% and 98% respectively) due to the very low levels of disease prevalence the positive predictive value is only 22%.2 Western blot assays are however able to confirm if the infection is active. Clinically, patients report vertigo that lasts minutes to hours, and the Tullio phenomenon may also be present, whereby motion of the tympanic membrane and ossicular chain (loud noise) can induce vertigo and nystagmus (Hennebert sign) in patients with otic syphilis, but may also occur in perilymph fistula and semicircular canal dehiscence.3
Radiographic features are best appreciated on MRI:
- gummas may be seen in the internal auditory canal 4
- there may be radiographic evidence of osteitis and osteolysis of the adjacent temporal bone 4
Furthermore, other manifestations of neurosyphilis may also be evident, in particular, those of acute syphilitic meningitis 4.
- 1. Nagasaki T, Watanabe Y, Aso S, Mizukoshi K. Electrocochleography in syphilitic hearing loss. Acta Otolaryngol Suppl 1993; 504: 68–73
- 2. Hughes GB, Rutherford I. Predictive value of serologic tests for syphilis in otology. Ann Otol Rhinol Laryngol 1986; 95: 250–259
- 3. Minor LB, Carey JP, Cremer PD, et al: Dehiscence of bone overlying the superior canal as a cause of apparent conductive hearing loss. Otol Neurotol 24:270–278, 2003.
- 4. Kivekäs I, Vasama JP, Hakomäki J. Bilateral Temporal Bone Otosyphilis. Otology & Neurotology. 2014 Feb 1;35(2):e90-1.
Related Radiopaedia articles
Inner ear pathology
inner ear anatomy
- enlarged vestibular aqueduct
- semicircular canal dysplasia
- classification of cochlear anomalies
- infection and inflammation
- trauma and miscellaneous