Otosyphilis a Case Report

    


    


    Figure 2: MRI / this figure shows a thickening of the right and left cochleovestibular nerves.

    

Discussion

Otosyphilis is a rare manifestation of systemic Treponema pallidum bacterial infection, with the most common clinical symptoms including sensorineural hearing loss, tinnitus, and vertigo [4]. Bilateral hearingloss typically occurs acutely with rapid progression, accompanied by vestibulocochlear symptoms [5]. The presentation can also vary between individuals, spanning unilateral and bilateral involvement, asymmetric hearing loss, rapidly progressive to fluctuating hearing loss, spontaneous or provoked disequilibrium, and generalized unsteadiness [6,7]. Audiometric studies often involve the low- and high-frequency ranges [5,8] while sparing middle frequencies [9]. Otosyphilis and neurosyphilis can be diagnosed in all phases of syphilitic infections [4,10]. Treponema pallidum spirochetes can infect the central nervous system, causing hearing loss by syphilitic inflammation of the perilymphatic space, degeneration of the inner ear structures and temporal bone, and impairment of the eighth cranial nerve [4,9,11-14]. Thus, all patients with a confirmed diagnosis of disseminated syphilis should undergo a thorough ocular, otologic, and neurologic examination [13].

The diagnosis of otosyphilis is inherently challenging as it requires a high index of clinical suspicion even in the context of confirmatory serology. There does not exist a practical way to perform a treponemal test on the perilymphatic fluid nor a histologic examination of the temporal bone [4,12,16]. Diagnosis is multistep, typically requiring a combination of compatible neurologic, cochlear, and vestibular symptoms, a positive serologic test, CSF abnormalities, and/or audiologic studies [4,6,13]. Otosyphilis is also a diagnosis of exclusion, requiring that hearing loss is not caused by another discernable organic inner ear pathology [4,6,11,15].

Cette patiente a présenté une atteinte subaiguë des nerfs cochlé-ovestibulaire avec à IRM un épaississement et une prise de contraste pathologique de celui-ci correspondant probablement à une infiltration nerveuse inflammatoire lymphocytaire péri-vasculaire. De telles anomalies IRM sont aspécifiques et peuvent se rencontrer dans des pathologies très diverses (Table 1) comme une méningite carcinomateuse, une localisation méningée de lymphome, une neuro-sarcoïdose, une granulomatose de Wegener, une tuberculose neuromeningé, une neurosyphilis, une neuro- borreliose ou dans certaines infections virales (Smith et Anderson, 2000 ; Corr, Bhigjee & Lockhat, 2004).

  


    
Tumoral causes: 

  

  


    
- Carcinomatous meningitis 

  

  


    
- Meningeal involvement in    lymphomas 

  

  


    
- Neurofibromatosis type 2 

  

  


    
Autoimmune causes: 

  

  


    
- Sarcoidosis 

  

  


    
- Wegener's disease and other    granulomatoses 

  

  


    
- Connective tissue diseases 

  

  


    
Infectious causes: 

  

  


    
- Viral 

  

  


    
- Tuberculosis 

  

  


    
- Syphilis 

  

  


    
- Lyme disease 

  

  


    
Traumatic causes 

  

Table 1: Multiple cranial involvements with MRI abnormalities (cranial nerves thickening and gadolinium enhancement).