CNS involvement can occur at any stage of syphilis. Among patients with secondary syphilis, around 18% may have neurological signs (including ocular disease) or symptoms . Ocular involvement may be silent or present as anterior uveitis, choroiditis, interstitial keratitis, retinal vasculitis, retinitis, optic neuritis, dacryoadenitis or scleritis. Tamesis and Foster reported that uveitis was the most common ocular manifestation in ocular syphilis . Ocular syphilis has been reported in both immunocompromised and immunocompetent individuals . Due to the wide variety of clinical forms it can take, syphilis has been referred to as ‘the great pretender or simulator’ and should be ruled out in all patients with ocular inflammation. Optic nerve involvement in syphilis may be unilateral or bilateral and becomes apparent as perineuritis, anterior or retrobulbar optic neuritis or papilloedema. In the present case, a unilateral optic disc oedema was detected, which disappeared slowly until its final resolution 3 months after the onset of symptoms. Beyond this optic disc oedema, an area of optic atrophy was observed by OCT. However, the patient's visual field was unaffected, and no changes indicative of recovery were detected. Thus, in the present case, OCT (to quantify optic disc oedema) was more sensitive than perimetry at identifying and monitoring optic neuritis .
Posterior segment and optic nerve involvement can be an important manifestation of ocular syphilis associated to HIV infection , and as in our patient, it often leads to the initial HIV diagnosis . In this case, the HIV infection was coincidental and was investigated due to the diagnosis of syphilis. Moreover, a patient with a first-discovered HIV infection should also be checked for syphilis. A higher incidence of neurosyphilis occurs in syphilis concurrent with HIV, may give rise to ocular complications and may show a more aggressive course [12, 13]. In addition, acquired syphilis, both secondary and tertiary, may cause deafness, which is usually unilateral, although in some patients can be bilateral .
For some time, the treatment of choice for neurosyphilis has been prolonged high-dose intravenous penicillin and has been related to a good prognosis for visual and hearing impairment . The successful use of ceftriaxone has also been described . Oral and intravenous corticosteroids are commonly given as adjuvants for posterior uveitis, scleritis and optic neuritis. Penicillin plus corticosteroid-based regimens have also proved effective at improving hearing, tinnitus and vertigo. The factors associated with a good response include fluctuating symptoms, especially hearing, hearing loss with a duration of less than 5 years and an age under 60 years .
This report describes an infrequent case of unilateral optic neuropathy and ipsilateral involvement of the vestibulocochlear nerve as simultaneously presenting symptoms of syphilis and HIV coinfection.