Neurosyphilis presenting as visually asymptomatic bilateral optic perineuritis

Area of Science:

• Neurology
• Ophthalmology
• Infectious Diseases

Background:

• Neurosyphilis is a complex infection affecting the central nervous system.
• Ocular manifestations of syphilis can be diverse and may present atypically.

Observation:

• A 39-year-old man presented with headaches and retro-orbital pain, exhibiting bilateral optic nerve swelling on funduscopy.
• Initial neurological and ophthalmological examinations, including visual acuity, visual fields, and pupillary light reflexes, were normal.
• Cranial imaging (CT venogram, MRI) and cerebrospinal fluid (CSF) opening pressure were unremarkable.

Findings:

• CSF analysis revealed positive antibodies for *Treponema pallidum* and a positive *T. pallidum* particle agglutination test, confirming neurosyphilis.
• The patient tested negative for HIV.
• Intravenous benzylpenicillin treatment led to rapid symptom resolution within two weeks.

Implications:

• This case highlights the importance of considering neurosyphilis in patients with unexplained optic nerve swelling, even with normal vision.
• Early diagnosis and treatment of neurosyphilis are crucial for preventing irreversible neurological and visual deficits.
• The atypical presentation underscores the need for comprehensive diagnostic workups in suspected cases of central nervous system infections.