The Case
A 32-year-old Ethiopian woman presented with 6 months of persistent unilateral purulent otorrhea and progressive hearing loss, despite multiple courses of topical antibiotics. Otoscopy demonstrated two central tympanic membrane perforations with active discharge. She had no tinnitus, vertigo, systemic manifestations of syphilis, or neurologic abnormalities.

The Diagnostic Clue
Audiometry showed an unusual finding for otosyphilis: isolated moderate conductive hearing loss, with normal bone conduction and a 35-dB air–bone gap. Temporal-bone CT demonstrated middle-ear soft-tissue opacification without cholesteatoma, ossicular erosion, or labyrinthine disease.

Serum VDRL was reactive at 1:16 and TPHA was positive. HIV testing was negative, and CSF examination, including CSF VDRL, was unremarkable. Tympanic membrane granulation tissue showed plasma-cell-rich granulomatous inflammation, with Warthin-Starry staining demonstrating organisms morphologically consistent with spirochetes. Importantly, the authors acknowledge that this stain is not specific for Treponema pallidum and that PCR and immunohistochemistry were unavailable.

Management and Outcome
Because IV aqueous penicillin G was unavailable, the patient received benzathine penicillin G 2.4 million units IM weekly for 3 weeks, an explicitly nonstandard regimen for otosyphilis, together with a prednisone taper. She subsequently underwent tympanoplasty.

At follow-up:

• Otorrhea completely resolved.
• The air–bone gap improved from 35 dB to 12 dB.
• VDRL declined from 1:16 to 1:2.
• The patient reported substantial subjective hearing improvement.

Clinical Pearl

Syphilis remains the “great imitator”—even in the middle ear. Otosyphilis classically produces sensorineural hearing loss, tinnitus, and vertigo, but syphilitic middle-ear disease can rarely mimic chronic suppurative otitis media with purely conductive hearing loss.

In persistent or treatment-refractory otitis media, particularly when the presentation is atypical, syphilis deserves consideration even without systemic manifestations or cochleovestibular symptoms. A negative CSF evaluation does not by itself exclude otosyphilis or localized syphilitic ear disease.

Take-home: When chronic otorrhea and conductive hearing loss do not behave like ordinary chronic otitis media, broaden the differential. Sometimes the diagnosis is hiding in plain hearing.