Cogan syndrome

Rare autoimmune disorder characterized by inflammation of the cornea (non-syphilitic interstitial keratitis) and inner ear (hearing loss, tinnitus, vertigo).

• Can lead to permanent deafness or vision loss if untreated. It's an important vasculitic syndrome in young adults and often tested for its unique combination of eye + ear symptoms requiring prompt immunosuppressive therapy.

• Typical form: Young adult with interstitial keratitis (painful red eye, corneal opacities) plus sudden audiovestibular symptoms (tinnitus, vertigo, sensorineural hearing loss) appearing within ~2 years of each other.
• Atypical form: Variations in ocular inflammation (uveitis, scleritis, conjunctivitis instead of keratitis) or a longer gap (>2 years) between eye and ear symptoms.
• Systemic features in many patients: fever, fatigue, arthritis or arthralgias, and signs of vasculitis (e.g., aortitis causing aortic regurgitation or aneurysm) can occur in ~15%.

1. Always exclude syphilis: obtain serologic tests (VDRL/RPR) – Cogan's is a diagnosis of exclusion (syphilitic interstitial keratitis can mimic it).
2. Refer to ophthalmology for slit-lamp exam to confirm interstitial keratitis or other ocular findings; and to audiology for an audiogram (shows bilateral sensorineural hearing loss).
3. Labs are nonspecific: may see ↑ESR/CRP, anemia or leukocytosis during flares; no specific biomarker (occasionally ANCA or other autoimmune antibodies appear but are not diagnostic).
4. If systemic signs (e.g., unequal blood pressures, new heart murmur), do imaging (CT/MRI) of the aorta to check for vasculitis (aortitis).
5. Multidisciplinary approach: involve ENT (otolaryngology), rheumatology, and ophthalmology; consider tissue biopsy only if needed to rule out other vasculitides (e.g., temporal artery biopsy if giant cell arteritis is a concern).

1. High-dose corticosteroids (systemic prednisone ~1 mg/kg) are first-line to induce remission and protect hearing; also use topical steroid eye drops and cycloplegics for interstitial keratitis.
2. If inadequate response or severe disease, add immunosuppressants (e.g., methotrexate, cyclophosphamide, cyclosporine; or TNF inhibitors like infliximab for refractory cases).
3. Long-term: coordinated care with rheumatology, ENT, and ophthalmology. Monitor for relapse; treat hearing loss supportively (hearing aids or cochlear implants if needed). Screen periodically for vascular complications (e.g., aortic imaging).

• Cogan = Cornea + Cochlea: helps recall the classic eye (corneal keratitis) and ear (cochlear/vestibular) involvement.
• On exams, non-syphilitic interstitial keratitis + hearing loss in a young adult → Cogan's (always check syphilis test).

• Rapidly progressive hearing loss or severe vestibular symptoms → start high-dose steroids immediately to prevent irreversible sensorineural deafness.
• Signs of aortitis (e.g., chest pain, new aortic regurgitation murmur, unequal pulses) → urgent imaging and immunosuppressive therapy (risk of aneurysm or dissection).
• Severe ocular involvement (dense corneal opacification, uveitis) → urgent ophthalmologic treatment to prevent vision loss.

1. Young patient with eye + ear complaints → suspect Cogan syndrome (after basic evaluation).
2. Test for syphilis: if positive, treat syphilis (not Cogan's); if negative, proceed with Cogan workup.
3. Ophtho & ENT eval: perform slit-lamp exam (confirm keratitis) and audiogram (assess hearing loss).
4. Begin corticosteroids promptly (don't wait for biopsy – treat to preserve hearing).
5. If no improvement or systemic vasculitis present → escalate therapy (add DMARDs/biologics); provide supportive care (e.g., vestibular rehab, hearing aids) and specialist follow-up.

• Young adult with episodic vertigo, tinnitus, and a red painful eye with corneal stromal opacities; syphilis tests negative → Cogan syndrome.
• Patient with known Cogan's who develops chest pain and a new diastolic murmur → suspect aortitis (Cogan complication requiring urgent evaluation).
• Exam questions often highlight the need for high-dose steroids in a patient with rapid hearing loss and eye inflammation to prevent permanent deficits.