Supplementary Material for: Atypical Cogan’s Syndrome Presenting as Anterior Scleritis: Case Report

Purpose: To report a rare case of atypical Cogan’s syndrome presenting with unilateral anterior scleritis and bilateral sensorineural hearing loss, and to outline the therapeutic course. Methods: A case report. Results: A 40-year-old white female presented with recurrent episodes of ocular inflammation and sensorineural hearing loss over a 10-year period, initially treated as isolated conditions. She was evaluated for systemic autoimmune and infectious causes, which were all excluded through serologic and imaging studies. Anterior scleritis was confirmed on ophthalmic examination with incomplete blanching on topical phenylephrine testing. Audiometry revealed bilateral sensorineural hearing loss. A diagnosis of atypical Cogan’s syndrome was made based on clinical history and exclusion of other etiologies. High-dose oral corticosteroids (prednisolone 40 mg daily) led to initial improvement. However, the patient experienced disease flares following intolerance or inadequate response to several steroid-sparing agents, including methotrexate (discontinued due to alopecia after 3 months), azathioprine (150 mg daily for 6 months), and mycophenolate mofetil (3000 mg daily for 6 months). A subconjunctival triamcinolone injection (40 mg) was administered during a relapse, and adalimumab (40 mg subcutaneously every 2 weeks) was subsequently initiated, resulting in clinical stability with no further ocular or auditory deterioration at 12-month follow-up. Conclusion: Cogan's syndrome is a rare autoimmune vasculitis that can present with various ocular and auditory manifestations. While interstitial keratitis is classically described, anterior scleritis represents a less common but recognized presentation. This case underscores the importance of considering atypical Cogan's syndrome in patients with recurrent ocular inflammation and sensorineural hearing loss, particularly when these symptoms occur together or in temporal proximity. Early recognition of the unifying diagnosis and prompt escalation to biologic therapy when conventional immunosuppressants fail may prevent irreversible audiovestibular damage.