Cogan's Syndrome: Complex Diagnostics, Treatment, and Results of Hearing Rehabilitation in Long-Term Follow-Up-Case Series.

Purpose: This study aims to present the diagnostic and therapeutic challenges of Cogan's syndrome (CS) and the outcomes of hearing rehabilitation in long-term follow-up. Methods: Retrospective data analyses of patients with CS treated at Semmelweis University were performed. Comprehensive evaluations, including medical assessments, audiological measurements, otoneurological investigations, imaging, and ophthalmological examinations, were conducted on all patients. Results: Between 1995 and 2022, five patients with CS were followed. The severity and timing of ear and ocular symptoms varied. Bilateral, asymmetric hearing impairment manifested as sudden sensorineural hearing loss, and all patients experienced loss of bilateral vestibular function. Various ophthalmological manifestations showed instability over time. Systemic corticosteroids were the first-line treatment, immunosuppressive therapy (methotrexate, cyclophosphamide, cyclosporin A), and biological treatment (infliximab, adalimumab) used as second- and third-line therapies. Eye symptoms of all five patients were controlled by medications. For hearing impairment, four patients were treated with cochlear implantation and achieved long-term stable speech perception. Hearing improvement was found in one patient by conservative therapy. One patient required reimplantation due to device failure, which was performed without complications. Conclusion: Sudden hearing loss and vestibular attacks in young patients require thorough investigation and close follow-up. Early corticosteroid therapy or immunosuppressive and biological treatment can stabilize symptoms, including hearing levels. Early hearing rehabilitation with cochlear implants is crucial. Long-term follow-up indicates stable hearing levels and speech perception.