Cogan's syndrome manifesting as sudden bilateral deafness: diagnosis and management

Cogan's syndrome is an uncommon entity of nonsyphilitic interstitial keratitis with vestibulo-auditory disturbances. Although it is unusual, Cogan's syndrome should be considered in the differential diagnosis of patients with sudden hearing loss, even when they lack ophthalmologic symptoms. Systemic manifestations are not uncommon and, along with serologic and hematologic abnormalities, may help in making the diagnosis, which requires a high index of suspicion. Treatment with steroids has largely been based on symptoms. We suggest using the C-reactive protein level as a monitor of subclinical disease activity; it is therefore beneficial in the adjustment of steroid therapy. We have described the case of a 41-year-old woman who sought treatment for an upper respiratory infection syndrome and severe vertigo. Evaluation included hematologic and serologic studies, lumbar puncture, and CT and MRI scans. Abnormal findings consisted of an elevated white blood cell count and an ESR of 112 mm/hr. Six days later, profound, bilateral sensorineural hearing loss developed suddenly. Intensive corticosteroid and vasodilator therapies were instituted, but there was no improvement in hearing levels. Ten days later eye pain and redness developed, and ophthalmologic evaluation revealed an interstitial keratitis consistent with Cogan's syndrome. Steroid eye drops and oral prednisone therapy promptly relieved the eye symptoms. Steroid tapering was associated with diffuse joint pain and swelling consistent with a systemic vasculitis. After rheumatologic consultation, steroid dosage was titrated to the CRP level and ESR, and vasculitic symptoms resolved. Hearing levels did not improve, and the patient had cochlear implantation. Thirteen cases of bilateral sudden deafness due to Cogan's syndrome have been reported previously. This is the first case in which there were no immediate eye symptoms.