Interstitial keratitis and sensorineural hearing loss as a manifestation of rheumatoid arthritis: clinical lessons from a rare complication.

Cogan's syndrome or non-syphilitic interstitial keratitis with vestibule-auditory dysfunction is a serious and under-recognised complication of rheumatoid arthritis. It is an autoimmune condition characterised by inflammatory infiltrates on the cornea and extensive vestibulocochlear damage. If left untreated, patients progress to develop profound hearing loss. We present a case that was incorrectly diagnosed and treated as conjunctivitis by several emergency departments prior to being correctly recognised as Cogan's syndrome.