Unilateral Mooren's ulcer in a patient with bilateral partial optic nerve atrophy - a case report.

Objective: The aim of this report is to present the diagnostic and therapeutic approach in a case of long standing peripheral ulcerative keratitis of a patient with already decreased visual acuity due to preexistent optic nerve partial atrophy. Case presentation: A 58-year-old male patient presented to our clinic with unilateral pain, photophobia, tearing and decreased visual acuity in the right eye. The symptomatology began 4 months prior to the presentation, after trauma with a vegetative corneal foreign body, for which he received treatment in another Ophthalmology Service. After every specific cause of peripheral ulcerative keratitis was excluded, using extensive laboratory testing, the diagnosis of unilateral Mooren's ulcer in the right eye was established and the topical steroid treatment was initiated. A very good response to the treatment was observed, with complete resolution of the affliction. Discussions: Mooren's ulcer represents an idiopathic form of peripheral ulcerative keratitis. The diagnostic approach in this type of cases consists in the exclusion of infectious etiology (to safely use topical steroids) and of specific autoimmune etiologies. As the evolution of this pathology is severe with frequent complications, the treatment must be initiated as soon as possible. Conclusions: Despite being a rare diagnosis, Mooren's ulcer must be considered in cases in which clinical and paraclinical presentation is highly suggestive. A rapid therapeutic approach can offer good results despite the usual severe evolution of this disease.