Bilateral reversible corneal edema associated with amantadine use

In this article, we report a case of bilateral severe reversible corneal edema caused by amantadine therapy.

A 39-year-old women was referred to us for evaluation of bilateral corneal edema. Her past medical history was significant for multiple sclerosis, anorexia, and seizures. She developed painless progressive bilateral loss of vision for the past 6 months. She was evaluated by several ophthalmologists elsewhere who felt that the patient's visual loss was secondary to a nutritional deficiency as opposed to related to multiple sclerosis. She was started on vitamin B-12 medication without improvement in her symptoms. She was then evaluated by neuro-ophthalmology. The examination revealed severe bilateral corneal edema and was referred to our corneal service for further evaluation of her corneal condition. Our examination revealed best corrected visual acuity of 20/400 bilaterally. Corneal thickness was 940 microm in the right eye and 802 microm in the left. Color vision was intact. Conjunctivas were white bilaterally. Cornea evaluation revealed diffuse stromal edema and Descemet's folds and microcystic subepithelial edema with to guttae noted. Anterior chambers were deep and quiet. A specular microscopy revealed significant pleomorphism and polymegathism with an endothelial cell count of 1,504 cells in the right eye and 1,596 in the left eye.

Review of the patient's medical information revealed therapy with amantadine 2 months prior to the appearance of the patient's symptoms as a means to control the patient's tremors. The patient experienced rapid resolution of the corneal edema within the next 2 months after discontinuation of the agent with recovery of best corrected visual acuity of 20/40 in the right eye and 20/30 in the left.

In cases of unexplained corneal edema and in the absence of any identifiable ocular cause, a review of toxic effects of systemic medications should be performed. Early diagnosis may prevent irreversible endothelial damage. Amantadine can cause endothelial failure and needs to be considered as part of the differential diagnosis of corneal edema.