Antifungals and their use in veterinary ophthalmology

Mycotic infections can be divided into those that result in superficial disease and those that result in systemic disease. Factors determining the ocular tissue predilection and type of disease caused by a particular fungal organism include fungal species characteristics and host predisposition (large ocular surface area [1], prominent eyes [1], local or systemic immunoprotection [2], and geographic location [3]). Additionally, superficial corneal disease may be exacerbated by exposure to vegetative material (hay, grasses, shavings, and straw) and dust [2], whereas concurrent illness or immunocompromise may predispose to systemic disease. Although horses are most commonly affected with ocular surface fungal infections (keratomycosis), dogs and cats are predisposed to internal ocular infections (anterior uveitis, chorioretinitis, retinal detachment, and secondary glaucoma) and systemic disease. The aim of this article is to provide a general outline of the current knowledge of antifungal agents in veterinary ophthalmology. Few agents are approved by the US Food and Drug Administration (FDA) for the treatment of companion animal fungal infections. Therefore, extralabel use of products approved for human beings and compounding of specific agents may be necessary, particularly in the treatment of keratomycoses.