Environmental and behavioral factors make horses susceptible to corneal and conjunctival lesions, since these structures are constantly exposed to bacteria and fungi specially Aspergillus spp. and Fusarium spp. Bacterial and fungal ulcerative keratitis, as well as non-ulcerative fungal keratitis such as stromal abscess, are frequent in horses. A "cascade" effect follows the initial lesion which triggers the release of inflammatory cytokines followed by an acute and severe infiltrate of polymorphonuclear cells in the cornea. The cornea becomes susceptible to the activity of proteolytic enzymes released by microorganisms and polymorphonuclear cells, resulting in stromal degradation and ocular perforation. The medical treatment targeting the corneal disease and the controlling of reflexive uveitis should be aggressive and surgical therapy should be associated in most of the cases. This paper reviews the pathophysiology of keratomycosis in horses and specific aspects of the treatment in this species.
ulcerative keratitis; keratomycosis; stromal abscess; fungal; equine
