Ocular mycosis

Abstract

Fungal keratitis is one of the most challenging types of microbial keratitis for the ophthalmologist to diagnose and treat. Fungi causing human keratitis take the form of either yeasts or mold. Candida, the major pathogenic yeasts, can be detected in the normal ocular surface flora. Preceding ocular surface disorder, the wearing of contact lenses and the use of antibiotic/steroid eye drops may lead to candida keratitis. Infectious focus caused by Candida tends to melt the corneal stroma. Keratitis caused by mold often develops after an injury caused by soil and/or a plant. Mold can reach the anterior chamber without destroying the stromal layer of the cornea, which results in distinctive clinical features such as endothelial plaque and hyphate ulcer. Fungal keratitis needs to be managed by antifungal agents, most of which must be prepared by ourselves to apply to the ocular surface. Candida keratitis should be managed with azoles. If the infection seems to be caused by mold, several antifungal drugs including pimaricin, which is the only agent officially applicable to the eye, should be used. Some cases of mold keratitis need to have therapeutic penetrating keratoplasty because of their lack of response to intensive medication. Mold causing keratitis is variegated. Fusarium and Aspergillus can reach the intraocular space rapidly. Alternaria and some other unclassified molds remain in the superficial layer of the cornea for a long time. Our experiments indicate that the progress of focus in the cornea is regulated by the receptiveness of mold against temperature.