PURPOSE. A model of experimental keratomycosis was established that mimics
human disease in which the only fungi present are those that are actively g
rowing within the cornea.
METHODS. Dutch-belted rabbits received a subconjunctival injection of triam
cinolone acetonide to one eye. One day later the epithelium was removed fro
m the central cornea and a standardized inoculum of Candida albicans blasto
-conidia was placed on the corneal surface and covered with a contact lens.
The lids were closed with a lateral tarsorraphy. After 24 hours, the lid s
utures and contact lens were removed. Five days later the animals were kill
ed, and their corneas were subjected to separate isolate recovery and histo
logy studies. A group of similarly infected rabbits without corticosteroid
injection served as controls.
RESULTS. Both groups developed invasive corneal disease. Although isolate r
ecovery was not significantly different from corticosteroid-treated rabbits
compared with controls, fungal biomass was increased. Hyphal invasion was
limited to the anterior cornea in control eyes, but penetrated deep stroma
in most of the corticosteroid-treated rabbits.
CONCLUSIONS. Invasive corneal disease can be established with a surface ino
culum. Corticosteroid administration increased corneal penetration of hypha
e. Quantitative isolate recovery is not a reliable measure of the fungal lo
ad within the cornea.