The histology of prolonged candidal infection of the rat's tongue.

Long-term candidal infection of the rat's tongue has been found to produce marked epithelial hyperplasia with keratin trapped between the folds of hyperplastic epithelium. The epithelium showed atypia which did not amount to carcinoma in situ. Degenerative changes were found in the superficial layers of the lingual muscle beneath areas of candidal infection, and after a year, hyalinized fibrous tissue appeared to replace the damaged muscle.