A very characteristic pattern of inflammation is the active border of infection.

Dermatophytes appear as translucent, branching, rod-shaped filaments (hyphae) of uniform width, with lines of separation (septa) spanning the width and appearing at irregular intervals.

Hyphae may be difficult to find in a potassium hydroxide wet mount. Parker’s blue ink and other stains easily stain the hyphae, rendering them visible under low power.