When performing a tease mount, which stain is commonly applied to observe fungal structures?

• A. LCB stain
• B. Gram stain
• C. Ziehl-Neelsen
• D. India ink

Answer: (A)

Tease mounts rely on a stain that makes fungal cell walls stand out so you can clearly see hyphae, septa, and spores. Lactophenol Cotton Blue does exactly that: the phenol clears and fixes the specimen, the lactophenol preserves structures, and the Cotton Blue binds to chitin in the fungal cell walls, giving a strong blue contrast against the background. This combination provides a sharp view of fungal morphology under the microscope, making it the go-to choice for observing fungal structures in a tease mount.

Other stains aren’t ideal for this purpose: Gram stain is not specifically suited for fungi and can give inconsistent results with fungal elements; Ziehl-Neelsen targets acid-fast bacteria and isn’t used for observing fungal morphology; India ink is a negative stain used mainly to visualize capsules around certain yeasts, not to reveal general fungal structures in a tease mount.