Which method uses 10-40% KOH to demonstrate fungal hyphae and spores in clinical material?

Which method uses 10-40% KOH to demonstrate fungal hyphae and spores in clinical material?

• A. Potassium Hydroxide Mount
• B. Wood's lamp
• C. Gram Stain
• D. Calcofluor White Staining

Answer: (A)

Potassium hydroxide mounts use 10–40% KOH to clear keratin and other debris in clinical material such as skin, hair, or nails. The host tissue dissolves, while fungal elements—hyphae and spores—resist digestion, so they become visible under bright-field microscopy as branching, septate filaments or budding yeasts. This method is quick, inexpensive, and can be done at the point of care, making it a practical first-line test for dermatophyte and other fungal infections. Wood’s lamp relies on UV-induced fluorescence and is useful for suggesting certain infections (like Microsporum), but it doesn’t routinely reveal fungal hyphae in a prepared specimen. Gram staining can show fungal elements in some cases but is not specialized for fungi and often provides limited detail for hyphae. Calcofluor white staining highlights fungal cell walls under fluorescence microscopy, increasing sensitivity, but it requires fluorescence equipment.

Potassium hydroxide mounts use 10–40% KOH to clear keratin and other debris in clinical material such as skin, hair, or nails. The host tissue dissolves, while fungal elements—hyphae and spores—resist digestion, so they become visible under bright-field microscopy as branching, septate filaments or budding yeasts. This method is quick, inexpensive, and can be done at the point of care, making it a practical first-line test for dermatophyte and other fungal infections.

Wood’s lamp relies on UV-induced fluorescence and is useful for suggesting certain infections (like Microsporum), but it doesn’t routinely reveal fungal hyphae in a prepared specimen. Gram staining can show fungal elements in some cases but is not specialized for fungi and often provides limited detail for hyphae. Calcofluor white staining highlights fungal cell walls under fluorescence microscopy, increasing sensitivity, but it requires fluorescence equipment.