MNT Onychomycosis and Fungal Infections

Question 1

The most common causative organism of onychomycosis is:

Accepted Answer

Trichophyton rubrum

Answer

Trichophyton rubrum is the most prevalent dermatophyte causing onychomycosis worldwide, accounting for approximately 70% of cases.

Question 2

Distal-lateral subungual onychomycosis (DLSO) characteristically begins at the:

Accepted Answer

Distal and lateral nail bed, progressing proximally

Answer

DLSO is the most common clinical pattern, starting at the hyponychium (distal nail bed) and spreading proximally beneath the nail plate.

Question 3

Which clinical sign distinguishes proximal subungual onychomycosis (PSO) from other types?

Accepted Answer

White opacity beginning at the proximal nail plate near the cuticle

Answer

PSO presents with white/opaque discoloration at the proximal nail, near the cuticle, as fungi enter through the proximal nail fold; it is often associated with immunosuppression.

Question 4

Nail debridement in onychomycosis management primarily aims to:

Accepted Answer

Reduce fungal load and improve topical antifungal penetration to the nail bed

Answer

Mechanical debridement removes infected nail material, reducing fungal burden and allowing topical agents to penetrate more deeply to the infection site.

Question 5

KOH (potassium hydroxide) preparation is used in onychomycosis diagnosis to:

Accepted Answer

Dissolve keratin and visualize fungal hyphae microscopically

Answer

KOH dissolves keratin without destroying fungal cell walls, allowing microscopic visualization of hyphae, pseudohyphae, or spores to confirm fungal infection.

(MNT) Certified Medical Nail Technician Practice Test

(MNT) Certified Medical Nail Technician Practice Test

MNT Onychomycosis and Fungal Infections