What is the Difference Between Microsporum Trichophyton and Epidermophyton

The main difference between Microsporum Trichophyton and Epidermophyton is that Microsporum is a zoophilic dermatophyte, and Trichophyton is both zoophilic and anthropophilic, whereas Epidermophyton is an anthropophilic dermatophyte.

Microsporum, Trichophyton, and Epidermophyton are three types of dermatophytes that belong to the division Ascomycota. They use keratinase enzymes to digest keratin as a nutrient source.

Key Areas Covered

1. What is Microsporum
     – Definition, Structure, Importance
2. What is Trichophyton
     – Definition, Structure, Importance
3. What is Epidermophyton
     – Definition, Structure, Importance
3. Similarities Between Microsporum Trichophyton and Epidermophyton
     – Outline of Common Features
4. Difference Between Microsporum Trichophyton and Epidermophyton
     – Comparison of Key Differences

Key Terms

Epidermophyton, Microsporum, Trichophyton

What is Microsporum

Microsporum is a fungus that causes fungal infections in the skin called tinea capitis, tinea corporis, ringworm, etc. On the other hand, Microsporum contains both macroconidia and microconidia. Macroconidia are large asexual reproductive structures, while microconidia are small asexual reproductive structures. They occur on short conidiophores.

Figure 1: Microsporum Canis

Macroconidia are hyaline and multi-septate. They are also spindle shape or obovate. The size of the macroconidia is 7–20 by 30–160 um. The cell walls of the macroconidia are thin or thick and echinulate to verrucose. In comparison, microconidia are hyaline, single-celled, smooth-walled, and 2.5–3.5 by 4–7 um in size.

What is Trichophyton

Trichophyton is a fungus that causes tinea, including athlete’s foot, ringworm, jock itch, and similar infections of the nail, beard, skin, and scalp. It also develops smooth-walled macro- and microconidia. Macroconidia occurs directly on the hyphae or on short pedicels. They contain thin to thick cell walls that are clavate to fusiform and 4 to 8 by 8 to 50 μm in size. Macroconidia are absent or few in most species of Trichophyton.

Figure 2: Trichophyton Rubrum var. Rodhaini

Microconidia are spherical, pyriform to clavate, or irregular in shape. In addition, they are 2 to 4 μm in size.

What is Epidermophyton

Epidermophton is another genus of fungi that cause fungal infections. It also causes superficial and cutaneous mycoses, including E. floccosum, and causes tinea unguium (fungal infection of the nail bed), tinea corporis (ringworm), tinea cruris (jock itch), and tinea pedis (athlete’s foot). Epidermophyton contains smooth, thin-walled, club-shaped macroconidia and does not contain microconidia.

Figure 3: Epidermophyton Floccosum

Apart from that, Epidermophyton is an anthropophilic dermatophyte that prefers infecting humans. In comparison, zoophilic dermatophytes prefer infecting animals rather than humans.  

Similarities Between Microsporum Trichophyton and Epidermophyton

• Microsporum, Trichophyton, and Epidermophyton are three types of fungi genera that are dermatophytes.
• They belong to the division Ascomycota.
• They are keratinophilic fungi that digest keratin with the use of keratinase enzyme as the source of nutrients.
• Infections of these fungi occur in the superficial keratinized structures such as hair, nails, and the stratum corneum of the skin.
• Different forms of infections include tinea capitis (scalp ringworm), tinea corporis (ringworm), tinea cruris (jock itch), tinea pedis (athlete’s foot), and tinea unguium (onychomycosis).
• These fungi are uniformly resistant to cycloheximide.

Difference Between Microsporum Trichophyton and Epidermophyton

Definition

Microsporum refers to a genus of fungi that causes tinea capitis, tinea corporis, ringworm, and other dermatophytoses (fungal infections of the skin), and Trichophyton refers to a genus of fungi of the family Moniliaceae that are parasitic in the skin and hair follicles, while Epidermophyton refers to a genus of fungus causing superficial and cutaneous mycoses, including E. floccosum.

Environment

Microsporum is a zoophilic dermatophyte, Trichophyton is both zoophilic and anthropophilic while Epidermophyton is an anthropophilic dermatophyte.

Macroconidia and Microconidia

Furthermore, Microsporum contains both macroconidia and microconidia, and Trichophyton contains only microconidia, while Epidermophyton contains only macroconidia.

Conclusion

In brief, Microsporum, Trichophyton, and Epodermophyton are three genera of dermatophytes that cause fungal infections in the superficial keratinized structures such as hair, nails, and the stratum corneum of the skin. They use keratin as their nutrient source by digesting keratin with the enzyme keratinase. Microsporum is a dermatophyte that is zoophilic. Trichophyton is both zoophilic and anthropophilic. In comparison, Epidermophyton is an anthripophilic dermatophyte. Therefore, the main difference between Microsporum Trichophyton and Epidermophyton is their environment.

References:

1. Centers for Disease Control and Prevention. (2021, February 26). About ringworm. Centers for Disease Control and Prevention. 

Image Courtesy:

1. “Macroconidia Microsporum canis.” By Roberto J. Galindo – Own work (CC-BY SA 3.0) via Commons Wikimedia
2. “Trichophyton rubrum var rodhaini” By CDC – Own Work (Public Domain) via Commons Wikimedia
3. “Epidermophyton floccosum 01” By CDC – Own Work (Public Domain) via Commons Wikimedia