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Tinea Corporis Pathology: 4 Histopathological Patterns Explained

Detailed histopathological analysis of tinea corporis, the pathology behind body ringworm fungal infections.

By Medha deb
Created on

Author: Dr. Harriet Cheng, Dermatopathologist, Reviewed: Dr. Amanda Oakley, Dermatologist

Pathogenesis

Tinea corporis represents a dermatophyte infection of the glabrous skin (skin without terminal hairs). The term tinea refers to superficial mycoses (fungal infections) characterised by epidermal invasion by filamentous fungi known as dermatophytes.

These fungi exist as moulds** (filamentous structures) or

yeasts

(unicellular forms). The three main genera of dermatophytes are Trichophyton, Microsporum and Epidermophyton. There are over 40 species capable of causing human disease.

Dermatophytes infect actively keratinised tissue u2014 the stratum corneum, hair and nails. Infection of the horny layer of the epidermis is termed a dermatophytosis or dermatophyte infection.

SiteDisease name
Glabrous (non-hairy) skinTinea corporis
ScalpTinea capitis
Beard areaTinea barbae
FaceTinea faciei
FeetTinea pedis
HandsTinea manuum
NailsOnychomycosis
GroinTinea cruris

How do dermatophytes cause disease?

Dermatophytes produce keratinases (proteases that degrade keratin). These enzymes enable the fungus to penetrate keratinised tissue. The fungi grow in and colonise the keratin debris found between and within the cells of the stratum corneum.

The dermatophyte hyphae grow along the stratum corneum towards the skin surface, forming a mycelium (a branching network of hyphae). This is known as centrifugal** growth.

Arthroconidia

(fungal spores) are formed from the hyphae by segmentation. These spores are shed from the skin surface and are the infectious agents.

"Arthroconidia
Arthroconidia of dermatophyte

Neutrophils are attracted to the site of infection. They release proteolytic enzymes that digest the surrounding epidermis, forming a subcorneal pustule.

Lymphocytes and histiocytes (macrophages) accumulate around the hair follicles and blood vessels in the superficial dermis.

Histology

The histopathological features of tinea corporis depend on the host immune response. There are four main patterns of reaction.

Pattern 1: Suppurative inflammation

The most acute pattern of response is suppurative** inflammation (**neutrophilic**. Collections of neutrophils infiltrate the stratum corneum forming

spongiform pustules

of Kogoj (intraepidermal) and/or

subcorneal pustules

.

"Spongiform
Spongiform pustule of Kogoj

Septate hyphae and arthroconidia may be seen within the stratum corneum.

"Hyphae
Hyphae and arthroconidia in stratum corneum

Pattern 2: Lymphohistiocytic inflammation

The most common pattern is lymphohistiocytic** inflammation (**chronic active). A

lichenoid

(band-like) infiltrate of lymphocytes and histiocytes accumulates at the dermoepidermal junction.

Spongiosis (intercellular oedema) of the epidermis may be present.

"Lichenoid
Lichenoid infiltrate in tinea corporis

Hyphae may be seen within the stratum corneum on higher power magnification (×40). A periodic acid-Schiff (PAS) stain highlights the fungal elements (magenta).

"PAS
PAS stain highlighting hyphae

Pattern 3: Granulomatous inflammation

Granulomatous** inflammation (**chronic) consists of dermal nodules of histiocytes, multinucleated giant cells and lymphocytes.

This pattern may be seen with Majocchi granuloma (perifollicular dermatophyte infection) or when hyphae are difficult to identify.

"Granulomatous
Granulomatous inflammation

Pattern 4: No inflammation

A minority of infections show fungal hyphae within the stratum corneum with no inflammatory response. This pattern may be seen in immunocompromised patients.

Histopathology images

"Low
Low power view showing compact orthokeratosis, parakeratosis and subtle spongiosis. Focal collections of neutrophils within the parakeratosis. PASD shows numerous hyphae within the stratum corneum.
"Higher
Higher power view showing hyphae highlighted by PAS stain
"Spongiform
Spongiform pustule of Kogoj
"Lichenoid
Lichenoid infiltrate with spongiosis

Frequently asked questions

What is the pathogenesis of tinea corporis?

Dermatophytes produce keratinases that enable invasion of the stratum corneum. Hyphae grow centrifugally and arthroconidia are shed as infectious particles.

What are the four histopathological patterns in tinea corporis?

1. Suppurative (neutrophilic) inflammation with spongiform pustules
2. Lymphohistiocytic (lichenoid) inflammation
3. Granulomatous inflammation
4. No inflammation

How is the diagnosis of tinea corporis confirmed histologically?

Septate hyphae and arthroconidia within the stratum corneum, best visualised with PAS or GMS stains. Inflammatory patterns vary based on host response.

What is a spongiform pustule of Kogoj?

Intraepidermal collection of neutrophils within spongiotic epidermis, characteristic of acute dermatophyte infection.

Why might granulomatous inflammation occur?

Seen in Majocchi granuloma (perifollicular infection) or when fungal elements are sparse and difficult to identify.

References

  1. Tinea Corporis – StatPearls — NCBI Bookshelf. 2023-10-25. https://www.ncbi.nlm.nih.gov/books/NBK544360/
  2. Tinea corporis: an updated review — PubMed Central. 2020-07-15. https://pmc.ncbi.nlm.nih.gov/articles/PMC7375854/
  3. Tinea corporis (Body Ringworm) — DermNet NZ. 2024. https://dermnetnz.org/topics/tinea-corporis
  4. Tinea Corporis (Body Ringworm) — Merck Manual Professional Edition. 2023. https://www.merckmanuals.com/professional/dermatologic-disorders/fungal-skin-infections/tinea-corporis-body-ringworm
  5. Tinea — Primary Care Dermatology Society. 2023. https://www.pcds.org.uk/clinical-guidance/tinea
Medha Deb is an editor with a master's degree in Applied Linguistics from the University of Hyderabad. She believes that her qualification has helped her develop a deep understanding of language and its application in various contexts.

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