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Dermatophyte Infections

The above student authors generated this web page presentation as an assignment in Dr. Cooper’s Medical Mycology course at Youngstown

State University. Except for the indicated copyrighted material included within this electronic document, this web page is an intellectual

product of the above students and Dr. Cooper. This page may be used for educational purposes only. Any other use requires the

permission of the above authors as well as Dr. Cooper (crcooper01@ysu.edu).

Presentation Developed By: Jenee

Thurston, Brittany Seman and Adam

Speerstra

July 17, 2011 1 BIOL 4849: Medical Mycology

Tinea Capitis

Ringworm of the scalp

Etiologic Agent and Taxonomy

• M. Canis, T. Tonsurans, M. Nanum

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M. Canis T. Tonsurans M. Nanum

Kingdom Fungi Fungi Fungi

Division Ascomycota Ascomycota Ascomycota

Class Eurotiomycetes Eurotiomycetes Eurotiomycetes

Order Onygenales Onygenales Onygenales

Family Arthrodermataceae Arthrodermataceae Arthrodermataceae

Genus Microsporum Trichophyton Epidermophyton

Species M. Canis T. Tonsurans E. Floccosum

Electron Micrograph of M. Canis

Source:

http://www.superstock.com/stock-

photos-images/4102-5768

Tinea Capitis

Also known as “Herpes Tonsurans”, “Tinea

Tonsurans” or “Scalp ringworm”

Dermatophytic contagious fungal infection

of the scalp, hair follicles and hair shaft

Most common dermatophyte infection

worldwide

Caused by fungi of species genera

Trichophyton and Microsporum

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Most widespread in children

• Highest incidence among children aged 3-7

years

• Rare in adults

Symptoms:

• hairless patches on the scalp

• gray, scaly patches

• Little or no irritation

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Tinea Capitis

Figure: Child suffering from Tinea capitis Source: http://furiouspurpose.files.wordpress.com/2010/09/tinea-

capitis.jpg

Etiologic Agent and Taxonomy

• Microsporum (M.) canis (most prevalent), T.

tonsurans, M. namum, T. violaceum, T.

concentricum, and E. floccosum.

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Tinea Capitis

07/12/11 BIOL 4849: Medical

Mycology

M. canis Geographic Distribution

• Most prevalent in Western &

Southern Europe

• Italy

• Greece

• Germany

• Hungary and Poland also

report high rates of M. canis

tinea capitis in Europe Figure: European countries with high rates of M. canis

Source:http://www.enchantedlearning.com/subjects/continents/Euro

pe/label/labelanswers.GIF

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Mycology

M. canis Life Cycle

• Have asexual spores

known as mitospores

• Usually haploid and

dormant

• Mitospores may reproduce

the parent, or may also act

as gametes to fertilize a

well-matched partner

Figure: The life cycle of a typical acomycota

Source:www.scholars/biology/classification/fungi/ascomycota/

M. canis

Epidemiology

• In the late 19th and early 20th century, M. canis

and M. audouinii were the main agents in

Western and Mediterranean Europe

• Responsible for 60% of tinea capitis cases

• Most common agent of tinea capitis in

Mexico, Peru and Europe

• Increase in incidence rate

• Main reservoir of infection in cats

M. canis

Pathogenesis

• Common source of infection is from contact

with infected cats or guinea pigs

• Pathogens colonize in the fur of animals without

causing clinical symptoms to the animals

• Transmission by indirect contact with objects

• Car seats, stuffed animals, furniture

• Person-to-person contact

M. canis

Pathogenesis (cont....)

• Hair invasion occurs as an ectothrix or

endothrix infection.

• In ectothrix, the fungal spores attach to the surface

of the hair shaft

• In endothrix infections, the pathogen invades the

hair shaft without destroying the cuticle

Scalp Ringworm

Diagnosed by plain specimen (slides) and

fungal cultures

Symptoms include: • Scaly/erythematous lesions

• inflamed kerions

• seborrhea dermatitis

• pustules

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Inflamed kerion; www.healthhype.com/wp-

content/uploads/kerion_celsi15.jpg

Scalp Ringworm (cont.)

Treatments include both oral and topical

drugs • Oral: griseofulvin, terbinafine, itraconazole,

fluconazole

• Topical: Selenium sulfide, ketoconazole, shampoos

Prevention of Disease Reoccurance • Disinfect all skin-related objects (razors, headwear,

etc)

• Keep away from possible carriers, such as dogs, cats,

rabbits, guinea pigs

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Case Report 1: Columbus, OH

Analysis of pediatric patients at the Nationwide

Children’s Hospital; the study was on patients

who visited the Children’s Dermatology Clinic

from May 2001-May 2006; samples from the

scalp collected with hairbrush and further tested

for a positive culture of Tinea Capitis; a total of

189 patients had positive cultures; 88.9%

patients infected by T. tonsurans

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Case Report 2: North India

Study carried out by Departments of Dermatology

and Microbiology at pediatric hospital in New Delhi;

children 12 and up with suspected TC were studied

from April 2006-December 2008; skin scrapings and

hair fragments were taken from the patients and

collected on slides; 88.6% of patients had TC

caused by T. violaceum

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References

Coloe JR, Diab M, Moennich J, et. al. Tinea capitis among

children in the Columbus area, Ohio, USA. Mycoses 2009; 53:

158-162.

Coloe Susan, Baird Robert. Dermatophyte Infections in

Melbourne: Trends from 1961/64 to 2008/2009. j.1440-0960

2010; 4: 258-262

Fukuda Tomoo. Tinea Capitis.2011; 1: 7-13

Grover C, Arora P, Manchanda V. Tinea capitis in the pediatric

population: A study from North India. Indian Journal of

Dermatology, Venereology and Leprology 2010; 5: 527-532

Mahreen Ameen. Epidemiology of Superficial Fungal

Infections. j.clindermatol 2009; 2: 197-201

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