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7/17/2011
1
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 ([email protected]).
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
July 17, 2011 2 BIOL 4849: Medical Mycology
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
July 12, 2011 3 BIOL 4849: Medical Mycology
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
07/12/11 BIOL 4849: Medical Mycology 4
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.
07/12/11 BIOL 4849: Medical Mycology 5
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
7/17/2011
2
07/12/11 BIOL 4849: Medical
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
July 17, 2011 BIOL 4849: Medical Mycology 11
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
July 17, 2011 BIOL 4849: Medical Mycology 12
7/17/2011
3
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
July 17, 2011 BIOL 4849: Medical Mycology 13
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
July 17, 2011 BIOL 4849: Medical Mycology 14
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
July 17, 2011 BIOL 4849: Medical Mycology 15