![]() Grey patch: fine scaling of the scalp and patches of alopecia, which appear grey due to spores coating the affected hairs.Non-inflammatory variants of tinea capitis infection include the following. The clinical features may be broadly categorised into non-inflammatory and inflammatory variants. In all types, partial hair loss with some degree of inflammation is characteristic. What are the clinical features of tinea capitis?Ĭlinical features vary according to the species of dermatophyte, type of hair invasion, and the extent of the inflammatory host response. Clinically there is yellow crusting around the hair shaft. schoenleinii and characterised by clusters of hyphae at the base of the hairs, with air spaces in the hair shafts. Favus infection: a chronic dermatophyte infection caused by T.Fungal spores are retained inside the hair shaft, and the cuticle is not destroyed. Endothrix infection: the dermatophyte invades the hair shaft and grows within it. ![]() Fungal spores are evident on the outside of the hair shaft and the cuticle is destroyed. Ectothrix infection: the dermatophyte grows within the hair follicle and covers the surface of the hair.It penetrates the hair cuticle and typically invades the hair shaft in one of three ways: How does tinea capitis infection occur?įollowing invasion of the keratinised stratum corneum of the scalp (see structure of the normal skin), the fungus grows downwards into the hair follicle and the hair shaft. Zoophilic species can spread person-to-person. Zoophilic species are transmitted from infected animals, including household pets (especially kittens) or stray cats and dogs. Fomites that can harbour anthropophilic dermatophytes include hairbrushes, hats, towels, bedding, couches, and toys fungal spores may remain viable on these for months. Anthropophilic species are spread following contact with infected persons, including asymptomatic carriers, or contaminated objects (fomites). gypseum, originate in the soil and are rare causes of tinea capitis. violaceum is an anthropophilic fungus seen in New Zealand in patients who have migrated from Africa or the Middle East.Įxamples of other anthropophilic fungi that cause tinea capitis include: Trichophyton tonsurans is an anthropophilic dermatophyte that is the most common cause of tinea capitis in the United States. In New Zealand, Europe, and Asia the most common causative agent is the zoophilic species Microsporum canis which originates in cats.Įxamples of other zoophilic fungi that cause tinea capitis include: Dermatophytes may be classified into three broad categories, according to host preference: anthropophilic species (humans), zoophilic species (animals), and geophilic species (soil). While over 40 different species of dermatophytes are known to exist, only a small number are associated with tinea capitis. Tinea capitis is caused by dermatophytic fungi capable of invading keratinised tissue, such as the hair and nails. The introduction of antifungal agents, population movements, and improved hygiene practices are associated with evolving patterns of infection. Risk factors include animal contact, household crowding, lower socioeconomic status, warm humid environments, and contact sport. ![]() Tinea capitis is found in most parts of the world, although the prevalence of a particular fungal species causing tinea capitis varies geographically. It can also affect adults, particularly those who are immunocompromised. Tinea capitis predominantly affects preadolescent children, with incidence peaking between the ages of three and seven years. Click here for more images Who gets tinea capitis? ![]()
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