It is usually caused by dermatophytes (fungal infections of the skin affecting humans and animals) such as Trichophyton verrucosum, T. mentagrophytes,[1] and Microsporum canis.

Wood's lamp (blacklight) examination will reveal a bright green to yellow-green fluorescence of hairs infected by Trichophyton mentagrophytes var.

In a recent report, a previously well 9-year-old boy presented to the outpatients’ clinic with a tender, swollen occipital scalp lesion progressing over one month’s duration.

[citation needed] It was only after the scalp scrapings were examined, that the child was found to be having a local infection with the fungus Trichophyton tonsurans, which had resulted in kerion.

[citation needed] Unlike most other manifestations of Tinea dermatophyte infections, Kerion is not sufficiently treated with topical antifungals and requires systemic therapy.