Kerion

What is a kerion?

A kerion is a abscess caused by fungi infection. It occurs most frequently on the scalp (tinea capitis), but can also arise anywhere exposed to the fungus, such as the face (tinea faciei) and upper extremities (tinea corporis). It is often misdiagnosed as bacterial infection.

What does a kerion look like?

A kerion presents as a pus-filled lump, often several centimeters in diameter. It is characterized by marking inflammation. The hairs within the kerion are loose and fall out, often resulting in a bald area (located alopecia)

Regional expansion lymph nodes can occur, and some people become systemically ill with fever and discomfort. It can be followed by a extended itchy eczema-I like it eruption (dermatophytida).

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What causes kerion?

A kerion is caused by a dramatic immune response to a dermatophyte fungal infection (ringworm). The most common fungi found on kerion are:

• Microsporum canis
• Trichophyton tonsurans
• Trichophyton verrucosum
• Trichophyton mentagrophytes

Trichophyton rubrum is not a common cause of kerion.

How is kerion diagnosed?

Suspicion is increased due to the typical appearance of a kerion. Exam using a Wooden lamp Long wavelength UVA emission may reveal yellow-green fluorescence if the kerion is due to Microsporum canis, but is often negative even when this is responsible. organism because inflammation obscures the presence of the fungus.

To confirm the diagnosis, scrapings and hair Samples can be taken from the affected area to microscopy and mushrooms culture (laboratory tests for fungal infection). A bacterial swab should be considered a secondary infection with bacteria It is common.

Is Kerion contagious?

Yes, fungal infection can be transmitted by kerion to other household members if they are in close contact, especially if they share bedding and towels. Combs and hair brushes should be disinfected or discarded to prevent the transmission of infection or reinfection.

Since the fungus that causes kerion (for example, M canis) often resides in a home pet (e.g. kitten), family members can also become infected through direct contact with the animal.

What is the treatment of kerion?

Kerion should be treated with oral antifungal agents. A 6-8 week course of treatment is usually prescribed as a minimum. Current antifungal agents are not effective due to deep fungal invasion into the hair follicle.

• Terbinafine
• Itraconazole

• Griseofulvin (no longer available in New Zealand)

Antibiotics may be needed if bacterial infection is present. Antifungal shampoos containing ketoconazole orciclopirox help reduce the risk of spreading the infection to others.

Hair usually grows back after the infection is treated, but sometimes hair loss is permanent, especially if the infection has been prolonged.