What are the types of tinea capitis? How is it treated?

Author: Li Houmin, Chief Physician, Peking University People's Hospital

Reviewer: Yang Rongya, Chief Physician, Seventh Medical Center, PLA General Hospital

Tinea capitis is a contagious disease caused by dermatophytes that infect the hair and scalp.

It can be transmitted through direct or close contact with sick cats, dogs and other animals, or through contact with contaminated combs, hats and other items, and should be taken seriously by everyone.

Clinically, tinea capitis can be divided into four types according to its different manifestations, namely white tinea capitis, black dot tinea, yellow tinea and pustular tinea.

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White ringworm is caused by fungi infecting and growing outside the hair, which will cause hair to break and break at a location about 3-5mm from the scalp. Outside the broken hair shaft, you can see the fungal sheath, which is a white sheath that wraps around the hair shaft. We can find the fungus at this fungal sheath and make a clear diagnosis.

The fungal infection in black dot ringworm grows inside the hair shaft, which makes the hair more brittle. After the hair grows out of the scalp, it cannot support growth and breaks immediately. Therefore, we can only see black spots on the scalp, which is called black dot ringworm.

The inflammatory reaction in kerion is severe, which is related to the fact that the infected dermatophytes are animal-loving or soil-loving fungi. After infecting the human body, they can cause disease and cause relatively serious inflammatory reactions, such as redness, swelling, pustules, papules and other manifestations.

Yellow ringworm is caused by a very special dermatophyte infection. The main clinical manifestations are yellow ringworm scabs with a special odor. It is now relatively rare in clinical practice.

In the past, due to poor hygiene and delayed medical treatment, the incidence of tinea capitis and yellow ringworm was relatively high. Even after the two types of tinea capitis were cured, the hair could not grow again, which would damage the appearance. Now, due to the improvement of living standards, medical treatment and treatment are more timely, the incidence of tinea capitis has decreased, and the prognosis has also improved a lot.

What everyone needs to understand is that tinea capitis should be differentiated from other skin diseases occurring on the scalp, such as seborrheic dermatitis, scalp psoriasis, trichotillomania or scarring alopecia.

The key point of identification is that tinea capitis will cause hair breakage, while other skin diseases on the scalp may cause erythema and hair loss, but no hair breakage.

In addition, if these diseases are to be identified through examination, the simplest method is fungal microscopy and culture. Finding the fungus is the most direct method of identification.

Seborrheic dermatitis is manifested by erythema and scales in the seborrheic area, but the scales are bran-like scales. The clinical description is mainly small and fragmented scales, and hair breakage generally does not occur.

In addition, seborrheic dermatitis may be accompanied by itching, obvious oil secretion, and easy recurrence. The causes are related to tension and the intake of greasy and spicy foods.

Scalp psoriasis manifests as scaly erythema on the scalp, which is more likely to occur in the hairline, such as the front hairline, the back hairline, or the side hairline. The scales that appear are sticky scales that can be scraped off layer by layer without breaking hair, but there will be tufts of hair, that is, tufts of hair. Scalp psoriasis may be accompanied by psoriasis rashes on other skin or nail psoriasis.

At present, the treatment principles of tinea capitis can be summarized into five points, namely cutting, washing, rubbing, dressing and disinfecting.

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Cutting means cutting hair, cutting it as short as possible to remove diseased hair.

Washing means washing your hair. Before using the medicine, you need to clean it first to remove scales and diseased hair. You can just wash your hair normally, or you can use some antifungal shampoo. The drug ingredients penetrate into the hair follicles through washing your hair, which can play a certain antifungal role.

To rub means to apply medicine, some external antifungal drugs.

Oral medication is used. Tinea capitis is different from other superficial fungal skin infections. It may not be completely eradicated by topical medications alone and must be treated with oral medications, such as terbinafine, itraconazole, etc.

Disinfection means disinfection. Tinea capitis is contagious, especially in some boarding schools, including kindergartens. It can be transmitted through combs, pillowcases, etc., so disinfection is also an important step.