skin health

Tinea Barbae

Generality

The tinea barbae (or ringworm of the beard) is a fungal infection that involves the skin surface of the face and neck, in areas where there are beards and mustaches.

Generally, this condition affects only adult men and most cases are sustained by dermatophyte fungi Trichophyton mentagrophytes and Trichophyton verrucosum .

Usually, tinea barbae involves the formation of superficial annular lesions, but can also lead to a deeper infection, similar to folliculitis. Sometimes, this dermatophytosis causes the onset of an inflammatory kerion, which can cause hair loss in the healing areas.

The diagnosis of tinea barbae is formulated on the basis of dermatological evaluation and microscopic, histological or cultural examination.

In mild cases, the treatment involves the use of topical medications (to be applied locally to the skin), but generally systemic antifungals (to be taken orally), such as griseofulvin, terbinafine and itraconazole are required. In the presence of severe inflammatory lesions, to help alleviate itching and pain, the doctor may also prescribe corticosteroids.

Causes

The tinea barbae is a dermatophytosis localized in the area of ​​the beard and mustache.

It is usually caused by fungi of the genus Trichophyton, which parasitize the stratum corneum of the epidermis and the keratinized cutaneous appendages, such as hair, nails and hair. Thanks to some enzymes, these keratinophilic and keratinolytic fungi are capable of lysing corneal skin structures, nails and hair, using demolition products as nourishment.

The mechanism at the base of the tinea barbae is similar to that of the tinea capitis: in both conditions, the invasion of hair, hair and hair follicles by dermatophytes induces an inflammatory response .

The species of fungi most commonly responsible for the onset of tinea barbae are:

  • Trichophyton mentagrophytes ;
  • Trichophyton verrucosum;

Less often, on the other hand, infections are due to:

  • Trichophyton violaceum;
  • Trichophyton rubrum;
  • Microsporum canis.

How the infection occurs

Tinea barbae is generally transmitted through direct skin contact :

  • From person to person;
  • From animals (cattle, dogs, cats, rabbits and mice) per person.

Factors that make it susceptible to infection include frequenting crowded places, poor personal hygiene and sharing pillows, razors, brushes, combs or other contaminated objects. Furthermore, tinea barbae may result from self-inoculation of dermatophytes responsible for concomitant onychomycosis or tinea pedis.

Predisposing factors

The tinea barbae has been observed more frequently in the past, before disposable razors were available: often, the infection was transmitted by barbers who used these professional tools, without observing the hygiene rules. For this reason, it is not surprising that the tinea barbae was once called "the barber's itch" .

Currently, tinea barbae is more common in rural areas and tends to occur more often in people living in countries where the climate is hot and humid; in these regions, zoophilic dermatophytes are the primary pathogens.

Who is most at risk

The infection affects almost exclusively adult and adolescent men, as it occurs in the areas of the face and neck where the beard is present.

Tinea barbae most often affects farmers and breeders who work with farm and farm animals.

Signs and symptoms

The clinical manifestations of tinea barbae are related to the pathogen responsible for the infections.

Generally, ringworm of the beard is manifested by superficial annular patches in the area of ​​the face and neck, but a deeper infection, similar to a folliculitis, can also occur. These lesions of varying sizes can be asymptomatic or associated with mild itching, dry skin flaking and / or nodular formations.

Often, the infection starts on the chin or neck, but in severely affected patients, the tinea barbae can cover the entire area of ​​the face where the beard is present.

Ringworm can also lead to the formation of a kerion, an inflammatory reaction that assumes a suppurative character and manifests itself as a roundish, raised patch covered with pustules and crusts; this lesion can cause permanent residual alopecia in the healing areas.

variants

The disorder can be distinguished in two forms:

  • Inflammatory tinea barbae : this type of ringworm of the beard is mainly caused by zoophilic dermatophytes and involves a deeper cutaneous involvement; the most common clinical presentation is kerion, but most patients also manifest multiple reddish plaques or solitary nodules, with pustules, exudate and crusts on the surface. The inflammatory variant of tinea barbae is usually localized on the chin, cheeks or neck, while the involvement of the upper lip is rare. Beard hair is fragile and shaving is easy and painless; at the level of the hair follicle, whitish lesions containing purulent material appear instead. This variety of tinea barbae is usually associated with generalized symptoms, such as regional lymphadenopathy, malaise and fever.
  • Non-inflammatory tinea barbae : this superficial form is caused by anthropophilic dermatophytes, such as T. rubrum . The disorder is less common and resembles the common tinea corporis or bacterial folliculitis (tinea barbae sicosiforme), due to the presence of erythematous patches and follicular papulo-pustular elements.

Possible complications

The prognosis of tinea barbae is usually good: inflammatory lesions tend to spontaneous remission within a few months; however, if not treated properly, they can cause permanent residual alopecia in the healing areas.

Non-inflammatory lesions of tinea barbae are more likely to become chronic and may not demonstrate a tendency to resolve spontaneously.

Diagnosis

The diagnosis of tinea barbae is formulated by the dermatologist on the basis of the anamnesis, clinical evaluation and microscopic, histological or cultural examination.

The dermatophyte responsible for the infection can be identified by direct microscopic analysis of fresh preparations of potassium hydroxide (KOH). Usually, the material to be examined consists of samples deriving from the scraping of the skin or from the removal by epilation of part of the hair on the face.

The culture survey allows to identify the genus and species of the responsible pathogen.

Ringworm of the beard is less common than tinea capitis (dermatophyte infection of the scalp).

Differential diagnosis

The tinea barbae must be distinguished from:

  • Seborrheic dermatitis;
  • Psoriasis;
  • Allergic contact dermatitis;
  • candidiasis;
  • Disidrosic eczema;
  • Erythema multiforme;
  • Erythrasma.

Treatment

The treatment of tinea barbae depends on the severity of the clinical manifestations, but usually involves the use of antifungal drugs to be applied to the skin (for example, shampoo, lotion or cream) or to be taken orally, based on the indications of the dermatologist specialist .

Generally, the treatment is based on the use of griseofulvin to be taken orally once a day, for 2-3 weeks after the disappearance of the clinical symptoms. On the other hand, some therapeutic protocols involve the use of systemic terbinafine and itraconazole.

If the lesions associated with tinea barbae are very inflamed, a short course of prednisone should be added to reduce the symptoms and the probability of healing.

Prevention and useful advice

Eliminating the source of infection responsible for tinea barbae is of great importance:

  • If agricultural workers become infected, all animals should be examined to check for fungal skin lesions.
  • Treatment of other fungal infections of the skin, such as tinea pedis or onychomycosis, can prevent the spread of infection by self-inoculation.