About tinea capitis
Tinea capitis is a superficial dermatophytic fungal infection of the scalp, usually caused by Tricophyton tonsurans, Microsporum canis, or Microsporum audouinii. Clinically, the disease ranges from scaling patches to a boggy, inflamed, pustule-studded plaque (kerion) accompanied by regional lymphadenopathy (swelling of lymph nodes). Patchy alopecia (hair loss) studded with broken hair shafts, caused by some fungal species, can create an appearance termed “black dot” ringworm. The disease is common in school-age children, occurring in epidemics.
With what can tinea capitis be confused?
The differential diagnosis of tinea capitis depends on the degree of inflammation present. Minimally inflamed scale can appear similar to seborrheic dermatitis. Inflammation, can result from scalp infection (cellulitis). Areas of patchy hair loss can be confused with alopecia areata or trichotillomania. Residual scarring can be confused with hair loss from discoid lupus erythematosus.
How is tinea capitis diagnosed?
There may be a history of a family member, classmate, or pet with patchy hair loss. Most cases of tinea capitis are due to Tricophyton tonsurans, especially in African Americans. Unlike Microsporum canis and Microsporum audouinii, Tricophyton tonsurans does not fluoresce under Wood’s lamp (ultraviolet light) examination, limiting the usefulness of this investigation. A diagnosis must be made by KOH preparation and culture of broken hair shafts (not just scale, which may have a low diagnostic yield). Biopsy is not usually required.
How is tinea capitis treated?
Topical antifungal agents are not effective in treating tinea capitis. Systemic therapy is required with antifungals such as griseofulvin, terbinafine or itraconzole. Shampooing with an antifungal shampoo (e.g. 2.5% selenium sulfide, 2% ketoconazole, or 1-2% zinc pyrithione) may be helpful as well, and should be used prophylactic ally by close contacts.
What is the prognosis for tinea capitis?
With systemic treatment, tinea capitis usually resolves in several months. Untreated, some cases will resolve spontaneously over months, while others may last for years. In children, resolution often occurs with puberty, even without treatment. Severe inflammatory disease can led to scarring and permanent hair loss.
Further information on tinea capitis
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