Which form of ringworm is marked by sulfur-yellow cuplike crusts on the scalp?

• A. Tinea favosa
• B. Tinea versicolor
• C. Tinea capitis
• D. Tinea nigra

Answer: (A)

The form of ringworm described by sulfur-yellow cuplike crusts on the scalp is a distinctive presentation of favus, a severe variant of tinea capitis. These crusts, called scutula, are yellow, cup-shaped, and cling to the hair shafts and scalp. They’re a hallmark feature that sets favus apart from other scalp infections. This form can lead to scarring and permanent hair loss if not treated.

In comparison, tinea versicolor causes pigmented patches mainly on the trunk and is due to Malassezia species, not crusted scalp lesions. Tinea nigra produces dark patches on the palms or soles, not the scalp. Tinea capitis is the general term for scalp ringworm, but the sulfur-yellow crusts specifically point to the favus variant.