RESUMO
Ringworm is very rarely found in the neonate, especially infants who have been confined from birth to an intensive care unit. We report an infection with the dermatophyte Trichophyton tonsurans, the most common cause of tinea capitis in children but not yet described in a premature baby who has never left the nursery. Our case illustrates the need to consider this diagnosis among the causes of dermatitis in the newborn, especially in at-risk populations such as indigenous Australians. Though our infant's presentation was the classic "ring" shape, a literature review revealed varied presentations. In contrast to the usual need for long-term antifungal medication, our case responded rapidly to a topical azole preparation. Although we did not screen visiting family members, screening would have been appropriate, and those found positive might have benefited from at least antifungal shampoo.