Pityriasis rosea. This benign and self-limited eruption occurs most often in spring and autumn. Most patients are adolescents and young adults, but the disorder is not unusual in children and may even occur during infancy. In its classic form, pityriasis rosea follows a specific and predictable clinical course. The first solitary lesion is a circle or oval of erythema and scaling. As it develops to its full size of up to 2–3 cm, this so-called herald patch may easily be mistaken for a lesion of tinea corporis. The chest and upper thigh are common locations for the herald patch but any area may be involved. A typical herald patch is shown here.
Color Atlas of Pediatric Dermatology
Samuel Weinberg, Neil S. Prose, Leonard Kristal
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