Herald patch is an early lesion seen in which condition?

• A. Pityriasis rubra pilaris
• B. Pityriasis versicolor
• C. Pityriasis Rosea
• D. Lichen planus

Answer: (C)

Herald patch indicates pityriasis rosea. This early lesion is typically a single oval or round erythematous patch with a fine, collarette scale along its border, most often appearing on the trunk. It usually precedes a subsequent eruption by days to weeks, which then spreads in a characteristic Christmas-tree pattern down the trunk and proximal limbs. This patch helps distinguish pityriasis rosea from other common pruritic or scaly rashes. For example, pityriasis versicolor usually presents as multiple hypo- or hyperpigmented patches with fine scale scattered on the trunk rather than a solitary herald patch; pityriasis rubra pilaris shows widespread reddish plaques with follicular keratosis and islands of spared skin; lichen planus presents as pruritic, purple, polygonal papules with Wickham striae.