Herald patch is seen in which of the following conditions: (AIIMS May 2013)
Pityriasis rosea is a papulosquamous eruption of unknown cause. Its first manifestation is the development of a 2 to 6 cm annular lesion known as the 'herald patch'.
Extra Edge: Pityriasis Rosea
1). In young adults, multiple oval salmon-pink plaques.
2). Herald patch+ (seen on trunk / upper arm / thigh).
3). Christmas tree pattern of distribution over trunk.
4). Mild SPONGIOSIS and focal exocytosis.
5). Skin folds give "fir-tree" like app. (spares palms & soles, unlike syphilis).
6). Centre of lesion is depressed with marginal collarette of scales.
7). Pruritus is absent or mild.