Pityriasis Rosea

Synonyms

Roseola annulata; Pityriasis maculata et circinata; Pityriasis rubra aigu disséminé

Definition and Characteristics

Pityriasis rosea is an acute self-limited papulosquamous dermatosis that primarily affects children and young adults. The most common presenting sign is a herald or “mother” patch, which begins as a smooth, erythematous macule or papule, which expands over 1–2 weeks to form a round or oval, erythematous scaly lesion that is 1–10 cm in diameter [1]. A herald patch is found in 50–90% of cases [2]. Multiple herald patches are found in ∼5% of cases [3]. A generalized, bilateral, and symmetrical eruption develops about 1–3 weeks after the appearance of the herald patch (Fig. 1) The typical lesions are 5–10 mm, pinkish to brown, with a delicate collarette of scale at the periphery. The long axes are along lines of cleavage (Langer lines) (Fig. 1) [1,4].

Pityriasis Rosea. Figure 1

Pityriasis rosea. Note the generalized, bilateral and symmetrical eruption on the body of a...