Acquired smooth muscle hamartoma.

Congenital smooth muscle hamartoma usually manifests at birth, but rarely, can also appear later in life. It is usually located on the trunk and extremities and appears as variably‐sized papules, patches, or plaques.[3] Pseudo‐Darier’s sign is considered as the characteristic diagnostic clue for congenital smooth muscle hamartoma.[1] Pseudo‐Darier’s sign is a transient piloerection and elevation or induration of lesional skin, while Darier’s sign refers to the urtication and erythematous halo which is seen in response to stroking or rubbing of the lesional skin in cutaneous mastocytosis.[4]