Which of the following conditions produce a positive Darier's sign?
High-Yield Explanation
Uicaria pigmentosa is the most common form of cutaneous mastocytosis presenting as reddish-brown monomorphic maculopapules, plaques or nodules appear in asymmetrical distribution anywhere on the body except the face, head, palms and soles. They uicate within a fewminutes of gentle rubbing (Darier's sign) & subsides within an hour. Telangiectasia macularis eruptiva perstan is a form ofcutaneous mastocytosis in adults presenting with red, telangiectatic macules, especially on the trunk, which tend not to uicate on rubbing. Other forms are mastocytoma & diffuse cutaneous mastocytosis. NB: darier's sign is also positive in juvenile xanthogranuloma and acute lymphoblastic leukaemia of neonates. Ref: Rook's textbook of dermatology, Edition-8, Page-22.31-32.