<prompt> Which of the following conditions produce a positive Dariers sign?Dariers diseaseUicaria pigmentosaHailey Hailey diseaseTelangiectasia macularis eruptiva perstans  <response>: 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 Dariers 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: dariers sign is also positive in juvenile xanthogranuloma and acute lymphoblastic leukaemia of neonates. Ref: Rooks textbook of dermatology, Edition-8, Page-22.31-32. 