Harlequin syndrome in a young girl: An opportunity to rethink the terminology.

Harlequin syndrome is a rare disorder of the autonomic nervous system, presenting as unilateral reduced flushing and sweating of the face induced by exercise, stress, or heat. It is caused by a cervical sympathetic deficit located at the preganglionic or postganglionic level on the non-flushing side. We present a case of an 8 year old with harlequin syndrome and review the other dermatological conditions for which the term "harlequin" is part of the nomenclature.