Congenital Harlequin syndrome as an isolated phenomenon: A case report and review of the literature.

UNLABELLED: Harlequin syndrome (HS) is a rare autonomic disorder due to a hemifacial cutaneous sympathetic denervation. It is characterized by unilateral diminished sweating and flushing of the face even though after heat or prolonged exercise. It is typically acquired. Congenital cases only represent a 6% of all individuals with HS. All congenital HS cases reported so far showed a concomitant Horner syndrome, probably due to a stellate ganglion involvement. HS represents an uncommon autonomic disorder due to a hemifacial cutaneous sympathetic denervation. It is clinically characterized by a dramatic alteration in facial appearance: ipsilateral denervated pale and dry half from the other intact red and moist half. CONCLUSION: We present, to the best of our knowledge, the first case of a patient with a congenital HS as an isolated phenomenon.