Harlequin syndrome is a rare autonomic nervous system disorder characterized by sudden unilateral flushing of the face, neck, chest, and arm, with sweating on the contralateral side, exacerbated by stress, exercise, heat, and spicy foods. It results from disruption of the sympathetic pathways and can overlap with other dysautonomic conditions. While the cause is often idiopathic, it can also be iatrogenic or secondary to other neurological disorders.

1. Ade Wijaya, MD – October 2022

2.  A rare autonomic disorder
 Dysruption of symphatetic pathways
Algahtani, H.; Shirah, B.; Algahtani, R.; Alkahtani, A. Idiopathic Harlequin Syndrome Manifesting during Exercise: A Case Report and Review of the Literature. Case Rep. Med. 2017,
2017, 5342593.
Biondi, A.; Persiani, R.; Zoccali, M.; Rausei, S.; Cananzi, F.; D’Ugo, D. Harlequin syndrome. Ann. Thoracic Surg. 2009, 88, 304

3. Mavroudis I, Balmus IM, Ciobica A, Luca AC, Chowdhury R, Iordache AC, Gorgan DL, Radu I. Mini-Review on the Harlequin Syndrome—A Rare Dysautonomic Manifestation Requiring
Attention. Medicina. 2022 Jul 15;58(7):938.

4.  Sudden unilateral flushing of the face, neck,
chest, and arm, concurrent with contralateral
anhidrosis exacerbated by stress, emotional
reactions, exercise, heat, and spicy foods
 Cluster headaches
 Overlap with other syndromes disruptive to
the idiopathic nerve pathways (Horner
syndrome, Ross syndrome, and/or Adie
syndrome)
Tascilar, N.; Tekin, N.S.; Erdem, Z.; Alpay, A.; Emre, U. Unnoticed dysautonomic syndrome of the face: Harlequin syndrome. Auton. Neurosci. 2007, 137, 1–9.
Algahtani, H.; Shirah, B.; Algahtani, R.; Alkahtani, A. Idiopathic Harlequin Syndrome Manifesting during Exercise: A Case Report and Review of the Literature. Case Rep. Med. 2017,
2017, 5342593.

5. Mavroudis I, Balmus IM, Ciobica A, Luca AC, Chowdhury R, Iordache AC, Gorgan DL, Radu I. Mini-Review on the Harlequin Syndrome—A Rare Dysautonomic Manifestation Requiring
Attention. Medicina. 2022 Jul 15;58(7):938.

6.  A rare neurological disorder
 Affecting the face and neck autonomic
nervous system
 Idiopathic, iatrogenic, or secondary
 Affecting both adults and children
 In many cases, the symptoms remit with no
treatment