Idiopathic Harlequin Syndrome Manifesting during Exercise: A Case Report and Review of the Literature

Abstract

Harlequin syndrome is a rare autonomic disorder characterized by unilateral facial flushing and sweating with contralateral anhidrosis induced by exercise, heat, and emotion. It is usually idiopathic but could be the first manifestation of several serious underlying medical conditions. Medical or surgical treatments are not required for idiopathic Harlequin syndrome, but social and psychological factors may indicate sympathectomy or botulinum toxin injection. In this article, we report a case of idiopathic Harlequin syndrome and review the literature.

Idiopathic harlequin syndrome: a case report and literature review

“…The harlequin syndrome is then the expression of an abnormality of the sympathetic nervous system, originating from the T2-T3 roots or their nerve fibers, the site of the lesions may be at the level of sympathetic and parasympathetic nerve fibers of the stellate ganglion. It is a unilateral blocking of sympathetic innervation with absence of cutaneous vasodilatation and sweat secretion in response to a thermal, emotional or other stimulus [5]. This causes compensatory contralateral sympathetic hyperstimulation, explaining hypersudation with a flush.…”

Branch Retinal Vein Occlusion in Ipsilateral Harlequin Syndrome

“…Harlequin syndrome is a rare entity leading to decreased vasomotor and sudomotor activity with paleness and anhidrosis in the ipsilateral side of the face and excessive flushing and sweating on the contralateral side [7,8]. Most cases are idiopathic, but sometimes the denervation results from lesions of the sympathetic fibers after surgery or due to local or systemic diseases, such as brain stem infarction or diabetic vasculopathy.…”

Harlequin syndrome following upper lobectomy

“…Most of the vasomotor and sudomotor fibres involved in sympathetic innervation to the face arise from T2-3 and run together within the sympathetic chain, synapsing at the superior cervical ganglion, and then continue to their effectors via the carotid plexus. 2,4 Therefore, lesions in this region lead to loss of both flushing and anhidrosis, with the extent dependant on the site of the lesion. For example, complete hemifacial anhidrosis and loss of facial flushing indicates a lesion proximal to the superior cervical ganglion, resulting in contralateral compensatory facial flushing, whereas lesions distal to it will produce less extensive symptoms.…”

“…2,5,6 However, in severe cases, surgical sympathectomy, ipsilateral to the affected side of flushing, can be performed to prevent compensatory facial flushing. 2,5 Stellate ganglion blocks and botulinum toxin have been shown to have limited benefit in patients with persistent facial flushing. 2,5 This case report highlights a rare cause of Harlequin syndrome due to insertion of paravertebral block in thoracic surgery.…”

“…1 It is primarily idiopathic but can arise secondary to pathologies such as Guillain-Barre syndrome and diabetic neuropathy. 2,3 Seldom has the syndrome been associated with invasive procedures such as thoracotomy or paravertebral block. 3 We describe a rare manifestation of Harlequin syndrome after thoracic surgery.…”