Harlequin syndrome--one face of many etiologies.

BACKGROUND: A 55-year-old woman presented to hospital with a 3-month history of asymmetric facial flushing of the skin during exertion, and an 18-month history of left-sided ptosis and miosis. Detailed medical history analysis revealed that a palpable node measuring 0.8 x 1.2 x 1.2 cm (volume 1.1 ml) had been discovered 2 years previously, within the left lobe of an otherwise uncomplicated goiter that had been successfully managed for 20 years. Otherwise, the patient was healthy. INVESTIGATIONS: Neurological examination, autonomic testing, duplex ultrasonography, scintigraphy and MRI. DIAGNOSIS: Harlequin syndrome following a lesion of the preganglionic sympathetic efferents, caused by neurovascular compression of the sympathetic chain between the stellate and superior cervical ganglion brought about by an elongated inferior thyroid artery. MANAGEMENT: Explanation of pathophysiology and benign nature of the condition.