Clinical image: The Harlequin sign—benign blush or the bearer of bad news?



Illustration 1.

The patient, a 41-year-old woman, presented to the rheumatology clinic. She reported that, for the past 3 years, she experienced unilateral facial flushing and coldness of the ipsilateral hand after vigorous exercise. Results of the neurologic assessment, including tests for autonomic function, were normal. Findings of magnetic resonance imaging of the patient's brain, neck, thoracic outlet, and chest were also normal. The patient mentioned that her son experienced similar symptoms, although he had not been formally assessed. A diagnosis of Harlequin syndrome was made in light of the patient's characteristic symptoms, which included unilateral flushing and hyperhidrosis after exercise (Wasner G, Maag R, Ludwig J, Binder A, Schattschneider J, Stingele R, et al. Harlequin syndrome—one face of many etiologies. Nat Clin Pract Neurol 2005;1:54–9). Harlequin syndrome results from disruption of sympathetic fibers at or distal to the sympathetic ganglia at T2–T3, with proximally located lesions associated with greater autonomic dysfunction. To date, 91 patients with Harlequin syndrome have been reported, and in 64% of these no cause was identified. In the remaining patients, mediastinal tumors, paravertebral thoracic blocks, and neck-mass resection accounted for the majority of the cases. In some cases of Harlequin syndrome there may be a generalized disorder of the autonomic nervous system constituting part of a spectrum of conditions involving generalized dysautonomia, such as Ross syndrome and Adie syndrome. Coldness of the ipsilateral arm, suggestive of multifocal involvement, was mentioned in only 1 other case report (Moon SY, Shin DI, Park SH, Kim JS. Harlequin syndrome with crossed sympathetic deficit of the face and arm. J Korean Med Sci 2005;20:329–30). Hereditary Harlequin syndrome has not yet been described. Management involves ruling out structural lesions in the paravertebral region, after which education, reassurance, and procedures to improve cosmesis form the mainstay of therapy.