SITE OF AUTONOMIC DEFICIT IN HARLEQUIN SYNDROME - LOCAL AUTONOMIC FAILURE AFFECTING THE ARM AND THE FACE

The site of autonomic deficit was investigated in 4 patients with loss of thermoregulatory flushing and sweating on one side of the face but no associated miosis (harlequin syndrome). In 2 patients the sudomoto r deficit included the hand. Signs of postganglionic sympathetic defic it included pathological lacrimal sweating (2 patients) and supersensi tivity to 1% phenylephrine eyedrops (3 patients). One or both pupils c onstricted excessively to 0.0625% pilocarpine eyedrops (3 patients), c onsistent with ocular parasympathetic deficit. These findings suggest that pre- or postganglionic cervical sympathetic fibers, and parasympa thetic neurons in the ciliary ganglia, are compromised in harlequin sy ndrome. The finding of cholinergic supersensitivity in the iris muscle s of patients with harlequin syndrome indicates a relationship with Ho lmes-Adie syndrome, Ross's syndrome, and the persistent autonomic defi cit occasionally associated with Guillain-Barre syndrome.