P66-T Skin sympathetic activity and autonomic studies in ross and harlequin syndrome

Abstract

Background Ross syndrome is a degenerative disorder characterized by the clinical triad of tonic pupil, hyporeflexia and segmental anhidrosis. Harlequin syndrome is described as segmental anhidrosis without ocular sympathetic deficit. Harlequin syndrome exhibits a selective abnormality in the peripheral skin sympathetic nerves and Ross syndrome reveals a widespread autonomic dysfunction. We present 4 patients with sudomotor dysfunction and different patterns of autonomic abnormalities. Material and methods Patients 1 and 2 complained of unilateral facial and upper limb flushing and sweating impairment. Patients 3 and 4 complained of an extensive anhidrosis and compensatory hyperhidrosis, patient 4 also presented an Adie’s pupil. Patients underwent nerve conduction studies, sympathetic skin responses (SSR), cardiovascular reflexes (deep breathing, Valsalva maneuver and standing) and laser evoked potentials. Results SSR were absent in the anhidrotic upper limb in patients 1 and 2, either to electric or laser stimuli. No evoked SSR responses were recorded in the four limbs in patients 3 and 4. Patient 4 presented slightly impaired cardiovascular reflexes and patients 2 and 4 presented mild abnormalities in sensory nerve conduction studies. Serologic screening, brain MRI and cervicothoracic CT were normal in all patients. Patients 1 and 2 were affected by a Harlequin syndrome, patient 3 presented an uncompleted Ross syndrome and patient 4 a classic Ross syndrome. Conclusions Ross and Harlequin syndrome are two clinically distinguishable expressions of partial dysautonomias belonging to a degenerative autonomic disorder that involves sympathetic, parasympathetic and myelinated nerve fibres with different distribution, extent and degree of impairment.