Hyperkinetic movement disorders misdiagnosed as tics in Gilles de la Tourette syndrome

Abstract

Objective: To describe the gamut of movements misdiagnosed as tic exacerbations in Gilles de la Tourette syndrome (GTS) in a referral tertiary-care center.

Background: Movements seen in GTS can be classified as: (a) tics; (b) movements related to conditions associated with GTS, specifically obsessive-compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), and antisocial behaviors; and (c) movements secondary to treatment.

Methods: We reviewed a videotape database and patient records from a tertiary treatment center for GTS and collected GTS cases referred for disease exacerbation who had both tics and non-tic movements thought by the referring physician, the patient, and the family to be an exacerbation of tics.

Results: Of 373 GTS cases, 12 had movement disorders secondary to treatment, and six had non-tic movements related to conditions commonly associated with GTS. In the former group, there were 7 patients with acute akathisia, 3 with acute dystonia, 1 with tardive chorea, 1 with withdrawal emergent chorea, and 5 with tardive dystonia. Six had movement disorders related to non-tic conditions commonly associated with GTS: four patients had movements associated with OCD, one with ADHD and antisocial behavior, respectively.

Conclusion: There is a broad spectrum of movements in GTS that are not tics but can be misdiagnosed as tics. Clinical awareness of these movements is paramount to proper diagnosis and pharmacologic intervention.