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

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.