The Semiology of Tics, Tourette's, and Their Associations

Abstract

Gilles de la Tourette syndrome (GTS) is a prototypical neuropsychiatric disorder breaking the boundary of disciplinary dualism between neurology and psychiatry. The diagnosis of GTS is clinical and, in most cases, straightforward. Tics as a hallmark of GTS are usually easy to recognize and distinguish from other movement disorders as fragmented, repetitive, exaggerated movements resembling normal motor behavior, but appearing out of context. In complex cases, knowledge on additional characteristics and signs as, for example, tic distribution, suggestibility, voluntary tic inhibition, and presence of echo- or paliphenomena might further aid clinical diagnosis. However, although defining GTS, tics are rarely the main issue. The presence of comorbidities and coexisting psychopathologies often hampers normal development and negatively affects quality of life. Their recognition and treatment is paramount. Here, we review existing literature and provide a comprehensive update on the multifarious aspects of the movement disorder and neuropsychiatry of GTS. We also provide a list of associated movement disorders known to occur in GTS patients and discuss differential diagnoses to be considered in atypical cases. We finally comment on available treatment options.

Keywords: Gilles de la Tourette syndrome; tics.

Figure 1

Simplified scheme of the relation between tic severity and associated psychopathology. Although echo‐ and paliphenomena may appear in the entire spectrum of chronic tic disorders (CTD), coprophenomena are associated with more severe phenotypes and the presence of multiple psychopathologies. ASD, autism spectrum disorder; ADHD, attention deficit hyperactivity disorder; GTS, Gilles de la Tourette syndrome; NOSI, non‐obscene socially inappropriate behavior; OCB/OCD, obsessive‐compulsive behavior/disorder; SIB, self‐injurious behavior.

Figure 2

List of differential diagnoses of tics on grounds of phenomenology. FBDS, faciobrachial dystonic seizures; PKD, paroxysmal kinesigenic dyskinesia; PTU, paroxysmal tonic upgaze; RLS, restless legs syndrome.