Tics — Tics are the clinical hallmark of TS. Tics are sudden, brief, intermittent movements (motor tics) or utterances (phonic tics). Tics have been considered involuntary, but tics can temporarily be voluntarily suppressed. Most patients with TS also have comorbid problems such as attention deficit hyperactivity disorder (ADHD) or obsessive-compulsive disorder (OCD).
Tic classification — The tics in TS can be categorized as motor or phonic (ie, vocal), and as either simple or complex.
●Motor tics – Simple motor tics include eye blinking, facial grimacing, shoulder shrugging, and head jerking. Complex motor tics involve sequences of coordinated movements, including bizarre gait, kicking, jumping, body gyrations, scratching, seductive gestures, copropraxia (obscene gestures), and echopraxia (mimicking of gestures). Some motor tics may be dystonic; examples include oculogyric movements, sustained mouth opening, torticollis, and body postures. Other motor tics may be tonic in nature; examples include immobility, staring, and prolonged contraction of abdominal muscles.
Violent or forceful neck tics in patients with TS rarely have been associated with injuries including cervical disc herniation, compressive and noncompressive myelopathy, and cervical artery dissection with stroke. Thus, some experts advocate more aggressive management of severe forceful neck tics, including the use of botulinum toxin injections or even deep brain stimulation.
●Phonic tics – Simple phonic tics include grunting, barking, moaning, throat clearing, hollering, and other noises. Complex phonic tics include coprolalia (obscene words), echolalia (repetition of words), and palilalia (repetition of a phrase or word with increasing rapidity). Coprolalia occurs in approximately 40 percent of cases.
Tic characteristics — One of the most characteristic features of tics is the presence of premonitory feelings or sensations, which are relieved by the execution of the tic – the irresistible urge before and relief after a tic. Other tic characteristics include the presence of precipitating factors, temporary suppressibility, variable severity, a waxing and waning nature, and evolution of an individual’s tic repertoire over time.
Diagnostic criteria:
There is no confirmatory laboratory test for TS; the diagnosis is based on a set of clinical diagnostic criteria:
- Both multiple motor tics and one or more phonic tics must be present at some time during the illness, although not necessarily concurrently
- Tics must occur many times a day, nearly every day, or intermittently throughout a period of more than one year
- Anatomical location, number, frequency, type, complexity, or severity of tics must change over time
- Onset of tics before the age of 18 years
- Involuntary movements and noises must not be explained by another medical condition (or by the physiological effects of substances as per the DSM-5)
- Motor tics, phonic tics, or both must be witnessed by a reliable examiner at some point during the illness or be recorded by videotape or cinematography
Treatment
- Patients with TS who have tics that are mild and nondisabling should receive education, counseling, and supportive care; behavioral or pharmacologic tic suppression therapy is not clearly indicated.
- For patients with TS and tics that are causing psychosocial, physical, functional, or other problems, we suggest habit reversal training with Comprehensive Behavioral Intervention for Tics (CBIT). When CBIT is not an option for patients with TS and debilitating tics, we suggest medication treatment with tetrabenazine. Alternatives include fluphenazine or risperidone. For patients with TS who have only focal motor or phonic tics, we suggest treatment with botulinum toxin injections into the affected muscles.