tourette's%20syndrome%20-and-%20other%20tic%20disorders
TOURETTE'S SYNDROME & OTHER TIC DISORDERS
Tics are sudden, rapid, non-rhytmic, repetitive, motor movements or vocalizations. The mean age of onset is approximately 5 years old.
Tourette's syndrome is the most common form of tic disorder.
There is a strong genetic component showing a 10- to 100-fold increase in the rates of tics and Tourette's syndrome among first-degree relatives of Tourette's syndrome patients.
Simple motor tics are restricted to a single or a few muscle groups and last less than a fraction of a second.
Complex motor tics involve larger muscle groups, usually last longer and appear purposeful and goal-directed.

Tourette's%20syndrome%20-and-%20other%20tic%20disorders Diagnosis

Diagnosis

  • There are 3 types of tic disorders based on DSM-5 criteria

Tourette's Disorder

  • Presence of both multiple motor tics and at least 1 vocal tic during the course of illness, although they may not occur at the same time
  • The tics may increase and decrease in frequency but have continued for >1 year since the first tic occurred
  • Tics started before 18 years of age
  • Symptoms are not due to effects of any substance (eg cocaine) or caused by any other medical condition (eg Hungtington’s disease or postviral encephalitis)
Persistent (Chronic) Motor or Vocal Tic Disorder
  • Presence of either one or more motor or vocal tics during the course of the illness
  • The tics may increase and decrease in frequency but have continued for >1 year since the first tic occurred
  • Tics started before 18 years of age
  • Symptoms are not due to effects of any substance (eg cocaine) or caused by any other medical condition (eg Hungtington’s disease or postviral encephalitis)
  • The patient has not been diagnosed with Tourette’s disorder
  •  Specify if the disorder has motor tics only or vocal tics only
Provisional Tic Disorder
  • Presence of one or more motor and/or vocal tics
  • The tics persisted for <1 year since the first tic occurred
  • Tics started before 18 years of age
  • Symptoms are not due to effects of any substance (eg cocaine) or caused by any other medical condition (eg Hungtington’s disease or postviral encephalitis)
  • The patient has not been diagnosed with Tourette’s disorder or persistent (chronic) motor or vocal tic disorder

Classification

  • Tics may be classified based on:
    • Type
      • Motor: Fragments of normal motor movements appearing out of context and arise in the voluntary musculature involving discrete muscles or group of muscles
      • Vocal or phonic: Noise produced by movement of air through the nose, mouth or pharynx
      • Sensory: These are premonitory sensations that precede tics characterized as unpleasant somatosensory sensations and often relieved by execution of the tic
      • Cognitive: These are repetitive thoughts that occur as a response to excessive urge to act upon provocative visual, auditory, tactile or inner stimuli, often called as impulsions
    • Complexity - simple or complex
    • Isolated (same anatomical location) or multiple locations
    • Location, number, frequency
    • Duration
      • Clonic: Tics are <100 milliseconds
      • Dystonic: Tics are >300 milliseconds, characterized by abnormal posture
      • Tonic: Tics are >300 milliseconds, characterized by isometric contraction

Simple Tics

  • Simple motor tics are restricted to a single or a few muscle groups and last less than a fraction of a second
    • Eg eye blinking, nose wrinkling, neck jerking, shoulder shrugging, facial grimacing, abdominal tensing
  • Simple vocal tics are elementary sounds
    • Eg throat clearing, grunting, sniffling, snorting

Complex Tics

  • Complex motor tics involve larger muscle groups, usually last longer, and appear purposeful and goal-directed
    • Eg Copropraxia (repetitive obscene movements), echopraxia (mimicking others), self-injurious behavior, hand gestures, jumping, pressing, stomping, facial contortions, repeatedly smelling an object
  • Complex vocal tics occur when sounds are elaborate or have a semantic content
    • Eg Palilalia (repeating one’s own words), echolalia (repeating another’s words or phrases), coprolalia (use of obscene words)

Common Comorbid Conditions Found in Patients with Tourette's Syndrome

  • Attention-deficit/hyperactivity disorder (ADHD) 
  • Obsessive-compulsive disorder (OCD)
  • Learning, developmental & disruptive behavioral disorders

Please see Attention-Deficit/Hyperactivity Disorder & Obsessive-Compulsive Disorder Disease Management Charts for detailed information concerning medications used for treatment

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