Tourette Syndrome



Tourette syndrome (TS) is a childhood-onset neurobehavioral disorder characterized by the presence of multiple motor and at least one phonic tic.

  • Tics are sudden, brief, repetitive, stereotyped motor movements (motor tics) or sounds (phonic tics) produced by moving air through the nose, mouth, or throat.
  • Patients can suppress their tics, but this often causes inner tension that eventually results in more forceful tics.
  • System(s) affected: nervous



  • Average age of onset: 7 years with greatest tic severity between 10 and 12 years (1)
  • Male > female (3:1); heterogeneous disorder, but non-Hispanic whites (2:1) compared with Hispanics and/or blacks

0.77% overall in children (1.06% in boys, 0.25% in girls)

Etiology and Pathophysiology

Abnormalities of dopamine neurotransmission and receptor hypersensitivity, most likely in the ventral striatum, play a primary role in the pathophysiology; may involve dysfunction of basal ganglia–thalamocortical circuits, likely involving decreased inhibitory output from the basal ganglia, which results in an imbalance of inhibition and excitation in the motor cortex

  • Thought to result from a complex interaction between social, environmental, and multiple genetic abnormalities
  • Controversial pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection (PANDAS); TS/OCD cases linked to immunologic response to previous group A β-hemolytic Streptococcus (GABHS)


  • Predisposition: frequent familial history of tic disorders and OCD
  • Recent studies suggest polygenic inheritance with evidence for a locus on chromosome 17q; sequence variants in SLITRK1 gene on chromosome 13q also are associated with TS.

Risk Factors

  • Risk of TS among relatives: 9.8–15%
  • Low birth weight, maternal stress, nausea/vomiting in 1st trimester, maternal smoking (2)

Commonly Associated Conditions

  • OCD (28–67%), ADHD (50–60%), conduct disorder, learning disabilities (23%)
  • Depression/anxiety including phobias, panic attacks, and stuttering; increased risk of contemplating suicide (1)
  • Impairments of visual perception, sleep disorders, restless leg syndrome, and migraine headaches
  • Cardiometabolic disorders, especially obesity, circulatory system diseases, type 2 diabetes (50%) (3)

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