Tourette syndrome

Tourette syndrome is a severe neurological movement disorder characterized by tics, which are involuntary, repeated, intermittent movements, or vocalizations. It is a genetic disorder that commonly presents in boys and is often associated with attention deficit hyperactivity disorder (ADHD) or obsessive-compulsive disorder (OCD). Diagnosis is based upon multiple motor tics and at least one vocal tic, lasting for longer than a year, and the exclusion of other suspected medical conditions. Treatment is symptomatic and includes behavioral therapy and dopamine antagonists. Approximately 50% of cases resolve by adulthood.

• Sex: ♂ > ♀ ^[1]
• Age of onset: usually 4–6 years of age (tics are most severe between 10–12 years of age and then decline during adolescence) ^[2]

Epidemiological data refers to the US, unless otherwise specified.

• Hypothesized to be a combination of environmental, social, psychological, and genetic factors
• Associated conditions
  • ADHD and/or OCD (most common)
  • Learning disabilities
  • Sleep disorders
  • Conduct disorder and oppositional defiant disorder
  • Mood and anxiety disorders

• Tics: sudden and rapid involuntary, intermittent, nonrhythmic movements or vocalizations without any recognizable purpose
  • Temporarily suppressible
  • An urge or sensation preceding the tic is relieved by its onset.

Tourette syndrome is a clinical diagnosis based on all of the following:

• Multiple motor tics and at least 1 vocal tic with a variable anatomical location, frequency, number, complexity, type, or severity over time
• Onset before 18 years of age
• Lasting > 1 year
• Not explained by other medical conditions or substance use (e.g., cocaine) ^[3]

• Other tic disorders ^[4]
  • Sporadic transient tic disorder: a subtype of tic disorder particularly common in children, which manifests with motor or vocal tics that occur over a period of less than one year before resolving.
    • Motor and/or vocal tics
    • Age of onset: < 18 years
    • Symptoms occur for less than 1 year (resolve spontaneously)
    • Not explained by any other medical conditions or substance abuse
    • Do not meet the criteria for Tourette syndrome
  • Persistent motor tic disorder or persistent vocal tic disorder are subtypes of tic disorder particularly common in children, which manifests with motor or phonic tics only.
    • Motor or vocal tics (not both)
    • Age of onset: < 18 years
    • Persist > 1 year
    • Not explained by any other medical conditions or substance abuse
    • Do not meet the criteria for Tourette syndrome
• Stereotypic movement disorder
  • Stereotypic, uncontrolled, repetitive movements lasting ≥ 4 weeks
  • More common in children, especially boys, with neurological disorders and developmental retardation
  • Includes rocking movements, hair pulling, hair twisting, and self-destructive behavior (e.g., head banging, picking at skin, hitting oneself) ^[5][6]
• Tardive dyskinesia
• Huntington disease

The differential diagnoses listed here are not exhaustive.

• Support: counseling and education (for both caregivers and patients)
• Behavioral therapy
  • Indicated for mild, nondisabling symptoms
  • Involves habit reversal training or Comprehensive Behavioral Intervention for Tics (CBIT)
• Medical therapy ^[7]
  • Indicated for severe or refractive cases despite behavioral therapy
  • Alpha-adrenergic agonists: guanfacine; (often first-line therapy), clonidine (very sedating)
  • Typical neuroleptic drugs: pimozide, haloperidol, fluphenazine (FDA-approved but may cause tardive dyskinesia)
  • Atypical neuroleptic drugs: risperidone (increasingly preferred because of fewer side effects)
  • Dopamine depleting drugs: tetrabenazine (may be used as first-line therapy to avoid side effects of neuroleptic drugs, i.e., dopamine blockade) ^[8]
• Deep brain stimulation (DBS): an alternative therapy in therapy refractory cases with severe tics ^[9]

Treatment of associated conditions (i.e., ADHD or OCD) can improve symptoms.

• Symptoms improve during adolescence. ^[2]
• May resolve spontaneously by 18 years of age (50% of cases) ^[10]

1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. DSM library ; 2013
2. Bloch MH, Leckman JF. Clinical course of Tourette syndrome.. J Psychosom Res. 2009; 67 (6): p.497-501. doi: 10.1016/j.jpsychores.2009.09.002 . | Open in Read by QxMD
3. Leckman JF, Zhang H, Vitale A, et al. Course of tic severity in Tourette syndrome: the first two decades.. Pediatrics. 1998; 102 (1 Pt 1): p.14-9. doi: 10.1542/peds.102.1.14 . | Open in Read by QxMD
4. Du JC, Chiu TF, Lee KM, et al. Tourette syndrome in children: an updated review.. Pediatrics and neonatology. 2010; 51 (5): p.255-64. doi: 10.1016/S1875-9572(10)60050-2 . | Open in Read by QxMD
5. Jones KS, Ramphul K. Tourette Syndrome And Other Tic Disorders. StatPearls. 2020 .
6. Ollendick TH, Hersen M. Handbook of Child Psychopathology. Springer Science & Business Media ; 2013
7. Freeman RD, Soltanifair A, Baer S. Stereotypic movement disorder: easily missed. Dev Med Child Neurol. 2010; 52 (8): p.733-738. doi: 10.1111/j.1469-8749.2010.03627.x . | Open in Read by QxMD
8. Pharmacology. https://www.tourette.org/research-medical/pharmacology/. . Accessed: May 15, 2017.
9. Thenganatt MA, Jankovic J. Recent advances in understanding and managing tourette syndrome. F1000Research. 2016; 5 : p.152. doi: 10.12688/f1000research.7424.1 . | Open in Read by QxMD
10. Savica R, Stead M, Mack KJ, Lee KH, Klassen BT. Deep brain stimulation in tourette syndrome: a description of 3 patients with excellent outcome.. Mayo Clinic proceedings. 2012; 87 (1): p.59-62. doi: 10.1016/j.mayocp.2011.08.005 . | Open in Read by QxMD