Tourette syndrome

What is Tourette's Syndrome?

Tourette's syndrome is a brain and nervous system movement disorder characterised by involuntary, jerky, and repetitive movements or actions in any part of the body. It also includes sounds produced in children between the age group of 2 to 15 years.

Associated anatomy

Tourette's syndrome occurs when there is an imbalance or disconnection between basal ganglia in the brain and the nerves connecting it to the nervous system.

Causes

• Idiopathic: No known definite reason has been recognised as a cause of Tourette's syndrome. 
• Hereditary: This disorder may be passed on to family members with known history. Children whose parents had Tourette's syndrome are more prone to acquire it. Symptoms may vary among the family members.
• Genetic: Researchers have found that genes and their mutations may play an important role in causing Tourette's syndrome.

Signs and Symptoms

Signs:

The treating doctor may look for the age of symptom onset, pattern and duration of symptoms. Certain triggering factors may provoke such tics that may prove helpful for the physician to diagnose Tourette's syndrome. These include seeing or hearing someone clear their throat or sniff, tight clothes, anxiety, and excitement.

Tics can also be classified as simple and complex. Simple tics involve a few muscles and a particular action. Whereas complex tics include complex patterns of movements involving multiple muscle groups.

Symptoms:

• Motor tics: Motor signifies movement-related tics like hand gestures or movements, winking, sniffing or jerking.

• Vocal tics: Vocal indicates voice-related tics such as swearing, making repetitive sounds, words, clearing throat, or coughing sounds.

Treatment

Many cases have mild symptoms that do not need special attention, but few require medications to suppress the symptoms. Some exceptional cases may resolve spontaneously.

• Medications: Drugs that block dopamine may help reduce tics or completely suppress them. Other drugs include stimulant medications and antidepressant drugs in cases where attention deficit hyperactivity disorder and depression co-exist.
• Cognitive behavioural therapy: Individuals with socially unacceptable symptoms may be trained to control their trigger tics and symptoms through behaviour therapy. Biofeedback also proves to be beneficial in most cases.
• Psychotherapy: Sessions with a psychologist can help control attention deficit hyperactivity disorder, depression and other associated problems.

Ongoing clinical trials are trying to find the efficacy of other treatment approaches such as brain stimulation, and genetic studies are also being undertaken.

Risk factors

• Family history of tics: Children whose parents or close relatives have tic disorder are prone to develop it at growing ages. It is a relatively modifiable risk factor with proper genetic counselling.
• Environmental tic triggers: Certain unavoidable triggers near a child with Tourette's disorder may aggravate symptoms.
• Males are at a greater risk of developing tic disorder than females.
• School-age children, particularly those in the age group of 5-15 years, are at higher risk than adults.
• Genes: Many children with congenital anomalies or abnormalities are at risk of genetic mutation to develop tic disorder

Diagnostic Test

There is no need for any laboratory or diagnostic test for Tourette's syndrome. Sometimes, an MRI, EEG, CT scan may be advised to rule out other disorders that may mimic or cause similar symptoms.

Prevention

Primary Prevention

Genetic counselling: Parents and family members are recommended to undergo genetic counselling wherein counsellors explain the possibilities of having a child with similar disorders and how to overcome or prevent this situation.

Secondary Prevention

• Child support groups: Many groups are available that help in the rehabilitation and counselling of individuals and children associated with Tourette's syndrome.
• Peer group and teacher counselling: Peers, friends, teachers, bus drivers and all those in contact with the child can be trained on how to behave and control a child with this disorder.
• Cognitive behavioural therapy for the child may help control the initial warning signs of the onset of a tic.

Alternate Name

Movement disorders, tics, tic disorder.

Differential Diagnosis

Signs and symptoms of Tourette's syndrome are similar to many other hyperactivity movement disorders such as chorea, seizures, myoclonus and paroxysmal dyskinesia. Other psychological disorders such as depression, ADHD and Obsessive-compulsive disorder may mask the tics and become difficult to diagnose when present together. At an early stage, tics may go unnoticed and do not prompt medical attention. When the tics become socially unacceptable, they need medicines and other therapies.

Epidemiology

• Gender: Male: Female ratio stands at 4:1
• Age group: Occurs in 2-15 years of infants and school-going children
• Family history of tics and associated disorders play an important role.
• Individuals' race and colour do not predispose one to develop Tourette's syndrome

Expected prognosis

The symptoms of Tourette's syndrome usually subside into adulthood, with mild symptoms present occasionally.

Natural Progression

There is no absolute cure for Tourette's syndrome. Individuals with this disorder usually have a good life expectancy with all abilities as normal adults.

Pathophysiology

Tics do not involve any significant changes occurring elsewhere in the body, but associated comorbidities may cause changes. Long-term tics may become incapacitated for an individual that may manifest into social and physical disabilities.

Possible complication

There are no known complications associated with this disorder, but co-existing psychological and growth abnormalities may worsen tics and other symptoms.