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Back In 1825 A French doctor, Jean Marc Gaspard Itard, reported the first case of Tourette syndrome describing Marquise de Dampierre, an important woman of nobility in her time with body tics, barking sounds, and uncontrollable utterances of obscenities. Sixity years later Jean-Martin Charcot, an influential French physician, assigned his resident Georges Albert Édouard Brutus Gilles de la Tourette, a French physician and neurologist, to study patients at the Salpêtrière Hospital, with the goal of defining an illness distinct from hysteria and from chorea and he added 8 more patients. Gilles de la Tourette noted that all 9 patients shared one common feature; they all exhibited brief involuntary movements or tics. An additional 6 patients made noises, 5 shouted obscenities (coprolalia), 5 repeated the words of others (echolalia), and 2 mimicked others' gestures (echopraxia). Although Gilles de la Tourette considered the disorder that he described to be hereditary, the etiology was ascribed to psychogenic causes for nearly a century following the original report.
The view of TS as a life-long disorder, once held as a certainty, has changed considerably in the past 2 decades. In most cases, tics are known to ebb in severity and are not problematic by the adult years; however, this discovery has been accompanied by the realization that TS is a far more complex disorder than originally was conceptualized. The association of tics with OCD and ADD symptomatology and with several other impulse control disorders has caused TS to be investigated as a model neuropsychiatric disorder and has raised more questions than it has answered.
1- What is tourette syndrome ?
It is an inherited neurological disorder with onset in childhood, characterized by the presence of multiple physical (motor) tics and at least one vocal (phonic) tic; these tics characteristically wax and wane. Tourette's is defined as part of a spectrum of tic disorders, which includes transient and chronic tics.
2- alternative names :
also called Tourette's syndrome, Tourette's disorder, Gilles de la Tourette syndrome, GTS or, more commonly, simply Tourette's or TS
3- causes and risk factors :
The exact cause of Tourette's is unknown, but it is well established that both genetic and environmental factors are involved. Genetic studies have proved that the overwhelming majority of cases of Tourette's are inherited, although the exact mode of inheritance is not yet known, and no gene has been identified. In some cases, tics may not be inherited; these cases are identified as "sporadic" Tourette syndrome (also known as tourettism) because a genetic link is missing.
A person with Tourette's has about a 50% chance of passing the gene(s) to one of his or her children, but Tourette's is a condition of variable expression and incomplete penetrance. Thus, not everyone who inherits the genetic vulnerability will show symptoms; even close family members may show different severities of symptoms, or no symptoms at all. The gene(s) may express as Tourette's, as a milder tic disorder (transient or chronic tics), or as obsessive compulsive symptoms without tics. Only a minority of the children who inherit the gene(s) have symptoms severe enough to require medical attention. Gender appears to have a role in the expression of the genetic vulnerability; males are more likely than females to express tics.
However, recent information suggests that the pattern of inheritance may be more complicated than previously was thought. For example, bilinear transmission, involving both the maternal and paternal sides, is common in families with TS and may be related to the severity of symptoms. Therefore, polygenic influences possibly are important, with clinical expression being determined by the number of susceptibility loci that are inherited from either the mother or father.
Non-genetic, environmental, infectious, or psychosocial factors—while not causing Tourette's—can influence its severity.
Autoimmune processes may affect tic onset and exacerbation in some cases. The unproven and contentious hypothesis that Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections (PANDAS) plays a role in the onset of tic disorders and OCD is a current focus of research.
The exact mechanism affecting the inherited vulnerability to Tourette's has not been established, and the precise etiology is unknown. Tics are believed to result from dysfunction in cortical and subcortical regions, the thalamus, basal ganglia and frontal cortex., Neuroanatomic models implicate failures in circuits connecting the brain's cortex and subcortex, and imaging techniques implicate the basal ganglia and frontal cortex.
Some forms of OCD may be genetically linked to Tourette's. A subset of OCD is thought to be etiologically related to Tourette's and may be a different expression of the same factors that are important for the expression of tics. The genetic relationship of ADHD to Tourette syndrome, however, has not been fully established.
4-clinical picture:
The tics associated with Tourette's constantly change in number, frequency, severity and anatomical location. Waxing and waning—the ongoing increase and decrease in severity and frequency of tics—occurs differently in each individual. Tics also occur in "bouts of bouts", which vary for each person.
Tics are described as semi-voluntary or "unvoluntary", because they are not strictly involuntary—they may be experienced as a voluntary response to the unwanted, premonitory urge. A unique aspect of tics, relative to other movement disorders, is that they are suppressible yet irresistible; they are experienced as an irresistible urge that must eventually be expressed. People with Tourette's are sometimes able to suppress their tics to some extent for limited periods of time, but doing so often results in an explosion of tics afterward. People with Tourette's may seek a secluded spot to release their symptoms, or there may be a marked increase in tics, after a period of suppression at school or at work.
In contrast to the stereotyped movements of other movement disorders (e.g. choreas, dystonias, myoclonus, and dyskinesias), the tics of Tourette's are temporarily suppressible and preceded by a premonitory urge. Immediately preceding tic onset, most individuals with Tourette's are aware of an urge that is similar to the need to sneeze or scratch an itch. Individuals describe the need to tic as a build up of tension which they consciously choose to release, as if they "had to do it”. Examples of the premonitory urge are the feeling of having something in one's throat, or a localized discomfort in the shoulders, leading to the need to clear one's throat or shrug the shoulders. The actual tic may be felt as relieving this tension or sensation, similar to scratching an itch. Another example is blinking to relieve an uncomfortable sensation in the eye. These urges and sensations, preceding the expression of the movement or vocalization as a tic, are referred to as "premonitory sensory phenomena". Published descriptions of the tics of Tourette's identify sensory phenomena as the core symptom of the syndrome, even though they are not included in the diagnostic criteria.
*TS is recognized as a disorder with childhood onset. Although symptoms can begin during infancy or in late adolescence, the usual age of onset of tics has been found to occur in patients aged 2-15 years, with a mean age range of 6-7 years. Approximately 75% of patients with TS have symptoms by age 11 years.
*Tics may present suddenly; however, they usually become noticeable gradually or have intervening spontaneous remissions.
*In most patients, simple tics (eg, blinking, nose twitching) are the presenting symptoms. A review of several large studies, composed of approximately 2400 patients, indicates that 50-70% of patients with TS reported facial tics as their initial symptom.
• Other simple tics, involving mostly neck or shoulder movements, are the next most common presenting symptoms, followed by involuntary movements of the upper extremities.
• Tics of the lower extremities and trunk are the least common.
• Vocal tics occur as initial symptoms in only 12-37% of patients with TS. they may change from meaningless sounds to words or phrases. Coprolalia, the most complex type of vocal tic, usually does not appear until 4-7 years after the onset of the disorder; however, coprolalia only occurs in less than one third of patients with TS.
Other symptoms may appear as the syndrome develops to its fullest severity, to include the following:
• Slower more sustained movements (eg, dystonic tics)
• Self-injurious tics
• Sensory tics
• Copropraxia (the involuntary making of obscene gestures.)
• Echolalia (the repetition of phrases, or mimicking of gestures)
• Palilalia (the repetition of a word rapidly and involuntarily )
• Irregular speech intonations
• Talking with different accents
6-What exacerbate the tics ?
this may occur in response to identifiable physical or emotional stresses, however, this response varies from patient to patient. as follows:
*Exogenous agents (eg, caffeine, certain medications) may cause symptom exacerbation
*Endogenous processes (eg, menstrual cycles, other hormonal changes) also may alter the severity of symptoms.
*Excitement, positive or negative in nature, causes a worsening of tics.
*Tics also may increase during relaxation after a period of stress. In contrast to other hyperkinetic movement disorders that usually are suppressed completely during sleep, motor and phonic tics may persist during all stages of sleep.
*Many patients note a reduction in their tics when distracted by concentrating on mental or physical tasks (eg, playing a video game, during an orgasm). Others have increased frequency and intensity of their tics when distracted, especially when they no longer have the need to suppress the tics. Tics also typically are exacerbated by dopaminergic drugs and CNS stimulants, including methylphenidate and cocaine.
7-Clinical Classification of tics :
1-Simple motor tics: These are isolated, involving only one group of muscles, and may be single or repetitive.
-Clonic - Brief (usually <100 m/s), jerklike (eg, blinking, nose twitching, head jerking)
-Dystonic - Sustained (usually >300 m/s), twisting, or squeezing movement or posture (eg, blepharospasm, oculogyric movements, bruxism, mouth opening, torticollis, shoulder rotation)
-Tonic - Sustained (usually >500 m/s), isometric contraction (eg, abdominal or limb tensing)
2-Complex motor tics: These are coordinated, sequential movements that may resemble normal motor acts or gestures but are inappropriately intense and timed and may be repetitive (stereotypic).
-Seemingly nonpurposeful (eg, head shaking, trunk bending)
-Seemingly purposeful - May be difficult to differentiate from compulsions (eg, touching, throwing, hitting, jumping, kicking), copropraxia (obscene gestures), echopraxia (imitating the gestures of others)
3-Simple phonic tics: These tics are single meaningless sounds and noises (eg, throat clearing, grunting, sniffing, squeaking, coughing, barking, screaming, whistling, blowing, sucking).
4-Complex phonic tics: These tics are linguistically meaningful utterances and verbalizations (eg, coprolalia, echolalia, palilalia (involuntary repetition of words or phrases).
5-Compulsive tics: These tics are movements or sounds that occur in response to an inner urge or feeling.
• Classification of TS:
1-Pure TS - Consists only of motor and vocal tics
2-Full-blown TS - Also includes coprophenomena, echophenomena, and paliphenomena
3-TS plus syndromes - When a patient also has ADHD, OCBs, or OCD
8-what is the Differential diagnosis:
*Transient tic disorder of childhood: As described earlier, this syndrome is similar to TS, but it lasts for less than a year.
*Chronic multiple tic disorder: This has a great similarity to TS but remains present in adulthood.
*Chronic single tic disorder: It is a motor or vocal tic in adulthood.
9-How to Diagnose TS ?
*Tics that appear early in the course of the condition are frequently confused with other conditions, such as allergies, asthma, and vision problems: pediatricians, allergists and ophthalmologists are typically the first to see a child with tics.
*TS is a clinical diagnosis; therefore, no specific laboratory or genetic tests exist to help establish the diagnosis.
Diagnostic Criteria:
• Both multiple motor and one or more vocal tics have been present at some time during the illness, although not necessarily at the same time.
• Tics occur many times a day, nearly every day or intermittently, throughout a period of more than 1 year. During this period there must not be a tic-free period of more than 3 consecutive months.
• Onset is before 18 years of age.
• The disturbance causes marked distress or significant impairment in social, occupational, or other important areas of functioning.
• The disturbance is not due to the direct physiologic effects of a substance or a general medical condition.
10-how to Treat ?
1-Patient education: Ideally, patients with mild tics who have made a good adaptation in their lives can avoid the use of medications. Educating patients, family members, peers, and school personnel regarding the nature of TS; restructuring the school environment; and providing supportive counseling are measures that may be sufficient to avoid pharmacotherapy and avoid their side effects that would be worse than the symptoms.
2- Medication therapy: This therapy should be considered if tics are functionally disabling and/or are not remediable to nonpharmacologic interventions.
Classes of medication used in the treatment of patients with TS include neuroleptics, nonneuroleptic dopamine antagonists, and immune modulators.
*e.g risperidone, ziprasidone ,haloperidol ,pimozide ,
*The antihypertensive agents clonidine and guanfacine are also used to treat tics; studies show variable efficacy, but a lower side effect profile than the neuroleptics. *Stimulants and other medications may be useful in treating ADHD when it co-occurs with tic disorders.
* Drugs from several other classes of medications can be used when stimulant trials fail, including guanfacine ,atomoxetine and tricyclics. Clomipramine ,a tricyclic antidepressant, and SSRIs—a class of antidepressants including fluoxetine (Prozac), sertraline , and fluvoxamine may be prescribed when a Tourette's patient also has symptoms of obsessive–compulsive disorder.
• Psychotherapeutic techniques: Various psychotherapeutic techniques, including assertiveness training, cognitive therapy, and self-monitoring, have been tried in the treatment of patients with TS. They mainly are used in the treatment of patients with TS associated with OCD or OCBs.
• Future therapy: The following methods have been tried on very few patients with TS in clinical trials, with reported improvement in the tics:
o Hormonal therapy (antiestrogenic agent, clomiphene)
o Laser therapy
o Acupuncture
o Psychosurgery
3-Surgical Care: Surgical approaches for TS have been attempted in patients who are severely disabled who have inadequate responses to other therapies.
• Patients who were treated typically exhibited a complicated clinical picture, usually with severe tics combined with disabling obsessive-compulsive and ritualistic behaviors.
• Surgical approaches that have been described include bimedial frontal leukotomy, bilateral anterior cingulotomy, bilateral limbic leukotomy, and coagulation of dorsomedian and intermediate lateral thalamic nuclei. Benefits of such surgical treatment are described in individual cases, but a surgical approach must be considered a last resort for patients who are severely disabled.
Consultations: Treatment of patients with TS should be a collaborative event among the neurologist, psychiatrist or psychologist, family members, and school professionals.
References:
http://www.emedicine.com/med/topic3107.htm
http://en.wikipedia.org/wiki/Tourette_syndrome
http://www.nlm.nih.gov/medlineplus/ency/article/000733.htm#Definition
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