Tourette Syndrome And Other Tic Disorders
Definitions of Tic Disorders
Associated Behaviors and Cognitive Difficulties
Epidemiology and Genetics
Clinical Assessment Of Tourette Syndrome
Treatment Of Tourette Syndrome
Pharmacological Treatment of Tourette Syndrome
Academic and Occupational Interventions
Today the full-blown case of TS is unlikely to be confused with any other disorder. However, only a decade ago TS was frequently misdiagnosed as schizophrenia, obsessive-compulsive disorder, Sydenham's chorea, epilepsy, or nervous habits. The differentiation of TS from other tic syndromes may be no more than semantic, especially since recent genetic evidence links TS with multiple tics. Transient tics of childhood are best defined in retrospect. At times it may be difficult to distinguish children with extreme attention deficit hyperactivity disorder (ADHD) from TS. Many ADHD children, on close examination, have a few phonic or motor tics, grimace, or produce noises similar to those of TS. Since at least half of the TS patients also have attention deficits and hyperactivity as children, a physician may well be confused. However, the treating doctor should be aware of the potential dangers of treating a possible case of TS with stimulant medication. On rare occasions the differentiation between TS and a seizure disorder may be problematic. The symptoms of TS sometimes occur in a rather sharply separated paroxysmal manner and may resemble automatisms. TS patients, however, retain a clear consciousness during such paroxysms. If the diagnosis is in doubt, an EEG may be useful. We have seen TS in association with a number of developmental and other neurological disorders.
It is possible that central nervous system injury from trauma or disease may cause a child to be vulnerable to the expression of the disorder, particularly if there is a genetic predisposition. Autistic and retarded children may display the entire gamut of TS symptoms, but whether an autistic or retarded individual requires the additional diagnosis of TS may remain an open question until there is a biological or other diagnostic test specifically for TS. In older patients, conditions such as Wilson's disease, tardive dyskinesia, Meige's syndrome, chronic amphetamine abuse, and the stereotypic movements of schizophrenia must be considered in the differential diagnosis. The distinction can usually be made by taking a good history or by blood tests. Since more physicians are now aware of TS, there is a growing danger of overdiagnosis or over-treatment. Prevailing diagnostic criteria would require that all children with suppressible multiple motor and phonic tics, however minimal, of at least one year, should be diagnosed as having TS. It is up to the clinician to consider the effect that the symptoms have on the patient's ability to function as well as the severity of associated symptoms before deciding to treat with medication.
TABLE 1. RANGE OF SYMPTOMS OF TS
Simple motor tics: fast, darting, and meaningless.
Complex motor tics: slower, may appear purposeful
Simple vocal tics: meaningless sounds and noises.
Complex vocal tics: linguistically meaningful utterances such as words and phrases (including coprolalia, echolalia, and palilalia).
Behavioral and Developmental
Attention deficit hyperactivity disorder, obsessions and compulsions, emotional problems, irritability, impulsivity, aggressivity, and self-injurious behaviors; various learning disabilities
The varied symptoms of TS can be divided into motor, vocal, and behavioral manifestations (Table 2). Complex motor tics can be virtually any type of movement that the body can produce including gyrating, hopping, clapping, tensing arm or neck muscles, touching people or things, and obscene gesturing. At some point in the continuum of complex motor tics, the term "compulsion" seems appropriate for capturing the organized, ritualistic character of the actions. The need to do and then redo or undo the same action a certain number of times (e.g., to stretch out an arm ten times
Definitions of Tic Disorders
Tics are involuntary, rapid, repetitive, and stereotyped movements of individual muscle groups. They are more easily recognized than precisely defined. Disorders involving tics generally are divided into categories according to age of onset, duration of symptoms, and the presence of vocal or phonic tics in addition to motor tics. Transient tic disorders often begin during the early school years and can occur in up to 15% of all children. Common tics include eye blinking, nose puckering, grimacing, and squinting. Transient vocalizations are less common and include various throat sounds, humming, or other noises. Childhood tics may be bizarre, such as licking the palm or poking and pinching the genitals. Transient tics last only weeks or a few months and usually are not associated with specific behavioral or school problems. They are especially noticeable with heightened excitement or fatigue. As with all tic syndromes, boys are three to four times more often afflicted than g! irls. While transient tics by definition do not persist for more than a year, it is not uncommon for a child to have series of transient tics over the course of several years. Chronic tic disorders are differentiated from those that are transient not only by their duration over many years, but by their relatively unchanging character. While transient tics come and go - with sniffing replaced by forehead furrowing or finger snapping, chronic tics - such as contorting one side of the face or blinking - may persist unchanged for years. Chronic multiple tics suggest that an individual has several chronic motor tics. It is often not an easy task to draw the lines between transient tics, chronic tics, and chronic multiple tics. Tourette Syndrome (TS), first described by Gilles de la Tourette, can be the most debilitating tic disorder, and is characterized by multiform, frequently changing motor and phonic tics. The prevailing diagnostic criteria include onset before the age of 21; recurrent, involuntary, rapid, purposeless motor movements affecting multiple muscle groups; one or more vocal tics; variations in the intensity of the symptoms over weeks to months (waxing and waning); and a duration of more than one year. While the criteria appear basically valid, they are not absolute. First, there have been rare cases of TS which have emerged later than age 21. Second, the concept of "involuntary" may be hard to define operationally, since some patients experience their tics as having a volitional component - a capitulation to an internal urge for motor discharge accompanied by psychological tension aefore writing, to even up, or to stand up and push a chair into "just the right position") is compulsive in duality and accompanied by considerable internal discomfort. Complex motor tics may greatly impair school work, e.g., when a child must stab at a workbook with a pencil or must go over the same letter so many times that the paper is worn thin. Self-destructive behaviors, such as head banging, eye poking, andlip biting, also may occur. Vocal tics extend over a similar spectrum of complexity and disruption as motor tics ( The most socially distressing complex vocal symptom is coprolalia, the explosive utterance of foul or "dirty" words or more elaborate sexual and aggressive statements. While coprolalia occurs in only a minority of TS patients (from 5-40%, depending on the clinical series), it remains the most well known symptom of TS. It should be emphasized that a diagnosis of TS does not require that coprolalia is present. Some TS patients may have a tendency to imitate what they have just seen (echopraxia), heard (echolalia), or said (palilalia). For example, the patient may feel an impulse to imitate another's body movements, to speak with an odd inflection, or to accent a syllable just the way it has been pronounced by another person. Such modeling or repetition may lead to the onset of new specific symptoms that will wax and wane in the same way as other TS symptoms.
TABLE 2. EXAMPLES OF MOTOR SYMPTOMS
Simple motor tics
Eye blinking, grimacing, nose twitching, lip pouting, shoulder shrugging, arm jerking, abdominal tensing, kicking, finger movements, jaw snapping, tooth clicking, frowning, tensing parts of the body, and rapid jerking of any part of the body.
Complex motor tics
Hopping, clapping, touching objects (or others or self), throwing, arranging, gyrating, bending, "dystonic" postures, biting the mouth, the lip, or the arm, headbanging, arm thrusting, striking out, picking scabs, writhing movements, rolling eyes upwards or side-to-side, making funny expressions, sticking out the tongue, kissing, pinching, writing over-and-over the same letter or word, pulling back on a pencil while writing, and tearing paper or books.
"Giving the finger" and other obscene gestures.
Imitating gestures or movements of other people.
TABLE 3. EXAMPLES OF VOCAL SYMPTOMS
Simple vocal tics
Coughing, spitting, screeching, barking, grunting, gurgling, clacking, whistling, hissing, sucking sounds, and syllable sounds such as "uh, uh," "eee," and "bu."
Complex vocal tics
"Oh boy," "you know," "shut up," "you're fat," "all right," and "what's that." or any other understandable word or phrase
Repeating a phrase until it sounds "just right" and saying something over 3 times.
Unusual rhythms, tone, accents, loudness, and very rapid speech.
Obscene, aggressive, or otherwise socially unacceptable words or phrases.
Repeating one's own words or parts of words.
Repeating sounds, words, or parts of words of others.
The symptoms of TS can be characterized as mild, moderate, or severe by their frequency, their complexity, and the degree to which they cause impairment or disruption of the patient's ongoingctivities and daily life. For example, extremely frequent tics that occur 20-30 times a minute, such as blinking, nodding, or arm flexion, may be less disruptive than an infrequent tic that occurs several times an hour, such as loud barking, coprolalic utterances, or touching tics. There may be tremendous variability over short and long periods of time in symptomatology, frequency, and severity. Patients may be able to inhibit or not feel a great need to emit their symptoms while at school or work. When they arrive home, however, the tics may erupt with violence and remain at a distressing level throughout the remainder of the day. It is not unusual for patients to "lose" their tics as they enter the doctor's office. Parents may plead with a child to "show the doctor what you do at home," only to be told that the youngster "just doesn't feel like doing them" or "can't do them" on command. Adults will say "I only wish you could see me outside of your office," and family members will heartily agree. A patient with minimal symptoms may display more usual severe tics when the examination is over. Thus, for example, the doctor often sees a nearly symptom-free patient leave the office who begins to hop, flail, or bark as soon as the street or even the bathroom is reached. In addition to the moment-to-moment or short-term changes in symptom intensity, many patients have oscillations in severity over the course of weeks and months. The waxing and waning of severity may be triggered by changes in the patient's life; for example, around the time of holidays, children may develop exacerbations that take weeks to subside. Other patients report that their symptoms show seasonal fluctuation. However, there are no rigorous data on whether life events, stresses, or seasons, in fact, do influence the onset or offset of a period of exacerbation. Once a patient enters a phase of waxing symptomatology, a process seems to be triggered that will run its course - usually within 1-3 months. In its most severe forms, patients may have uncountable motor and vocal tics during all their waking hours with paroxysms of full-body movements, shouting, or self-mutilation. Despite that, many patients with severe tics achieve adequate social adjustment in adult life, although usually with considerable emotional pain. The factors that appear to be of importance with regard to social adaptation include the seriousness of attentional problems, intelligence, the degree of family acceptance and support, and ego strength more than the severity of motor and vocal tics. In adolescence and early adulthood, TS patients frequently come to feel that their social isolation, vocational and academic failure, and painful and disfiguring symptoms are more than they can bear. At times, a small number may consider and attempt suicide. Conversely, some patients with the most bizarre and disruptive symptomatology may achieve excellent social, academic, and vocational adjustments.
Associated Behaviors and Cognitive Difficulties
As well as tics, there are a variety of behavioral and psychological difficulties that are experienced by many, though not all, patients with TS. Those behavioral features have placed TS on the border between neurology and psychiatry, and require an understanding of both disciplines to comprehend the complex problems faced by many TS patients. The most frequently reported behavioral problems are attentional deficits, obsessions, compulsions, impulsivity, irritability, aggressivity, immaturity, self-injurious behaviors, and depression. Some of the behaviors (e.g., obsessive compulsive behavior) may be an integral part of TS, while others may be more common in TS patients because of certain biological vulnerabilities (e.g., ADHD). Still others may represent responses to the social stresses associated with a multiple tic disorder or a combination of biological and psychological reactions.
Obsessions and Compulsions
Although TS may present itself purely as a disorder of multiple motor and vocal tics, many TS patients also have obsessive-compulsive (OC) symptoms that may be as disruptive to their lives as the tics - sometimes even more so. There is recent evidence that obsessive-compulsive symptomatology may actually be another expression of the TS gene and, therefore, an integral part of the disorder. Whether this is true or not, it has been well documented that a high percentage of TS patients have OC symptoms, that those symptoms tend to appear somewhat later than the tics, and that they may be seriously impairing. The nature of OC symptoms in TS patients is quite variable. Conventionally, obsessions are defined as thoughts, images, or impulses that intrude on consciousness, are involuntary and distressful, and while perceived as silly or excessive, cannot be abolished. Compulsions consist of the actual behaviors carried out in response to the obsessions or in an effort to ward them off. Typical OC behaviors include rituals of counting, checking things over and over, and washing or cleaning excessively. While many TS patients do have such behaviors, there are other symptoms typical of TS patients that seem to straddle the border between tics and OC symptoms. Examples are the need to "even things up," to touch things a certain number of times, to perform tasks over and over until they "feel right," as well as self-injurious behaviors.
Attention Deficit Hyperactivity Disorder (ADHD)