Tourette syndrome

Tourette syndrome (TS or simply Tourette's) is a common neurodevelopmental disorder with onset in childhood, characterized by multiple motor tics and at least one vocal (phonic) tic. These tics characteristically wax and wane, can be suppressed temporarily, and are typically preceded by an unwanted urge or sensation in the affected muscles. Some common tics are eye blinking, coughing, throat clearing, sniffing, and facial movements. Tourette's does not adversely affect intelligence or life expectancy. Tourette's is defined as part of a spectrum of tic disorders, which includes provisional, transient and persistent (chronic) tics. Tics are often unnoticed by casual observers. While the exact cause is unknown, it is believed to involve a combination of genetic and environmental factors. There are no specific tests for diagnosing Tourette's; it is not always correctly identified because most cases are mild and the severity of tics decreases for most children as they pass through adolescence. Extreme Tourette's in adulthood, though sensationalized in the media, is a rarity. In most cases, medication for tics is not necessary. Education is an important part of any treatment plan, and explanation and reassurance alone are often sufficient treatment. Many individuals with Tourette's go undiagnosed or never seek medical care. Among those who are seen in specialty clinics, attention-deficit hyperactivity disorder (ADHD) and obsessive–compulsive disorder (OCD) are present at higher rates. These co-occurring diagnoses often cause more impairment to the individual than the tics; hence, it is important to correctly identify associated conditions and treat them. About 1% of school-age children and adolescents have Tourette's. It was once considered a rare and bizarre syndrome, most often associated with coprolalia (the utterance of obscene words or socially inappropriate and derogatory remarks), but this symptom is present in only a small minority of people with Tourette's. The condition was named by Jean-Martin Charcot (1825–1893) on behalf of his resident, Georges Albert Édouard Brutus Gilles de la Tourette (1857–1904), a French physician and neurologist, who published an account of nine patients with Tourette's in 1885. Tics are sudden, repetitive, nonrhythmic movements (motor tics) and utterances (phonic tics) that involve discrete muscle groups. Joseph Jankovic describes vocal or phonic tics as 'motor tics that involve respiratory, laryngeal, pharyngeal, oral, and nasal musculature'. Tourette's was classified by the fourth version of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) as one of several tic disorders 'usually first diagnosed in infancy, childhood, or adolescence' according to type (motor or phonic tics) and duration (transient or chronic). Transient tic disorders consisted of multiple motor tics, phonic tics or both, with a duration between four weeks and twelve months. Chronic tic disorder was either single or multiple, motor or phonic tics (but not both), which were present for more than a year. Tourette's was diagnosed when multiple motor tics, and at least one phonic tic, are present for more than a year. The fifth version of the DSM (DSM-5), published in May 2013, reclassified Tourette's and tic disorders as motor disorders listed in the neurodevelopmental disorder category, and replaced transient tic disorder with provisional tic disorder, but made few other significant changes. Tic disorders are defined only slightly differently by the World Health Organization International Statistical Classification of Diseases and Related Health Problems, ICD-10; code F95.2 is for combined vocal and multiple motor tic disorder . Although Tourette's is the more severe expression of the spectrum of tic disorders, most cases are mild and many individuals with TS do not come to clinical attention. The severity of symptoms varies widely among people with Tourette's, and mild cases may be undetected. Tics are movements or sounds 'that occur intermittently and unpredictably out of a background of normal motor activity', having the appearance of 'normal behaviors gone wrong'. The tics associated with Tourette's 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 may also occur in 'bouts of bouts', which vary for each person.