TS is a complex neuro-developmental disorder with a strong but poorly understood heritability (autosomal dominant - possibly with incomplete penetrance). It usually becomes apparant between the ages of 4 and 18 but usually closer to the younger limit. Some children exhibit signs later but it is usual to expect it to become apparant by adulthood. There are no signs that can be elicited reliably on examination. Referral to an approved specialist neurologist or appropriate neuro-psychiatrist or developmental paediatrician is advised as early as possible. Lists of approved physicians are available from most National Tourette Syndrome Associations in the developed world.
It is extremely common for General/Family Practitioners not to have experienced a case of Tourette Syndrome even over a lengthy career. Part of this is undoubtedly due to an hitherto poor diagnostic rate or missed/mis-diagnoses. Although the diversity of presentation can appear complex, it is in reality relatively straightforward to diagnose. Remember 90% of 'diagnosis' is in the patient history. Do not be overly dependant on observable signs as you may not detect any. There is little to be seen during general or neurological examination unless visible motor tics are present or vocal tics are prominent. Remember many children (and more so adults) with TS are able to suppress tics and they may not be seen during the consultation. Listen carefully to the child, adult or parent/s. It is relatively unlikely that the symptoms of TS would be purposely and consistently 'faked' by a child or falsely reported by a parent in order to seek a diagnosis of Tourette Syndrome. Few people have an accurate picture of the symptomatology of the disorder and would tend to conform to the media-driven misconceptions of the symptoms in attempting to falsely present with the condition. It should also be considered that TS is not the most desireable of diagnoses in respect of the current 'stigmatising' nature of the condition. It is most likely that a parent will be driven to seek a medical opinion due to the impact on family life, bullying at school and from peers or as a result of 'difficulties' in the classroom. For many, a diagnosis may be essential in order to 'qualify' for educational provision and to improve school/college opportunities and progress.
TS is not a 'mental illness' and does not have a psychological aetiology. The standard 'Mental State Examination' will reveal little of relevance. Neurological examination will also reveal little although during close examination of the limbs, face and eyes it may be possible to detect muscular tics. Swelling/inflammation or arthralgia in joints subjected to repetitive tics may occur e.g. fingers/wrist/neck etc. Some motor tics may be unintentionally or un-intentionally self-injurious and result in visible bruising or lacerations. Motor tics tend to occur first in the cephalic region (facial tics/grimaces, eye rolling, blinking, eye brow raising, screwing-up/twitching of nose, head nodding, neck twisting/tensing). There is a tendency for a head-to-toe progression in motor tics with time. Motor tics can be numerous but 'not seen' and may consist of muscles tensing and relaxing e.g. in the abdomen, diaphragm, buttocks, leg, arm, shoulder and neck muscles. Some individuals may have tics that render walking difficult and include complex tics such as twirling/turning or touching the ground, touching a foot, pulling up a sock, jumping, kicking the buttocks etc. which considerably slow their progress.
Vocal tics may be overt and obvious. Often 'throat clearing' appears early but tics may consist of words, phrases, socially or situationally inappropriate phrases, squeaks, squeals, tongue-clicks, lip-smacking, blowing-raspberries, guttural sounds from the back of the throat, barks, yelps etc. Some individuals may use swear words (coprolalia) but this is relatively rare (around 10% or less of cases). Other vocal tics may be more subtle and missed such as: blowing air forcibly or rapidly through the nose or mouth with accompanying diaphragmatic contractions. The diversity of vocal tics can encompass the entire range of possible sounds available to the human voice. Despite many doctors believing otherwise, coprolalia (cursing) is rare and is NOT a diagnostic requirement. Other coprophenomena (again relatively rare) may occur, such as copropraxia in which socially-unacceptable gestures etc. may occur (e.g. giving-the-finger).
The obstetric, developmental and educational component of the paediatric history are useful for assessing any delay or advancement in normal child development. Children with TS do, according to their parents, show earlier signs of TS when retrospectively viewed after subsequent diagnosis. In an educational setting NLD (non-verbal learning difficulties may be apparent). There may be a family history of tic disorders, OCD/OCB, attention deficit and poor educational development/exclusion or undiagnosed TS.
Classically the diagnosis is recorded as a transient tic disorder until one year has passed with both motor and some vocal tics before determining that it is TS.
It is essential with children in whom a diagnosis of Tourette Syndrome is suspected or established, that a thorough evaluation is carried out to determine what provision and adjustments may be necessary at school/college in order to reduce any disadvantage due to impairments caused by TS or related co-occurring disorders. Ideally this will involve a qualified educational/clinical psychologist who has sufficient understanding of TS. Early interventions in educational provision are highly beneficial and may help reduce the impact of learning difficulties and reduce the likelihood of psychological consequences that may result from an unsuitable educational environment.
Beware of mis-diagnosis (differentials in TS). Common pitfalls to correct diagnosis are often due to obtaining an incomplete history. TS is complex and many symptoms mimic those of psychiatric conditions and behavioural disorders as well as other developmental disorders. People with TS are often very physically and mentally active and driven and flit from one subject to another rapidly, or may perseverate in obsessive detail on one subject. They can often speak very rapidly and voluminously and show impatience when listening to others speak and tend to jump in 'out of turn.' It is easy to assume you are dealing with ADD, ADHD or ASD although these must not be excluded and may be co-ocurring conditions with TS. Patients with TS often sleep poorly, wake frequently, have unwanted and troublesome thoughts and may suffer from low-mood. All can be suggestive of a affective or mood disorder (e.g. uni-polar depression/bi-polar disorder). Evidence suggests that in TS, CNS serotonin (and nor-adrenaline) levels are low which may increase the risk of experiencing low-mood. Although experiencing low mood an individual may still be driven by their TS and appear relatively animated and bouyant. Low-mood may however also be a reactive consequence of the adversity experienced through living with TS.
Sensory processing issues are also a common aspect of TS (see also under NLD). There may be sensory hypersensitivity (with consequent sensory defensiveness) or low-latent inhibition where the individual may be 'overwhelmed' by sensory detail. Attention should be paid to the possibility of sensory processing problems that interfere with the comprehension of speech and visual input and so affect educational potential. A hearing test may be advisable.
Some patients with TS may experience polyuria and require frequent toilet breaks. The mechanism for this is not yet fully elucidated but appears to be a consequence of impaired neuro-hormonal regulation of diuresis. In this respect it mimics diabetes insipidus. Beware of diagnosing polydipsia as a psychological cause of polyuria. Polyuria in this case leads to compensatory polydipsia. Reducing fluid intake appears to have a very delayed response with regard to increasing water-reabsorption and reducing urine-flow and requires relatively prolonged dehydration.
Evidence suggests dopamine is the key neurotransmitter responsible for tic behaviours and that it is predominantly over-activity of dopaminergic neurons in the basal ganglia that are implicated. The involvement of the serotinergic system is also implicated in tic behaviours and many other TS symptoms and behaviours.
Perhaps the biggest challenge and a subject of controversy are the very common obsessive and compulsive behaviours that are frequently part of TS. Psychiatric opinion has generally tended to see TS as merely a tic disorder and any other aspect as separate co-morbid disorders. There is hence something of a tradition for labelling such behaviours as co-morbid OCD. Recent studies suggest however that the obsessive-compulsive behaviours (OCB) of TS differ significantly from the pattern usually seen in classic OCD a perspective also supported by many patients with TS. In OCD there tend to be many behaviours that relate to 'worries' about cleanliness, 'germs' and contamination. In TS the pattern is often very complex and frequently includes many obsessions that relate to evening things up, balancing things and symmetry. There is also a subtle interplay involving complex-tics which are undoubtedly compulsive. The individual is aware of the seeming illogicality of obsessive thoughts that compel them to enact complex actions or rituals. These can be internalised and occur entirely within the mind and include mental recitation of words, phrases or counting rituals and reading-related difficulties, or overt and include touching, touching objects a certain number of times, rotating one way or the other etc. There is a growing tendency for these behaviours in TS to be referred to as OCB to distinguish them from OCD. Additionally there is a difference in the responsiveness of 'Tourettic OCD' behaviours and 'classic OCD' to medication (such as SSRIs). In TS these behaviours are often quite refractory to medication.
However many TS patients do report a significant benefit from SSRIs which varies from one individual to the next - they may feel calmer, have improved concentration, sleep better and experience reduced complex- tics but this has not been subject to methodical study. This may be an option for patients unwilling to accept neuroleptics or form an adjunct to other tic-reduction therapies such as clonidine etc. Paroxetine is contraindicated for paediatric use however fluoxetine or an alternative SSRI may be considered. It should be noted that many patients experience a very limited improvement in TS-related obsessive-compulsive behaviours with SSRI treatment when compared with patients being treated for 'classic' OCD. There are often marked differences in the symptomatology/presentation of Tourettic-OCB and OCD with a greater emphasis on symmetry and numerical obsessions than on concerns with 'germs', contamination and cleansing rituals as seen in OCD. SSRIs will also be of benefit if the patient suffers low-mood.
Neuroleptics (dopamine antagonists) should be used with caution in children and titrated to the lowest-effective dose. Dosages are considerably lower than those commonly used for the treatment of psychotic illness. Older typical antipsychotics such as haloperidol are still used in the treatment of TS and may be effective in some patients. Pimozide (Orap) is often effective but with a lower risk of adverse side-effects (e.g. Tardive dyskinesia etc.). Most prefer the non-neuroleptic, Clonidine as a first line treatment in children and consider the addition or substitution of a neuroleptic if necessary, if symptoms prove refractory. Seek advice and reference current pharmacy publications. The pharmacology of TS is ever-evolving and reference should always be made to the current literature before prescribing or referral made to an experienced specialist.
There is some controversy surrounding the use of methylphenidate (Ritalin) in patients with TS due to potential exacerbation of tics however recent published material suggests the benefits may be sufficient to make any side-effects acceptable. Hyperactivity and attention deficit are frequently intrinsic to TS and medication for the treatment of possible ADD/ADHD must be carefully considered.
Some individuals benefit from Cognitive behavioural and so-called 'habit-reversal' therapies (CBT/CBIT/HRT) which may be beneficial in reducing/ameliorating tic behaviours. Good advice to patients should always include strategies for reducing stress and anxiety and other symptom-provoking environmental triggers. Emotional reactiveness and negative reactions/distress due to sensory hypersensitivity/low latent inhibition can benefit from family and personal strategies to reduce the exposure to unnecessary stimuli. Always be aware that although noticeable vocal and motor tics may be distressing to the patient, it is often the unseen aspects of TS that cause the most difficulty e.g. obsessive thinking, unseen tics affecting attention, sensory discrimination, social communication, study, IT use, sleep and cognition. A very large proportion of children and adults with TS experience discrimination (they are generally painfully aware of even subtle aspects of this) on a daily basis and suffer profound disadvantage at many critical points in their life's progress e.g. social development and opportunities for long-term friendship, educational disadvantage and exclusion and to a very profound degree in career development. Although depression is common in TS, it is likely that adversity and continual negative encounters is the greater cause and that most depression experienced is 'reactive' rather than clinical only (e.g. for no reason). It may be that good support from others, such as TS support groups, the Tourette Syndrome Association and Tourette Camps and events, is the most beneficial approach to reducing the impact of depression. For some, CBT, may be very helpful although unlikely to be so unless the therapist is well-versed in TS. Frequently TS patients are angered by 'psychological' approaches that propose strategies that are appropriate to 'neurotypical' individuals which they feel are of little value for someone with TS. Their answer may often be "but you do not have Tourette syndrome" and "how do I manage my TS?" TS is extremely difficult to compensate for and many merely give the impression to others that they are doing well at it. The reality for many is that negotiating 'everyday life' may be challenging and exhausting but that others (even their closest companions) have little awareness of what they live through. Do not imagine that you know what TS is like to have. You will, invariably, be wrong. Take your cue from your patient and always let them try to describe it to you and listen carefully - you may be astonished and intrigued. Physicians who impress those with TS with their insight and understanding are very rare. There is a hunch among many with TS that when they meet someone who has unusually strong empathy and uncanny insight into their disorder, then it is quite likely that they too have TS (sometimes a strong rapport exists with those who have ASD/Asperger's or OCD also).
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