Tics and Tourette syndrome: Viva

Opening question

Examiner: Walk me through how you confirm the diagnosis in this boy.

Candidate: This boy has Tourette disorder by DSM-5 criteria. He has multiple motor tics, the eye-blinking, facial grimacing, and shoulder-shrugging, plus at least one vocal tic, the throat-clearing, present for over one year, with onset before age 18, and no substance or medical cause. Motor and vocal tics need not occur at the same moment, and coprolalia is not required. The diagnosis is entirely clinical, built on the history and on home video, and the family history of paternal childhood tics supports it given the high heritability. [2]

Probing the phenomenology

Examiner: How do you know these are tics and not stereotypies or another movement disorder?

Candidate: The defining phenomenology is the premonitory urge, the mounting tension relieved only by the movement, the brief suppressibility with rebound, and the waxing-and-waning, body-shifting course. A stereotypy is rhythmic, fixed, and purposeful-appearing and lacks the urge and suppressibility, classically seen in a younger child or a child with autism. Myoclonus is a brief shock-like jerk without urge, chorea is flowing and non-suppressible, and dystonia is sustained posturing. His school restlessness is the motor overactivity of comorbid attention-deficit or hyperactivity disorder, a separate phenomenon from his discrete tics, and I would distinguish the two using home video. [2] [6]

Escalation: management

Examiner: He is distressed and being teased. How do you manage him?

Candidate: I take a stepped approach aimed at function, not tic elimination. First I provide psychoeducation and reassurance and secure school accommodation. Because his tics cause impairment, the first active treatment is Comprehensive Behavioural Intervention for Tics, or CBIT, a behavioural therapy built on habit reversal training. The Piacentini randomised trial showed CBIT significantly reduces tic severity compared with supportive therapy, and the American Academy of Neurology and European guidelines endorse it as first-line. [1] [2]

Examiner: And if behavioural therapy is not enough?

Candidate: I move to pharmacotherapy. The preferred first drugs are the alpha-2 agonists clonidine or guanfacine, chosen first because they also treat his attention-deficit or hyperactivity disorder and have a safer profile than antipsychotics, with blood-pressure monitoring. The antipsychotics risperidone and aripiprazole are the strongest tic suppressants and are reserved for moderate to severe impairment, started low and titrated with weight, metabolic, and extrapyramidal monitoring. I would not use an antipsychotic for mild tics that needed only reassurance. [2] [5]

Escalation: the comorbidities

Examiner: His attention-deficit or hyperactivity disorder is failing him at school. Would a stimulant worsen his tics?

Candidate: The long-standing concern that stimulants worsen tics has been largely refuted by the modern evidence, which shows stimulants do not routinely exacerbate tics in Tourette disorder. His attention-deficit or hyperactivity disorder is the dominant source of impairment, so I would treat it with behavioural strategies and, if needed, with stimulant or non-stimulant medication, and I would not withhold effective treatment on tic grounds. His obsessive-compulsive checking rituals are treated with cognitive behavioural therapy using exposure and response prevention, with a selective serotonin reuptake inhibitor for moderate to severe obsessive-compulsive disorder. The comorbidities usually cause more impairment than the tics, so they drive the plan. [6]

Escalation: prognosis

Examiner: What do you tell his family about the future?

Candidate: The prognosis for the tics is favourable. Tic severity peaks around 10 to 12 years and improves substantially for most children through late adolescence, with only a minority carrying severe tics into adulthood. I would add one nuance, that obsessive-compulsive symptoms can persist or rise even as the tics fade, which is why I follow the comorbidities over time. I would counsel the family that treatment aims at function, that tics fluctuate, that a bad week is not deterioration, and that the long-term outlook is good. [11]

The corner question

Examiner: If instead of this gradual onset his tics and obsessive-compulsive symptoms had exploded over 48 hours after a streptococcal sore throat, what would change?

Candidate: That abrupt, dramatic onset of tics and obsessive-compulsive symptoms after infection is paediatric acute-onset neuropsychiatric syndrome, or PANS, and its post-streptococcal subtype PANDAS. It is distinct from the gradual waxing-and-waning onset of classic Tourette. I would involve paediatric neurology and psychiatry, treat the obsessive-compulsive and tic symptoms with behavioural and pharmacological means, and evaluate and treat any ongoing infection. The role of immune-modulating treatments such as antibiotics, intravenous immunoglobulin, and plasma exchange is debated and is reserved for specialist centres. [2]