Tourette Syndrome — SAQ

Stem

An 8-year-old boy is brought by his parents with a 14-month history of recurrent tics. These began as eye-blinking and facial grimacing, then progressed over months to involve head-jerking and shoulder-shrugging, and over the last 4 months have included frequent throat-clearing, sniffing and occasional grunting. The tics come and go over weeks, are worse when he is anxious, excited or tired, and disappear during sleep. He can suppress them briefly at school (he describes a 'pressure building up' inside that is relieved only when he allows the tic to happen). He has never used obscene words or gestures. His teacher reports worsening inattention, fidgetiness and impulsivity, and he is falling behind in schoolwork. Neurological examination is normal. There is no family history of tics, but his maternal aunt has OCD.

Questions

a) What is the clinical diagnosis, and which FIVE DSM-5 criteria does this boy fulfil? (2 marks)

The diagnosis is Tourette syndrome (Tourette disorder). He fulfils all five DSM-5 criteria:^[1][8]

1. Multiple motor tics (eye-blinking, facial grimacing, head-jerking, shoulder-shrugging) plus one or more vocal (phonic) tics (throat-clearing, sniffing, grunting) — they need not be concurrent.
2. The tics are present during the illness, though not necessarily every day — he has them chronically but with waxing/waning.
3. Duration over 1 year (14 months) with no tic-free interval exceeding 3 months.
4. Onset before 18 years (began at about 6 to 7 years).
5. The disturbance is not attributable to the physiological effects of a substance (e.g. stimulants) or another medical condition (e.g. Huntington disease, post-streptococcal autoimmunity) — his neurological examination and history exclude these.

Note that coprolalia is NOT required for the diagnosis and is absent here (it affects only 8 to 15 percent of patients).^[8]

b) Outline the natural history of Tourette syndrome and the comorbidity you MUST screen for in this boy, with the rationale. (2 marks)

Natural history: the tics typically onset at 5 to 7 years (motor first, in the head and neck, then marching caudally over years), peak in severity at 10 to 12 years, and improve substantially in adolescence and early adulthood in about two-thirds of patients. Tics wax and wane, worsen with stress/anxiety/caffeine, and diminish during sleep and focused activity.^[1][8]

Mandatory comorbidity screen — ADHD and OCD (and anxiety/depression):

• ADHD — present in about 60 percent of patients and is the commonest and most functionally impairing comorbidity. This boy's teacher reports inattention, fidgetiness and impulsivity with academic decline — he clearly has comorbid ADHD, and it is the dominant source of impairment.
• OCD — present in 30 to 50 percent; his maternal aunt has OCD, consistent with the shared cortico-striato-thalamo-cortical-loop biology and the high heritability (50 to 70 percent).
• Also screen for anxiety, depression, sleep disturbance, learning difficulties and rage attacks.^[8]

The principle: the comorbidity drives most of the impairment — not the tics — so screening and treating it is central.^[2]

c) Describe the stepwise management you would offer this boy, naming the specific therapy, drug doses and routes, and the rationale for each step. (4 marks)

A stepwise, severity-driven approach (2022 European and 2019 AAN guidelines):^[2][3]

• Step 1 — Education, reassurance and school accommodations. Explain the neurobiology, the favourable natural history, and that most children with TS do NOT need medication. Provide school accommodations: time-outs for tics during class and examinations, a separate testing room, movement breaks, and a written education plan (IEP / 504 plan / EHCP). Signpost parent-support organisations.
• Step 2 — Comprehensive Behavioural Intervention for Tics (CBIT) / Habit Reversal Training (HRT), FIRST-LINE for impairing tics. CBIT comprises (i) awareness training (recognising the premonitory urge and the earliest sign of each tic), (ii) competing response training (an incompatible behaviour held for about 1 minute whenever the urge arises — e.g. slow rhythmic breathing instead of throat-clearing, or pushing the tongue against the palate), (iii) relaxation training, and (iv) contingency management / social support. The Piacentini et al. JAMA 2010 trial showed a 24.7 percent YGTSS reduction versus 7.6 percent with supportive therapy — comparable to medication, without side effects.
• Step 3 — Alpha-2 adrenergic agonist, FIRST-LINE drug (and treats the comorbid ADHD). Either clonidine 0.05 to 0.3 mg/day PO (start 0.05 mg at bedtime, titrate every 3 to 7 days; or a weekly transdermal patch) OR guanfacine extended-release 1 to 4 mg/day PO (start 1 mg, titrate weekly; better tolerated). Monitor blood pressure and heart rate; warn about sedation, dry mouth, hypotension and the risk of rebound hypertension on abrupt withdrawal.
• Step 4 — Antipsychotic, for severe tics refractory to behavioural therapy and alpha-2 agonist. Aripiprazole 2 to 20 mg/day PO (preferred first antipsychotic — partial D2 agonist, less weight gain and fewer EPSE than risperidone; main side effect akathisia) OR risperidone 0.25 to 3 mg/day PO. Baseline and periodic monitoring: weight, BMI, waist circumference, blood pressure, fasting glucose and lipids, ECG, prolactin, and EPSE / AIMS examination. Haloperidol is FDA-approved but rarely first-line (EPSE, NMS, tardive dyskinesia).
• Treat the comorbid ADHD first if it is the dominant impairment. Methylphenidate (immediate-release 5 to 20 mg twice daily or a long-acting formulation) does NOT significantly worsen tics (Tourette Syndrome Study Group 2002 trial); atomoxetine 0.5 to 1.2 mg/kg/day is a non-stimulant alternative. An alpha-2 agonist treats both ADHD and tics and is a sensible single drug.

d) Six months later the boy presents to the emergency department with continuous, violent neck-jerking and self-hitting tics for 18 hours; he is exhausted, dehydrated, has bitten his tongue and his serum creatine kinase is 8,000 U/L. Name the syndrome, the immediate management priorities, and one serious long-term medication-related complication you must counsel about if an antipsychotic is started. (2 marks)

This is malignant Tourette syndrome / status tic disorder — a medical emergency. Immediate management:^[1]

• Admit to a monitored bed (HDU/ICU if airway or cardiovascular compromise).
• IV sedation — an antipsychotic such as haloperidol 2 to 5 mg IV/IM and/or a benzodiazepine such as lorazepam 1 to 2 mg IV or midazolam.
• Intravenous fluids for dehydration and to protect the kidneys from rhabdomyolysis-induced acute kidney injury (CK is markedly raised at 8,000 U/L); monitor urine output, renal function and CK; consider alkalinisation of urine if severe.
• Protective measures — tongue guard, padding, eye protection.
• Inpatient multidisciplinary review (neurology, psychiatry, psychology) to plan a definitive longer-term regimen.

Serious long-term medication-related complication of an antipsychotic to counsel about: tardive dyskinesia — potentially irreversible involuntary choreo-athetoid movements (oro-facial and limb) that can emerge after months to years of D2-blocker exposure, and which is monitored at every visit with the Abnormal Involuntary Movement Scale (AIMS). (Other correct examples: metabolic syndrome, neuroleptic malignant syndrome, QT prolongation, akathisia, hyperprolactinaemia.)^[2]

References4ShowHide

1. [1]Johnson KA, Worbe Y, Foote KD. Tourette syndrome: clinical features, pathophysiology, and treatment. Lancet Neurology, 2023.PMID 36354027
2. [2]Müller-Vahl KR, Szejko N, Verdellen C, et al. European clinical guidelines for Tourette syndrome and other tic disorders: summary statement and recommendations. European Child and Adolescent Psychiatry, 2022.PMID 34244849
3. [3]Pringsheim T, Okun MS, Müller-Vahl K, et al. Practice guideline recommendations summary: Treatment of tics in people with Tourette syndrome and chronic tic disorders. Neurology, 2019.PMID 31061208
4. [8]Robertson MM. A personal 35 year perspective on Gilles de la Tourette syndrome: prevalence, phenomenology, comorbidities, and clinical management. Lancet Psychiatry, 2015.PMID 26359614