Pediatric Neurology Quick Talks

Movement DisordersMichael Babcock

Summer 2013

Scenarios

• Scenario 1

• 8 yo boy

• PMHx – dx'd with allergic rhinitis unresponsive to nasal steroids

• 1 year of recurrent neck popping, multiple times daily

• No LOC and is aware of movements

• Pt says he feels “relaxed” after movements

• What is dx? What comorbidities should you ask about? Does he really have rhinitis?

• Scenario 2

-6 yo girl

-in ED with abnormal sustained twisting posture of L arm and neck

-4 recent ER visits for headache with vomiting

-has taken headache medicine for the last 5 days

-no other medications

-no other significant history

-what is diagnosis?

-what is treatment?

Step 1:Observe and Step 2: Describe

• Are the movements normal or abnormal?

• Are they paroxysmal (sudden on/off), continual (repeated again and again), or continuous (non-stop)?

• How does voluntary movement affect abnormal movements?

• Are movements present at rest, posture, action, intention, or combination?

• Do environmental stimuli/emotion precipitate/exacerbate/alleviate?

• Is patient aware of movements?

• Do movements stop with sleep?

Step 3: Classify

• Hyperkinetic (most common)

– Tic

– Tremor

– Myoclonus

– Chorea

• Ballismus

– Athetosis

– Dystonia

– Dyskinesia

– Akathesia

– Myokymia

– Asterixis

• Hypokenitic (uncommon for peds – mainly Parkinsons)

– Bradykinesia

– Freezing

– Rigidity

Step 4: Diagnose and Step 5: Treatment

• Scenario 1

• Tics – Neck popping movements are repetitive and stereotypic, relieve an inner feeling of tension.

• Diagnosis of rhinitis unrelieved with steroids is probably sniffing/throat clearing that is also a tic.

• Diagnosis is Tourette's

• Treatment can be observation unless significantly bothersome or comorbidities.

• Scenario 2

• Dystonia – abnormal twisting movement sustained for a long time.

• Acute onset is likely medication related – she was recently given headache medication, probably dopamine antagonist like phenergan.

• Tx – benedryl

Basal Ganglia Circuit – Just to discuss treatment

Tics

• Taskforce on Childhood Movement Disorders, “tics are repeated, individually recognizable, intermittent movements or movement fragments that are almost always briefly suppressible and are usually associated with awareness of an urge to perform the movement”

• Sometimes difficult for young children to describe urge

• Disappear with sleep

• Often worsened by anxiety

• Transient Tic disorder – 25% of children – tics last less than 1 year

• Chronic Tic disorder – tics last more than 1 year

• Tourette's – Chronic tics with both motor and vocal tics

Tremor

• Rhythmic oscillation around a central point involving one or more body parts.

• Different tremors occur at different times – rest, postural, action, intention

• Rest tremor – Parkinsons, Wilson's

• Postural -physiologic tremor, essential tremor

• Intention – cerebellar disease

Chorea

• Taskforce - “ongoing random-appearing sequence of one or more discrete involuntary movements or movement fragments.”

• Chaotic, purposeless

• Not as rapid as myoclonus

• Can see in CP, Sydenham, Post-pump, kernicterus, hereditary

• Ballism – Large amplitude chorea of proximal muscles

Dystonia

• Task force – “a movement disorder in which involuntary sustained or intermittent muscle contractions cause twisting and repetitive movements, abnormal postures, or both.”

• Dystonic postures are repeated, particular patterns or postures are characteristic of any one patient at a given time.

• Postures maybe be sustained or occur during brief intervals

• Often triggered by certain voluntary movements – writer's cramp.

Others

• Athetosis

– Slow, continuous, writhing movements of distal body parts, especially fingers and hands

– Can see in cerebral palsy and Rett syndrome.

• Myoclonus

– Sudden, brief, shock-like movements

– May be repetitive or rhythmic

• Sterotypies

– Taskforce, “stereotypies are repetitive, simple movements that can be voluntarily suppressed”

– Patterned, episodic, repetative, purposeless

– These are different from tics

– See often in autism, Rett

Benign movements (may need to rule out other causes)

• benign neonatal sleep myoclonus

• benign myoclonus of infancy

• jitteriness

• shuddering

• paroxysmal tonic upgaze of infancy

• spasmus nutans

• benign paroxysmal torticollis

• benign idiopathic dystonia of infancy

Tourette's Syndrome

• Chronic vocal and motor tics

• Comorbidites: ADHD, OCD, anxiety – often these guide treatment

• Tx: only needed if there is physical discomfort, functional problems, or psychosocial problems (class disturbance, self-esteem, social anxiety)

• Tx: alpha-adrengergic meds (clonidine, guanfacine), SSRI, AEDs (topamax, keppra). Can consider antipsychotics but higher side-effect profile – pimozide and haldol.

• Work-up – consider secondary causes if tics begin abruptly (parents remember date), are persistent (don't wax/wane), or particularly problematic.

• Secondary causes:

– Infections (encephalitis, Sydenham's chorea, ?-PANDAS)

– Drugs (stimulants, levodopa, some AEDs, antipsyhcotics

– Toxins (carbon monoxide)

– Other (head trauma, stroke, static encephalopathy, chromosomal abnormalities, neurocutaneous/neuro-degenerative syndromes, schizophrenia)

Sydenham's Chorea

• Most common form of acquired chorea in childhood

• 1-18 months after GAS infection (contrast to carditis and arthritis that appear within 1 month)

• ARF – Chorea alone can lead to presumptive diagnosis.

• Can also have emotional change (deteriorating school performance),psychiatric symptoms-OCD, irritability, hypotonia. grip-strength testing has continuous increase/decrease – Milking sign.

• Work-up: EKG/Echo to look for carditis, ASO, DnaseB

– other causes of chorea – SLE, Huntington's, encephalitis, Wilson's

• Typically improves gradually, mean duration 3-4 months

• Tx – treatment dose penicillin for 10 days, followed by antibiotic ppx against GAS.

• Specific treatment may be needed – depakote, phenobarbital, haldol, pimozide, valium, carbamazepine. Steroids may shorten duration.

Opsoclonus-Myoclonus Syndrome

• Dancing eyes – dancing feet

• Mean age – 2 yo.

• Opsoclonus – uncontrolled, frequent, conjugate, saccidic movement of eyes in all directions.

• can also have ataxia (OMA); irritability, sleep problems

• Auto-immune: Paraneoplastic – neuroblastoma (unknown Ab); parainfectious

• Differential: other causes of myoclonus, ataxia; toxic/metabolic dz, structural

• Work-up – Look for neuroblastoma – CAP MRI, VMA/HVA, MIBG scan. If no neuroblastoma, then MRI brain to look for structural, toxic/metabolic, med review, infections – viral (hep C, Lyme, EBV, HIV, coxsackie, rota, mycoplasma, GAS).

• Tx - Treat movements with immunosuppression- steroids, IVIG, rituximab.

Rett Syndrome• X-linked dominant – mostly sporadic – Mutations in MECP2 gene on Xq28

• 1:10,000 females

• Typically presentation – female at 6-18 months with previously normal growth and development with regression in verbal and motor skills

– Postnatal microcephaly

• Lose purposeful movements of hands

• Sterotypies of hands resembling hand washing and kneading

• Differential – autism, CP, Fragile X, Angelman, leukdoystrophies, neurocutaneous, metabolic disorders, NCL.

• Work-up – MRI, EEG, Chromosome analysis, FISH/methylation for Angelman, metabolic studies

• Can have seizures – need to differentiate from sterotypies

• 80% are ambulatory, though some will lose this during regression period

• Long-term issues – EKG – prolonged QTC. GI – poor growth, GERD, gallbladder, constipation. Respiratory – breath-holding and abnormal breathing. Orthopedic – osteopenia and scolisos.

PREP QuestionA 10 year old boy presents to the emergency department with a 2 day history of progressive

difficulty with speech and coordination. On PE, the restless but otherwise quiet child has a normal mental status and eye movements. His speech is slurred, and he cannot maintain tongue protrusion without an in-and-out darting movement. Continuous flowing and jerky movements occur when he holds his hands outstretched or overhead. Although his grip is strong, he cannot maintain it well because of irregular hand and arm movements. He had a sore throat and fever 2 months ago. You diagnose chorea.

Of the following, the MOST effective treatment for suppressing the chorea for this boy is:

A. Carbamazepine

B. Clonazepam

C. Haloperidol

D. Penicillin

E. Trihexyphenidyl

C. Haloperidol

Chorea- “milk maids grip,” “darting tongue,” continuous flowing and jerky movements- Syndeham: poststrep, autoimmune; ASO, anti-DNAse B- Other conditions associated: SLE, APA, hyperthyroid

Haloperidol: Dopamine receptor blocker; can use low dose; short term therapy typically

Other therapeutic options: Depakote, riperidone Regarding other choices:

- A. Carbamazepine: Anticonvulsant; may induce chorea- B. Clonazepam: Sedating to hit therapeutic dosing- D. Penicillin: Secondary prevention for patients with RF, but doesn't treat

chorea.- E. trihexyphenidyl: reduces dystonia, worsens chorea

References

-Uptodate articles

-on call neurology

-http://www.unifr.ch/biochem/index.php?id=120