Presentation on theme: "Movement Disorders in Children. Overview Childhood movement disorders occur secondary to a wide range of genetic and acquired disorders affecting brain."— Presentation transcript:
Movement Disorders in Children
Overview Childhood movement disorders occur secondary to a wide range of genetic and acquired disorders affecting brain development. Classification by type of abnormal movement – Bradykinetic disorders – Hyperkinetic disorders Classification by Etiology – Primary – Secondary Fixed Structural lesion Degenerative Metabolic Drug Induced Infectious Important point – Any disorder that affects the basal ganglia can cause a wide array of different movement disorders – Static brain injury may nonetheless cause a changing movement disorder, as development and brain plasticity alter the brains response to injury.
Basal Ganglia Group of deep nuclei – Caudate nucleus – Putamen – Globus pallidus – Substantia nigra dopamine-rich pars compacta pars reticularis Inputs: Corpus striatum (caudate nucleus and putamen) receives input from the cerebral cortex and the thalamus Outputs: projects by way of the thalamus to the cerebral cortex and then to the pyramidal system
Bradykinetic vs. Hyperkinetic Bradykinetic disorders – Very rare in children – Parkinson disease is the most common bradykinetic disorder Hyperkinetic disorders – Tic Disorders – Dystonia – Sterotypies – Chorea – Athetoses – Ballismus – Tremor – Myoclonus – Dyskinesia
Tic Disorders Tics are repeated, intermittent movements that are almost always briefly suppressible and are usually associated with awareness of an urge to perform the movement Tourette syndrome : Multiple motor and vocal tics Etiology – Primary: the vast majority – Secondary: Huntingtons, encephalitis, medication induced, carbon monoxide poisoning, neuroacantocytosis
Tics Diagnosis: – Typical movements – Dont occur in sleep – Patient usually unaware of it occurring – Patient can usually suppress for a short time – But when they do, it is accompanied by a discomfort and a strong urge to do the tic (a compulsion) – Wax and wane over time – Worsen with stress Associated with ADHD and OCD – Make sure to ask both of patient and family history PANDAS Treatment – Reassurance Tics tend to wax and wane; most children outgrow them – Medications (when necessary) Stimulants bring out tics; if the have ADHD, they cant use stimulants Tenex Risperidone
Dystonia Involuntary sustained or intermittent muscle contractions that cause twisting and repetitive movements, abnormal postures, or both.
Classification of Dystonia By location – Generalized dystonia affects most or all of the body. – Focal dystonia is localized to a specific part of the body. Blepharospasm, Cervical Dystonia, Task Specific Dystonia (eg Writers cramp) – Multifocal dystonia involves two or more unrelated body parts. – Segmental dystonia affects two or more adjacent parts of the body. – Hemidystonia involves the arm and leg on the same side of the body. By etiology – Primary: by definition, no other neurologic impairment – Secondary: Cerebral Palsy the most common cause in children – Psychogenic
Primary Dystonias Genetic Dystonias – DYT1 dystonia dominantly inherited generalized dystonia typically begins in childhood, affects the limbs first, and progresses A great deal of phenotypic variability – Dopa-responsive dystonia (Segawas disease) onset during childhood and have progressive difficulty with walking. Symptoms characteristically fluctuate and are worse late in the day and after exercise. Some forms are due to mutations in the DYT5 gene for GTP cyclohydrolase 1. Patients with this disorder have dramatic improvements in symptoms after treatment with levodopa – Many other genes that cause dystonic syndromes have been found
Work up of Dystonia Take careful history of medication, drug and supplement use Consider Genetic testing (especially DYT1) Consider empiric trial of levodopa Consider metabolic testing: amino acids, organic acis, Wilsons testing, lysosomal storage diseases Consider MRI
Treatment of Dystonia Botulinum toxin – Particularly for focal dystonias Medications – Anticholinergic agents : trihexyphenidyl and benztropine. – GABAergic agents : benzodiazepines, baclofen – Dopaminergic agents: tetrabenazine – Levodopa for Dopa-responsive dystonia (DRD) Deep brain stimulation (DBS) Physical and other therapies
Sterotypies Repetitive, simple movements that can be voluntarily suppressed. Examples include repetitive chewing, rocking, twirling, or touching movements Most common in children with autism or mental retardation; can occur in otherwise normal children.
Chorea, athetosis and ballismus Chorea – an irregular, rapid, uncontrolled, involuntary, excessive movement that seems to flow randomly from one part of the body to another. – The affected child often appears fidgety or restless and cant sit still Athetosis – A slower writhing and twisting movement. Ballism (ballismus) – chorea that affects proximal joints such as shoulder or hip, leading to large amplitude flailing movements of the limbs
Sydenham chorea Sydenham chorea is a movement disorder characterized by chorea, emotional lability, and hypotonia. It is one of the major clinical manifestations of acute rheumatic fever (ARF). Symptoms of SC usually begin one to eight months after the onset of ARF. The symptoms typically improve gradually, with a mean duration of 12 to 15 weeks ( At least 30 percent of individuals have clinical carditis in association with SC. Diagnosis – The diagnosis of SC is made clinically, based on characteristic neurological findings and a careful cardiac examination. If carditis is present, this confirms the diagnosis. – The antistreptolysin O (ASLO) titer is of limited use in patients with SC, because titers generally peak before the onset of SC symptoms and children without rheumatic fever or SC often have low positive titers of ASLO. – The antideoxyribonuclease (anti-DNAse) B titer is more useful for supporting the diagnosis of SC because it tends to remain elevated longer. – If not clinicually definite, other causes of chorea should be excluded, including systemic lupus erythematosus, Huntingtons disease, and Wilsons disease. Treatment – Most patients with SC recover fully without treatment, with symptoms lasting from a few weeks to one year or more. – For those with significant impairment of motor function and the possibility of self injury consider corticosteroids (prednisone 1 mg/kg daily for two weeks and then tapered over two to three weeks)prednisone – Valproic acid if needed to treat chorea Up to 30 percent of individuals with SC experience a recurrence, usually within a few years of the initial episode. The risk is probably reduced, by chronic treatment with prophylactic antibiotics.
Athetosis Mr8M Mr8M
Work up Take careful history of medication, drug and supplement use If acute onset: throat culture and streptococcal blood antigen test (ASLO, anti-DNAse), electrolytes, magnesium, calcium, thyroid function, CBC Consider amino and organic acid studies, ammonia, antinuclear antigen (ANA), antiphospholipid antibodies (APLA), work up for Wilsons disease (start with ceruloplasmin), evaluation of CBC for acanthocytes. Consider MRI
Treatment of Chorea May be difficult to treat. Taper or discontinue any medications that can cause or worsen chorea In adults, the mainstay of treatment in adults is neuroleptics, including haloperidol and pimozide. In children the incidence of side effects in children is high. Therefore, treatment is usually – Benzodiazepine, particularly clonazepam, diazepam, or clobazam – Valproate, especially in Sydenham's chorea. Sydenham's chorea – There is considerable debate about whether children with Sydenham's chorea due to streptococcal infection should be given long-term antibiotics. There is not yet scientific evidence to support this, although short-term treatment is certainly needed in order to prevent complications such as rheumatic fever.
Tremor A rhythmic back-and-forth or oscillating involuntary movement about a joint.
Classification of Tremor Classification by type of tremor – Rest Tremor Parkinsons, Wilson Disease, Severe essential tremor – Action Tremor Postural Kinetic Intention: Cerebellar Tremor Task Specific Isomeric Classification by Etiology – Physiologic tremor – Essential tremor – Associated w/ Peripheral Neuropathy: Charcot MarieTooth – Psychogenic
Etiology of Tremor Primary Tremors: – Enhanced physiologic tremor – Essential Tremor Static (fixed) injury: Stroke (particularly in the midbrain or cerebellum); multiple sclerosis Degenerative: – Juvenile parkinsonism; Wilson's disease; Huntington's disease; Tay-Sachs disease Chemical/metabolic: – Hyperthyroidism; hyper-adrenaline state (including anxiety or pheochromocytoma); hypomagnesemia; hypocalcemia; hypoglycemia; hepatic encephalopathy Drug-induced – Valproate; lithium; thyroid hormone; albuterol, tricyclic antidepressants; stimulants, neuroleptics; cyclosporine; mercury; thallium; nicotine; lead; manganese; arsenic; cyanide; ethanol Psychogenic tremor Other causes of tremor: – Peripheral neuropathy, cerebellar disease or malformation,spasmus nutans
Essential Tremor Tremor should be the only neurologic manifestation Usually benign, but may progress to a disabling movement disorder. Hereditary ET can begin in infancy – hereditary chin tremor and shuddering attacks.
Work up of Tremor Any medications that may worsen tremor should be avoided, if possible. Check electrolytes, including glucose, calcium and magnesium, thyroid function, copper in the urine (for Wilson's disease), and possibly the amount of adrenaline metabolites (for pheochromocytoma). Consider MRI if the tremor had sudden onset, Consider EEG if there is suspicion for seizures. If parkinsonian features are present, consider a trial of L- DOPA If there is a family history of tremor, it may be helpful to of alcohol ( in the affected family member). This suggests essential tremor.
Treatment of Tremor Often, mild tremor does not require treatment. Medications: – Propranolol – Primidone – benzodiazepines (i.e., clonazepam, diazepam, lorazepam).
Myoclonus Sudden, brief, jerky, shock-like involuntary movements. May be triggered by attempts at voluntary movement, sensory stimulation or startle Myoclonus is not suppressible and is often activated by volitional movement. Negative myoclonus is a sudden involuntary relaxation of a muscle, rather than a contraction. Myoclonus is often associated with epilepsy.