Update on pediatric dystonias: etiology, epidemiology, and management

Abstract

Dystonia is a movement disorder characterized by sustained muscle contractions producing twisting, repetitive, and patterned movements or abnormal postures. Dystonia is among the most commonly observed movement disorders in clinical practice both in adults and children. It is classified on the basis of etiology, age at onset of symptoms, and distribution of affected body regions. Etiology: The etiology of pediatric dystonia is quite heterogeneous. There are many different genetic syndromes and several causes of symptomatic syndromes. Dystonia can be secondary to virtually any pathological process that affects the motor system, and particularly the basal ganglia. Classification: The etiological classification distinguishes primary dystonia with no identifiable exogenous cause or evidence of neurodegeneration and secondary syndromes. Treatment: Treatment for most forms of dystonia is symptomatic and includes drugs (systemic or focal treatments, such as botulinum toxin) and surgical procedures. There are several medications including anticholinergic, dopamine-blocking and depleting agents, baclofen, and benzodiazepines. In patients with dopamine synthesis defects L-dopa treatment may be very useful. Botulinum toxin treatment may be helpful in controlling the most disabling symptoms of segmental or focal dystonia. Long-term electrical stimulation of the globus pallidum internum appears to be especially successful in children suffering from generalized dystonia.

Challenging neurological symptoms in paediatric palliative care: An approach to symptom evaluation and management in children with neurological impairment

“…Among enteral medications, anticholinergic treatment is the most common (19,20). The efficacy and tolerability of anticholinergic medications (trihexyphenidyl and benztropine) for dystonia in children is poorly documented and, therefore, physicians must proceed with caution, starting with small dosages and increasing slowly as needed, balancing benefit and side effects.…”

“…It is essential to understand the potential side effects of anticholinergic and monitor appropriately; this includes reduced diaphoresis (increased body temperature), dilated pupils, decreased bodily fluids (dry mouth, dry eyes), erythema of the skin and confusion/ delirium (20). Other enteral medications that can be considered for dystonia (with less evidence) are benzodiazepines (diazepam, nitrazepam), GABA-receptor agonists (baclofen) and dopamine-depleting agents (tetrabenazine) (19)(20)(21). Drugs ordinarily reserved for dopamine-responsive dystonia (carbidopa-levedopa) may also be considered and trialed in specific situations, in consultation with a neurologist (19,20).…”

“…Other enteral medications that can be considered for dystonia (with less evidence) are benzodiazepines (diazepam, nitrazepam), GABA-receptor agonists (baclofen) and dopamine-depleting agents (tetrabenazine) (19)(20)(21). Drugs ordinarily reserved for dopamine-responsive dystonia (carbidopa-levedopa) may also be considered and trialed in specific situations, in consultation with a neurologist (19,20). Finally, botulinum toxin A injection is the treatment of choice for most types of focal dystonia (19,20).…”

“…Drugs ordinarily reserved for dopamine-responsive dystonia (carbidopa-levedopa) may also be considered and trialed in specific situations, in consultation with a neurologist (19,20). Finally, botulinum toxin A injection is the treatment of choice for most types of focal dystonia (19,20). Clinical experience indicates that anticholinergic medications and tetrabenazine are first-line treatments; that said, dystonia is a complex symptom and often very delicate to manage appropriately.…”

“…Neurosurgical approaches, including deep-brain stimulation of the globus pallidum internum, are well established for treatment of dystonia; however, these would be considered to be extreme and invasive measures in a palliative setting (19,20,22).…”