Movement Disorders Emergencies Part 2 Hyperkinetic Disorders

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NEUROLOGICAL REVIEW Movement Disorders Emergencies Part 2 Hyperkinetic Disorders

Bradley J. Robottom, MD; Stewart A. Factor, DO; William J. Weiner, MD

lthough movement disorders do not usually present as neurologic emergencies, there are times when the abrupt onset of an unusual movement abnormality results in emergency department or intensive care unit consultations. Part 1 of this review discussed hypokinetic movement disorders emergencies. Part 2 provides a diagnostic approach Ato the recognition and treatment of hyperkinetic movement disorders emergencies by identifying phenomenology and reviewing common etiologies. Arch Neurol. 2011;68(6):719-724

Movement disorders most often have an inflammatory disorders and may be acute insidious onset and a slowly progressive in onset. Sydenham chorea is the most com- course and are not associated with emer- mon cause of acquired, childhood-onset gency situations. In part 1, we addressed chorea.1 Sydenham chorea is the neuro- hypokinetic movement disorders emer- logic manifestation of rheumatic fever and gencies focusing on drug-induced emer- is sufficient to make the diagnosis of rheu- gencies and acute complications of Par- matic fever.2 Its incidence has declined dra- kinson disease. Part 2 focuses on the matically with the widespread availability phenomenology of hyperkinetic move- of penicillin; nevertheless, Sydenham cho- ment disorders (chorea, ballism, myoclo- rea remains prevalent in areas where ac- nus, and dystonia) as the key to appropri- cess to health care is limited.3,4 In addition ate recognition and treatment in the to chorea, which may be generalized or emergent situation. Key clinical features hemichorea, additional features of Syden- of hyperkinetic movement disorders are ham chorea include behavioral changes (ob- presented in Table 1. sessions, compulsions, hyperactivity, and emotional lability), weakness, hypotonia, HYPERKINETIC DISORDERS and, rarely, vocalizations.5 Symptoms may begin abruptly, from 1 to 6 months after Chorea streptococcal pharyngitis.6 The diagnosis is made clinically, though elevated antistrep- Chorea consists of involuntary, irregular, tolysin O antibody titers are supportive. purposeless movements that “flow” into one Treatment with penicillin may prevent the another in a random fashion. Though of- cardiac complications of rheumatic fever ten referred to separately, the distinction and is sometimes continued for several years between chorea, athetosis, ballismus, and as prophylaxis.7 If Sydenham chorea re- dystonia is somewhat arbitrary and relates quires treatment, 1 prospective, nonran- more to speed, amplitude, and duration of domized trial suggested that valproic acid the movement rather than underlying pa- or carbamazepine may be used.1 Based on thology. A combination of these move- observational data, dopamine receptor ments is often encountered in a single blockers or dopamine depleters are also rec- patient. Chorea may result from toxic/ ommended.8 metabolic, vascular, and infectious/ Chorea gravidarum usually begins in the first or early second trimester.9 Chorea may Author Affiliations: Department of Neurology, University of Maryland School of be unilateral or bilateral, often involving the Medicine, Baltimore (Drs Robottom and Weiner); and Movement Disorders face as well as the limbs. Dysarthria is com- Program, Emory University School of Medicine, Atlanta, Georgia (Dr Factor). mon.10 Chorea usually resolves by the third

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©2011 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/26/2021 Table 1. Clinical Definitions of Hyperkinetic Table 2. Etiologies of Acute-Onset Chorea Movement Disorders Etiology Hyperkinetic Vascular Movement Disorder Clinical Definition Ischemic stroke Chorea Involuntary, irregular, purposeless movements Hemorrhagic stroke that “flow” into one another in a random Cavernous angioma fashion Cerebral anoxia Ballism Rapid, large-amplitude proximal movements Metabolic that are sometimes described as “flinging” Nonketotic hyperglycemia May be present with chorea, representing an Hypoglycemia extreme end of the spectrum of chorea Hyperthyroidism Myoclonus Sudden, brief shocklike movements Pregnancy May be due to muscle contraction (positive Structural myoclonus) or loss of muscle tone (negative Basal ganglia mass lesion myoclonus or asterixis) Cerebellar mass lesion Tics Brief, paroxysmal movements or vocalizations Thalamotomy or subthalamotomy sometimes accompanied by premonitory urge Inflammatory May be stereotyped Multiple sclerosis Unlike other hyperkinetic movements, may be Sarcoidosis voluntarily suppressed for a short period Infectious Dystonia Involuntary, sustained muscle contractions that Cryptococcal granuloma produce twisting or squeezing movements Toxoplasmosis Often accompanied by abnormal posture Tuberculoma Human immunodeficiency virus encephalitis Sydenham chorea trimester or disappears within hours after delivery.11 Al- Autoimmune though chorea gravidarum is rarely an emergency, it is likely Systemic lupus erythematosus Antiphospholipid antibody syndrome that neurologists will encounter this entity in the context Scleroderma of an emergent inpatient consultation on a maternity ward. Behc¸et disease The antiphospholipid syndrome may result in acute Iatrogenic generalized chorea. Antiphospholipid syndrome may be Anticonvulsants primary or secondary to systemic lupus erythematosus. Oral contraceptives Antiphospholipid syndrome is thought to be the most Levodopa common cause of chorea gravidarum in industrialized na- Cocaine 12 Amphetamines tions. Rarely is chorea the sole manifestation of an- Alchohol, intoxication and withdrawal tiphospholipid syndrome, but a high index of suspicion is important because of the other potentially cata- strophic manifestations (eg, deep venous thrombosis, pul- (Figure 1). Magnetic resonance imaging findings re- monary emboli, stroke, thrombotic microangiopathy, sult from ischemic injury due to hyperviscosity and re- thrombocytopenia, and hemolytic anemia) that could oc- gional metabolic failure. Like hemiballism secondary to cur with failure to diagnose and treat antiphospholipid stroke, the movements typically subside over a period of syndrome.12 Other metabolic causes include hyperthy- months. In some patients, abnormal movements re- roidism and hyperglycemia (Table 2). verse when the glucose level is normalized. Resolution of magnetic resonance imaging signal change correlates Hemichorea-Hemiballism with clinical improvement in chorea.17 If treatment is re- quired (eg, violent, self-injurious, exhausting, or dis- Hemiballism refers to large-amplitude, flinging move- tressing movements), dopamine receptor blockers or ments of one side of the body that can be violent. As hemi- dopamine depleters such as tetrabenazine or reserpine ballismus resolves over days to weeks, the movements are used (Table 3). Because the movements usually re- often become choreiform. Historically, the most com- solve over time,18 medication should be tapered after 3 mon cause of hemiballism was stroke involving the sub- months and the patient, reevaluated. thalamic nucleus. However, this etiology is rare, with an annual incidence of less than 1 per 100 000 in a popu- Myoclonus lation-based study from Belgrade, Serbia.13 Although stroke remains the most common cause, only a minor- Myoclonus consists of sudden, brief shocklike move- ity of cases have lesions within the contralateral subtha- ments that may be due to muscle contraction (positive lamic nucleus.14-16 The second most commonly re- myoclonus) or loss of muscle tone (negative myoclonus ported cause of hemiballism is nonketotic hyperglycemia. or asterixis). Neurologists are often emergently con- With this disorder, chorea, or ballism, may be unilateral sulted in the intensive care unit to see patients with my- or bilateral. It occurs more in women,17 and it may be oclonus as a result of toxic/metabolic derangements or the initial presentation of diabetes mellitus. Magnetic reso- cerebral anoxia. It is also seen in serotonin syndrome and nance T1-weighted images demonstrate hyperintensity neuroleptic malignant syndrome. Medications includ- in the putamen, caudate nucleus, and globus pallidus17 ing monoamine oxidase inhibitors, selective serotonin

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©2011 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/26/2021 reuptake inhibitors, serotonin-norepinephrine reup- lenting, generalized multifocal myoclonus involving the face, take inhibitors, tricyclic antidepressants, opiates, le- limbs, and axial musculature in comatose patients,” is omi- vodopa, gabapentin, triptans, lysergic acid diethylam- nous.22 The chance of good recovery in this setting is ex- ide (LSD), amphetamines, cocaine, and 3,4- ceedingly low,23 and the likelihood of any outcome other methylenedioxymethamphetamine (MDMA or ecstasy) than a poor one is 0% (95% confidence interval, 0%-8.8%).22 may cause myoclonus. Hepatic and uremic encephalopa- A “poor outcome” is defined as death or persisting uncon- thies are the most common metabolic derangements re- sciousness after 1 month or death, persisting unconscious- sulting in myoclonus and asterixis.19,20 ness, or severe disability requiring full nursing care after 6 Cerebral anoxia may result in 2 distinct myoclonic syn- months. Postanoxic myoclonus (Lance-Adams syn- dromes, myoclonus status epilepticus and postanoxic my- drome24) usually occurs after recovery from an anoxic event. oclonus (Figure 2). Myoclonus status epilepticus may be- The action myoclonus seen after recovery from anoxia is gin in the hours immediately after a cerebral anoxic event. generated by abnormal cortical discharges. At rest, the move- This occurs in approximately 30% of comatose adult sur- ments are absent, but with muscle activation, they can be- vivors of cardiac arrest.21 The presence of myoclonus sta- come disabling. This syndrome may improve over years.25 tus epilepticus, defined as “spontaneous, repetitive, unre- If a patient requires treatment, clonazepam, primidone, valproic acid, or levetiracetam may be used (Table 3). Suc- cessful treatment may require a combination of agents.26 The acute onset of focal asterixis or myoclonus should prompt the search for an underlying structural lesion, usually located in the contralateral thalamus.27

Tics

Tics are either brief paroxysmal movements or vocalizations that are sometimes accompanied by a premonitory urge. They may be stereotyped and, unlike other hyperkinetic movements, may be voluntarily suppressed for a short period. Motor tics are common in schoolchildren, with a prevalence of 3.2% to 9.6%.28 Even though it is rare for tics to present as an emergency, 2 situations may bring a patient with a tic disorder for emergency evaluation: tic exacerbation and neurologic compromise secondary to tics. Tic disorders wax and wane and some factors lead to marked exacerbation of tic severity including fatigue, stress (physical or emotional), infection, and medications. When this occurs, the dramatic increase in severity (amplitude, vio- lence, or frequency) may be quite alarming to patients and their families. Medications used to treat comorbid condi- Figure 1. T1-weighted axial magnetic resonance image with signal hyperintensity in the putamen, caudate, and globus pallidus in a patient with tions (eg, attention-deficit/hyperactivity disorder or hyperglycemic hemichorea. obsessive-compulsive disorder), such as stimulants29 and

Table 3. Treatment of Hyperkinetic Movement Disorders

Recommended Maximum Movement Disorder Medication Class Medication Initial Daily Dose, mg Daily Dose, mg Chorea Neuroleptic Haloperidol 0.5 8 Risperidone 0.5 6 Dopamine-depleting agenta Tetrabenazine 12.5 75 Benzodiazepine Clonazepam 0.5 6 Myoclonus Anticonvulsant Valproic acid 750 Titrate to serum level Levetiracetam 500 3000 Primidonea 12.5 750 Benzodiazepine Clonazepam 0.5 6 Tics Neuroleptic Haloperidol 0.5 8 Risperidone 0.5 6 Dopamine-depleting agenta Tetrabenazine 12.5 75 Antihypertensivea Clonidine hydrochloride 0.1 0.6 Guanfacine hydrochloride 1 3 Acute dystonic reaction Anticholinergic Benztropine mesylate 1 6 Diphenhydramine 25 400

a These agents are generally not helpful in short-term treatment but can be given with a neuroleptic that could eventually be discontinued.

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©2011 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/26/2021 antidepressants,30,31 are often reported to exacerbate tics, unremitting dystonic spasms may lead to hyperpyrexia, although a controlled trial did not confirm this.32 In the dehydration, respiratory failure, and rhabdomyolysis emergency department, tics should be diagnosed, and po- with renal failure.37 Most patients require intensive care tential exacerbating factors including psychiatric ones unit admission because orally administered agents are should be identified and removed. Pharmacologic treat- insufficient to arrest the dystonic spasms. The usual thera- ment, if needed, can be initiated. Initial treatment for de- peutic approach is to use combinations of agents includ- bilitating tics uses a neuroleptic or a dopamine-depleting ing anticholinergics, benzodiazepines, catecholamine- agent (Table 3). Patients with focal tics may benefit from depleting agents, and dopamine receptor blockers.37,38 botulinum toxin injections, but this treatment is not help- Extreme cases may require general anesthesia or para- ful emergently.33 Neurologic compromise secondary to tics lyzing agents. Refractory cases may respond to neuro- is uncommon; however, severe tics can cause both com- surgical intervention, either pallidotomy or deep brain pressive neuropathies34 and cervical myelopathy.35 stimulation of the globus pallidus interna, although this surgery is not an emergent procedure.39 Intrathecal Status Dystonicus baclofen therapy has been used successfully in some patients with status dystonicus.40 Patients with primary and secondary dystonia can rarely experience acute worsening with generalized, severe, dys- Acute Dystonic Reaction tonic spasms called dystonic storm or status dystonicus.36 These unremitting dystonic spasms may be life Acute dystonic reaction is most commonly seen after ex- threatening. Reported precipitants for status dystonicus posure to dopamine receptor blockers, both neuroleptics include infection, medication changes, and trauma. The and antiemetics. Dystonia begins within 24 hours of ex- posure, and 90% of reactions occur within 5 days.41 Acute A B dystonic reactions are less common than tardive dyskinesia or drug-induced parkinsonism, affecting approximately 6% of patients exposed to “typical” neuroleptics and 1% to 2% of those exposed to “atypical” neuroleptics.42 Clinical manifestations are diverse, usually affecting the head and neck (Figure 3). Laryngeal dystonia, blepharospasm, cervical dystonia, oculogyric crisis, and focal limb dystonia have all been reported. Acute dystonic reactions are more common in young men,43 while tardive dyskinesia and drug-induced parkinsonism are more common in elderly individuals.42 Treatment with an intravenous anticholinergic agent, such as benztropine mesylate (1-2 mg) or diphenhydramine (25-50 mg), is very Figure 2. Fluid-attenuated inversion recovery (A) and diffusion-weighted (B) axial magnetic resonance imaging sequences demonstrating typical findings effective (Table 3). Because of the possibility of a reoccur- of anoxic brain injury including signal hyperintensity affecting the basal rence, a short oral course of an anticholinergic (4-7 days) ganglia, thalamus, and cortical ribbon. may be necessary.42 After an acute dystonic reaction,

Figure 3. Photographs demonstrating dystonia affecting the head and neck. The dystonic posture is complex, consisting of rotational torticollis, anterocollis, and shoulder elevation.

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©2011 American Medical Association. All rights reserved. Downloaded From: https://jamanetwork.com/ on 09/26/2021 patients are at higher risk for future dystonic reactions when Pharmaceuticals and served as an investigator for clini- exposed to other dopamine receptor blockers.44 cal trials sponsored by the National Institute of Neuro- logical Disorders and Stroke, Westat, Elan Pharmaceu- Acute Torticollis ticals, and Medivation. Dr Weiner reports receiving research support from Santhera, Boehringer Ingelheim, Acute nontraumatic torticollis occurs more commonly in and the National Institutes of Health and has served in children than adults and should be considered a medical advisory or consulting roles for Santhera, Novartis, emergency. While this disorder is unlikely to be a pri- GlaxoSmithKline, and Boehringer Ingelheim. Dr Factor mary neurologic condition (dystonia), neurologists may reports receiving grant support from Teva, Ipsen, and be asked to evaluate the patient. Conditions that present Schering-Plough and has served as a consultant to UCB, with torticollis in children include posterior fossa tu- Allergan, Lundbeck, and Boehringer Ingelheim. mors,45 cervical cord tumors,46 and infection. Acute in- 47 fectious torticollis, or Grisel syndrome, may follow a num- REFERENCES ber of infections including pharyngitis, tonsillitis, mastoiditis, or other infections involving the head or neck. 1. Genel F, Arslanoglu S, Uran N, Saylan B. Sydenham’s chorea: clinical findings It is secondary to atlantoaxial rotatory subluxation sec- and comparison of the efficacies of sodium valproate and carbamazepine regimens. ondary to infection involving the soft tissue surrounding Brain Dev. 2002;24(2):73-76. the cervical spine. The majority of cases described have 2. Shiffman RN. Guideline maintenance and revision: 50 years of the Jones criteria been in patients younger than 13 years.48 Physical exami- for diagnosis of rheumatic fever. 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Correction

Error in Byline. In the Observation titled “Bilateral Pallidal Stimulation for X-Linked Dystonia Parkinson- ism” by Wadia et al, published in the August 2010 issue of the Archives (2010;67[8]:1012-1015), an author’s name was listed incorrectly. Dr Torres Diaz’s name should have appeared as Cristina V. Torres Diaz, MD. The article has been corrected online.

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