Dystonic storms: a practical management problem

Clinico-Etiological Spectrum and Functional Outcomes of Children with Pre-Status Dystonicus and Status Dystonicus (SD): A Descriptive Study

Background

Status dystonicus (SD) is a life-threatening movement disorder emergency characterized by increasingly frequent and severe episodes of generalized dystonia, requiring urgent hospital admission. The diverse clinico-etiological spectrum, high risk of recurrence, and residual disabilities complicate functional outcomes.

Aim

We aim to describe the clinico-etiological spectrum, radiology, therapeutic options, and follow-up of patients with pre-status dystonicus (pre-SD) and SD.

Methodology

A cross-sectional retrospective study was carried out in a tertiary care referral center. The clinical, laboratory, and radiology data of all patients aged less than 18 years with pre-SD and SD from January 2010 to December 2020 were collected. The Dystonia Severity Assessment Plan (DSAP) scale for grading severity and the modified Rankin Scale (mRS) for assessing outcome were used at the last follow-up visit.

Results

Twenty-eight patients (male:female: 2.1:1) experiencing 33 episodes of acute dystonia exacerbation were identified. The median age at the onset of dystonia and SD presentation was 8.71 (range: 0.25-15.75) and 9.12 (range: 1-16.75) years, respectively. Four patients experienced more than one episode of SD. The etiological spectrum of SD includes metabolic (Wilson's disease-13, L-aromatic amino acid decarboxylase deficiency-one, and Gaucher's disease-one), genetic (neurodegeneration with brain iron accumulation-three and KMT2B and THAP 1 gene-related-one each), structural-three, post-encephalitic sequelae (PES)-four, and immune-mediated (anti-NMDA receptor encephalitis-one). Five patients had pre-SD (DSAP grade 3), and 23 patients had established SD (DSAP grade 4-17 and DSAP grade 5-six). The Rapid escalation of chelation therapy precipitated SD in 11 patients with Wilson's disease. Febrile illness or pneumonia precipitated SD in nine patients. Twenty-three episodes of SD required midazolam infusion in addition to anti-dystonic medications. The median duration of hospital stay was 10 days (range: 3-29). Twenty-three patients had resolution of SD but residual dystonia persisted, while two patients had no residual dystonia at follow-up. Three patients succumbed owing to refractory SD and its complications.

Conclusion

Early identification of triggers, etiology, and appropriate management are essential to calm the dystonic storm.

Status Dystonicus in Children: A Cross-Sectional Study and Review of Literature

Background: Status dystonicus is a life-threatening, underrecognized movement disorder emergency. We aimed to ascertain the etiology, clinical presentation, complications, and outcomes of status dystonicus in children and reviewed the literature for similar studies. Methods: Records of all children aged <14 years admitted to a single center with status dystonicus between 2014 and 2018 were reviewed. Results: Twenty-four children (75% male) were identified with status dystonicus. The annual incidence rate was 0.05 per 1000 new admissions <12 years of age. The mean age at presentation was 6.3 ± 3.6 years. Median duration of hospital stay was 10.5 days (interquartile range 5-21.7). The severity of dystonia at presentation was grade 3 (n = 9; 37.5%) and 4 (n = 9; 37.5%). The most common triggering factor was intercurrent illness/infection (n = 18; 75%). The most common underlying etiologies were cerebral palsy (n = 8; 33.3%), complicated tubercular meningitis (n = 3; 12.5%), and mitochondrial disorders (n = 3; 12.5%). Basal ganglia involvement was seen in 15 cases (62.5%). Respiratory and/or bulbar compromise (n = 20; 83.3%) and rhabdomyolysis (n = 15; 62.5%) were most commonly seen. Oral trihexyphenidyl (96%) followed by oral or intravenous diazepam (71%), oral baclofen (67%), and midazolam infusion (54%) were the most common drugs used. Clonidine was used in 33% cases, without any significant side effects. Three children died owing to refractory status dystonicus and its complications; the mortality rate was 12.5%. Conclusion Status dystonicus is a neurologic emergency in children with severe dystonia, with significant complications and a high mortality rate. Static and acquired disorders are more common than heredo-familial causes. Identification and treatment of infection in children is important as the majority of cases are triggered by an intercurrent infection.

Clinical spectrum and management of dystonia in patients with Japanese encephalitis: A systematic review

BACKGROUND

Japanese encephalitis (JE) is a potentially fatal viral infection with a wide range of manifestations and can also present with a variety of movement disorders (MD) including dystonia. Dystonic features in JE are uncommon. Here, we have tried to summarize the clinical features and management of dystonia among JE patients with a comprehensive literature search.

METHODS

Various databases, including PubMed, Embase, and Google Scholar, were searched against the predefined criteria using suitable keywords combination and boolean operations. Relevant information from observational and case studies was extracted according to the author, dystonic features, radiological changes in the brain scans, treatment options, and outcome wherever provided.

RESULT

We identified 19 studies with a total of 1547 JE patients, the diagnosis of which was confirmed by IgM detection in serum and/or cerebrospinal fluid in the majority of the patients (88.62%). 234 (15.13%) of JE patients had dystonia with several types of focal dystonia being present in 131 (55.98%) either alone or in combination. Neuroimaging showed predominant involvement of thalami, basal ganglia, and brainstem. Oral medications including anticholinergics, GABA agonists, and benzodiazepines followed by botulinum toxin were the most common treatment modalities.

CONCLUSION

Dystonia can be a disabling consequence of JE, and various available medical therapies can significantly improve the quality of life. Owing to insufficient studies on the assessment of dystonia associated with JE, longitudinal studies with a larger number of patients are warranted to further clarify the clinical course, treatment, and outcome of dystonia.

Status dystonicus: management and prevention in children at high risk

BACKGROUND

Status dystonicus (SD) is a movement disorder emergency associated with significant morbidity and life-threatening events that requires immediate and effective treatment. Nevertheless, SD is currently an under-recognized and undertreated condition, partly due to the lack of a standard definition and because it can be the acute complicated course of both primary and secondary dystonias. In subjects with SD, due to  the delay of identification and  lacking prevention of trigger and precipitant factors, intensive care management is consistently required.

OBJECTIVES

We performed a critical review of this topic, outlining clinical features and linked genetic disorders to recognize subject at higher risk of SD, describing precipitant and trigger factors and proposing potential pharmacological treatment strategies in order to prevent hospitalization.

RESULTS

Genetic predisposition included: primary dystonias particularly in the case of  TOR1A mutation; epileptic encephalopathy such as ARX and GNAO1 genetic variants and neurodegenerative disorders as PANK2. Early recognition of SD should be oriented by the following sign and symptoms: fever, tachycardia, respiratory change, hypertension, sweating and autonomic instability, elevated serum CK. Pain, fever and dehydration are main trigger factors that have to be prevented or quickly controlled. Achieving sleep could be the first therapeutic option in those with high risk of developing SD. Recently, enteral or transdermal clonidine as safety and efficacy therapeutic alternative was proposed.

CONCLUSION

Recognizing high risk children for Status dystonicus from the onset of subtle signs and avoiding trigger factors could drive towards better management avoiding intensive treatments.

Rethinking status dystonicus

Status dystonicus is a movement disorder emergency that has been a source of controversy in terms of terminology, phenomenology, and management since it was first described in 1982. Here we argue that the current use of the term status dystonicus falls well short of the precision needed for either clinical or academic use. We performed a critical review on this topic, describing possible pathophysiological mechanisms and areas of uncertainties. This review also addresses the problems derived by the extreme clinical heterogeneity of this condition, as the lack of an objective criterion useful for the definition, or the fact that status dystonicus may present not only in the context of a known dystonic syndrome. We propose a new possible definition that includes not only dystonia but also other hyperkinetic movements in the wide range of movement disorders that can be seen during an episode. The new definition keeps the term status dystonicus and highlights the fact that this is a medical emergency based on the impairment of bulbar and/or respiratory function requiring hospital admission as the principal feature. Furthermore, the new definition should not consider as necessary unspecific features as patient's condition at baseline, the distribution of dystonia, occurrence of systemic symptoms such as fever or laboratory findings. We hope that this proposal will stimulate the debate on this subject among our peers, further developing a clinical and pathophysiological understanding of status dystonicus. © 2017 International Parkinson and Movement Disorder Society.

Dystonic storm: a practical clinical and video review

Dystonic storm is a frightening hyperkinetic movement disorder emergency. Marked, rapid exacerbation of dystonia requires prompt intervention and admission to the intensive care unit. Clinical features of dystonic storm include fever, tachycardia, tachypnea, hypertension, sweating and autonomic instability, often progressing to bulbar dysfunction with dysarthria, dysphagia and respiratory failure. It is critical to recognize early and differentiate dystonic storm from other hyperkinetic movement disorder emergencies. Dystonic storm usually occurs in patients with known dystonia, such as DYT1 dystonia, Wilson’s disease and dystonic cerebral palsy. Triggers such as infection or medication adjustment are present in about one-third of all events. Due to the significant morbidity and mortality of this disorder, we propose a management algorithm that divides decision making into two periods: the first 24 h, and the next 2–4 weeks. During the first 24 h, supportive therapy should be initiated, and appropriate patients should be identified early as candidates for pallidal deep brain stimulation or intrathecal baclofen. Management in the next 2–4 weeks aims at symptomatic dystonia control and supportive therapies.

Status dystonicus: a practice guide

Status dystonicus is a rare, but life-threatening movement disorder emergency. Urgent assessment is required and management is tailored to patient characteristics and complications. The use of dystonia action plans and early recognition of worsening dystonia may potentially facilitate intervention or prevent progression to status dystonicus. However, for established status dystonicus, rapidly deployed temporizing measures and different depths of sedation in an intensive care unit or high dependency unit are the most immediate and effective modalities for abating life-threatening spasms, while dystonia-specific treatment takes effect. If refractory status dystonicus persists despite orally active anti-dystonia drugs and unsuccessful weaning from sedative or anaesthetic agents, early consideration of intrathecal baclofen or deep brain stimulation is required. During status dystonicus, precise documentation of dystonia sites and severity as well as the baseline clinical state, using rating scales and videos is recommended. Further published descriptions of the clinical nature, timing of evolution, resolution, and epidemiology of status dystonicus are essential for a better collective understanding of this poorly understood heterogeneous emergency. In this review, we provide an overview of the clinical presentation and suggest a management approach for status dystonicus.

Management of status dystonicus in children. Cases report and review

Status dystonicus (SD) is a medical emergency weighed by a relevant morbidity and mortality. It mainly affects patients with primary or secondary dystonia and is often triggered by events such as fever, infections, exposure medications or their abrupt cessation. We report on three patients presenting with SD. Two of them were affected by a static encephalopathy and the other one by a neurodegenerative disorder such as megalencephalic leukoencephalopathy with subcortical cysts (MLC). To our knowledge this is the first patient affected by MLC presenting with SD. All our patients underwent continuous infusion of midazolam, in association with pimozide and trihexyphenidyl, which led to complete resolution of muscular spasms in two patients. In the other one a complete cessation of dystonic spasms was obtained after intrathecal baclofen. From a therapeutic point of view there are no evidence-based management guidelines in SD. The approach is empiric and based on very limited anecdotal reports. On the basis of our observations and an extensive review of the literature we delineated a possible therapeutic strategy of SD in children.

Identification and management of deep brain stimulation intra- and postoperative urgencies and emergencies

Deep brain stimulation (DBS) has been increasingly utilized for the therapeutic treatment of movement disorders, and with the advent of this therapy more postoperative urgencies and emergencies have emerged. In this paper, we will review, identify, and suggest management strategies for both intra- and postoperative urgencies and emergencies. We have separated the scenarios into 1--surgery/procedure related, 2--hardware related, 3--stimulation-induced difficulties, and 4--others. We have included ten illustrative (and actual) case vignettes to augment the discussion of each issue.

Movement disorder emergencies

Movement disorder emergencies include any movement disorder which evolves over hours to days, in which failure to appropriately diagnose and manage can result in patient morbidity or mortality. It is crucial that doctors recognize these emergencies with accuracy and speed by obtaining the proper history and by being familiar with the phenomenology of frequently encountered movements. These disorders will be discussed based on the most common associated involuntary movement, either parkinsonism, dystonia, chorea, tics or myoclonus, and, when available, review the workup and treatment options based on the current literature.

Management of status dystonicus: Our experience and review of the literature

Status dystonicus (SD) is a life threatening disorder that develops in patients with both primary and secondary dystonia, characterized by acute worsening of symptoms with generalized and severe muscle contractions. To date, no information is available on the best way to treat this disorder. We review the previously described cases of SD and two new cases are reported, one of which occurring in a child with static encephalopathy, and the other one in a patient with pantothenate kinase-associated neurodegeneration. Both patients were admitted to an intensive care unit and treated with midazolam and propofol. This approach proved to be useful in the former while the progressive nature of the dystonia of the second patient required the combination of intrathecal baclofen infusion and bilateral pallidal deep brain stimulation. We believe that a rapid and aggressive approach is justified to avoid the great morbidity and mortality which characterize SD. Our experience, combined with the data available in the literature, might permit to establish the best strategies in managing this rare and severe condition.

Movement disorder emergencies

For the past 4 years, Dr. Stanley Fahn and I have given a course at the American Academy of Neurology annual meeting on the topic of movement disorder emergencies. The purpose of this review article is to summarize the topic and to present it to readers of this journal. The text of this article has appeared in nearly the same form as the Academy syllabus accompanying our course. It is being presented here so that readers of the journal may review the material.

Status dystonicus: study of five cases

Status Dystonicus (SD) is characterized by generalized muscle contractions in dystonic patients. We report 5 cases of SD, two of which in patients with dystonic cerebral palsy, one in a patient with primary segmental dystonia, one in a patient with Hallervorden-Spatz syndrome and one in a patient with Wilson's disease (WD). Three patients were admitted to an intensive care unit and treated with propofol and midazolam, and two were submitted to neurosurgical procedures (bilateral pallidotomy and bilateral pallidal deep brain stimulation). Triggering factors were identified in three patients as follows: infection, stress-induced and zinc therapy for WD. On follow-up, two patients presented with significant improvement of dystonia, whereas the other three cases the clinical picture ultimately returned to baseline pre-SD condition.

Status dystonicus and Hallervorden-Spatz disease: treatment with intrathecal baclofen and pallidotomy

Severe dystonia or status dystonicus is a life threatening disorder that develops in patients with both primary and secondary dystonia. We present the case of a 9-year-old boy with Hallervorden-Spatz disease (HVS) who developed status dystonicus, failing to respond to high dose oral therapy with multiple antidystonic agents. High dose intravenous sedating agents combined with endotracheal intubation and mechanical ventilation were required to control the spasms. Alleviation of the spasms was achieved by a combination of temporary intrathecal baclofen infusions and bilateral pallidotomy. Although it could be argued this is a situation where only palliative measures should be used, we believe a relatively aggressive approach was justified. It relieved the intense pain associated with the spasms and allowed the child to be discharged home without the prolonged stay in intensive care, morbidity and mortality, which characterize status dystonicus.

Movement disorder emergencies in the perioperative period

Movement disorder emergencies are uncommon in the perioperative period; however, when they occur, then carry significant morbidity. By paying attention to the phenomenology of the movement disorder, the effects of medications administered in the operating room, and unusual sequelae of surgery, neurologists can have a positive impact on the outcome of these patients.

Tetrabenazine in the treatment of severe pediatric chorea

Tetrabenazine (TBZ) is widely used to treat adults with hyperkinetic movement disorders; however, published experience with the drug in pediatric patients is limited. We report on 5 children with severe chorea who were treated with TBZ. TBZ effectively controlled chorea in 4 patients, and despite the need for relatively high doses, it was well tolerated.

Intrafamilial phenotypic variability of the DYT1 dystonia: from asymptomatic TOR1A gene carrier status to dystonic storm

When primary torsion dystonia is caused by a GAG deletion in the TOR1A gene (DYT1 dystonia), it typically presents with an early-onset dystonia involving distal limbs, subsequently spreading to a generalized dystonia. We describe a large family with an unusually broad variability in the clinical features of their dystonia both with regard to severity and age of onset. The proband of this family succumbed in his second decade to malignant generalized dystonia, whereas other family members carrying the same mutation are either asymptomatic or display dystonia that may be focal, segmental, multifocal, or generalized in distribution. One family member had onset of her dystonia at age 64 years, probably the oldest reported in genetically confirmed DYT1 dystonia. We conclude that marked phenotypic heterogeneity characterizes some families with DYT1 dystonia, suggesting a role for genetic, environmental, or other modifiers. These findings have implications for genetic testing and counseling.

Markedly severe dystonia in Japanese encephalitis

Encephalitis has been reported to be a rare cause of severe dystonia. We describe five patients with markedly severe dystonia from Japanese encephalitis. These patients with markedly severe dystonia were seen during the past 8 years as a subgroup of 50 patients with Japanese encephalitis. The diagnosis of markedly severe dystonia was based on increasingly frequent episodes of generalized dystonia with bulbar, respiratory, or metabolic derangement or leading to exhaustion or pain. The diagnosis of JE was based on clinicoradiologic features and a fourfold increase of hemagglutination-inhibiting antibody titers in paired serum. The outcome of the patients was defined as a good, partial, or poor recovery on the basis of 1-year clinical status. All the patients were males, and their ages ranged from 6 to 19 years. Movement disorders appeared 1 to 3 weeks after the illness as the level of consciousness started improving. During the next 1 to 4 weeks, patients began to experience markedly severe dystonia. It was associated with marked axial dystonia resulting in opisthotonus and retrocollis in five patients, jaw-opening dystonia in two patients, teeth clenching in one patient, and oculogyric crisis and neck deviation in another patient. The attacks of markedly severe dystonia lasted for 2 to 30 minutes and occurred as many as 20 to 30 times daily. Other developments included fixed limb dystonia in one patient, severe spasticity and rigidity in five patients, and focal muscle wasting in one patient. These patients had only a modest improvement after treatment. Markedly severe dystonia abated by 2 to 6 months in all the patients who were followed up. Cranial magnetic resonance imaging showed bilateral thalamic involvement in all patients, brainstem involvement in three patients, and basal ganglia involvement in two patients. At the 3-month follow-up, all patients had a poor outcome. At 1 year, one patient had a complete recovery; one had a partial recovery; and two were bedridden. It can be concluded that markedly severe dystonia is an important and serious sequela of Japanese encephalitis and may occur as the result of thalamus, midbrain, or basal ganglia involvement in various combinations.