Safety and efficacy of high-dose enteral, intravenous, and transdermal clonidine for the acute management of severe intractable childhood dystonia and status dystonicus: An illustrative case-series

Pharmacological and neurosurgical management of cerebral palsy and dystonia: Clinical practice guideline update

Dystonia, typically characterized by slow repetitive involuntary movements, stiff abnormal postures, and hypertonia, is common among individuals with cerebral palsy (CP). Dystonia can interfere with activities and have considerable impact on motor function, pain/comfort, and ease of caregiving. Although pharmacological and neurosurgical approaches are used clinically in individuals with CP and dystonia that is causing interference, evidence to support these options is limited. This clinical practice guideline update comprises 10 evidence-based recommendations on the use of pharmacological and neurosurgical interventions for individuals with CP and dystonia causing interference, developed by an international expert panel following the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. The recommendations are intended to help inform clinicians in their use of these management options for individuals with CP and dystonia, and to guide a shared decision-making process in selecting a management approach that is aligned with the individual's and the family's values and preferences.

Recommendations for the Management of Initial and Refractory Pediatric Status Dystonicus

Status dystonicus is the most severe form of dystonia with life-threatening complications if not treated promptly. We present consensus recommendations for the initial management of acutely worsening dystonia (including pre-status dystonicus and status dystonicus), as well as refractory status dystonicus in children. This guideline provides a stepwise approach to assessment, triage, interdisciplinary treatment, and monitoring of status dystonicus. The clinical pathways aim to: (1) facilitate timely recognition/triage of worsening dystonia, (2) standardize supportive and dystonia-directed therapies, (3) provide structure for interdisciplinary cooperation, (4) integrate advances in genomics and neuromodulation, (5) enable multicenter quality improvement and research, and (6) improve outcomes. © 2024 International Parkinson and Movement Disorder Society.

Dystonia in children with acquired brain injury

AIM

To quantify the proportion of children who develop dystonia after acquired brain injury (ABI) admitted to a tertiary paediatric intensive care unit (PICU) and analyse the trajectory of dystonia over a 6 month period.

METHODS

Children's Health Ireland at Temple Street PICU electronic database was searched for key terms related to ABI from January 1, 2016 to March 14, 2021. Individuals meeting inclusion criteria were analysed, and clinical data pertinent to ABI, dystonia, treatment and outcomes were reviewed.

RESULTS

Six-hundred and forty-three PICU episodes (580 patients) met search criteria for ABI, with 379 included in the final analysis. Twelve patients developed dystonia following ABI, giving an incidence of 3.2%. The incidence was higher in the hypoxia/anoxia and TBI cohort at 8.3% and 6.2%, respectively. All patients developed dystonia within the first month following ABI (50% by a week). Patients who developed dystonia compared to non-dystonia cohort had a median lower GCS on admission (4.5 versus 7.0, p value 0.032), longer median length of PICU stay (14.0 versus 3.0 days, p value < 0.001) and were older (median age 9.08 versus 4.68 years, p value 0.06). Dystonia persisted in the majority at 6 months (10/11), requiring on-going medical therapies.

CONCLUSION

In our retrospective study, the estimated incidence of dystonia following ABI admitted to the PICU was 3.2%, highest in the hypoxia/anoxia (8.3%) and TBI (6.2%) cohorts. Dystonia emerged early and persisted at 6 months in the majority. This is the first review of dystonia, clinical trajectory and outcomes conducted post-PICU admission for ABI. Future prospective studies are required to determine the true prevalence and burden of disease in the PICU setting.

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.

Prestatus and status dystonicus in children and adolescents

AIM

To critically analyse the management of status dystonicus and prestatus dystonicus in children and adolescents, in order to examine clinical features, acute management, and risk of relapse in a paediatric cohort.

METHOD

Clinical, demographic, and therapeutic features were analysed according to disease severity. Risk of subsequent relapse was estimated through Kaplan-Meier curves.

RESULTS

Thirty-four patients (eight females, 26 males) experiencing 63 episodes of acute dystonia exacerbations at a tertiary referral Italian hospital were identified. Mean age at status dystonicus presentation was 9 years 11 months (11y at inclusion in the study). Onset of dystonia dated back to infancy in most cases. Fourteen patients experienced two or more episodes. Infections were the most common trigger (48%). Benzodiazepines were the most commonly used drugs for acute management. Stereotactic pallidotomy was performed in six cases during status dystonicus, and in two additional patients it was electively performed after medical management. The probability of survival free from status dystonicus relapses was 78% after 4 months and 61% after 27 months.

INTERPRETATION

Dystonia exacerbations are potentially life-threating emergencies, with a considerable risk of relapse. Nevertheless, no obvious factors for relapse risk stratification exist. Pallidotomy is a feasible option in medical refractory status dystonicus for patients with limited deep brain stimulation applicability, but the risk of recurrence is elevated.

WHAT THIS PAPER ADDS

Acute exacerbations may affect up to 10% of children with dystonia. Infections are the most common precipitant factor. In about 30% of the cases, intensive care unit admission is needed. Subsequent relapses are common, reaching 25% risk at 1 year. Pallidotomy can be considered in medical-refractory cases with no deep brain stimulation applicability.

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.

Clonidine in pediatric anesthesia: the new panacea or a drug still looking for an indication?

PURPOSE OF REVIEW

Clonidine, an α2-receptor agonist is a widely used drug in pediatrics with a large scope of indications ranging from prevention of postoperative emergence agitation, analgesia, anxiolysis, sedation, weaning to shivering. In the era of 'opioid-free' medicine with much attention be directed toward increasing problems with opioid use, clonidine due to its global availability, low cost and safety profile has become an even more interesting option.

RECENT FINDINGS

Increasing evidence from randomised clinical trials support the use of clonidine in healthy children in the perioperative setting. Clonidine appears to significantly reduce postoperative emergence agitation, opioid consumption, shivering, nausea and vomiting. In addition, emerging evidence support the use of clonidine for sedation of critically ill children in ICUs. In this review, the current evidence for clonidine in pediatrics is described and analyzed including a meta-analysis for prevention of emergence agitation.

SUMMARY

Clonidine appears a safe and beneficial drug with moderate to high-quality evidence supporting its use in pediatric anesthesia. However, for some indications and populations such as children younger than 12 months old and those with hemodynamic instability, there is an urgent need for high-quality trials.

Update on current and emerging therapies for dystonia

Treatment strategies for dystonia depend on the focal, segmental or generalized distribution of symptoms. Chemodenervation with botulinum toxin remains the treatment of choice for focal- or select-body regions in generalized and segmental dystonia. A potentially longer acting formulation of botulinum toxin is being investigated besides the currently available formulations. Electromyography increases toxin injection accuracy and may reduce injection number, frequency, side effects and costs by identifying dystonic muscle activity. Oral anticholinergics, baclofen and clonazepam are used off-label, but novel drugs in development include sodium oxybate, zonisamide and perampanel. Characterizing dystonia as a sensorimotor circuit disorder has prompted the use of noninvasive neuromodulation procedures. These techniques need further study but simultaneous rehabilitation techniques appear to also improve outcomes. Pallidal deep-brain stimulation is beneficial for medication-refractory primary generalized and possibly focal dystonia such as cervical dystonia. Certain genetic conditions are amenable to specific therapies and future gene-targeted therapies could benefit selected dystonia patients.

Current therapies and therapeutic decision making for childhood-onset movement disorders

Movement disorders differ in children to adults. First, neurodevelopmental movement disorders such as tics and stereotypies are more prevalent than parkinsonism, and second, there is a genomic revolution which is now explaining many early-onset dystonic syndromes. We outline an approach to children with movement disorders starting with defining the movement phenomenology, determining the level of functional impairment due to abnormal movements, and screening for comorbid psychiatric conditions and cognitive impairments which often contribute more to disability than the movements themselves. The rapid improvement in our understanding of the etiology of movement disorders has resulted in an increasing focus on precision medicine, targeting treatable conditions and defining modifiable disease processes. We profile some of the key disease-modifying therapies in metabolic, neurotransmitter, inflammatory, and autoimmune conditions and the increasing focus on gene or cellular therapies. When no disease-modifying therapies are possible, symptomatic therapies are often all that is available. These classically target dopaminergic, cholinergic, alpha-adrenergic, or GABAergic neurochemistry. Increasing interest in neuromodulation has highlighted that some clinical syndromes respond better to DBS, and further highlights the importance of "disease-specific" therapies with a future focus on individualized therapies according to the genomic findings or disease pathways that are disrupted. We summarize some pragmatic applications of symptomatic therapies, neuromodulation techniques, and some rehabilitative interventions and provide a contemporary overview of treatment in childhood-onset movement disorders. © 2019 International Parkinson and Movement Disorder Society.

Status dystonicus: a diagnosis delayed

Status dystonicus, also known as the dystonic storm or dystonic crisis, is rare but may prove fatal due to respiratory and bulbar complications. In adults, the condition is rare and possibly under-reported. The lack of awareness of this condition among emergency and acute physicians may lead to an incorrect or delayed diagnosis, which should be avoided. We report a case of a 23-year-old man with athetoid cerebral palsy who presented to a district general hospital with uncontrolled dystonic movements, which were diagnosed as status dystonicus. This was successfully treated with intravenous clonidine, with full recovery returning to baseline functional state.

Status dystonicus due to missense variant in ARX: Diagnosis and management

Movement disorders are increasingly identified in infantile encephalopathies due to single gene disorders (e.g. SCN2A, CDKL5, ARX). The associated movement disorder can be challenging to recognise and treat. We report a 2 year-old boy with a background history of Ohtahara syndrome due to a missense variant in ARX (the aristaless-related homeobox gene) who subsequently developed status dystonicus. ARX is a transcription factor that plays a critical role in cortical neuronal development and is associated with a range of important neurodevelopmental disorders depending on the site of the pathogenic variant. Cases of status dystonicus are described with variants affecting the polyalanine expansion region of ARX but have not been reported previously with variants affecting the aristaless domain of ARX as in this case. Dystonic episodes posed a challenge in recognition and treatment, including confusion with status epilepticus. We discuss the difficulties in diagnosis and management of status dystonicus, an underreported life-threatening emergency in children.

Deep brain stimulation treated dystonia-trajectory via status dystonicus

BACKGROUND

Status dystonicus (SD) is a life-threatening condition.

OBJECTIVE AND METHODS

In a dystonia cohort who developed status dystonicus, we analyzed demographics, background dystonia phenomenology and complexity, trajectory previous to-, via status dystonicus episodes, and evolution following them.

RESULTS

Over 20 years, 40 of 328 dystonia patients who were receiving DBS developed 58 status dystonicus episodes. Dystonia was of pediatric onset (95%), frequently complex, and had additional cognitive and pyramidal impairment (62%) and MRI alterations (82.5%); 40% of episodes occured in adults. Mean disease duration preceding status dystonicus was 10.3 ± 8 years. Evolution time to status dystonicus varied from days to weeks; however, 37.5% of patients exhibited progressive worsening over years. Overall, DBS was efficient in resolving 90% of episodes.

CONCLUSION

Status dystonicus is potentially reversible and a result of heterogeneous conditions with nonuniform underlying physiology. Recognition of the complex phenomenology, morphological alterations, and distinct patterns of evolution, before and after status dystonicus, will help our understanding of these conditions. © 2018 International Parkinson and Movement Disorder Society.

Management of Pediatric Movement Disorders: Present and Future

Management of movement disorders in children is an evolving field. This article outlines the major categories of treatment options for pediatric movement disorders and general guidelines for their use. We review the evidence for existing therapies, which continue to lack large-scale controlled trials to guide treatment decisions. The field continues to rely on extrapolations from adult studies and lower quality evidence such as case reports and case series to guide treatment guidelines and consensus statements. Developments in new pharmaceuticals for rare diseases have begun to provide hope for those cases in which a genetic diagnosis can be made. Advances in surgical therapies such as deep brain stimulation as well as new modes of treatment such as gene therapy, epigenetic modulation, and stem cell therapy hold promise for improving outcomes in both primary and secondary causes of movement disorders. There is a critical need for larger, multicenter, controlled clinical trials to fully evaluate treatments for pediatric movement disorders.

Pharmacological and neurosurgical interventions for managing dystonia in cerebral palsy: a systematic review

AIM

To systematically review evidence for pharmacological/neurosurgical interventions for managing dystonia in individuals with cerebral palsy (CP) to inform a care pathway.

METHOD

Searches included studies with a minimum of five participants with dystonia in CP receiving oral baclofen, benzodiazepines (clonazepam, diazepam, lorazepam), clonidine, gabapentin, levodopa, trihexyphenidyl, botulinum toxin, intrathecal baclofen (ITB), or deep brain stimulation (DBS). Evidence was classified according to American Academy of Neurology guidelines.

RESULTS

Twenty-eight articles underwent data extraction: one levodopa, five trihexyphenidyl, three botulinum toxin, six ITB, and 13 DBS studies. No articles for oral baclofen, benzodiazepines, clonidine, or gabapentin met the inclusion criteria. Evidence for reducing dystonia was level C (possibly effective) for ITB and DBS; level C (possibly ineffective) for trihexyphenidyl; and level U (inadequate data) for botulinum toxin.

INTERPRETATION

For dystonia reduction, ITB and DBS are possibly effective, whereas trihexyphenidyl was possibly ineffective. There is insufficient evidence to support oral medications or botulinum toxin to reduce dystonia. There is insufficient evidence for pharmacological and neurosurgical interventions to improve motor function, decrease pain, and ease caregiving. The majority of the pharmacological and neurosurgical management of dystonia in CP is based on clinical expert opinion.

WHAT THIS PAPER ADDS

Intrathecal baclofen and deep brain stimulation are possibly effective in reducing dystonia. Current evidence does not support effectiveness of oral medications or botulinum toxin to reduce dystonia. Evidence is inadequate for pharmacological/neurosurgical interventions impact on improving motor function, pain/comfort, and easing caregiving. The majority of the care pathway rests on expert opinion.