Movement disorders of probable infectious origin

Definition, diagnosis and classification of infection-related movement disorders: Consensus proposal

BACKGROUND

Infection-related movement disorders (IRMD) present a complex diagnostic challenge due to the broad phenotypic spectrum, the variety of possible infectious aetiologies, and the complicated underlying mechanisms. Yet, a comprehensive framework for classifying IRMD is lacking.

METHODS

An international consensus panel under the directives of the Movement Disorders Society Infection-Related Movement Disorders Study Group developed a comprehensive definition and a consensus classification system. Case scenarios were used for validation.

RESULTS

A definition for IRMD and a two-axis-based classification system consisting of six descriptors are proposed, intended as tools for researchers and clinicians. Collected information on clinical characteristics, investigational findings, the infectious organism and presumed pathogenesis facilitate the evaluation of diagnostic certainty.

CONCLUSION

The proposed framework will serve for optimised diagnostic algorithms, systematic aggregation of informative datasets across studies, and ultimately improved care and outcome of patients with IRMDs.

Overview of management of infection-related movement disorders with focus on specific-infections

Infections are important treatable causes of secondary movement disorders (MD) that can have heterogeneous presentations. According to various studies, infection-related movement disorders (IRMD) account for around 10-20% of secondary MD. Certain infections have a predilection for causing various MD, and some MD phenomenologies, such as acute cerebellar ataxia and opsoclonus-myoclonus-ataxia syndromes (OMAS), suggest a strong possibility of an underlying infectious cause. The underlying pathophysiology is multifaceted, including direct neuronal damage due to neurotropism, granulomas, abscesses causing structural damage, and inflammatory and autoimmune responses triggered by infections. Understanding the prevalence, spectrum, and pattern of these IRMD and common infections that are responsible helps in early diagnosis, and instituting appropriate, timely treatment, thereby improving the overall prognosis and avoiding unnecessary investigations. In this review, we aim to provide a brief overview of common infections associated with MD, common clinical presentations of IRMD, their underlying pathophysiology, and overall approach to their treatment, with a focus on specific treatments of prevalent and treatable IRMD.

Chorea following SARS-CoV-2 infection and vaccination: a systematic review of reported cases

OBJECTIVES

Chorea following SARS-CoV-2 infection and vaccination, has been increasingly recognized. We aimed to synthesize clinical and paraclinical characteristics, treatment responses, and outcomes of this neurologic complication.

METHODS

We systematically reviewed LitCOVID, the World Health Organization database on COVID-19, and MedRxiv up to March 2023, following a published protocol.

RESULTS

We included 14 chorea cases in patients with SARS-CoV-2 infection and eight following COVID-19 vaccination. Acute or subacute chorea preceded COVID-19 symptoms within 1-3 days or developed up to 3 months after infection. Frequently it was generalized (85.7%), with associated neurological manifestations (encephalopathy 35.7%; other movement disorders 7.1%). After vaccination, chorea had a sudden onset (87.5%) within 2 weeks (75%); 87.5% of cases presented hemichorea, with hemiballismus (37.5%) or other movement disorders; 12.5% presented additional neurological findings. Cerebrospinal fluid was normal in 50% of infected individuals but abnormal in all vaccinated cases. Brain magnetic resonance imaging detected normal basal ganglia in 51.7% of infection cases and 87.5% following vaccination.

CONCLUSION

In SARS-CoV-2 infection, chorea may present several pathogenic mechanisms: autoimmune response to infection, direct infection-related injury, or an infection-related complication (i.e., acute disseminated encephalomyelitis, cerebral venous sinus thrombosis, hyperglycemia); also, previous Sydenham chorea may relapse. After COVID-19 vaccination, chorea could be due to an autoimmune reaction or other mechanisms (vaccine-induced hyperglycemia, stroke).

A novel diagnostic approach for patients with adult-onset dystonia

Adult-onset dystonia can be acquired, inherited or idiopathic. The dystonia is usually focal or segmental and for a limited number of cases causal treatment is available. In recent years, rapid developments in neuroimmunology have led to increased knowledge on autoantibody-related dystonias. At the same time, genetic diagnostics in sequencing technology have evolved and revealed several new genes associated with adult-onset dystonia. Furthermore, new phenotype-genotype correlations have been elucidated. Consequently, clinicians face the dilemma of which additional investigations should be performed and whether to perform genetic testing or not. To ensure early diagnosis and to prevent unnecessary investigations, integration of new diagnostic strategies is needed.We designed a new five-step diagnostic approach for adult-onset dystonia. The first four steps are based on a broad literature search and expert opinion, the fifth step, on when to perform genetic testing, is based on a detailed systematic literature review up to 1 December 2021.The basic principle of the algorithm is that genetic testing is unlikely to lead to changes in management in three groups: (1) patients with an acquired form of adult-onset dystonia; (2) patients with neurodegenerative disorders, presenting with a combined movement disorder including dystonic symptoms and (3) patients with adult-onset isolated focal or segmental dystonia. Throughout the approach, focus lies on early identification of treatable forms of dystonia, either acquired or genetic.This novel diagnostic approach for adult-onset dystonia can help clinicians to decide when to perform additional tests, including genetic testing and facilitates early aetiological diagnosis, to enable timely treatment.

Movement Disorders Induced by SARS-CoV-2 Infection: Protocol for a Scoping Review

Infections are a significant cause of movement disorders. The clinical manifestations of SARS-CoV-2 infection are variable, with up to one-third of patients developing neurologic complications, including movement disorders. This scoping review will lay out a comprehensive understanding of movement disorders induced by SARS-CoV-2 infection. We aim to investigate the epidemiology, clinical and paraclinical features, interventions, and diagnostic challenges in patients with different types of movement disorders in the context of SARS-CoV-2 infection. We will search three databases applying appropriate search terms. Inclusion and exclusion criteria are pre-defined; the data of eligible studies will be extracted in standardized forms. We will report the results following Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). We will present information for clinicians and other healthcare professionals, policymakers, and public health researchers. In addition, the results of the present review may assist in the development and confirmation of inclusion criteria and research questions for further systematic review or meta-analysis, with more precise, narrower questions.

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.

Metoclopramide-Induced Acute Dystonia: Data From a Pediatric Emergency Unit

OBJECTIVES

Metoclopramide is a commonly used medication in pediatric practice, and dystonia is a common adverse effect of it. The present study aims to evaluate the clinical characteristics of metoclopramide-induced acute dystonic reactions (MIADRs) in pediatric patients admitted to the pediatric emergency unit.

METHODS

Twenty-eight patients were admitted with MIADRs between June 2004 and April 2016; they were enrolled into the study retrospectively.

RESULTS

The study group was composed of 13 females and 15 males with the mean ± SD age of the females higher than that of the males, 12.3 ± 4.5 and 7.8 ± 4.3 years, respectively. Only 9 (32.1%) of the patients were diagnosed as MIADRs at the time of admission. Seventeen patients (60.7%) received over the recommended daily dose of metoclopramide. Dystonia was focal in most of the patients, with the most affected parts consisting of the neck, eyes, and orolingual regions. In 9 of the patients, the dystonia was episodic in nature. Pharmacological treatment was used for 18 patients. No patients died, and none suffered long-term injury related to MIADRs.

CONCLUSIONS

Metoclopramide administration may be associated with the occurrence of acute dystonic reaction. Metoclopramide-induced acute dystonic reactions may be misdiagnosed, so detailed medical history gathering and a high index of suspicion are warranted. Our data suggest that MIADRs may be dose related and that there may be age- and sex-related differences in the epidemiology of MIADRs.

Clinical conundrum: status epilepticus culminating into acute dystonia myoclonus

A 7-year-old child who suffered from symptomatic focal epilepsy as a sequel to perinatal hypoxia used to have frequent seizures. This time she developed prolonged status epilepticus lasting for over 5 hours. She received a treatment in the form of intravenous midazolam and reinitiation of sodium valproate and clobazam that were discontinued previously. Seizures were controlled over a couple of hours, but she remained unresponsive. Later, she developed acute onset dystonia (day 3 post-status epilepticus) and also myoclonic jerks. She presented to us after 3 weeks of onset of these complaints and we considered hypoxic encephalopathy resulting from prolonged status epilepticus or acute encephalitis or non-convulsive status epilepticus. However, acute onset dystonia and periodicity of myoclonic jerks were pointers against it, and on evaluation, she was diagnosed with atypical fulminant subacute sclerosing panencephalitis (SSPE). Knowing the atypical presentations of SSPE is important in planning management and prognostication.