Diagnostic approach to paediatric movement disorders: a clinical practice guide

Abstract

Paediatric movement disorders (PMDs) comprise a large group of disorders (tics, myoclonus, tremor, dystonia, chorea, Parkinsonism, ataxia), often with mixed phenotypes. Determination of the underlying aetiology can be difficult given the broad differential diagnosis and the complexity of the genotype–phenotype relationships. This can make the diagnostic process time‐consuming and difficult. In this overview, we present a diagnostic approach for PMDs, with emphasis on genetic causes. This approach can serve as a framework to lead the clinician through the diagnostic process in eight consecutive steps, including recognition of the different movement disorders, identification of a clinical syndrome, consideration of acquired causes, genetic testing including next‐generation sequencing, post‐sequencing phenotyping, and interpretation of test results. The aim of this approach is to increase the recognition and diagnostic yield in PMDs. What this paper adds An up‐to‐date description and diagnostic framework for testing of paediatric movement disorders is presented. The framework helps to determine which patients will benefit from next‐generation sequencing.

Movement disorders in patients with Rett syndrome: A systematic review of evidence and associated clinical considerations

“…Movement disorders can emerge with different clinical phenotypes spanning across dystonia, Parkinsonism, bruxism, spasticity, tremor, and ataxia. While there is useful information on clinical practices for managing pediatric movement disorders, 60 improved diagnostics for dystonia , 61 and guidance on the management of stereotypies, 62 , 63 there is little information on the treatment of movement disorders. In the following section, general treatments for movement disorders and their implications for patients with RTT will be discussed.…”

Acute Movement Disorders in Childhood

“…As a result, no diagnostic algorithm may be applied to acute-onset MDs from birth to adolescence. Nevertheless, as previously described for chronic MDs [ 10 ], some general rules can be useful to build a rigorous but practical approach and can be applied with some differences to acute-onset MDs ( Figure 1 ) [ 10 ]. The definition of the prominent MD phenomenology in the setting of a specific clinical syndrome is the paradigm according to which further investigations (if necessary) are considered, always prioritizing potentially treatable causes.…”

“…First, functional MDs often present with abrupt and dramatic onset [ 233 ]. Second, symptoms and their severity tend to vary, and disability is often selective or inconsistent [ 10 , 233 ]. Distractibility (namely, the disappearance or reduction in the severity of the symptoms when the patient is unobserved or distracted by a cognitive task) is a strong argument in favor of a functional etiology.…”

“…Distractibility (namely, the disappearance or reduction in the severity of the symptoms when the patient is unobserved or distracted by a cognitive task) is a strong argument in favor of a functional etiology. Similarly, the entrainment phenomenon can be actively searched in tremor and myoclonus: it consists in the synchronization of the involuntary movement to an externally imposed rhythm, and strongly suggests a functional MD [ 10 ]. In addition, several features can make functional phenomenology incongruent with an organic origin.…”

“…Despite these positive features, sometimes, functional MDs can be difficult to diagnose and both functional and organic MDs may coexist in the same patient [ 10 ].…”