A Critical Examination of the Clinical Diagnosis of Functional Tic-like Behaviors.

BACKGROUND: Since the COVID-19 pandemic, movement disorder clinics have seen an increase in patients with an unusual type of tic-like symptoms: young adults with abrupt onset complex behaviors. It was quickly suspected that these patients suffered from functional neurological symptoms, later named Functional Tic-Like Behaviors (FTLB). Subsequent research on the differential diagnosis between FTLB and tics has been substantial and led to the development of diagnostic checklists. OBJECTIVES: We conducted a theoretical reappraisal of the FTLB literature to clarify the validity of the concept and its diagnostic implications. METHODS: This paper addresses several key aspects of the current FTLB literature: circular reasoning, the complications of the FTLB phenomenology and demographics, the impact of FTLB on tic literature at large, and issues with alignment of the FTLB concept with the diagnostic criteria for functional disorders. RESULTS: The clinical approach to FTLB might involve circular reasoning due to a lack of clinical benchmarks. The FTLB phenomenology and demographics may need more work to ensure a lack of bias and a proper description of this patient group including a clear distinction from tics. The impact of the FTLB discussion on the wider literature needs consideration. The validation of positive signs may help with both these endeavors and pave way to the inclusion of FTLB within psychiatric classification systems. Furthermore, the coexistence of FTLB and tics within the same patient needs to be addressed. CONCLUSION: More research may be needed to fully establish the diagnosis of FTLB and differentiate it from tics.

Intense Imagery Movements May Lead to Maladaptive Daydreaming: A Case Series and Literature Review.

BACKGROUND: This case series highlights the connection between childhood intense imagery movements (IIM) and adult-reported maladaptive daydreaming (MD). Motor stereotypies occur in typically developing children and also with co-occurring neurodevelopmental differences. A subgroup with complex motor stereotypies reports accompanying intense imagery, often enhanced by the movements. This phenomenon can persist into adulthood and, in some cases, will need active management to prevent significant distress and impairment. CASES: Six adults, self-reporting maladaptive daydreaming associated with stereotypies, are presented to demonstrate the associations. LITERATURE REVIEW: The clinical significance and function of IIM and MD are unclear, but several hypotheses are discussed, including the mechanism of emotional regulation through sensory seeking, as a process for processing childhood psychological trauma, as intrusive thoughts or images as part of a subtype of Obsessive Compulsive Disorder, or as a result of diverse attentional networks seen in neurodevelopmental disorders. CONCLUSIONS: This paper highlights important connections between IIM and MD. Many adults with MD show a childhood origin of stereotypical movements. Whilst immersive daydreaming may provide creativity and emotional regulation, there is evidence of distress and impairment of function for some adults, leading to MD diagnoses. Recognizing this phenomenon is important for all neurologists and physicians working with stereotypical movements.

An investigation into mothers' experiences of their children's functional tic-like behaviour and tic attacks.

OBJECTIVE: This is the first study to systematically explore the lived experiences of sudden and new onset of severe functional tics from the perspective of the mother's experiences and describes their attempts to access support services in the United Kingdom. METHOD: Twenty-One mothers of young people aged between 12 to 17 years with functional tic-like behaviour (FTLB) took part in semi-structured interviews. Thematic analysis of the transcribed interviews revealed gaps and inconsistencies within the process of gaining access to professional services and a lack of support for the management of tics and functional tic-like movements, in addition to highlighting the impact it had on daily family life. RESULTS: The themes generated included the occurrence and development of tics, the severity and intensity of symptoms, the psychological impact on the family and the need to make recommendations for a clear care pathway. Managing the impact of the FTLB and co-occurring conditions such as suicidal ideation and self-harm, as well as the physical and emotional trauma, commonly contributed to feelings of isolation and helplessness, which impacted negatively on the family's ability to function and participate in society. CONCLUSIONS: The findings emphasize the urgent need to create a clear management pathway for those experiencing FTLB, including the need for more professionals with relevant knowledge, to improve the dialogue with families during the referral process, whilst prioritising the treatment of anxiety and other identified mental health concerns.

Genome-wide Association Study Points to Novel Locus for Gilles de la Tourette Syndrome.

BACKGROUND: Tourette syndrome (TS) is a childhood-onset neurodevelopmental disorder of complex genetic architecture and is characterized by multiple motor tics and at least one vocal tic persisting for more than 1 year. METHODS: We performed a genome-wide meta-analysis integrating a novel TS cohort with previously published data, resulting in a sample size of 6133 individuals with TS and 13,565 ancestry-matched control participants. RESULTS: We identified a genome-wide significant locus on chromosome 5q15. Integration of expression quantitative trait locus, Hi-C (high-throughput chromosome conformation capture), and genome-wide association study data implicated the NR2F1 gene and associated long noncoding RNAs within the 5q15 locus. Heritability partitioning identified statistically significant enrichment in brain tissue histone marks, while polygenic risk scoring of brain volume data identified statistically significant associations with right and left thalamus volumes and right putamen volume. CONCLUSIONS: Our work presents novel insights into the neurobiology of TS, thereby opening up new directions for future studies.

Polygenic risk score-based phenome-wide association study identifies novel associations for Tourette syndrome.

Tourette Syndrome (TS) is a complex neurodevelopmental disorder characterized by vocal and motor tics lasting more than a year. It is highly polygenic in nature with both rare and common previously associated variants. Epidemiological studies have shown TS to be correlated with other phenotypes, but large-scale phenome wide analyses in biobank level data have not been performed to date. In this study, we used the summary statistics from the latest meta-analysis of TS to calculate the polygenic risk score (PRS) of individuals in the UK Biobank data and applied a Phenome Wide Association Study (PheWAS) approach to determine the association of disease risk with a wide range of phenotypes. A total of 57 traits were found to be significantly associated with TS polygenic risk, including multiple psychosocial factors and mental health conditions such as anxiety disorder and depression. Additional associations were observed with complex non-psychiatric disorders such as Type 2 diabetes, heart palpitations, and respiratory conditions. Cross-disorder comparisons of phenotypic associations with genetic risk for other childhood-onset disorders (e.g.: attention deficit hyperactivity disorder [ADHD], autism spectrum disorder [ASD], and obsessive-compulsive disorder [OCD]) indicated an overlap in associations between TS and these disorders. ADHD and ASD had a similar direction of effect with TS while OCD had an opposite direction of effect for all traits except mental health factors. Sex-specific PheWAS analysis identified differences in the associations with TS genetic risk between males and females. Type 2 diabetes and heart palpitations were significantly associated with TS risk in males but not in females, whereas diseases of the respiratory system were associated with TS risk in females but not in males. This analysis provides further evidence of shared genetic and phenotypic architecture of different complex disorders.

European Society for the Study of Tourette Syndrome 2022 criteria for clinical diagnosis of functional tic-like behaviours: International consensus from experts in tic disorders.

BACKGROUND AND PURPOSE: In 2020, health professionals witnessed a dramatic increase in referrals of young people with rapid onset of severe tic-like behaviours. We assembled a working group to develop criteria for the clinical diagnosis of functional tic-like behaviours (FTLBs) to help neurologists, pediatricians, psychiatrists, and psychologists recognize and diagnose this condition. METHODS: We used a formal consensus development process, using a multiround, web-based Delphi survey. The survey was based on an in-person discussion at the European Society for the Study of Tourette Syndrome (ESSTS) meeting in Lausanne in June 2022. Members of an invited group with extensive clinical experience working with patients with Tourette syndrome and FTLBs discussed potential clinical criteria for diagnosis of FTLBs. An initial set of criteria were developed based on common clinical experiences and review of the literature on FTLBs and revised through iterative discussions, resulting in the survey items for voting. RESULTS: In total, 24 members of the working group were invited to participate in the Delphi process. We propose that there are three major criteria and two minor criteria to support the clinical diagnosis of FTLBs. A clinically definite diagnosis of FTLBs can be confirmed by the presence of all three major criteria. A clinically probable diagnosis of FTLBs can be confirmed by the presence of two major criteria and one minor criterion. CONCLUSIONS: Distinguishing FTLBs from primary tics is important due to the distinct treatment paths required for these two conditions. A limitation of the ESSTS 2022 criteria is that they lack prospective testing of their sensitivity and specificity.

Clinical Reasoning: A Teenage Girl With Progressive Hyperkinetic Movements, Seizures, and Encephalopathy.

The "epilepsy-dyskinesia" spectrum is increasingly recognized in neurogenetic and neurometabolic conditions. It can be challenging to diagnose because of clinical and genetic heterogeneity, atypical or nonspecific presentations, and the rarity of each diagnostic entity. This is further complicated by the lack of sensitive or specific biomarkers for most nonenzymatic neurometabolic conditions. Nevertheless, clinical awareness and timely diagnosis are paramount to facilitate appropriate prognostication, counseling, and management.This report describes a case of a teenage girl who had presented at 14 months with a protracted illness manifesting as gastrointestinal upset and associated motor and cognitive regression. A choreoathetoid movement disorder, truncal ataxia, and microcephaly evolved after the acute phase. Neurometabolic and inflammatory investigations, EEG, brain MRI, muscle biopsy (including respiratory chain enzyme studies), and targeted genetic testing were unremarkable. A second distinct regression phase ensued at 14 years consisting of encephalopathy, multifocal motor seizures, absent deep tendon reflexes and worsening movements, gut dysmotility, and dysphagia. Video EEGs showed an evolving developmental and epileptic encephalopathy with multifocal seizures and nonepileptic movements. MRI of the brain revealed evolving and fluctuating patchy bihemispheric cortical changes, cerebellar atrophy with signal change, mild generalized brain volume loss, and abnormal lactate on MR spectroscopy. The article discusses the differential diagnostic approach and management options for patients presenting with neurologic regression, encephalopathy, seizures, and hyperkinetic movements. It also emphasizes the utility of next-generation sequencing in providing a rapid, efficient, cost-effective way of determining the underlying etiology of complex neurologic presentations.

The spectrum of functional tic-like behaviours: Data from an international registry.

BACKGROUND AND PURPOSE: Between 2019 and 2022, there was a marked rise in adolescents/young adults seeking urgent help for functional tic-like behaviours (FTLBs). Given the global scale of this phenomenon, we aimed to pool cases from different institutions in an international registry to better characterize this spectrum and facilitate future longitudinal observation. METHODS: An international collaborative group from 10 tertiary referral centres for tic disorders collected retrospective data on FTLB patients who sought specialists' attention between the last quarter of 2019 and June 2022. An audit procedure was used for collection of data, which comprised demographics, course of presentation and duration, precipitating and predisposing factors, phenomenology, comorbidities, and pharmacological treatment outcome. RESULTS: During the study period, we collected data on 294 patients with FTLBs, 97% of whom were adolescents and young adults and 87% of whom were female. FTLBs were found to have a peak of severity within 1 month in 70% of patients, with spontaneous remissions in 20%, and a very high frequency of complex movements (85%) and vocalizations (81%). Less than one-fifth of patients had pre-existing primary tic disorder, 66% had comorbid anxiety disorders, 28% comorbid depressive disorders, 24% autism spectrum disorder and 23% attention deficit/hyperactivity disorder. Almost 60% explicitly reported exposure to tic-related social media content. The vast majority of pharmacologically treated patients did not report benefit with tic-suppressing medications. CONCLUSIONS: Our data from the largest multicentre registry of FTLBs to date confirm substantial clinical differences from primary tic disorders. Social modelling was the most relevant contributing factor during the pandemic. Future longitudinal analyses from this database may help understand treatment approaches and responsiveness.

Case report: Advice for schools on managing functional tic-like behaviours.

There has been an increase in the occurrence of sudden onset functional tic-like behaviours in adolescents during the COVID-19 pandemic, which has had a significant impact on the affected individual's ability to engage with education. The aim of this article is to generate discussion and inform practice within schools with regard to the management of functional tic-like behaviours. An advice sheet for schools has been produced based on clinical expertise and experience of consulting with schools around the management within education settings. Case examples are presented highlighting the importance and impact of these strategies. We also highlight the need for further evaluation of the effectiveness of the advice sheet in collaboration with schools and families.

The changing landscape of childhood tic disorders following COVID-19.

The article describes classification, aetiology and features of typical tic disorders (Tourette syndrome) and their management with an additional focus on a surge in atypical tic presentations following the COVID-19 pandemic, often described as functional tics, or functional tic-like movements. We discuss what explains their atypical nature and what might underpin this increase in incidence. Lastly the article provides an overview of management of functional tics, so readers can understand how management of these differs from typical tic disorders.

Lack of Association of Group A Streptococcal Infections and Onset of Tics: European Multicenter Tics in Children Study.

BACKGROUND AND OBJECTIVES: The goal of this work was to investigate the association between group A streptococcal (GAS) infections and tic incidence among unaffected children with a family history of chronic tic disorders (CTDs). METHODS: In a prospective cohort study, children with no history for tics who were 3 to 10 years of age with a first-degree relative with a CTD were recruited from the European Multicentre Tics in Children Study (EMTICS) across 16 European centers. Presence of GAS infection was assessed with throat swabs, serum anti-streptolysin O titers, and anti-DNAse titers blinded to clinical status. GAS exposure was defined with 4 different definitions based on these parameters. Cox regression analyses with time-varying GAS exposure were conducted to examine the association of onset of tics and GAS exposure during follow-up. Sensitivity analyses were conducted with Cox regression and logistic regression analyses. RESULTS: A total of 259 children were recruited; 1 child was found to have tic onset before study entry and therefore was excluded. Sixty-one children (23.6%) developed tics over an average follow-up period of 1 (SD 0.7) year. There was a strong association of sex and onset of tics, with girls having an ≈60% lower risk of developing tics compared to boys (hazard ratio [HR] 0.4, 95% confidence interval [CI] 0.2-0.7). However, there was no statistical evidence to suggest an association of any of the 4 GAS exposure definitions with tic onset (GAS exposure definition 1: HR 0.310, 95% CI 0.037-2.590; definition 2: HR 0.561, 95% CI 0.219-1.436; definition 3: HR 0.853, 95% CI 0.466-1.561; definition 4: HR 0.725, 95% CI 0.384-1.370). DISCUSSION: These results do not suggest an association between GAS exposure and development of tics. CLASSIFICATION OF EVIDENCE: This study provides Class I evidence that group A streptococcal exposure does not associate with the development of tics in children with first-degree relatives with chronic tic disorder.

Paediatric tic-like presentations during the COVID-19 pandemic.

BACKGROUND AND AIM: Clinical centres have seen an increase in tic-like movements during the COVID-19 pandemic. A series of children and adolescents are described. METHODS: A retrospective chart review of 34 consecutive paediatric patients presenting with sudden onset tic-like movements, seen over 6 months. RESULTS: 94% of patients were female, with an average age of sudden onset or increase of tic-like movements of 13.7 years. 44% had a previous diagnosis of tics, and 47% initially presented to an emergency department. Comorbid psychiatric and neurodevelopmental disorders were reported in 91% with 68% reporting anxiety. CONCLUSION: We highlight a dramatic presentation of sudden onset functional tic-like movements in predominantly female adolescents to help inform identification and management. There is need to research the neurobiological underpinnings and environmental exacerbating factors leading to these presentations and to explore effective therapeutic strategies.

European clinical guidelines for Tourette syndrome and other tic disorders-version 2.0. Part I: assessment.

In 2011 a working group of the European Society for the Study of Tourette Syndrome (ESSTS) has developed the first European assessment guidelines for Tourette syndrome (TS). Now, we present an updated version 2.0 of these European clinical guidelines for Tourette syndrome and other tic disorders, part I: assessment. Therefore, the available literature has been thoroughly screened, supplemented with national guidelines across countries and discussions among ESSTS experts. Diagnostic changes between DSM-IV and DSM-5 classifications were taken into account and new information has been added regarding differential diagnoses, with an emphasis on functional movement disorders in both children and adults. Further, recommendations regarding rating scales to evaluate tics, comorbidities, and neuropsychological status are provided. Finally, results from a recently performed survey among ESSTS members on assessment in TS are described. We acknowledge that the Yale Global Tic Severity Scale (YGTSS) is still the gold standard for assessing tics. Recommendations are provided for scales for the assessment of tics and psychiatric comorbidities in patients with TS not only in routine clinical practice, but also in the context of clinical research. Furthermore, assessments supporting the differential diagnosis process are given as well as tests to analyse cognitive abilities, emotional functions and motor skills.

Clinical management of complex motor stereotypies.

This paper will review complex motor stereotypies and provide a summary of the current proposed treatment pathway.

Investigation of gene-environment interactions in relation to tic severity.

Tourette syndrome (TS) is a neuropsychiatric disorder with involvement of genetic and environmental factors. We investigated genetic loci previously implicated in Tourette syndrome and associated disorders in interaction with pre- and perinatal adversity in relation to tic severity using a case-only (N = 518) design. We assessed 98 single-nucleotide polymorphisms (SNPs) selected from (I) top SNPs from genome-wide association studies (GWASs) of TS; (II) top SNPs from GWASs of obsessive-compulsive disorder (OCD), attention-deficit/hyperactivity disorder (ADHD), and autism spectrum disorder (ASD); (III) SNPs previously implicated in candidate-gene studies of TS; (IV) SNPs previously implicated in OCD or ASD; and (V) tagging SNPs in neurotransmitter-related candidate genes. Linear regression models were used to examine the main effects of the SNPs on tic severity, and the interaction effect of these SNPs with a cumulative pre- and perinatal adversity score. Replication was sought for SNPs that met the threshold of significance (after correcting for multiple testing) in a replication sample (N = 678). One SNP (rs7123010), previously implicated in a TS meta-analysis, was significantly related to higher tic severity. We found a gene-environment interaction for rs6539267, another top TS GWAS SNP. These findings were not independently replicated. Our study highlights the future potential of TS GWAS top hits in gene-environment studies.

Systemic Inflammation Is Associated With Neurologic Involvement in Pediatric Inflammatory Multisystem Syndrome Associated With SARS-CoV-2.

OBJECTIVE: Pediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS) is a severe immune-mediated disorder. We aim to report the neurologic features of children with PIMS-TS. METHODS: We identified children presenting to a large children's hospital with PIMS-TS from March to June 2020 and performed a retrospective medical note review, identifying clinical and investigative features alongside short-term outcome of children presenting with neurologic symptoms. RESULTS: Seventy-five patients with PIMS-TS were identified, 9 (12%) had neurologic involvement: altered conciseness (3), behavioral changes (3), focal neurology deficits (2), persistent headaches (2), hallucinations (2), excessive sleepiness (1), and new-onset focal seizures (1). Four patients had cranial images abnormalities. At 3-month follow-up, 1 child had died, 1 had hemiparesis, 3 had behavioral changes, and 4 completely recovered. Systemic inflammatory and prothrombotic markers were higher in patients with neurologic involvement (mean highest CRP 267 vs 202 mg/L, p = 0.05; procalcitonin 30.65 vs 13.11 µg/L, p = 0.04; fibrinogen 7.04 vs 6.17 g/L, p = 0.07; d-dimers 19.68 vs 7.35 mg/L, p = 0.005). Among patients with neurologic involvement, these markers were higher in those without full recovery at 3 months (ferritin 2284 vs 283 µg/L, p = 0.05; d-dimers 30.34 vs 6.37 mg/L, p = 0.04). Patients with and without neurologic involvement shared similar risk factors for PIMS-TS (Black, Asian and Minority Ethnic ethnicity 78% vs 70%, obese/overweight 56% vs 42%). CONCLUSIONS: Broad neurologic features were found in 12% patients with PIMS-TS. By 3-month follow-up, half of these surviving children had recovered fully without neurologic impairment. Significantly higher systemic inflammatory markers were identified in children with neurologic involvement and in those who had not recovered fully.