The Phenomenology of Tics and Tic-Like Behavior in TikTok.

BACKGROUND: Pediatricians and pediatric subspecialists worldwide have reported a marked increase in functional (conversion) disorders with tic-like behaviors during the COVID-19 pandemic. These patients often report frequent viewing of Tourette syndrome (TS) TikTok videos, suggesting disease modeling. We aimed to evaluate tic phenomenology in videos posted on TikTok. METHODS: The 100 most-viewed videos under #tourettes in TikTok were randomly assigned to two of three primary reviewers (<2 years independent practice), all pediatric neurologists specializing in movement disorders, for extraction and classification of tic phenomenology. Initial disagreements were solved by consensus. If not resolved, one of five senior reviewers (>2 years independent pediatric movement disorder practice) served as a tiebreaker. In addition, two primary and one senior reviewer rated each video on a Likert scale from 1 = "All the tics are typical of TS" to 5 = "None of the tics are typical of TS". Median scores and Spearman correlation between primary and senior reviewers were calculated. RESULTS: Six videos without tic-like behaviors were excluded. Most videos depicted coprophenomena (coprolalia: 53.2%; copropraxia: 20.2%), often with unusual characteristics. Frequently, videos demonstrated atypical phenomenology such as very strong influence by the environment (motor: 54.3%; phonic: 54.3%), aggression (19.1%), throwing objects (22.3%), self-injurious behaviors (27.7%), and long phrases (>3 words; 45.7%). Most videos portrayed atypical, nontic behaviors (median [IQR] Likert ratings: 5 [4-5]). Primary vs. senior rater scores demonstrated moderate agreement (r = 0.46; P < 0.001). CONCLUSIONS: TS symptom portrayals on highly viewed TikTok videos are predominantly not representative or typical of TS.

Redefining the Pediatric Phenotype of X-Linked Monocarboxylate Transporter 8 (MCT8) Deficiency: Implications for Diagnosis and Therapies.

X-linked monocarboxylate transporter 8 (MCT8) deficiency results from a loss-of-function mutation in the monocarboxylate transporter 8 gene, located on chromosome Xq13.2 (Allan-Herndon-Dudley syndrome). Affected boys present early in life with neurodevelopment delays but have pleasant dispositions and commonly have elevated serum triiodothyronine. They also have marked axial hypotonia and quadriparesis but surprisingly little spasticity early in their disease course. They do, however, have subtle involuntary movements, most often dystonia. The combination of hypotonia and dystonia presents a neurorehabilitation challenge and explains why spasticity-directed therapies have commonly produced suboptimal responses. Our aim was to better define the spectrum of motor disability and to elucidate the neuroanatomic basis of the motor impairments seen in MCT8 deficiency using clinical observation and brain magnetic resonance imaging (MRI) in a cohort of 6 affected pediatric patients. Our findings identified potential imaging biomarkers and suggest that rehabilitation efforts targeting dystonia may be more beneficial than those targeting spasticity in the prepubertal pediatric MCT8 deficiency population.

Family history in juvenile Huntington disease: do the signs point to "yes" or "very doubtful"?

Juvenile Huntington disease (JHD)-Huntington disease (HD) with an onset ≤20 years-accounts for approximately 10% of all HD cases. Like the adult form of the disorder, JHD is a hereditary neurodegenerative disease characterized by dementia and behavioral changes, caused by an expanded CAG repeat within the first exon of the huntingtin (HTT) gene on chromosome 4.(1) Unlike the adult form, JHD tends to present with a rigid-dystonic picture or nonspecific motor and neuropsychological signs rather than chorea.(2,3.)

Definition and classification of hyperkinetic movements in childhood.

Hyperkinetic movements are unwanted or excess movements that are frequently seen in children with neurologic disorders. They are an important clinical finding with significant implications for diagnosis and treatment. However, the lack of agreement on standard terminology and definitions interferes with clinical treatment and research. We describe definitions of dystonia, chorea, athetosis, myoclonus, tremor, tics, and stereotypies that arose from a consensus meeting in June 2008 of specialists from different clinical and basic science fields. Dystonia is a movement disorder in which involuntary sustained or intermittent muscle contractions cause twisting and repetitive movements, abnormal postures, or both. Chorea is an ongoing random-appearing sequence of one or more discrete involuntary movements or movement fragments. Athetosis is a slow, continuous, involuntary writhing movement that prevents maintenance of a stable posture. Myoclonus is a sequence of repeated, often nonrhythmic, brief shock-like jerks due to sudden involuntary contraction or relaxation of one or more muscles. Tremor is a rhythmic back-and-forth or oscillating involuntary movement about a joint axis. Tics are repeated, individually recognizable, intermittent movements or movement fragments that are almost always briefly suppressible and are usually associated with awareness of an urge to perform the movement. Stereotypies are repetitive, simple movements that can be voluntarily suppressed. We provide recommended techniques for clinical examination and suggestions for differentiating between the different types of hyperkinetic movements, noting that there may be overlap between conditions. These definitions and the diagnostic recommendations are intended to be reliable and useful for clinical practice, communication between clinicians and researchers, and for the design of quantitative tests that will guide and assess the outcome of future clinical trials.