Pediatric Movement Disorders of Unknown Etiology in Vietnam (VPeMD)

This observational patient registry aims to describe the clinical phenotypes and genetic findings of Vietnamese children with movement disorders of unknown etiology. Eligible participants are children with clinically confirmed movement disorders after evaluation by pediatric neurology specialists and after exclusion of clear acquired causes. The study will collect clinical data, neurological examination findings, available laboratory and imaging results, and video recordings of abnormal movements when consent is provided. Blood samples will be collected for whole-exome sequencing and related genetic analysis. Genetic variants will be classified according to accepted clinical genetics standards and compared with the patients' clinical phenotypes. The study is expected to improve understanding of the phenotypic and genotypic spectrum of pediatric movement disorders in Vietnam, support genetic counseling, and evaluate how genetic results may influence diagnosis, follow-up, prognosis, and treatment planning.

Inclusion Criteria: * Children younger than 18 years old. * Patients with clinically confirmed movement disorders based on direct examination and/or video review by at least two pediatric neurology specialists. * Patients with movement disorders of unknown etiology after appropriate neurological evaluation and exclusion of clear acquired causes. * Patients evaluated or treated at University Medical Center Ho Chi Minh City or Children's Hospital 1 during the study period. * Patients and/or legal guardians who provide written informed consent for study participation and genetic testing. Exclusion Criteria: * Patients with isolated or transient primary tic disorders. * Patients with a confirmed acquired cause of movement disorder. * Patients or legal guardians who decline participation or withdraw from the study. * Patients with insufficient clinical information or unavailable biological samples for genetic analysis.