Clinical and Genetic Characteristics of Paroxysmal Kinesigenic Dyskinesia: A Single-Center Study and Literature Review.

Paroxysmal kinesigenic dyskinesia (PKD) is a genetically heterogeneous movement disorder primarily associated with PRRT2 variants. Recently, TMEM151A and KCNJ10 have emerged as additional PKD-associated genes. However, genotype-phenotype correlations remain poorly defined. In this study, we retrospectively analyzed 41 PKD patients from a single center in Southeastern China. All patients underwent comprehensive clinical evaluation and whole-exome sequencing (WES), with variant classification based on ACMG guidelines. Additionally, we conducted a literature review of PKD cohorts published since 2021 to compare the clinical characteristics of patients carrying PRRT2, TMEM151A, KCNJ10 variants, and those without identified mutations. A genetic diagnosis was achieved in 19/41 patients (46.3%), with PRRT2 being the most frequent. We identified five novel variants, including two in KCNJ10, two in TMEM151A, and one in PNKD. Compared to other groups, PRRT2-positive patients had the earliest onset and highest treatment response. TMEM151A-positive patients tended to exhibit more frequent attacks and a lower response to carbamazepine. KCNJ10-positive patients presented with later onset and ultra-brief attacks. Genetically negative cases displayed distinct features, including fewer auras and more unilateral, ultra-brief episodes, yet responded well to carbamazepine. PKD exhibits significant genotype-dependent clinical heterogeneity. Novel variants in TMEM151A and KCNJ10 expand the mutational spectrum and suggest emerging genotype-specific phenotypic trends. Systematic genetic and phenotypic profiling may guide more precise diagnosis and management of PKD.