The phenotypic spectrum of STXBP1-related encephalopathy ranges from infantile epileptic encephalopathy to intellectual disability with nonsyndromic or absent epilepsy. Although being frequently reported, the tremor associated with STXBP1 has not been fully characterized to date. The aim of our study was to describe it. We recruited patients with intellectual disability due to STXBP1 variants, regardless of their epileptic phenotype, who had tremor at examination and who underwent neurophysiological testing including polymyographic registration of upper limbs muscles activity at rest, during posture maintenance and action. Six patients met the inclusion criteria over four years. Clinically, all had a postural and action distal tremor increased by emotions. Neurophysiological recordings showed a specific myoclonus pattern and were highly suggestive of a subcortical generator. The tremor-like observed in STXBP1 encephalopathy is due to a subcortical pseudo-rhythmic myoclonus.

STXBP1相关脑病的表型范围从婴儿癫痫性脑病到非综合征性或无癫痫的智力障碍。尽管经常被报道，但迄今为止，与STXBP1相关的震颤尚未得到充分表征。我们研究的目的是描述它。我们招募了STXBP1导致的智力障碍患者变体，无论其癫痫表型如何，在检查时有震颤并接受神经生理学测试，包括在休息时、姿势维持和动作期间上肢肌肉活动的多肌图记录。6 名患者在四年内符合纳入标准。临床上，所有患者都有因情绪而加重的姿势性和动作性远端震颤。神经生理学记录显示特定的肌阵挛模式，高度提示皮层下发生器。在STXBP1脑病中观察到的震颤样是由于皮层下假性节律性肌阵挛。