METHODS: Patient 1: A 2.5-year-old girl was diagnosed with SMA type I at 1 month of age. She received nusinersen four times and onasemnogene abeparvovec (OA) was administered at 6 months of age. The compound muscle action potential (CMAP) amplitudes of the median and tibial nerves increased over time. The needle EMG after the treatment showed high-amplitude motor unit potentials (MUPs) suggestive of reinnervation during voluntary contraction, which were not seen before the treatment. However, fibrillation potentials at rest were still seen after the treatment. Patient 2: A 2-year-old girl was diagnosed with SMA type I at 6 months of age. She had received nusinersen two times and OA was administered at 7 months of age. The CMAP amplitudes and the MUPs presented similar changes as presented in Case 1.
CONCLUSIONS: This is the first report on the changes in needle EMG findings after treatment in patients with SMA type I. These findings suggested that peripheral nerve reinnervation occurred after the treatment, although active denervation was still present. The accumulation of these findings will be important for evaluating the effectiveness of treatment for SMA in the future.
方法:患者1:1名2.5岁女孩在1月龄时被诊断为SMAI型.她接受了nusinersen四次,并在6个月大时服用了asemnogeneabeparvovec(OA)。正中和胫神经的复合肌肉动作电位(CMAP)振幅随时间增加。治疗后的针头肌电图显示高振幅运动单位电位(MUP),提示在自愿收缩期间神经支配,这是在治疗前没有见过的。然而,治疗后仍可见休息时的纤颤电位。患者2:2岁女孩在6月龄时被诊断患有I型SMA。她曾两次接受nusinersen,并在7个月大时给予OA。CMAP振幅和MUP呈现与情况1中呈现的相似的变化。
结论:这是有关I型SMA患者治疗后针状肌电图变化的首次报道,这些发现表明治疗后发生了周围神经神经支配,尽管仍存在主动去神经支配。这些发现的积累对于评估未来SMA治疗的有效性将是重要的。