Supplementary Material for: Childhood Stiff-Person Syndrome Improved with Rituximab

<b><i>Introduction:</i></b> Stiff-person syndrome (SPS) is manifested by fluctuating rigidity of axial musculature with painful episodic spasms due to simultaneous co-contraction of agonist and antagonist muscles. We present a case report and video illustrating response to treatment with rituximab. <b><i>Materials and Methods:</i></b> Case description and video are provided. A literature search for other reports of treatment with rituximab was performed. <b><i>Results:</i></b> Nine cases in addition to our case were described. Substantial clinical benefit was reported in 7/9 (78%) cases. Four out of 9 (44%) cases displayed persistent anti-glutamic acid decarboxylase (GAD) antibody positivity. <b><i>Conclusion:</i></b> Rituximab is an important treatment strategy in SPS. The persistence of anti-GAD antibody positivity even with clinical remission remains to be elucidated.

**引言：** 僵人综合征（Stiff-person syndrome, SPS）以轴性肌肉波动性僵硬为核心表现，因主动肌与拮抗肌同时协同收缩，引发疼痛性阵发性痉挛。本文报告1例病例并附视频，展示患者对利妥昔单抗治疗的应答情况。
**材料与方法：** 本研究包含病例描述与视频资料，并针对利妥昔单抗治疗僵人综合征的其他相关病例报告开展了文献检索。
**结果：** 除本病例外，另有9例僵人综合征病例被报道。其中7例（78%）患者获得了显著临床获益；9例病例中4例（44%）持续呈抗谷氨酸脱羧酶（anti-glutamic acid decarboxylase, GAD）抗体阳性。
**结论：** 利妥昔单抗是治疗僵人综合征的重要策略；即便患者达到临床缓解，抗GAD抗体仍持续阳性的机制尚待阐明。