Lesion-like effect of gliosis secondary to deep brain stimulation electrode infection: illustrative case.

backgroundDeep brain stimulation (DBS) is commonly used to treat Parkinson's disease (PD) and other movement disorders when other treatments fail. Although DBS can significantly improve motor symptoms, it carries risks such as infections, which can require multiple surgeries and prolonged antibiotic therapy. Research on the long-term neurological effects of DBS-related infections is limited. OBSERVATIONS: A 58-year-old man with a 13-year history of PD, refractory to optimized clinical management, underwent subthalamic nucleus (STN) DBS after previous contralateral lesioning of the posterior subthalamic area. Postoperatively, the DBS lead migrated upward and was repositioned, but he developed perielectrode cerebritis 5 days later. The DBS system was completely removed, and he underwent a 28-day course of intravenous antibiotics. Initially, his motor symptoms remained unchanged, but 4 months later, he experienced a significant and sustained motor symptom improvement that continued until the last follow-up assessment (40 months). Magnetic resonance imaging performed 2 years after the explantation showed gliosis and hemosiderin deposition in the STN, suggesting that the infection-induced gliosis had a lesion-like effect, leading to the observed clinical improvement. LESSONS: This case suggests that infection-induced gliosis from DBS complications can unexpectedly result in long-term motor symptom improvements, potentially influencing future management strategies for similar cases. https://thejns.org/doi/10.3171/CASE24502.