D'hoore Pauline, Terryn Joke
Department of Neurology, University Hospitals Leuven, Leuven, Belgium.
Clin Neurophysiol Pract. 2025 Jun 17;10:218-221. doi: 10.1016/j.cnp.2025.06.004. eCollection 2025.
Methotrexate (MTX) is widely used in the treatment of acute lymphocytic leukemia (ALL) and other onco-hematological conditions. Although subacute MTX-related neurotoxicity is relatively rare, it can present with dramatic, fluctuating neurological deficits that mimic other serious conditions. Diagnosis may be complicated by the frequent presence of asymptomatic white matter abnormalities on MRI, commonly attributed to chronic MTX toxicity. We report an 18-year-old ALL patient who developed severe, fluctuating neurological symptoms 11 days after the third intrathecal administration of MTX. MRI showed bilateral, symmetric diffusion-restrictive white matter lesions. Absent cortical motor evoked potentials (MEPs) with preserved responses to spinal stimulation indicated corticospinal tract involvement localized to the brain, supporting a diagnosis of MTX-induced neurotoxicity. Treatment with high-dose dextromethorphan led to rapid and complete recovery. This case underscores the value of early neurophysiological testing - particularly MEPs - in identifying corticospinal tract involvement and differentiating symptomatic neurotoxicity from chronic, asymptomatic MRI findings. Prompt recognition can accelerate diagnosis, guide treatment, and prevent unnecessary interventions.
甲氨蝶呤（MTX）广泛应用于急性淋巴细胞白血病（ALL）及其他血液肿瘤疾病的治疗。虽然亚急性MTX相关神经毒性相对少见，但可表现出显著且波动的神经功能缺损，类似其他严重疾病。由于MRI上经常出现无症状性白质异常，通常归因于慢性MTX毒性，这可能使诊断变得复杂。我们报告一名18岁的ALL患者，在第三次鞘内注射MTX后11天出现严重且波动的神经症状。MRI显示双侧对称的扩散受限白质病变。皮质运动诱发电位（MEP）缺失但对脊髓刺激反应保留，提示皮质脊髓束受累局限于脑部，支持MTX诱导的神经毒性诊断。高剂量右美沙芬治疗导致快速且完全恢复。该病例强调了早期神经生理学检测（尤其是MEP）在识别皮质脊髓束受累以及区分症状性神经毒性与慢性无症状MRI表现方面的价值。及时识别可加速诊断、指导治疗并避免不必要的干预。
