We present the case of a 36-year-old patient with a rapidly progressing SOD1-ALS, who was initially diagnosed as inflammatory acute motor axonal neuropathy due to contrast-enhancement of the lumbar spinal cord and a pure secondary motor neuron phenotype. Since the initiation of tofersen, disease progression and neurofilament levels impressively declined.
Keywords: ALS; Amyotrophic lateral sclerosis; MRI; SOD1 mutation; contrast enhancement.