Our patient showed all typical features of contactin-1 and Caspr-1 seropositive AN, such as acute and severe onset of neurological symptoms mimicking GBS, a relapse of symptoms and insufficient response to standard therapy, severe sensory impairment with prominent sensory ataxia, tremor, and neuropathic pain in the course, concomitant MGN, and typical electrophysiological features (1, 12, 17, 18). This evidence concerns the gene CNTN1 and sensory ataxia.