Clinical characteristics of anti‐neurofascin 155 antibody‐positive autoimmune nodopathy in children

ABSTRACT Importance Anti‐neurofascin (anti‐NF) 155 antibody‐positive autoimmune nodopathy is a distinct subset of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). Given the increase in pediatric cases, understanding this condition is crucial. Objective This study aimed to delineate the clinical features of children with anti‐NF155 antibody‐positive autoimmune nodopathy to enhance disease management strategies. Methods We conducted a retrospective cohort study of 34 CIDP patients admitted to Beijing Children's Hospital from January 2015 to December 2024, including six with confirmed anti‐NF155‐antibody positivity. Their clinical symptoms, laboratory results, neuroimaging findings, and therapeutic responses were retrospectively analyzed. Results Of the 34 patients, six (17.6%) were tested positive for anti‐NF155 antibodies. The cohort was male‐dominated (male‐to‐female ratio of 4:2) with symptoms starting primarily in school‐aged children. The symptoms included progressive limb weakness, sensory ataxia, and tremors. Notably, cerebrospinal fluid (CSF) protein levels were significantly elevated in seropositive patients. Electrophysiological studies indicated sensorimotor polyneuropathy, and neuroimaging revealed nerve root thickening. While intravenous immunoglobulin (IVIG) therapy was not effective, a combination of glucocorticoids, rituximab, and plasma exchange showed promise. At the final follow‐up, all patients experienced symptom relief and could perform daily activities without relapse. Interpretation Pediatric anti‐NF155 antibody autoimmune nodopathy was uncommon, featuring male dominance, and distal weakness with sensory symptoms. Additionally, the CSF protein levels were significantly elevated in seropositive patients. As IVIG treatment was ineffective, early immunosuppressive therapy was recommended. Early diagnosis and treatment are critical in reducing myelin and axonal damage.