Clinical and Radiological Heterogeneity in Anti-Neurofascin-155 Autoimmune Nodopathy: A Case Series Analysis

Area of Science:

• Neurology
• Immunology
• Neuroscience

Background:

• Autoimmune nodopathy with anti-neurofascin-155 (NF155) antibodies is an emerging neurological disorder.
• Previous studies have described these patients, but a comprehensive understanding of their clinical characteristics, biomarkers, and treatment responses is lacking.

Purpose of the Study:

• To investigate the clinical phenotypes, biomarker profiles, and treatment outcomes in patients with anti-NF155 antibody-positive autoimmune nodopathy.
• To elucidate the disease characteristics and identify optimal treatment strategies for this condition.

Main Methods:

• Retrospective analysis of seven Japanese patients (aged 13-27 years) with anti-NF155 antibody-positive autoimmune nodopathy.
• Evaluation of clinical, electrophysiological, radiological, and biomarker data, including serum neurofilament light chain (sNfL) and anti-NF155 antibody levels in serum and cerebrospinal fluid (CSF).
• Longitudinal follow-up of one refractory case for over 80 months.

Main Results:

• All patients presented with severe sensory ataxia and motor dysfunction.
• Five patients had trigeminal nerve hypertrophy, and one had pes cavus. A pronounced demyelinating neuropathy phenotype was observed in all.
• Corticosteroids showed good to partial responses in all patients, while rituximab markedly improved a refractory case. IVIg had minimal efficacy. Anti-NF155 antibody and sNfL levels correlated with clinical status. Persistent nerve root hypertrophy was noted on MRI despite functional improvement.

Conclusions:

• Anti-NF155 nodopathy is a distinct, biomarker-trackable neurological entity.
• Corticosteroids and rituximab are more effective than IVIg, challenging current treatment paradigms.
• Antibody testing for anti-NF155 is essential for diagnosing and managing young patients with severe demyelinating neuropathy.