Autoimmune nodopathies, an emerging diagnostic category

Area of Science:

• Neuroimmunology
• Neuropathology
• Autoimmune Diseases

Background:

• Antibodies targeting cell adhesion molecules at the node of Ranvier are increasingly identified in autoimmune neuropathies.
• These nodal/paranodal antibodies define a distinct clinicopathological entity separate from classical chronic inflammatory demyelinating polyneuropathy (CIDP).

Purpose of the Study:

• To review recent findings that establish autoimmune nodopathies (AN) as a novel category of autoimmune neuropathies.
• To highlight the unique characteristics and diagnostic implications of AN.

Main Methods:

• Review of recent scientific literature on autoimmune nodopathies.
• Analysis of clinical, pathological, and immunological data from patients with AN.
• Summary of findings from ultrastructural studies and animal models.

Main Results:

• AN encompass neuropathies mediated by antibodies against contactin 1, contactin-associated protein 1, neurofascin 155, and pan-neurofascin.
• Clinical presentations mimic Guillain-Barré syndrome (GBS) and CIDP but show differential response to intravenous immunoglobulin (IVIG).
• Pathology is restricted to the node of Ranvier, with specific antibody subclasses (IgG4, IgG3) correlating with disease phase and severity.
• Association with nephrotic syndrome is noted for anti-contactin1 and anti-pan-neurofascin antibodies.

Conclusions:

• Autoimmune nodopathies represent a distinct diagnostic category, differing pathologically from acquired demyelinating neuropathies.
• While overlapping clinically with GBS and CIDP, AN possess unique features warranting clinical suspicion.
• Nodal/paranodal antibodies are crucial for diagnosis and monitoring of autoimmune nodopathies.