Anti-GLDN antibody-associated CIDP (nodopathy): transient IVIg response and B-cell depletion remission.

BACKGROUND

The classification of chronic inflammatory demyelinating polyneuropathy (CIDP) is evolving with the discovery of autoantibodies against nodal and paranodal proteins, leading to the recognition of "autoimmune nodopathies." While anti-neurofascin-155 (NF155) and anti-contactin-1 (CNTN1) antibodies are well-characterized, the phenotype of anti-gliomedin (GLDN) antibodies remains poorly defined. We present a comprehensive case to delineate its clinical and serological profile.

CASE PRESENTATION: We report a detailed longitudinal case of a patient with anti-GLDN antibody-positive CIDP, including clinical presentation, electrophysiological and imaging studies, serological testing, treatment response, and follow-up.

RESULTS

A 48-year-old woman presented with an 11-month history of relapsing-remitting, symmetric sensorimotor polyneuropathy, triggered by immune-activating events. Electrodiagnostic studies confirmed a demyelinating polyneuropathy meeting definitive European Academy of Neurology/Peripheral Nerve Society (EAN/PNS) criteria. Cerebrospinal fluid (CSF) analysis showed marked albuminocytological dissociation (protein 1631 mg/L). Serology was positive for anti-GLDN IgG (cell-based assay titer 1:32). The patient exhibited an excellent but transient response to intravenous immunoglobulin (IVIg), leading to multiple relapses. Subsequent B-cell targeted therapy with rituximab resulted in sustained clinical stabilization, effective B-cell depletion, and negative conversion of anti-GLDN IgG antibody.

CONCLUSIONS

This case suggests that anti-GLDN antibody-associated CIDP may be associated with a recognizable phenotype within the autoimmune nodopathy spectrum. Potential key features include a relapsing course following immune stimulation, markedly elevated cerebrospinal fluid protein, a unique pattern of robust but unsustained response to intravenous immunoglobulin (IVIg), and a favorable response to B-cell depletion therapy as evidenced by clinical remission and seroconversion.