Case Report: Combined central and peripheral nerve demyelination with neurofilament heavy chain antibodies.

Combined central and peripheral demyelination (CCPD) is a rare chronic demyelinating disorder. Neurofilament (NF) proteins are structural components specific to neuronal intermediate filaments within axons. The presence of anti-neurofilament antibodies is typically associated with axonal pathology and is seldom observed in patients with CCPD. We present a case of CCPD in a patient who tested positive for immunoglobulin G (IgG) antibodies against the neurofilament heavy chain (NF-H-IgG) in both cerebrospinal fluid (CSF) and serum. Since 2019, the patient has exhibited a constellation of neurological symptoms, including severe neck and shoulder pain, left-sided limb weakness, distal extremity numbness, left-eye visual blurring, and impaired deep sensation. Electrophysiological and clinical evaluations indicated a primarily demyelinating peripheral neuropathy with secondary axonal involvement. Following treatment with low-dose corticosteroids in combination with cyclophosphamide (CTX), the patient demonstrated marked clinical improvement.