Optic Neuritis With Glial Fibrillary Acid Protein Antibodies in the Setting of Nivolumab Use

Immune-checkpoint inhibitors(ICIs) have revolutionized cancer treatment by modulating/disinhibiting the immune system leading to infrequent immune-related adverse events (irAEs).1,2 Nivolumab is a PD-1 blocking-antibody immune-checkpoint inhibitor used to treat malignant melanoma, non-small cell lung cancer, and renal cell carcinoma. Glial fibrillary acidic protein(GFAP) is an astrocytic cytoplasmic intermediate-filament protein. GFAP-IgG meningoencephalomyelitis is a steroid-responsive autoimmune condition and sometimes paraneoplastic-related3,4 There have been rare reports of GFAP-IgG autoimmune meningoencephalitis after checkpointinhibitors, 5,6 but none with vision loss as the main finding.