Autoimmune Glial Fibrillary Acidic Protein Astrocytopathy Presenting with Slowly Progressive Myelitis and Longitudinally Extensive Spinal Cord Lesions.

We report a 65-year-old man with autoimmune glial fibrillary acidic protein astrocytopathy (GFAP-A) who presented with gait disturbance that he had experienced for approximately half a year. On neurological examination, he displayed spastic paraplegia and autonomic dysfunctions including dysuria and constipation. Spinal cord magnetic resonance imaging showed longitudinally extensive spinal cord lesions (LESCLs) extending from the cervical to the thoracic cords. The patient was negative for anti-myelin oligodendrocyte glycoprotein and anti-aquaporin 4 antibodies. Treatment with corticosteroids and intravenous immunoglobulin resulted in a clinical improvement. It is important to distinguish GFAP-A from slowly progressive myelitis with LESCLs.