Glial Fibrillary Acidic Protein Autoimmunity After Aseptic Meningitis: A Report of 2 Cases

OBJECTIVES: We describe 2 patients with glial fibrillary acidic protein (GFAP) autoimmunity secondary to aseptic viral meningitis or meningoencephalomyelitis. METHODS: This study involved a retrospective chart review. RESULTS: Two female patients, 45 and 55 years of age, developed aseptic meningoencephalomyelitis or meningitis; in one patient, it was likely caused by herpes simplex virus 2. The patients were recovering from the infectious condition when they, 51 and 5 days after onset, had new symptoms with detection of GFAP antibodies in the CSF; CSF and serum samples from the initial lumbar punctures had been negative for GFAP antibodies. Both patients recovered with steroid treatment (in one case, plus rituximab; in the other, plus azathioprine) including resolution of MRI and CSF abnormalities. DISCUSSION: These 2 patients had GFAP autoimmunity secondary to viral meningoencephalomyelitis or meningitis. This suggests that GFAP astrocytopathy might not always be a primary disease entity; it may follow another brain injury that triggers this autoimmune response.