Autoimmune glial fibrillary acidic protein astrocytopathy manifesting as subacute meningoencephalitis with descending myelitis: a case report

BACKGROUND: Glial fibrillary acidic protein (GFAP) autoimmune astrocytopathy is characterized by GFAP autoantibody positive encephalitis, meningoencephalitis or meningoencephalomyelitis. The initial clinical presentation may be similar to central nervous system infections making early diagnosis challenging. CASE PRESENTATION: A Chinese female patient presented with subacute meningitis with symptoms of headache, vomiting, and fever. Cerebrospinal fluid (CSF) analysis showed monocytic pleocytosis, elevated protein level, low glucose level, and negative basic microbiological studies including Xpert MTB/RIF. Brain magnetic resonance imaging (MRI) showed bilateral cerebral cortical and white matter hyperintensities on FLAIR sequences. The patient was diagnosed with possible tuberculous meningitis and started on anti-tuberculosis therapy (ATT). Three months later, the patient developed cervical myelopathy and encephalopathy with persistent CSF pleocytosis. Five months later, tissue-based and cell-based assays demonstrated GFAP antibodies in blood and CSF. Her symptoms improved with repeated administration of intravenous immunoglobulin (IVIG) and corticosteroids. One-and-a-half -year follow-up showed neither clinical progression nor relapses. CONCLUSIONS: Anti-GFAP astrocytopathy should be included in the differential diagnosis of patients who present with subacute meningitis with negative microbiological studies and a progressive clinical course including encephalitis and/or myelitis.