18 F-FDG PET/CT Findings in an Atypical Case of Glial Fibrillary Acidic Protein Meningomyelitis.

Gilal fibrillary acidic protein (GFAP) meningomyelitis is a rare autoimmune inflammatory disorder of the central nervous system, typically presenting with subacute encephalopathy, ataxia, optic neuritis, and cerebrospinal fluid (CSF) pleocytosis. It is characterized by the presence of GFAP-specific autoantibodies, which target astrocytes and cause widespread neuroinflammation. 18 F-FDG PET/CT plays a critical role in the early diagnosis of autoimmune encephalitides, particularly in cases where conventional MRI findings may be subtle or nonspecific. Here, we present a case of 21-year-old woman who presented with early morning occipital headache with fever, followed by progressive drowsiness and acute urinary retention. On clinical examination, meningeal signs were positive. MRI brain was suggestive of leptomeningeal enhancement involving the brain and spinal cord, and 18 F-FDG PET/CT was done for further evaluation.