Self-remitting Elevation of Adenosine Deaminase Levels in the Cerebrospinal Fluid with Autoimmune Glial Fibrillary Acidic Protein Astrocytopathy: A Case Report and Review of the Literature

A 29-year-old man presented with a high-grade fever, headache, and urinary retention, in addition to meningeal irritation and myoclonus in his upper extremities. A cerebrospinal fluid (CSF) examination showed pleocytosis and high adenosine deaminase (ADA) levels with no evidence of bacterial infection, including Mycobacterium tuberculosis. T2-weighted brain magnetic resonance imaging showed transient hyper-intensity lesions at the splenium of the corpus callosum (SCC), bilateral putamen, and pons during the course of the disease. The CSF was positive for anti-glial fibrillary acidic protein (GFAP) antibodies. He was diagnosed with autoimmune GFAP astrocytopathy. The present case shows that the combination of an elevated ADA level in the CSF and reversible T2-weighted hyper-intensity on the SCC supports the diagnosis of autoimmune GFAP encephalopathy.