GAD2 and viral encephalitis: Among the included PWAE, anti-NMDAR encephalitis accounted for the highest proportion at 38.10% (32/84), followed by anti-LGI1 encephalitis at 30.95% (26/84), AE with co-existence of multiple anti-neuronal antibodies at 9.52% (8/84), anti-CASPR2 encephalitis at 8.33% (7/84), anti-GABABR encephalitis at 7.14% (6/84), and anti-GAD65 encephalitis at 5.95% (5/84).