Of these, 180 patients were excluded due to receiving immunotherapy before laboratory examination (n = 33), with other autoimmune diseases (n = 27), with respiratory tract infection, urinary system infection, or other infectious diseases at the time of admission (n = 6), with mRS ≥ 2 points before the onset of AE (n = 1), with infectious encephalitis, epidemic encephalitis, unexplained encephalitis, central nervous system tumors, demyelinating diseases, and other neurological diseases (n = 56), not detecting RDW (n = 46), not detecting albumin (n = 7), and lost to follow-up (n = 4). Here, ALB is linked to Respiratory tract infection.