Table 2. Disease severity and treatment strategies according to serological status.

	Seronegative AIE (n=37)	Seropositive AIE (n=9)	p
Initial mRS score	4 [2]	5 [0]	0.086
mRS score after first-line treatment	1 [2]	4 [2]	0.003*
Final mRS score	1 [2]	1 [2]	0.703
First-line treatment	37 (100.0)	9 (100.0)	-
Second-line treatment	5 (13.5)	5 (55.6)	0.015*
Third-line treatment	0	1 (11.1)	0.196
Maintenance treatment	8 (21.6)	5 (55.6)	0.092
Relapse	13 (35.1)	2 (22.2)	0.696

Data are median [interquartile range] or n (%) values. First-line treatment: high-dose dexamethasone (0.6–0.8 mg/kg/day), pulsed intravenous methylprednisolone (20–30 mg/kg/day for 3–5 days), intravenous immunoglobulin (2 g/kg over 2–5 days), or therapeutic plasma exchange (5–10 exchanges every other day). Second-line treatment: rituximab (375 mg/m² weekly for 4 weeks) or cyclophosphamide (750 mg/m² monthly). Third-line treatment: tocilizumab (4–8 mg/kg monthly). Maintenance treatment: monthly administration of methylprednisolone or immunoglobulins, oral prednisone (1 mg/kg/day), mycophenolate mofetil, or azathioprine.

^*p<0.05.

AIE: autoimmune encephalitis, mRS: modified Rankin Scale.