Table 1.

Clinical and laboratory features of patients with epilepsy and positive neuronal surface autoantibodies

Age	Sex	Autoantibody	Live hippocampal neuron binding	APE2 score	Criteria AE	Clinical AE	Pilo	Epil RF	Lowered Mood	ACE Att	MRI Δlimbic	Number of ASMs	mRS 1 year	mRS 3 years	Immunotherapy
79	M	CASPR2	+	3	Definite	Yes	No	None	No	14	Yes	2	3	2	IVMP, Pred, IVIg, PLEX
55	F	CASPR2		6	Definite	Yes	No	None	Yes	18	Yes	3	2	2	IVMP, Pred, IVIg, PLEX
55	F	GABABR	+	9	Definite	Yes	No	None	No	NA	Yes	6	6	NA	IVMP, Pred, PLEX
18	F	NMDAR	+	8	Definite	Yes	No	None	Yes	15	Yes	3	2	2	IVMP, Pred, PLEX, Aza, MMF
60	F	NMDAR		4	Definite	Yes	No	None	Yes	13	No	3	0	0	Pred
77	F	GABAAR, GABABR	+	8	Possible	Yes	No	None	Yes	18	Yes	4	1	0	Pred
54	M	LGI1	+	6	Possible	Yes	Yes	None	Yes	18	Yes	2	0	0	None
59	F	LGI1	+	4	No	Yes	No	None	Yes	18	No	1	1	0	None
69	M	Unknown	+	4	No	Yes	No	None	No	13	No	1	1	2	Pred, Aza
63	M	AMPAR	+	2	No	No	No	None	No	NA	No	1	0	0	None
28	M	CASPR2		2	No	No	No	FHx	Yes	17	No	1	0	0	None
41	F	CASPR2		2	No	No	No	None	Yes	18	No	0	0	0	None
75	F	Contactin-2		1	No	No	No	None	No	NA	No	1	0	0	None
37	F	GABAAR		2	No	No	No	None	Yes	18	No	2	0	0	None
36	F	GABABR		2	No	No	No	None	No	18	No	1	1	0	None
69	F	GlyR		4	No	No	No	None	Yes	15	No	4	1	1	None
61	M	LGI1	+	2	No	No	Yes	None	Yes	18	No	1	0	0	None
36	F	NMDAR		2	No	No	No	None	Yes	18	No	1	2	2	None
68	F	NMDAR, GABAAR		1	No	No	No	None	No	18	No	1	0	0	None
77	F	Unknown	+	2	No	No	No	None	Yes	NA	No	0	0	NA	None
55	F	Unknown	+	4	No	No	No	None	Yes	18	No	5	2	2	None
91	M	Unknown	+	1	No	No	No	None	No	9	No	1	6	NA	None
37	M	Unknown	+	2	No	No	No	None	Yes	18	No	2	0	0	None

APE2 score of 4 or more is considered positive. Diagnosis of encephalitis based on clinical impression (‘Clinical AE’; corresponding rows shaded in grey) or published criteria (‘Criteria AE’), as per Graus et al.¹¹

‘Unknown’ autoantibody specificities reflect IgG binding to the surface of live hippocampal neurons, without a known antigenic target.

ACE Att, Addenbrooke’s Cognitive Examination attention domain score; AE, autoimmune encephalitis; APE2, Antibody Prevalence in Epilepsy and Encephalopathy Score; ASM, anti-seizure medication; Aza, azathioprine; Epil RF, epilepsy risk factors (neonatal, perinatal, focal neurological insults, family history of epilepsy or Alzheimer’s disease); FHx, family history; IVIg, intravenous immunoglobulin; IVMP, intravenous methylprednisolone; mRS, modified Rankin Score; Myco, mycophenolate; NA, not available; PLEX, plasma exchange; Pred, prednisolone.