Autoimmune encephalitis

Question 1

Antibodies against neuronal cell surface or synaptic receptors

Answer 1

NMDAR
AMPAR
GABAR
LGI1

GABA-A = more serious seizures
GABA-B = more limbic involvement, with more mood and memory symptoms

Question 2

Antibodies against intracellular antigens

Answer 2

Less responsive to treatment, more often associated with tumours

anti-Hu
anti-Ma
anti-GAD

Question 3

NMDAR

Answer 3

Hippocampal neurons

Psychosis, involuntary movements (e.g. orofacial dyskinesias), catatonia, mutism, seizures, reduced consciousness

Ovarian teratomas, sometimes other tumours in patients >45

Often follows a viral like illness

Question 4

LGI1 (VGKC complex)

Answer 4

Hippocampal neurons

Amnesia, seizures (faciobrachial), encephalopathy, hyponatraemia

Rare tumour association

Usually monophasic

Question 5

CASPR2 (VGKC complex)

Answer 5

Hippocampal neurons

Encephalopathy, autonomic disturbance, insomnia, pain, amnesia (Morvan’s)

Thymoma, small cell lung ca

Question 6

AMPAR

Answer 6

Widespread in CNS

Amnesia, psychosis, seizures

Thymoma, breast or lung ca (50%)

Question 7

GABA-BR

Answer 7

Widespread in CNS

Mainly seizures with other limbic encephalitis features

Thymoma and lung (80%)

Question 8

GAD

Answer 8

Inhibitory interneurones

Complex partial seizures, cognitive impairment

Rare tumour association

Question 9

GlyR

Answer 9

Inhibitory interneurones (mainly in brainstem and spinal cord)

Stiffness, exaggerated startle reflexes, rigidity, rarely cognitive impairment

Rare tumour association