Key features of syndromes associated with neuronal surface antibodies
| Antibody | Demographics | Key distinguishing features | Tumour associations | |
|---|---|---|---|---|
| Age predominance | F:M ratio | |||
| NMDAR | Children and adults <40 years | 4:1 | Psychiatric features followed by movement disorder (classically orofacial dyskinesia), seizures, encephalopathy and autonomic dysfunction | About 50% of female patients have ovarian teratoma; other tumour associations have been described |
| LGI1 | Older adults | 1:2 | Faciobrachial dystonic seizures, amnesia, hyponatraemia | <10%: breast, lymphoma, thymoma, thyroid |
| CASPR2 | Older adults | 1:9 | Sleep disorders (insomnia, sleep-wake cycle disturbance), peripheral nerve hyperexcitability, ataxia | <5%: various tumours |
| GABAAR | Children or adults | 1:1 | Seizures | 30%: thymoma |
| GABABR | Older adults | 1:1.5 | Seizures, amnesia | 50%: SCLC |
| AMPAR | Older adults | 2:1 | Amnesia | 65%: breast, SCLC, thymoma |
| DPPX | Adults | 1:2 | Severe diarrhoea and weight loss, myoclonus, hyperekplexia | <10%: lymphoma |
AMPAR = α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor; CASPR2 = contactin-associated protein-like 2; DPPX = dipeptidyl-peptidase-like protein 6; GABAAR = γ-aminobutyric acid type A receptor; GABABR = γ-aminobutyric acid type B receptor; LGI1 = leucine-rich glioma-inactived 1; NMDAR = N-methyl-D-aspartate receptor; SCLC = small cell lung cancer.