Diagnostic Value of N-methyl-D-aspartate Receptor Antibodies in Women With New-Onset Epilepsy

Abstract

Background: In women younger than 45 years, a new form of encephalitis associated with ovarian teratoma and presenting with seizures and psychiatric symptoms has been described. Most patients have antibodies to NR1/ NR2 heteromers of the N-methyl-D-aspartate receptor (NMDAR). Objective: To assess the frequency and significance of antibodies to NMDAR in otherwise unexplained newonset epilepsies in young women.

GABA B receptor antibodies in limbic encephalitis and anti-GAD–associated neurologic disorders

“…Complete recovery in the absence of immunotherapy has been reported in patients with anti-NMDAR encephalitis and emphasizes the concept that autoimmune synaptic encephalitides are underdiagnosed. 23 In this study, all patients with concurrent GABA B R-ab and GAD-ab had a paraneoplastic neurologic disorder. In the initial series, 2 of the 8 patients with idiopathic LE encephalitis had additional GAD-ab.…”

Autoimmune encephalitis: An emerging entity

“…Varying rates of tumour presence at diagnosis of NMDAR encephalitis have been recorded. Dalmau et al reports this to be about 25% 9 while others report much lower rates 21,22 . Florence et al studying 81 patients found that 30% of women younger than 18 years, and less than 10% of girls younger than 14 years had tumours 12 .…”

“…There is some data to show that children may have better outcome than adults with full recovery seen in above 70% 10 . Early immunosuppressive therapy and prompt tumour removal appears to favourably affect the outcome 18,21,27 . Even when treated, deficits and even death may not be avoidable in some 6,18,27 .…”

Autoimmune Epilepsies

“…Another typical feature of the anti-NMDAR encephalitis, episodic memory impairment, can be modeled by suppressing long-term potentiation through antibodies [81]. However, the frequent occurrence of seizures [82], and even status epilepticus [83], is not easily explained by an NMDAR hypofunction, as NMDAR blockers exert an antiepileptic effect and have been considered as treatment option in status epilepticus [84].…”