Anti-N-Methyl-D-Aspartate Receptor Encephalitis with Favorable Outcome Despite Prolonged Status Epilepticus

To describe a case of auto-immune encephalitis in an adolescent with favorable outcome despite prolonged status epilepticus. A 17 year old Asian man without previous medical history developed alteration of consciousness and partial seizures. The diagnosis of anti-N-methyl-D-aspartate receptor encephalitis was confirmed by the detection of specific antibodies in both cerebrospinal fluid and serum. The clinical course was complicated by prolonged status epilepticus which was refractory to a large number of antiepileptic drugs, including barbiturate coma. Immunomodulatory therapy included steroids, plasma exchanges, and intravenous immunoglobulins. After 86 days of intensive therapy, the patient regained consciousness progressively. Brain magnetic resonance imaging never demonstrated any lesion. Extensive search for a tumor was negative. At 12 month follow-up, the patient had made an excellent recovery. Auto-immune encephalitis is likely underdiagnosed in adolescents. In their most severe presentation, seizures may be resistant to a large number of anti-epileptic drugs, and the clinical improvement seems to be mainly because of the immunomodulatory therapy. Relapse is possible, as well as the delayed development of a teratoma or other tumor.