N-Methyl-D-Aspartate Encephalitis our Experience with Diagnostic Dilemmas, Clinical Features, and Outcome.

INTRODUCTION: A neuropsychiatric syndrome characterized by a wide spectrum of clinical manifestations. It is seen in patients with antibodies against NR1-NR2 heteromers of the NMDA receptor. As the spectrum is mainly psychiatric most patients are treated as psychiatric disease resulting in huge diagnostic delay. PATIENT AND METHODS: Here we describe 29 patients with NMDA encephalitis seen by the authors in the last five years. Percentage of Transfected cells showing granular cytoplasmic florescence was considered for positivity and severity both in CSF and serum. Their presenting diagnosis, clinical features and the dilemmas, alarming gaps, laboratory data, response to treatment and relapses are discussed. OBSERVATIONS: All patients presented with a spectrum of psychiatric symptoms varying from panic to severe aggression, seizures, chorea, hemiplegia, catatonia, mitgehen, mutism, delirium, mania and memory problems. EEG is invariably abnormal as against imaging. CONCLUSION: NMDA receptor mediated encephalitis should be suspected in all children and females of adolescent age with refractory neuropsychiatric syndrome. Both CSF and serum should be tested and regular follow up for relapses and neoplasms is mandatory.