Early occurrence of brief potentially ictal rhythmic discharges [B(I)RDs], and subsequent emergence of asymmetric extreme delta brush (EDB) in Anti-NMDA receptors encephalitis.

A 12 years-old boy was admitted in coma without motor deficit, with normal CT scan, CSF with lymphocytosis, and EEG showing B(I)RDS (Figure A). Continuous EEG (24 hours) and subsequent serial intermittent EEGs were performed. Seizures were not documented. Patient developed orofacial diskynesia and coreoathetosis movements affecting superior limbs. Later, EEG showed asymmetric EDB pattern (Figure B). MRi was unremarkable. After immunotherapy, his level of consciousness improved. Anti-NMDAr antibodies were detected in serum and CSF. B(I)RDS were described in critically ill patients, often associated with brain injury and seizures, but no reported in Anti-NMDAr encephalitis1. EDB has been described in AntiNMDAr encephalitis; however, their clinical significance remains to be determined2.