EEG is sensitive in early diagnosis of anti NMDAR encephalitis and useful in monitoring disease progress
- Author:
Suhailah Abdullah
;
Kheng Seang Lim
;
Won Fen Wong
;
Hui Jan Tan
;
Chong Tin Tan
- Publication Type:Journal Article
- MeSH:
Electroencephalography
- From:Neurology Asia
2015;20(2):167-175
- CountryMalaysia
- Language:English
-
Abstract:
Background& Objective: Investigation modalities, such as MRI and CSF examination, are neither
sensitive nor specific in the early phase of anti-NMDAR encephalitis. Nuclear imaging may be
useful to monitor the response to treatment but limited by the availability.We aimed to determine
the role of EEG as a tool for early diagnosis as well as a tool to assess disease progression and
response to treatment. Methods: A total of 99 EEGsdone in 16 patients diagnosed with anti-NMDAR
encephalitis throughout the course of illness, were reviewed retrospectively. The EEG changes were
correlated with the clinical presentations and response to treatment. Sixteen EEGs of patients with
schizophrenia and mood disorder, and 10 EEGs of patients with infective encephalitis were included
as control. Results: EEGs performed during the psychiatric and cognitive dysfunctionphase in patient
with anti-NMDAR encephalitis, showed diffuse background slowing in the delta-theta range in all the
patients. Serial EEGs showed that the dominant background frequency improved with improvement in
cognitive status. Nine patients had complete recovery with normalisation of the EEG abnormalities.
Eight patients had their typical clinical seizure recorded during EEG monitoring, but only 2 (25.0%)
with EEG correlation. Ten patients had status epilepticus (62.5%), 5 had EEG recorded during their
status epilepticus, of which only one with EEG correlation (20.0%). Eleven patients had asymmetric
background (68.8%), but only 1 has correlation with focal changes in the MRI brain (9.1%). Even
though the EEGs of patients with infective encephalitis also showed background slowing, their CSF
analysis was supportive of an infective cause. EEGs of patients with established psychiatric disorder
were within normal limits.
Conclusion: EEG abnormality has a good correlation with the degree of psychiatric and cognitive
dysfunction in patient with anti-NMDAR encephalitis, and is useful in early diagnosis, monitoring the
progress and the response to treatment. However, it has poor correlation with clinical seizures.
- Full text:P020150707357194541657.pdf
