Biological signaling
Results showed that 15 patients presented with suicidal thoughts and/or behaviors. Of this subgroup, the median age was 32 years (range, 19-48 years) and 53.3% were women.
All members of this subgroup had psychotic features, including persecutory, grandiose, nihilistic, or jealousy delusion (n = 14), delirium (n = 13), visual or auditory hallucinations (n = 11), psychotic depression (n = 10), and/or catatonia (n = 8).
Most (n = 12) had suicidal ideation with intent, three had preparatory behaviors, and seven actually engaged in suicidal self-directed violence.
Of these 15 patients, 7 had abnormal CSF findings, 8 had MRI abnormalities involving the medial temporal lobe, and all had abnormal EEG involving generalized slowing.
Fourteen suicidal patients were treated with an antipsychotic, 4 with dexmedetomidine, and 12 with lorazepam. In addition, 10 received plasmapheresis and 7 received immunoglobulin.
Of note, at discharge, self-directed violent thoughts and behaviors completely remitted in 14 of the 15 patients. Long-term follow-up showed that they remained free of suicidality.
Dr. Ramirez-Bermúdez noted that in some patients with neuropsychiatric disturbances, “there are autoantibodies against the NR1 subunit of the NMDA glutamate receptor: the main excitatory neurotransmitter in the human brain.”
The NMDA receptor is “particularly important as part of the biological signaling that is required in several cognitive and affective processes leading to complex behaviors,” he said. NMDA receptor dysfunction “may lead to states in which these cognitive and affective processes are disturbed,” frequently resulting in psychosis.
Study coauthor Ava Easton, MD, chief executive of the Encephalitis Society, told this news organization that mental health issues, self-injurious thoughts, and suicidal behaviors after encephalitis “may occur for a number of reasons and stigma around talking about mental health can be a real barrier to speaking up about symptoms; but it is an important barrier to overcome.”
Dr. Easton, an honorary fellow in the department of clinical infection, microbiology, and immunology, University of Liverpool, England, added that their study “provides a platform on which to break taboo, show tangible links which are based on data between suicide and encephalitis, and call for more awareness of the risk of mental health issues during and after encephalitis.”
‘Neglected symptom’
Commenting on the study, Carsten Finke, MD, Heisenberg Professor for Cognitive Neurology and consultant neurologist, department of neurology at Charité, Berlin, and professor at Berlin School of Mind and Brain, said that the research was on “a very important topic on a so far rather neglected symptom of encephalitis.”
Dr. Finke, a founding member of the scientific council of the German Network for Research on Autoimmune Encephalitis, was not involved in the current study.
He noted that 77% of people don’t know what encephalitis is. “This lack of awareness leads to delays in diagnoses and treatment – and poorer outcomes for patients,” Dr. Finke said.
Dr. Michael E. Benros
Also commenting, Michael Eriksen Benros, MD, PhD, professor of immune-psychiatry, department of immunology and microbiology, Health and Medical Sciences, University of Copenhagen, said that the study “underlines the clinical importance of screening individuals with psychotic symptoms for suicidal ideations during acute phases,” as well as those with definite ANMDARE as a likely underlying cause of the psychotic symptoms.
This is important because patients with ANMDARE “might not necessarily be admitted at psychiatric departments where screenings for suicidal ideation are part of the clinical routine,” said Dr. Benros, who was not involved with the research.
Instead, “many patients with ANMDARE are at neurological departments during acute phases,” he added.
The study was supported by the National Council of Science and Technology of Mexico. Dr. Ramirez-Bermúdez, Dr. Easton, Dr. Benros, and Dr. Finke report no relevant financial relationships.
A version of this article first appeared on Medscape.com.