(095) Unraveling First Episode Mania After Colon Cancer Resection: A Case Report on Autoimmune Encephalitis

Trainee Involvement: Yes

Background: There have been case reports of first episode mania and psychosis in patients with colon cancer (Shu et.al., 2021; Park et.al., 2019). In these cases, autoimmune encephalitis was diagnosed. Autoimmune encephalitis is also associated with many other disorders, and has been detected in patients with Alzheimer’s disease, schizophrenia, bipolar disorder, and depression (Luo et.al., 2022), and thus should be ruled out while working up these first episodes.

Case: A 62-year-old male with a recent diagnosis of colon cancer resection presents to the Emergency Department with a 2-week onset of erratic behaviors, mood lability, grandiosity, impulsivity, paranoia, visual hallucinations and insomnia. The patient was managed by the Consultation Liaison Psychiatry Department. Magnetic resonance imaging (MRI) revealed multiple patchy confluent nonspecific abnormal white matter foci of T2/FLAIR prolongation. Electroencephalogram (EEG) showed multifocal cerebral dysfunction. Lumbar puncture (LP) was remarkable for elevated protein, with borderline elevated nucleated cells with lymphocyte predominance (81%), and elevated red blood cells. Infectious workup was unrevealing. There was a high clinical suspicion for Autoimmune Encephalitis. Empirical plasmapheresis (PLEX) was started. A trial of Olanzapine was also initiated to treat manic and psychotic symptoms. His symptoms improved and the patient was discharged with plans to follow up with outpatient psychiatry.

Discussion: Standard treatments such as PLEX can be considered a life-saving treatment, leads to symptom remission (Pandey et.al., 2018) and safe discharge back to the community. Psychiatric medications can be used to help target symptoms; however, PLEX is the standard treatment in cases of mania and psychosis caused by autoimmune encephalitis.

Conclusion: In older patients presenting with first episode mania or psychosis, autoimmune encephalitis should be ruled out as a potential cause.

References

Luo, Y., Li, J., Jiang, F., Tan, A., Qin, X., Xiao, X., Wang, Z., Wang, P., Yi, Y., Li, J., Yuan, S., Liu, L., & Xiao, J. (2022). Autoimmune Encephalitis With Psychotic Manifestations and Cognitive Impairment Presenting as Schizophrenia: Case Report and Literature Review. Frontiers in psychiatry, 13, 827138. https://doi.org/10.3389/fpsyt.2022.827138

Pandey PK, Agarwal N, Gupta M. Therapeutic plasma exchange as a life-saving therapy in a suspected case of autoimmune encephalitis: A case report from a tertiary health-care center. Asian J Transfus Sci. 2018 Jul-Dec;12(2):173-175. doi: 10.4103/ajts.AJTS_112_17. PMID: 30692806; PMCID: PMC6327764.

Park BS, Son GM, Kim HS, et al. Anti-N-methyl-d-aspartate receptor encephalitis in a patient with colon cancer. Clin Neurol Neurosurg. 2019; 177: 114– 116.

Shu Y, He D, Ma X, Li J, Wu H, Chen C, Lu Z, Petersen F, Qiu W, Yu X. Infiltration of plasma cells in colorectal adenocarcinoma associated with autoimmune encephalitis. Ann Clin Transl Neurol. 2021 Feb;8(2):498-503. doi: 10.1002/acn3.51283. Epub 2021 Jan 5. PMID: 33400852; PMCID: PMC7886041.