(038) Muddy Waters— Depression, ECT, and Autoimmune Encephalitis Post COVID-19

Abstract:

Background: SARS-CoV-2 infection has been reported to trigger autoimmunity, including various encephalitides (Payus, 2021). We describe an unusual case of altered mental status in an elderly patient who recently recovered from SARS-CoV-2 and underwent inpatient ECT for treatment-refractory depression. Her presentation, initially considered delirium secondary to ECT, resulted in a diagnosis of autoimmune encephalitis (AE) after extensive neurological workup.

Case: The patient is a 79-year-old female with a history of recent SARS-CoV-2 infection and treatment-resistant major depressive disorder with prior response to ECT. The patient experienced depressed mood, anxiety, anhedonia, amotivation, and poor appetite for months prior to admission. After days of low PO intake at home, she presented to the ED with failure to thrive and was admitted to the psychiatric unit for ECT.

After the third treatment, she developed prolonged confusion, waxing and waning mental status, and generalized tremors. Neurology was consulted and additional tests including CBC, BMP, LFTs, and ammonia level were within normal limits. EEG, MRI, and lumbar puncture for viral CSF, Creutzfeldt Jakob Disease, and paraneoplastic panel testing (including neuronal receptor antibodies) were all negative with the exception of positive neuronal AChR ganglionic (alpha-3) antibodies, suggesting AE. A five-day course of IVIG improved her confusion, tremors, and mood.

Discussion: Our patient’s depressed mood, neurovegetative symptoms, and mental status changes seemed consistent with a combined presentation of major depressive disorder and delirium secondary ECT. Therefore, AE was initially considered unlikely. AE secondary to alpha-3 ganglionic acetylcholine receptor antibodies is associated with dysautonomia, seizures, and malignancy (Bansal, 2016). Our patient had no history of malignancy and experienced predominantly neuropsychiatric symptoms, which are less common in this AE subtype (McKeon, 2009). However, she contracted SARS-CoV-2 approximately two months prior to her admission. Current literature includes case reports of AE in SARS-CoV-2 patients (Payus, 2021). Thus, prior SARS-CoV-2 infection may have played a role in her development of AE. As AE can be a confounding diagnosis for delirium and depression, this case highlights the importance of maintaining a broad differential, even in cases where psychiatric symptoms are predominant.

References:
1. Payus AO, Jeffree MS, Ohn MH, et al. Immune-mediated neurological syndrome in SARS-COV-2 infection: A review of literature on autoimmune encephalitis in COVID-19. Neurological Sciences. 2021;43(3):1533-1547. doi:10.1007/s10072-021-05785-z.

2. Bansal P, Zutshi D, Suchdev K, Azher I, Mohamed W. Alpha 3 ganglionic acetylcholine receptor antibody associated refractory status epilepticus. Seizure. 2016;35:1-3. doi:10.1016/j.seizure.2015.12.008.

3. McKeon A, Lennon VA, Lachance DH, Fealey RD, Pittock SJ. Ganglionic acetylcholine receptor autoantibody. Archives of Neurology. 2009;66(6). doi:10.1001/archneurol.2009.78.