Immune checkpoint inhibitor-associated autoimmune encephalitis-an emerging cause for encephalitis

• Published in: BMJ case reports Vol. 17; no. 6; p. e259018
• Main Authors: Herath, Tharuka Milinda, Mbydeen, Tsneem H S, Saleh, May, Sunil Wimalaratna, Sunil Wimalaratne
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group LTD 05.06.2024
• Subjects: Antibodies; Autoimmune diseases; Blood; Case reports; Cerebrospinal fluid; Encephalitis; Encephalitis - diagnosis; Encephalitis - immunology; Female; Hashimoto Disease - complications; Hashimoto Disease - diagnosis; Hashimoto Disease - drug therapy; Humans; Immune Checkpoint Inhibitors - adverse effects; Immunosuppressive agents; Male; Pathogens; Proteins; Steroids; Neuroimaging; Immunology
• ISSN: 1757-790X; 1757-790X
• DOI: 10.1136/bcr-2023-259018

CSF cultures and PCR tests for bacterial, viral, mycobacterial and fungal pathogens, including Cryptococcus, were negative. Infective pathology was another possibility; however, CSF cultures and PCR tests for various pathogens, including bacteria, viruses, mycobacteria and fungi (including Cryptococcus), returned negative results. ICI is known to cause autoimmune side effects, including encephalitis and is an increasingly recognised adverse event with ICI treatment.1 The clinical presentation of ICI-AIE is variable, ranging from mild cognitive impairment to coma, seizures or focal neurological deficits. Additional immunosuppressive agents, such as intravenous immunoglobulin, plasmapheresis or rituximab, are also proposed, depending on the severity of the presentation.2 Here, we want to highlight that clinicians are likely to encounter ICI-AIE more often in the future and the diagnosis is based on the clinical history, the exclusion of other causes of encephalopathy and the supportive evidence from MRI and CSF analysis.