Introduction Nivolumab is a programmed death 1 (PD-1) inhibitor approved by the Food and Drug Administration (FDA) for the treatment of eight different cancers including metastatic melanoma. Immune checkpoint blockade may lead to a range of neurologic immune-related adverse events (irAEs) with severity varying from mild to life-threatening, including encephalitis. Case report We describe a case of a 68-year-old man who developed alteration in mental status, physical weakness and fatigue after nine cycles of nivolumab 3 mg/kg every two weeks. These symptoms were compatible with a clinical diagnosis of autoimmune limbic encephalitis, although no specific antibodies were detected and the initial MRI was normal. Management and outcome The patient received intravenous methylprednisolone 1 g daily for 5 days, which was then converted to a maintenance dose of oral prednisone. The patient made a full clinical recovery but relapsed clinically upon steroid tapering, while hypersignal in the left mesial temporal suggestive of limbic encephalitis was observed on repeated MRI. Discussion Because of the prevailing usage of nivolumab in many cancer protocols, this case highlights the importance of rapidly recognising neurological impairment in patients treated with nivolumab and of initiating very high doses of corticosteroids.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.