A Case Report of Autoimmune Encephalitis after Anti-SARS-CoV-2 Vaccination: The Role of Cognitive Impairments in the Diagnostic Process

Objective: Autoimmune encephalitis includes a heterogeneous group of rare and complex diseases, usually presenting with severe and disabling symptoms, such as behavioral changes, cognitive deficits, and seizures. Method: This report presents the case of a 26-year-old man who was diagnosed with autoimmune encephalitis following SARS-CoV-2 vaccination (<40 days). Symptoms first appeared in February 2022 with a temporal seizure, associated with confusion and memory loss. Psychiatric manifestations such as disorientation and altered thought contents emerged soon after. Results: Neuroimaging testing showed signs of hypometabolism in occipital, prefrontal, and temporal regions, whereas an extensive neuropsychological assessment revealed the presence of multiple alterations in memory, executive, and visuoconstructive processes. Conclusions: In this case, a combination of neuroimaging testing, psychiatric evaluation, and neuropsychological assessment provided evidence for a diagnosis of autoimmune encephalitis post-vaccination. Early recognition is essential in order to prevent clinical progression; avoid intractable epilepsy, brain atrophy, and cognitive impairment; and improve prognosis.