BackgroundRare cases of COVID-19 infection- and vaccine-triggered autoimmune diseases have been separately reported in the literature. In this paper, we report the first and unique case of new onset acute psychosis as a manifestation of lupus cerebritis following concomitant COVID-19 infection and vaccination in a previously healthy 26-year-old Tunisian female.Case presentationA 26-years old female with a family history of a mother diagnosed with schizophrenia, and no personal medical or psychiatric history, was diagnosed with mild COVID-19 infection four days after receiving the second dose of Pfizer-BioNTech COVID-19 vaccine. One month after receiving the vaccine, she presented to the psychiatric emergency department with acute psychomotor agitation, incoherent speech and total insomnia evolving for five days. She was firstly diagnosed with a brief psychotic disorder according to the DSM-5, and was prescribed risperidone (2 mg/day). On the seventh day of admission, she reported the onset of severe asthenia with dysphagia. Physical examination found fever, tachycardia, and multiple mouth ulcers. Neurological evaluation revealed a dysarthria with left hemiparesis. On laboratory tests, she had severe acute kidney failure, proteinuria, high CRP values, and pancytopenia. Immune tests identified the presence of antinuclear antibodies. Brain magnetic resonance imaging (MRI) revealed hyperintense signals in the left fronto-parietal lobes and the cerebellum. The patient was diagnosed with systemic lupus erythematosus (SLE) and put on anti-SLE drugs and antipsychotics, with a favorable evolution.ConclusionsThe chronological relationship between COVID-19 infection, vaccination and the first lupus cerebritis manifestations is highly suggestive, albeit with no certainty, of the potential causal link. We suggest that precautionary measures should be taken to decrease the risk of SLE onset or exacerbation after COVID-19 vaccination, including a systematic COVID-19 testing before vaccination in individuals with specific predisposition.