Abstract
Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect the central nervous system, leading to a broad and heterogeneous range of neuropsychiatric symptoms, such as depression, cognitive impairment, and psychosis, that often present diagnostic challenges.
We present a rare case of a 47-year-old female with a long-standing SLE diagnosis who showed an unusual incidence of late-onset psychosis. The patient, who had been in remission for an extended period using venlafaxine to manage depression and anxiety, presented with delusions of jealousy and persecution, as well as irritability and behavioral changes. Despite having a long history of SLE without showing any symptoms of active disease and not using steroids, the patient primarily complained of psychiatric issues. A comprehensive psychiatric and medical evaluation, including serological and imaging studies, was conducted to explore potential mechanisms underlying the atypical neuropsychiatric manifestation. The patient responded favorably to antipsychotic treatment, with a notable decrease in aggressive behavior and remission of psychotic symptoms.
This case reflects the diagnostic uncertainty that may arise when psychosis occurs in a patient with SLE and underscores the need for individualized and integrative approaches in such clinical contexts, given the broad spectrum of neuropsychiatric systemic lupus erythematosus (NP-SLE) and the often challenging nature of differential diagnosis.

Key words: Neuropsychiatric Lupus, Psychosis, Systemic Lupus Erythematosus