Neuropsychiatric Systemic Lupus Erythematosus Presenting With Striatal Lupus Encephalitis and Catatonia: A Multidisciplinary Diagnostic Challenge.

Neuropsychiatric lupus represents one of the most complex and heterogeneous manifestations of systemic lupus erythematosus (SLE). Presentations may include cognitive dysfunction, mood disorders, psychosis, seizures, and movement disorders, often mimicking primary neurological or psychiatric conditions. We report the case of a woman with established SLE who developed acute behavioural change, cognitive decline, and psychomotor agitation progressing to catatonia. Neuroimaging demonstrated symmetrical basal ganglia abnormalities with associated cortical and basal ganglia microinfarcts. Extensive investigation excluded infectious, embolic, and primary neurodegenerative causes. The clinical picture was ultimately attributed to striatal lupus encephalitis, a rare manifestation of neuropsychiatric SLE (NPSLE). She was treated with high-dose corticosteroids and intravenous cyclophosphamide with subsequent clinical improvement, while catatonic symptoms responded rapidly to benzodiazepine therapy. Repeat MRI showed partial regression of basal ganglia abnormalities but new microinfarcts. This case highlights the evolving nature of NPSLE, the importance of multidisciplinary collaboration, and the need to consider autoimmune mechanisms in atypical neuropsychiatric presentations.