Psychosis in a Complex Medical Landscape: Diagnostic Challenges Posed by Systemic Lupus Erythematosus, Antiphospholipid Syndrome, Breast Cancer, and Temporal Lobe Resection.

This study aimed to highlight the complex diagnostic process in a patient presenting with a new onset of both psychiatric and neurological signs and symptoms in the context of a complex medical background. A 60-year-old woman presented with psychosis, paranoia, disorientation, and choreiform movements, with a medical history of systemic lupus erythematosus (SLE), antiphospholipid syndrome (APS), active breast cancer, and a recent temporal lobe resection. The differential diagnoses considered included various neuropsychiatric conditions, such as neuropsychiatric SLE, steroid-induced psychosis, chemotherapy-induced neurotoxicity, and paraneoplastic syndrome, as well as primary psychotic disorder. The case illustrates the often inconclusive nature of various investigations, including autoimmune blood panels, magnetic resonance imaging, and electroencephalography, all of which failed to yield a definitive diagnosis. It also underscores the need for a multidisciplinary approach involving psychiatric and medical specialists, alongside regular observation and input from other ward staff, to optimally manage patients with such complex presentations.