Psychosis is a rare manifestation of Neuropsychiatric Systemic Lupus Erythematosus (NPSLE). Current guidelines do not recommend the use of Antinuclear Antibodies (ANA) testing in the assessment of patients with psychosis. This study was undertaken to determine the prevalence of NPSLE in patients with psychosis who have had positive ANA. This study is a retrospective review of patients admitted to the mental health service of two metropolitan tertiary referral centers diagnosed with psychosis who had been tested for ANA.

There were 10,205 mental health admissions with diagnoses of psychosis representing 4766 individual patients, 911 (19%) patients were tested for ANA, 135 (15%) of those tests returned a positive result with a titer ≥1:160. The mean follow‐up time was 47 ± 26 months. At discharge, four patients met the 2019 ACR/EULAR criteria for SLE, two of whom met the criteria for NPSLE. Both of these patients had other manifestations of SLE. This gave an NPSLE prevalence of 1.5% (2/135) amongst patients with positive ANA and 0.2% (2/911) among all patients who underwent ANA testing.

The prevalence of NPSLE in patients with psychosis and positive ANA was low at 1.5%. The low rate of clinically significant positive results would argue against routine testing for ANA in psychosis patients.