Association of antiphosphatidylserine/prothrombin antibodies with neuropsychiatric systemic lupus erythematosus

Neuropsychiatric manifestations in patients with systemic lupus erythematosus (SLE) are well-recognized symptoms although the pathophysiology of neuropsychiatric SLE (NPSLE) is unclear. Since an association with antiphospholipid antibodies has been reported, we examined the prevalence of antiphosphatidylserine–prothrombin antibodies (anti-PS/PT Abs), lupus anticoagulant (LA), anticardiolipin/β2-glycoprotein I antibodies (anti-β2-GPI Abs), and antiribosomal P protein antibodies (antiribosomal P Abs) in 68 SLE patients and analyzed their associations with neuropsychiatric manifestations. The prevalence of LA was significantly higher in the patients with neuropsychiatric (NP) features than those without NP features (P < 0.02). The levels of anti-PS/PT antibody were also significantly higher in the patients with NP features than those without NP features (P < 0.01). The results indicate that LA positivity and higher levels of anti-PS/PT antibody can be predictive markers for NPSLE.