Autoantibodies involved in neuropsychiatric manifestations associated with systemic lupus erythematosus: a systematic review

Neuropsychiatric systemic lupus erythematosus (NPSLE) is one of the most important manifestations of SLE, and includes a variety of clinical manifestations, classified by the American College of Rheumatology in 19 different neuropsychiatric syndromes. To date, more than 116 antibodies have been reported in SLE and at least 20 of them, including 11 brain-specific and 9 systemic antibodies, have been controversially associated with NPSLE. To systematically review the available evidence, to define the association between the above antibodies and NPSLE as a whole and with the 19 neuropsychiatric syndromes associated with SLE, by strictly applying the American College Rheumatology case definitions. Medline reports published between 1999 and 2013 investigating the association between antibodies and NPSLE were included. Whenever possible, associations between antibodies and both NPSLE as a whole and with the 19 syndromes were analysed. This systematic review is based on available data from more than 8,000 patients and controls from 42 studies analysing antibodies and NPSLE. Nineteen studies analysed the role of antiphospholipid antibodies (aPL), 11 focused on anti-ribosomal-P protein antibodies and 5 on anti-N-Methyl-d-Aspartate receptor antibodies. Two studies analysed, respectively, antibodies to aquaporin-4 and VH4-34 encoded antibodies. Given the multitude of clinical manifestations related to NPSLE, a single biomarker failed to be reliably associated with all neuropsychiatric events. Our findings provide evidence that aPL, mainly the lupus anticoagulant, and anti-ribosomal P antibodies are significantly associated with specific manifestations of neuropsychiatric disease attributed to SLE, namely, cerebrovascular events and psychosis, respectively.