Clinical value of autoantibodies for lupus myelitis and its subtypes: A systematic review

We conducted a systematic review to investigate the clinical value of clinical characteristics and autoantibodies, especially lupus-specific antibodies, for lupus myelitis and its subtypes. We searched PubMed, EMBASE, and ICHUSHI without language restrictions for case reports or series of lupus myelitis. We focused on cases reported since 1997, when the revised classification criteria for systemic lupus erythematosus were published. Associations between patient characteristics including autoantibodies and functional outcome, survival, subtypes of myelitis (grey and white matter myelitis), and treatment were examined. We attempted to contact authors to supplement missing information for analysis. Our search identified 224 cases from 105 articles. White matter myelitis predicted favorable function (odds ratio = 15.18; 99% confidence interval, 3.09–151.31; p < 0.0001). Grey matter myelitis was associated with longitudinally extensive transverse myelitis (p < 0.001) and anti-double-stranded DNA (p = 0.003), and tended to be associated with anti-β2-glycoprotein I (p = 0.011). White matter myelitis tended to be associated with optic neuritis and anti-neuromyelitis optica antibodies. Although our study might be susceptible to under-reporting of original cases and selection bias, we aimed to provide a conservative interpretation by setting the statistical significance threshold at p < 0.01. This systematic review confirmed that grey matter myelitis predicted poor functional outcome and was associated with longitudinally extensive transverse myelitis and anti-double-stranded DNA antibodies. White matter myelitis was associated with favorable functional outcomes and may partially represent a complication of neuromyelitis optica.