{
  "abstract": "Objectives To assess the diagnostic performance of anti-dsDNA and anti-ribosomal P antibodies in cerebrospinal fluid (CSF) for identifying inflammatory neuropsychiatric lupus (NPSLE) with central nervous system (CNS) involvement.Methods We included adults (>18 years) who underwent CSF testing for anti-ribosomal P and/or anti-dsDNA antibodies during evaluation of neuropsychiatric symptoms at a tertiary referral center in Mexico (Jan 2012-Jun 2024). Based on final diagnosis, patients were categorized as: (1) NPSLE, per ACR/EULAR 2019 SLE criteria and 1999 ACR NPSLE nomenclature; (2) secondary neuropsychiatric conditions in SLE (SN-SLE), attributing symptoms to non-SLE causes; or (3) non-autoimmune neuropsychiatric disease (NP-non-AI). Patients with incomplete records or other autoimmune neurologic conditions were excluded. Clinical data, disease activity (SLEDAI-2K and a modified version excluding neurologic items), chronic damage (SDI) and laboratory data, including serum and CSF antibodies measured by ELISA, were documented within 30 days of CSF testing. For inflammatory CNS-NPSLE analyses, we excluded patients with stroke, peripheral/autonomic NPSLE and minor neuropsychiatric manifestations as excluded by Ainiala et al. Correlations were assessed with Spearman’s coefficient. Diagnostic performance was evaluated using ROC curves, AUCs, Youden index-based cutoffs and standard diagnostic metrics.Results Among 85 patients, 25 were classified as NPSLE, 39 as SN-SLE and 21 as NP-non-AI. NPSLE patients were younger, had shorter disease duration, higher systemic activity and significantly elevated CSF levels of anti-dsDNA ( table 1). Strong correlations were observed between serum and CSF levels of anti-dsDNA (rho=0.828, p<0.001) and anti-ribosomal P antibodies (rho=0.920, p<0.01), as well as significant correlations between CSF antibody levels and clinical variables (figure 1). For the analysis of inflammatory CNS NPSLE, we excluded stroke (n=5), cognitive dysfunction (n=1), peripheral NPSLE (n=3) and PRES (n = 1). For inflammatory CNS NSPLE, a CSF anti-dsDNA threshold >27 IU/mL or >2.8 x the serum upper limit of normal yielded an AUC of 0.963 (Sens: 99.9%, Spe: 88.9%, LR+ 9.01). Similarly, a CSF/serum anti-ribosomal P ratio >1.8 had an AUC of 0.975 (Sens: 99.9%, Spe: 87.5%, NPV 99.9) (table 2).Abstract S3:05 Table 1Clinical and laboratory characteristics of the cohortAbstract S3:05 Table 2Diagnostic performance of SCF anti-dsDNA and anti-ribosomal P antibodies for the diagnosis of predominantly inflammatory NPSLE with central nervous system involvementAbstract S3:05 Figure 1Correlations of antibody levels in serum and cerebrospinal fluidConclusions CSF anti-dsDNA and anti-ribosomal P antibodies may serve as potential biomarkers for the diagnosis of inflammatory NPSLE with CNS involvement.",
  "authors": [
    {
      "affiliations": [
        "Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico"
      ],
      "name": "Marlon Sandino"
    },
    {
      "affiliations": [
        "Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico"
      ],
      "name": "Erik Cimé-Aké"
    },
    {
      "affiliations": [
        "Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico"
      ],
      "name": "Jonathan Campos-Guzmán"
    },
    {
      "affiliations": [
        "Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico"
      ],
      "name": "Eduardo Briones-García"
    },
    {
      "affiliations": [
        "Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico"
      ],
      "name": "Emilio Lazarini"
    },
    {
      "affiliations": [
        "Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico"
      ],
      "name": "Carlos Núñez-Álvarez"
    },
    {
      "affiliations": [
        "Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico"
      ],
      "name": "Hilda Fragoso-Loyo"
    }
  ],
  "title": "S3:05 Diagnostic performance of cerebrospinal fluid antibodies in inflammatory neuropsychiatric lupus with central nervous system involvement",
  "uid": "c37d5240-6c59-5240-9b50-f68ee557dfdb"
}