{
  "abstract": "Objectives Systemic lupus erythematosus (SLE) is a complex autoimmune disease where the search for reliable biomarkers to monitor disease activity and clinical manifestations remains relevant. Calprotectin, a protein released by activated neutrophils, represents a promising candidate for this role, given the importance of neutrophilic inflammation and NETosis in SLE pathogenesis. The aim of this study was to evaluate serum calprotectin levels in SLE patients and analyze its association with disease activity and specific clinical manifestations.Methods The study included 53 patients with a confirmed diagnosis of SLE, with a disease duration of 6 years [1; 12] and an SLEDAI-2K score of 10 [6; 18] points. A control group of 40 generally healthy individuals, matched by sex and age, was selected. The concentration of calprotectin in blood serum was determined by enzyme-linked immunosorbent assay (ELISA) using the reagent kit Bühlmann Laboratories AG (Switzerland) according to the manufacturer’s instructions.Results Calprotectin levels were significantly higher in SLE patients compared to the control group (3.7 [2.1; 7.4] vs. 2.36 [1.77; 3.51], p=0.004). A significant increase in calprotectin concentration was observed in patients with SLEDAI-2K greater than or equal to 6 compared to those with low disease activity (5.61 [2.32; 8.28] vs. 2.36 [1.56; 3.72], p=0.034). Analysis of clinical and laboratory manifestations revealed statistically significant associations between elevated calprotectin levels and the presence of arthritis and increased C-reactive protein (CRP) values (7.4 [3.04; 9.76] versus 3.16 [1.89; 6.22], p=0.020 and 8.59 [6.97; 9.8] versus 3.05 [1.93; 6.27], p=0.002, respectively).Conversely, patients with leukopenia and neutropenia showed lower levels of calprotectin (1.98 [0.98; 2.43] vs. 5.58 [2.56; 7.7], p=0.010 and 2.06 [1.11; 3.05] vs. 6.08 [2.99; 8.75], p=0.0001, respectively). No significant association was found between calprotectin and current therapy or immunological parameters.Conclusions This study demonstrated that serum calprotectin is a significant marker associated with SLE activity and specific clinical phenotypes, particularly arthritis and systemic inflammation. This confirms the important role of neutrophil-mediated immunity in SLE pathogenesis.",
  "authors": [
    {
      "affiliations": [
        "V. A. Nasonova Research Institute of Rheumatology, Moscow, Russia"
      ],
      "name": "Kamila Nurbaeva"
    },
    {
      "affiliations": [
        "V. A. Nasonova Research Institute of Rheumatology, Moscow, Russia",
        "Russian Medical Academy of Continuing Professional Education,Department of Rheumatology, Moscow, Russia"
      ],
      "name": "Tatiana Reshetnyak"
    },
    {
      "affiliations": [
        "V. A. Nasonova Research Institute of Rheumatology, Moscow, Russia"
      ],
      "name": "Anastasiia Shumilova"
    },
    {
      "affiliations": [
        "V. A. Nasonova Research Institute of Rheumatology, Moscow, Russia"
      ],
      "name": "Maria Cherkasova"
    },
    {
      "affiliations": [
        "V. A. Nasonova Research Institute of Rheumatology, Moscow, Russia",
        "Russian Medical Academy of Continuing Professional Education,Department of Rheumatology, Moscow, Russia"
      ],
      "name": "Aleksandr Lila"
    }
  ],
  "title": "PO:02:042 Serum calprotectin as a marker of disease activity and specific clinical manifestations in systemic lupus erythematosus",
  "uid": "0fd80069-6f4a-51ef-8982-79227e7ea134"
}