Anti-Cytosolic 5′-Nucleotidase 1A in the Diagnosis of Patients with Suspected Idiopathic Inflammatory Myopathies: An Italian Real-Life, Single-Centre Retrospective Study

Background: Anti-cytosolic 5′-nucleotidase 1A (anti-cN1A) antibodies were proposed as a biomarker for the diagnosis of inclusion body myositis (IBM), but conflicting specificity and sensitivity evidence limits its use. Our study aimed to assess diagnostic accuracy anti-cN1A in cohort patients who underwent line immunoassay suspected idiopathic inflammatory myopathies (IIM). We also assessed agreement between two testing procedures: (LIA) enzyme-linked (ELISA). Materials methods: collected retrospective clinical serological data 340 antibody assay using LIA (EUROLINE Autoimmune Inflammatory Myopathies 16 Ag et cN-1A (IgG) immunoassay) verification with an ELISA (Euroimmun Lubeck, Germany). Results: The serum samples 20 (5.88%) (15 females, 5 males, mean age 58.76 ± 18.31) tested positive LIA, only out twenty diagnosed IBM. Seventeen (median IQR, 2.9 (1.9–4.18)). Conclusions: suggests excellent concordance detecting antibodies. may be rapid useful adjunct, it could even replace cN1A assay. However, high prevalence diseases other than IBM our anti-cN1A-positive did not allow us consider specific