en ایمنی شناسی Immunology گزارش مورد Case Report <div style="text-align: justify;"><span style="font-size:12px;"><span style="font-family:Times New Roman;"><b>Background:</b> Anti-centromere antibodies (ACA) are commonly detected by indirect immunofluorescence (IIF) on HEp-2 cells, typically producing the classic centromere pattern (AC-3). However, discrepancies between IIF and solid-phase immunoassays, such as ELISA, may complicate interpretation.<br> <b>Case Presentation:</b> We report the case of a 75-year-old woman who presented with progressive inflammatory polyarthritis, morning stiffness, dry mouth, photosensitivity, and mild exertional dyspnea. Antinuclear antibody (ANA) testing by IIF on HEp-2 cells demonstrated a multiple nuclear dots pattern (AC-6), with features resembling a CENP-F&ndash;like pattern (AC-14), rather than the typical centromere pattern. By contrast, solid-phase assays, including ELISA and immuno-dot blot, demonstrated anti-centromere antibody reactivity. Additional serologic findings included strong positivity for SSA/Ro60, Ro52/TRIM21, SSB/La, and DFS70 antibodies.<br> <b>Conclusion</b>: This case demonstrates that anti-centromere reactivity detected by solid-phase assays may occur despite the absence of a classic AC-3 pattern on IIF. The interpretation of discordant serologic findings requires careful integration of clinical features with complementary laboratory methods.</span></span></div> Anticentromere Antibody, Indirect Immunofluorescence, Enzyme-Linked Immunosorbent Assay, CENP-F protein, HEp-2 cell, ANA Patterns 0 0 http://mlj.goums.ac.ir/browse.php?a_code=A-10-1140-3&slc_lang=en&sid=1 Mohammadreza Sheikh Sajjadieh mohammad_esfahan@yahoo.com 100319475328460032663 100319475328460032663 Yes MOL Diagnostics Melbourne, Australian Institute of Medical and Clinical Scientists (AIMS) Melbourne, Victoria, Australia Olena Sheikh Sajjadieh sheikhsajjdieh@gmail.com 100319475328460032664 0009-0000-9624-244X No MOL Diagnostics Melbourne, Australian Institute of Medical and Clinical Scientists (AIMS) Melbourne, Victoria, Australia Ghazale Aghababaei aghababaeighaleh@gmail.com 100319475328460032665 0009-0006-1488-6668 No Padtan Danesh Company, Tehran, Iran Mohammad Farzi farzi@ptdlab.com 100319475328460032666 100319475328460032666 No Padtan Danesh Company, Tehran, Iran Abdolsamad Ghorbani info@vahid-lab.com 100319475328460032667 0009-0006-4124-1590 No Laboratory Medicine, Vahid Medical Laboratory, Isfahan, Iran