Ayaydin, ZeynepOzcan, NidaMermutluoglu, CigdemAtmaca, SelahattinTekin, Ali Cem2025-06-192025-06-1920251302-00722147-2688https://doi.org/10.4274/haseki.galenos.2025.9879https://hdl.handle.net/20.500.12514/8936Aim: Coronavirus disease-2019 (COVID-19) has been suggested to trigger the production of autoimmune antibodies and contribute to the development of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis. This study aims to investigate the presence of ANCA among COVID-19 patients. Methods: This cross-sectional, prospective analysis included 200 COVID-19 patients with positive polymerase chain reaction test results for severe acute respiratory syndrome-coronavirus-2 and no history of autoimmune disease, recruited between June 2021 and November 2022. The control group included 50 age-matched healthy blood donors. The ANCA profile was assessed using the indirect immunofluorescence assay method with the EUROPLUS Granulocyte Mosaic EUROPattern test kit (EUROIMMUN, Germany) on sera samples of the patient and control groups. Results: Perinuclear ANCA (p-ANCA) was detected in 12 of 200 COVID-19 patients (6.0%) and cytoplasmic ANCA (c-ANCA) was detected in 15 of 200 patients (7.5%). No ANCA positivity was observed in the control group (0/50). ANCA positivity among COVID-19 patients (27 of 200, 13.5%) was statistically significantly higher than in the control group (p<0.05). ANCA positivity was significantly higher in intensive care unit (ICU) patients (21 of 77, 27.3%) compared to non-ICU patients (6 of 123, 4.9%) (p<0.05). Conclusion: ANCA presence in ICU patients supports the hypothesis that COVID-19 triggers ANCA synthesis and contributes to disease severity.en10.4274/haseki.galenos.2025.9879info:eu-repo/semantics/openAccessCovid-19Anti-Neutrophil Cytoplasmic AntibodiesVasculitisIndirect Immunofluorescence AssayArticle6311923N/AQ3WOS:0014840590000012-s2.0-105005103536