The antinuclear antibody HEp-2 indirect immunofluorescence harmonization and competency assessment program of the Society for Clinical Microbiologists of Türkiye: analysis of 7-year assessment results

Abstract

Introduction Accurate and harmonized antinuclear antibody HEp-2 indirect immunofluorescence (IIF) reporting is essential for reliable communication between laboratories and clinicians. In T & uuml;rkiye, a national online HEp-2 IIF competency assessment program has been operating since 2018, with 3 runs per year and participation of individual users representing clinical laboratories nationwide. The program evaluates the performance of participants and identifies training and reporting needs.Methods Between 2018 and 2025, 21 runs were conducted; the accuracy of competent-level and expert-level fluorescence pattern identification was analyzed. Twenty-six to 64 participants took part in each run. Since 2021, reflex test recommendations have been incorporated.Results The competent-level fluorescence patterns most accurately identified were AC-1, AC-3, AC-6/7, AC-8/9/10, AC-11/12, and AC-15/16/17, while AC-0 and AC-2/30 showed less than 80% accuracy in at least 1 run. Among expert-level patterns, accuracy was highest for pattern AC-27 and lowest for pattern AC-29, with low rates for AC-5, AC-6, AC-15, and AC-20. Reflex test recommendations were generally accurate (75.6%-100%).Discussion The results revealed good performance for many competent-level nuclear and cytoplasmic patterns and satisfactory reflex test recommendations. Persistent challenges were recognized, however, for patterns AC-29, AC-5, AC-20, and AC-0. Competency self-assessment, combined with collective performance evaluation, may provide insight for the harmonization of HEp-2 IIF reporting and improvement of laboratory-clinician collaboration.