Objective: Our aim was to evaluate the results of indirect fluorescent antibody (IFA) method performed with the specimens sent to our medical microbiology laboratory for anti-nuclear antibody (ANA) investigation from the rheumatology clinic.

Methods: ANA test results of 2171 patients with an autoimmune disease-suspect between January 2021 and January 2022 in the Medical Microbiology laboratory were included in the study. The serums were analyzed by IFA technique (Hep 20-10, Euroimmun AG, Lübeck, Germany) after diluting by 1/100 for antinuclear antibody.

Results: Of the 2171 patient samples, 1808 (83.3%) belonged to female patients and 363 (16.7%) belonged to male patients. Antinuclear antibody positivity was detected in 41.2% (n=894) of specimens at various titers and patterns. Among ANA-positive patients, the common fluorescence patterns were 312 (34.9%) nuclear granular, 188 (21%) homogeneous, 160 (17.9%) nucleolar, 69 (7.7%) homogeneous+granular, 37 (4.2%) granular+nucleolar, 35 (3.9%) centromere, 11 (1.2%) homogeneous+nucleolar, 17 (1.9%) nuclear dot, 14 (1.6%) nuclear membrane.

Conclusion: The data of our study showed that the rate of ANA positivity was high in our region and the most common patterns were granular, homogeneous and nucleolar in accordance with the literature.