RESUMEN
To investigate the distribution and clinical significance of nuclear dense fine speckled (DFS) pattern in various diseases. A total of 95 289 patients who received DFS tests at Peking Union Medical College Hospital from January 2019 to December 2020 were included in this study. The results of indirect immunofluorescence assay (IIF) for detection of antinuclear antibody (ANA) were evaluated. The positive rates of ANA and DFS were 39.60% (37 733/95 289) and 1.19% (1 139/95 289) respectively. The positive rate of DFS in ANA-positive patients was 3.02% (1 139/37 733). DFS and ANA positivity were significantly different among different age groups rather than gender. The positivity rate of DFS reached the peak (55.57%, 633/1 139) in young patients between 21-40 years, while positive ANA with negative DFS was mainly observed in patients between 41-60 years (37.26%, 13 636/36 594). Additionally, single ANA-positivity were mainly detected in rheumatology department (59.23%, 18 402/31 066), whereas positive DFS was more common in obstetrics and gynecology department (3.08%, 49/1 593). There were 82.88% (944/1 139) patients with positive DFS diagnosed with non-autoimmune disease (non-AID), and 19.49%(222/1 139) with dermatosis. Positive DFS with higher titer (≥1∶320) was detected more frequently in autoimmune disease (AID) patients (5.13%, 10/195) than in non-AID patients (1.69%, 16/944) ( P<0.05). The DFS pattern is rare in ANA positive patients, which is mainly observed in women between 21-49 years. High titer of DFS is prevalent in AID patients, but positive DFS is detected more in non-AID patients, especially those with dermatosis.
RESUMEN
BACKGROUND: Dense fine speckled (DFS) pattern in antinuclear antibody (ANA) test using indirect immunofluorescence method became to be known recently and it is detected in patients with various chronic inflammatory diseases as well as in healthy individuals. We investigated the relation between DFS pattern and various diseases. METHODS: ANA tests by indirect immunofluorescence method using HEp-2 cell line slide (Kallestad; Bio-Rad, USA) were performed in 2,654 patients for screening of systemic autoimmune diseases. The frequencies of ANA and DFS positivity were analyzed according to sex, age, clinical department and disease. RESULTS: ANA was positive in 13.3% (352/2,654) of the total patients, and the frequency of DFS pattern was observed in 3.8% (101/2,654) of the total patients and in 28.7% (101/352) of the patients with ANA positivity. Higher frequency of DFS positivity was observed in patients referred from Departments of Rheumatology and Nephrology, but there was no difference in the frequencies of DFS positivity among the patients with ANA positivity. The frequency of DFS pattern was higher in seborrheic dermatitis (14.3%), herpes zoster (11.1%), rheumatoid arthritis (16.9%), systemic lupus erythematosus (15.4%) and Sjogren syndrome (14.3%). CONCLUSIONS: The DFS pattern is a frequent finding (about 28% of ANA positivity) in ANA test using indirect immunofluorescence method. Relatively high frequency of DFS pattern was observed in autoimmune diseases, contrary to the previous observations that DFS pattern is not related with autoimmune diseases. Further studies including the confirmation tests of anti-DFS70 are needed for the identification of relation between DFS pattern and particular diseases.