Frequency of ANA/DFS70 autoantibodies in Colombian patients with undifferentiated connective tissue disease

Abstract

The objective was to describe the clinical characteristics and the frequency of the ANA/DFS70 autoantibodies in patients affected by undifferentiated connective tissue disease (UCTD) in a tertiary hospital in Colombia. This descriptive cross-sectional study enrolled patients who fulfilled the classification criteria for UCTD. ANAHEp- 2 test and the modified assay for ANA/DFS70 autoantibodies were performed through the indirect immunofluorescence technique. Erythrocyte sedimentation rate, C-reactive protein, rheumatoid factor, and the antibodies to anti-extractable nuclear antigens, DNA, phospholipids (IgG, IgM, IgA), and cyclic citrullinated peptide were also evaluated. Fifty-three patients were studied; 42/53 (79%) tested positive for ANA and 5/42 (11.9%) for ANA/DFS70 antibodies with a dense fine speckled fluorescent pattern (AC-2) in ANA HEp-2 test that was confirmed by a modified HEp-2-DFS70 assay. Patients had arthralgia (87%, n=47), non-erosive arthritis (66%, n=34), xerostomia (64%, n=34), xerophthalmia (42%, n=22), and Raynaud’s phenomenon (17%, n=9). Arthralgia, xerophthalmia, xeroderma, and absence of disease evolution to a specific disease over five years were more frequent in patients with a positive result for the anti-DFS70 antibodies. The ANA/DFS70 autoantibodies were more frequent in patients with UCTD compared to other rheumatic diseases for which they were initially evaluated. More studies are required to support the predictive role of this antibody to the absence of progression to a well-defined connective tissue disease.

Dense fine speckled nuclear immunofluorescence: A mildly reassuring antinuclear antibody pattern meriting consideration

“…Anti‐DFS70 antibodies are thought to have this function. 34 Infantino et al 33 evaluated 91 patients diagnosed with UCTD, documenting a high prevalence of anti‐DFS70 antibodies in this study group (13.3%). Given that the presence of these antibodies is not typical for CTDs, anti‐DFS70 appears to be a reliable marker for UCTD and indicates a low risk of specific CTD developing.…”

“…Therefore the search for serological markers that will help exclude the diagnosis of UCTD with a high risk of progression to CTD has been undertaken. Anti‐DFS70 antibodies are thought to have this function 34 . Infantino et al 33 evaluated 91 patients diagnosed with UCTD, documenting a high prevalence of anti‐DFS70 antibodies in this study group (13.3%).…”

“…UCTD is most commonly manifested by pain and inflammation of the joints 33 . The prevalence of anti‐DFS70 antibodies among patients with UCTD is estimated at 8%–40% and they usually coexist with antibodies typical for specific CTDs 34 …”

“…33 The prevalence of anti-DFS70 antibodies among patients with UCTD is estimated at 8%-40% and they usually coexist with antibodies typical for specific CTDs. 34 It has been proven that 1/3 of patients with UCTD will develop fully symptomatic CTD within 5 years from the onset of the first manifestations. Therefore the search for serological markers that will help exclude the diagnosis of UCTD with a high risk of progression to CTD has been undertaken.…”

Anti-DFS70 antibodies are more prevalent in UCTD and Asian SLE patients

“…Infantino's study concluded that patients with UCTD who are positive for anti-DFS70 antibodies are less likely to progress to CTD based on the signi cantly higher detection rate of anti-DFS70 antibodies in patients with UCTD (13.3%, 12/91) compared to CTD (2.6%, 10/384) [15]. Another article supported this conclusion, reporting only 1 in 5 UCTD patients with anti-DFS70 differentiated into SLE in 5 years [39]. However, due to the paucity of literature and data on related studies, the protective effect of anti-DFS70 in UCTD patients remains to be con rmed by multi-center, inter-regional and inter-ethnic long-term follow-up studies.…”