Low serum S100A6 levels are associated RP-ILD risk in anti-MDA5-positive dermatomyositis.

Background: Anti-MDA5-positive dermatomyositis (anti-MDA5-DM) is a rare autoimmune disease that often leads to rapid-progressive interstitial lung disease (RP-ILD). The lack of effective prediction and treatment methods makes RP-ILD a major risk factor for death in patients with this condition. S100A6 is a member of the S100 Ca2 + - binding protein family, which plays important roles in inflammation, tumor, injury, and fibroblast reparation. This study aims to explore the correlation between serum S100A6 and RP-ILD in anti-MDA5-DM, and to determine whether S100A6 can be used as a specific biomarker to predict RP-ILD.

Methods: The authors enrolled 80 participants, including 20 healthy volunteers, 20 patients with anti-synthase syndrome, and 40 patients with anti-MDA5-positive dermatomyositis. Serum samples were collected and the levels of S100A6 were measured using ELISA. Logistic regression was used to analyze the relationship between serum S100A6 levels and RP-ILD, along with other clinical and laboratory parameters. 

Results: Serum S100A6 levels were significantly lower in anti-MDA5-DM patients with RP-ILD than those without RP-ILD (odds ratio:0.393 (95% CI, 0.164-0.943, p = 0.036)). High serum S100A6 level was found to be a protective factor for RP-ILD. This study shows that high serum S100A6 level may be a protective factor for RP-ILD in anti-MDA5-DM patients. Serum S100A6 may be used as a specific biomarker to predict whether RP-ILD occurs in anti-MDA5-DM. Key Points • This research discovers and reports a biomarker (S100A6) for distinguishing potential RP-ILD in Anti-MDA5 positive dermatomyositis.