High levels of serum hyaluronic acid in adults with dermatomyositis.

UNLABELLED BACKGROUND / OBJECTIVES: Hyaluronic acid (HA) is rarely described in dermatomyositis (DM). Thus, we determined any clinical association of serum levels of hyaluronic acid (HA) in patients with dermatomyositis (DM). MATERIALS AND METHODS This cross-sectional single-center analysis 75 DM and 75 healthy individuals, during the period from January 2012 to July 2013. An anti-HA antibody assay was performed using specific ELISA/EIA kits, according to the manufacturer's protocol. RESULTS The patients with DM and control subjects had comparable demographic distributions (p>0.05). The median time duration between disease diagnosis and initial symptoms was 6.0 [3.0-12.0] months, with a median DM disease duration of 4.0 [1.0-7.0] years. The median level of serum HA was significantly increased in patients with DM compared to the control group [329.0 (80.0-958.0) vs. 133.0 (30.0-262.0) ng/mL, respectively; p<0.001]. Additional analysis involving patients with DM showed that the serum level of HA did not correlate with age, duration between disease diagnosis and initial symptoms, disease duration, disease status, serum muscle enzyme levels or cumulative prednisolone dose (p>0.05). Serum HA also did not correlate with gender, ethnicity, auto-antibodies or drug use (p>0.05), but did correlate with cutaneous features, such as photosensitivity (p=0.001), "shawl" sign (p=0.018), "V-neck" sign (p=0.005) and cuticular hypertrophy (p=0.014). CONCLUSIONS A high level of serum AH was observed in DM compared to healthy individuals. In DM, HA did not correlate to demographic, auto-antibodies and therapy parameters. However, HA correlated specifically with some cutaneous features, suggesting that this glycosaminoglycan could be involved in modulating cutaneous inflammation in this population. More studies are necessary to understand the correlation between AH and patients with DM.