Objective This study was focused on the association between neutrophil extracellular traps (NETs) and interstitial lung disease (ILD) in patients with dermatomyositis (DM).Methods Thirty six patients who satisfied the Bohan & Peter criteria for DM were recruited to this study,among whom 19 were complicated with ILD.Forty seven age and sex matched healthy Chinese volunteers were selected to be control subjects.The plasma samples of these patients were tested for the formation and degradation of NETs.Results DM plasma induced more NETs formation than control plasma did [(246±93) RFUs vs (192±53) RFUs,P=0.002].Compared to control,DM plasma exhibited a signficantry decreased ability to degrade NETs.Further mere,compared with DM patients without ILD (DMNL),DM patients with ILD (DML) could not degrade NETs completely [(83±13)％ vs (59±21)％,P＜0.01].All four DM patients with subacute ILD exhibited a significantly lower ability to degrade NETs than patients with chronic or asymptomatic ILD [(36±14)％ vs (65±19)％,P=0.0139].Conclusion These data show that more NETs formation is induced by plasma and DML fails to completely degrade NETs.These suggest that NETs may play a role in the pathogenesis of DM and DM-associated ILD.

Objective To identify clinical features and risk factors in adult dermatomyositis (DM) with calcinosis.Methods Four hundred and eighty patients' clinical data were collected.The correlation between calcinosis and no calcinosis in adult DM were calculated by t test,x2 test and Mann-whitney U test.Multifactor logistic regression model was established to analyze independent factors for adult DM with calcinosis.Results Calcinosis occurred in 22 cases among these 480 patients with DM.The incidence of adult DM with calcinosis was 4.6％.Calcinosis was most common in the extremities and trunks.Patients with calcinosis had a longer disease duration [48 (24,120) months vs 10 (3,24) months,U=1993,P=0.000)] and more myothenia (95.5％ vs 76.9％,x2=4.192,P=0.038),panniculitis (9.1％ vs 0.4％,P=0.011),periungual erythematosus (22.7％ vs 5.89％,x2=7.044,P=0.008),skin ulcer (50.0％ vs 5.2％,x2=55.767,P=0.000),Raynaud's phenomenon (27.5％ vs 8.1％,x2=3.956,P=0.047).The anti-NXP2 antibody (27.3％ vs 3.9％,x2=19.416,P=0.000) and antiMDA5 antibody (31.8％ vs 12.9％,x2=4.851,P=0.028) were more frequently found in patients with calcinosis.Multi-factor logistic regression showed that anti-NXP2 antibody [OR=10.899,95％CI (2.593,45.816),P=0.001],long diseases duration [OR=1.105,95％CI(1.008,1.021),P=0.000] and skin ulcer [OR=31.585,95％CI(10.683),93.387,P=0.000] were risk factors for adult DM with calcinosis.Conclusion The incidence of calcinosisis in adult DM is 4.5％ in our cohort.Patients with calcinosis are adistinct clinical subset of adult DM.Long disease duration,skin ulcer and anti-NXP2 positive are independent risk factors for adult DM with calcinosis.

Objective:To determine the serum levels of chemokine CCL27 and its clinical relevancein patients with dermatomyositis (DM).Methods:The serum CCL27 levels of 58 DM patients, 21 polymyositis (PM) patients, 20 systemic lupus erythematosus (SLE) patients and 31 healthy controls were measured by enzyme linked immunosorbent assay (ELISA). The score of disease activity was measured by two physicians-based on the myositis disease activity assessment tool (MDAAT). Its correlation with serum levels of CCL27 was analyzed. The difference between multiple groups were compared using analysis of variance (ANOVA) and t test, and the relevance was analyzed using Spearman correlation analysis and generalized method of moments (GEE) model. Results:Theserum level of CCL27 in DM patients (178±49) pg/ml was significantly higher than PM (110±40) pg/ml, SLE (141±46) pg/ml and healthy controls (137±38) pg/ml ( F=14.192, P<0.01). Crosssectional analysis showed that the serum CCL27 levelwaspositively correlated with global disease activity ( r=0.301, P=0.022) andskin disease activity ( r=0.493, P<0.01). Patients with V sign had higher serum CCL27 levels (191±52) pg/ml than the patients without (153±33) pg/ml ( t=2.839, P<0.01). Patients with holster sign had higher serum CCL27 levels (196±58) pg/ml than the patients without (168±41) pg/ml ( t=2.176, P=0.034). Follow-up study also found that CCL27l evels were positively correlated with global disease activity ( β=0.031, P=0.042) and skin disease activity ( β=0.032, P<0.01). Conclusion:The serum CCL27 levels are increased in patients with DM and can reflect the skin disease activity. The results of this study suggest that CCL27 may be a marker for cutaneous damage and monitoring of therapeutic effect.