Cytokine profiles in polymyositis and dermatomyositis complicated by rapidly progressive or chronic interstitial lung disease

• Published in: Rheumatology (Oxford, England) Vol. 53; no. 12; pp. 2196 - 2203
• Main Authors: Gono, Takahisa, Kaneko, Hirotaka, Kawaguchi, Yasushi, Hanaoka, Masanori, Kataoka, Sayuri, Kuwana, Masataka, Takagi, Kae, Ichida, Hisae, Katsumata, Yasuhiro, Ota, Yuko, Kawasumi, Hidenaga, Yamanaka, Hisashi
• Format: Journal Article
• Language: English
• Published: England 01.12.2014
• Subjects: Adult; Chronic Disease; Cytokines - blood; Dermatomyositis - complications; Dermatomyositis - immunology; Disease Progression; Female; Humans; Interleukin-6 - blood; Interleukin-8 - blood; Lung Diseases, Interstitial - etiology; Lung Diseases, Interstitial - immunology; Male; Middle Aged; Polymyositis - complications; Polymyositis - immunology; Prognosis; Retrospective Studies; Severity of Illness Index; Tumor Necrosis Factor-alpha - blood; polymyositis; dermatomyositis; TNF-α; IL-8; interstitial lung disease; IL-6
• ISSN: 1462-0324; 1462-0332
• DOI: 10.1093/rheumatology/keu258

PM and DM are often complicated by interstitial lung disease (ILD). In this study we aimed to evaluate various serum cytokines in patients with PM/DM with ILD so as to clarify the differences in pathophysiology between anti-melanoma differentiation-associated gene 5 antibody-associated ILD (anti-MDA5-ILD) and anti-aminoacyl tRNA synthetase antibody-associated ILD (anti-ARS-ILD). We evaluated the serum cytokine profiles of 38 patients with PM/DM and compared the cytokine profiles of the non-ILD and ILD subsets as well as the anti-MDA5-ILD and anti-ARS-ILD subsets. The myositis intention-to-treat activity index score, which indicates whole disease activity, significantly correlated with serum IL-6, IL-8, TNF-α and IP-10. These cytokine levels were significantly higher in the ILD subset than the non-ILD subset and were lower in the ILD subset following treatment. By multivariate analysis, TNF-α was the most significant cytokine [P = 0.0006, odds ratio (OR) 1.4, CI 1.1, 2.2] associated with PM/DM with ILD. IL-8 levels were significantly higher in anti-MDA5-ILD than in anti-ARS-ILD, although IL-6, TNF-α and IP-10 levels were high in both subsets. IL-8 was the most significant cytokine (P = 0.0006, OR 1.5, CI 1.1, 3.0) associated with anti-MDA5-ILD by multivariate analysis. Moreover, the ratio of IL-4 to IFN-γ was lower in anti-MDA5-ILD than in anti-ARS-ILD. IL-6, IL-8, TNF-α and IP-10 are associated with global disease activity in PM/DM. These cytokine levels were high, especially in the ILD subset. Serum IL-8 levels and the balance between IL-4 and IFN-γ may contribute to the differences in pathophysiology between anti-ARS-ILD and anti-MDA5-ILD.