Interstitial Lung Disease in Systemic Sclerosis: A Single-center Retrospective Analysis

Background: Systemic sclerosis (SSc) is a systemic autoimmune disease characterized by microangiopathy, inflammation, fibrosis. Interstitial lung disease (ILD) is common among SSc patients. Objective: This study aims to define the clinical, laboratory, and serologic characteristics of SSc patients with ILD and to present the frequency of chest computed tomography features. Methods: Two hundred twenty-six SSc patients who applied to the Rheumatology Department between January 2007 and August 2019 were retrospectively examined. A total of 100 SSc patients with ILD (44.2%) were determined. Clinical, laboratory, and serological features of SSc patients with and without ILD were compared. Results: Both groups had similar characteristics in terms of age and sex. The duration of disease (p=0.001) and follow-up time (p=0.001) were longer in SSc patients with ILD. Multivariable logistic regression analysis indicated that the duration of disease (OR: 1.06 (1.01-1.13), p=0.029), presence of gastrointestinal system involvement (OR: 3.29 (1.28-8.46), p=0.013) and anti-SCL70-positivity (OR: 6.04 (2.35-15.49), p <0.001) were associated with ILD. There was an inverse relationship between Anti-CENP-B positivity and the presence of ILD (p=0.001). The assessment regarding the chest computed tomography characteristics of interstitial pneumonia patterns were as follows: 82.5% non-specific interstitial pneumonia, 14.4% usual interstitial pneumonia, and 2.1% desquamative interstitial pneumonia. The most frequent abnormal findings included ground-glass opacification (88.7%), reticulation (64.9%), traction bronchiectasis (57.7%), septal thickening (52.6%) and honeycombing (28.9%). Conclusion: We have shown a relationship between anti-SCL70, disease duration, gastrointestinal system involvement, and ILD in SSc patients.