Interstitial lung disease in systemic sclerosis: From immunopathogenesis to treatment

Interstitial lung disease (ILD) is a pulmonary involvement that is commonly manifested in systemic sclerosis (SSc) patients. The immunopathogenesis of SSc-ILD involves several mechanisms, including microvascular injury, alveolar epithelial cell defect, inflammation, genetics, epigenetics, telomeres, telomerase and inflammasome, which result in lung fibrosis. Detection of ILD should be performed in every SSc patient by using high-resolution chest tomography (HRCT) scan of the thorax, in addition to evaluation by pulmonary function tests. When ILD is discovered, the physician might start treatment considering factors such as the extent of the lesion, progressivity of the disease, prognosis and drug toxicity. The current guideline recommends cyclophosphamide, mycophenolate mofetil and nintedanib as the initial choices for SSc-ILD treatment. Other agents such as biologic immunotherapies, haematopoietic stem cell transplantation and lung transplantation could be an option if the disease becomes progressive.