Sequential approach to interstitial lung disease: An autoimmune perspective

Interstitial lung disease occurs with high frequency as an initial or late manifestation of multiple rheumatic diseases, including systemic sclerosis, idiopathic inflammatory myopathies, rheumatoid arthritis, systemic lupus erythematosus, primary Sjögren's syndrome and antineutrophil cytoplasmic antibody-associated vasculitis. Thus, the rheumatologist must be clear about certain concepts of pneumology, including the evaluation of lung function tests, the approach to radiological patterns observed on high-resolution computed tomography of the chest, and concepts such as interstitial pneumonia with autoimmune features. In this article, we present our approach to patients with interstitial lung disease, in whom an autoimmune etiology is suspected. We propose a sequential diagnostic strategy, recognizing the importance of the multidisciplinary team and including the autoimmune perspective with emphasis on clinical and serological domains. Other diagnostic tools such as capillaroscopy and minor salivary gland biopsy are also considered. We also take a critical look at the latest guidelines for progressive pulmonary fibrosis, since it is essential that the rheumatologist understands these concepts that are vital in a multidisciplinary team.