Patterns of lung fibrosis in patients with interstitial pneumonia with autoimmune features and connective tissue diseases-associated interstitial lung disease—a narrative review

Interstitial pneumonia with autoimmune features (IPAF) was defined in 2015 as a research statement of European Respiratory Society and American Thoracic Society. Connective tissue diseases (CTDs) manifest in the respiratory tract, the main manifestation being interstitial lung disease, which contributes to morbidity and mortality. This poses numerous clinical challenges and is a substantial burden on healthcare systems around the world. The objective of this narrative review was to provide readers with a comprehensive and extensive overview of such manifestations in the respiratory system, analysis of prevalence of specific manifestations in the lung and to characterize population of patients with IPAF.