Facts and promises on lung biomarkers in interstitial lung diseases.

Interstitial lung diseases (ILDs) are a heterogeneous group of >100 pulmonary disorders. ILDs are characterized by an irreversible architectural distortion and impaired gas exchange; however, there is great variability in the clinical course. ILD diagnosis requires a combination of clinical data, radiological imaging and histological findings (when a lung biopsy is required). At the same time, successful management of ILD patients strictly depends on an accurate and confident diagnosis. In this context, the detection of reliable biomarkers able to identify ILD subtypes, avoiding lung biopsy, as well as the capacity to stratify patients and predict over time the disease course, has become a primary aim for all research studies in this field.