Biomarkers on Fibrotic Lung Diseases Associated with Usual Interstitial Pneumonia

Usual interstitial pneumonia (UIP) is a common pattern in fibrotic lung diseases characterized by distinctive radiological and histopathological features.UIP is associated with various underlying causes including idiopathic UIP, i.e. idiopathic pulmonary fibrosis (IPF), and secondary UIP, e.g.connective tissue disease-associated interstitial lung diseases (CTD-ILDs) and fibrotic hypersensitivity pneumonia (fHP).Previous work suggests radiological UIP patterns have strong correlations with overall poor prognosis.This review synthesizes current knowledge on the diverse entities of fibrotic lung diseases presenting with the UIP pattern.This review also highlights previous studies in biomarker searching of IPF and secondary UIP.A number of biomarkers associated with disease diagnosis are summarized, providing new insights for clinicians in disease differentiation.Finally, this review emphasizes the future directions of differential diagnosis through radiology-and blood-biomarkers with the integration of artificial intelligence (AI).