Evaluation and management of Idiopathic Pulmonary Fibrosis

Abstract

Idiopathic Pulmonary Fibrosis (IPF) is a most common progressive interstitial lung disease (ILD) of unknown etiology, although majority of patients are elderly male smokers. The main pathogenesis is aberrant recovery of epithelial injury and collagen deposition. Fibrotic nonspecific interstitial pneumonia, connective tissue disease (CTD) especially rheumatoid arthritis (RA) associated ILD, and chronic hypersensitivity pneumonia(CHP) are important differential diagnosis. Main symptoms are non-productive cough and progressive exertional dyspnea. Crucial physical findings are scalene muscle hypertrophy, bibasilar fine crackles, and finger clubbing. The serum markers such as lactate dehydrogenase (LDH) and Krebs von den Lungen-6 (KL-6) are sensitive for ILD detection and activity. Both pulmonary function test (PFT) and the 6-minute walk test (6MWT) are useful tool for evaluation of disease progression of IPF. Serial changes of forced vital capacity (FVC) and 6MWT distance predict mortality in IPF effectively. Recently published international IPF guidelines highlight the importance of chest high resolution computed tomography (HRCT) findings such as honeycombing, traction bronchiectasis (TBE), and sub-pleural reticular opacity. IPF is chronic and progressive; therefore, tracking disease behavior is crucial. Unifying clinical, physiological, and imaging information over time is useful. With regard to its management, two anti-fibrotic drugs such as pirfenidone and nintedanib have been available. These drugs can slow the decline of FVC and prevent acute exacerbation (AE). In this review, I outline the clinical characteristics of IPF, physiological, imaging, pathological findings and review diagnosis process and management.

Keywords: Anti-fibrotic drug; Clinical disease behavior; Dyspnea; Forced vital capacity; High resolution computed tomography.