Humans ; Diagnosis, Differential ; Idiopathic Pulmonary Fibrosis/pathology* ; Lung/pathology*

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease characterized by progressive lung fibrogenesis and histological features of usual interstitial pneumonia. IPF has a poor prognosis and presents a spectrum of disease courses ranging from slow evolving disease to rapid deterioration; thus, a differential diagnosis remains challenging. Several biomarkers have been identified to achieve a differential diagnosis; however, comprehensive reviews are lacking. This review summarizes over 100 biomarkers which can be divided into six categories according to their functions: differentially expressed biomarkers in the IPF compared to healthy controls; biomarkers distinguishing IPF from other types of interstitial lung disease; biomarkers differentiating acute exacerbation of IPF from stable disease; biomarkers predicting disease progression; biomarkers related to disease severity; and biomarkers related to treatment. Specimen used for the diagnosis of IPF included serum, bronchoalveolar lavage fluid, lung tissue, and sputum. IPF-specific biomarkers are of great clinical value for the differential diagnosis of IPF. Currently, the physiological measurements used to evaluate the occurrence of acute exacerbation, disease progression, and disease severity have limitations. Combining physiological measurements with biomarkers may increase the accuracy and sensitivity of diagnosis and disease evaluation of IPF. Most biomarkers described in this review are not routinely used in clinical practice. Future large-scale multicenter studies are required to design and validate suitable biomarker panels that have diagnostic utility for IPF.
Humans ; Idiopathic Pulmonary Fibrosis/diagnosis* ; Biomarkers ; Lung Diseases, Interstitial ; Lung ; Bronchoalveolar Lavage Fluid ; Disease Progression ; Prognosis

Idiopathic pulmonary fibrosis (IPF) is a chronic fatal pulmonary disease characterized by complex illness condition. There is no effective treatment at present except lung transplantation. The comprehensive evaluation is helpful for the management of patients with IPF in hierarchical stages. Therefore, it is very important to evaluate IPF by various independent factors. At present, the commonly used methods for clinical evaluation on IPF include assessment of health-related quality of life, assessment of physiological function, assessment of imaging, assessment of laboratory examination, and multi-dimensional assessment system. However, there are different advantages and disadvantages on diverse evaluation methods for the evaluation of IPF.
Humans ; Idiopathic Pulmonary Fibrosis/diagnosis* ; Quality of Life

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia characterized by progressive accumulation of fibroblastic foci and destruction of the alveolar structure. Due to an incomplete understanding of the mechanism of the occurrence and progression of IPF, currently no effective means have been available for its early screening or treatment. With a poor overall prognosis, the patients with IPF have a median survival of only 2-4 years. In recent years, several studies have confirmed that dozens of molecules are involved in the development of IPF and can be used as potential biomarkers. These biomarkers play important roles in early diagnosis (such as SP-D, MMP-7, and osteopontin), prognostic evaluation (such as telomerase length, KL-6, mtDNA, HSP-70, LOXL2, CXCL13, miRNA, ICAM-1, and CCL18), and guiding treatment of IPF (such as TOLLIP rs3750920 genotype, SAMS score, and SP-D), and also provide potential therapeutic targets (such as TERT, TERR, RTEC, and PARN).
Amino Acid Oxidoreductases ; metabolism ; Biomarkers ; analysis ; Disease Progression ; Humans ; Idiopathic Pulmonary Fibrosis ; diagnosis ; therapy ; Intracellular Signaling Peptides and Proteins ; metabolism ; Prognosis

Interstitial lung disease (ILD) is a rare condition characterized by extensive inflammation and fibrosis mainly involving the pulmonary interstitium or alveoli. Usually, patients with ILD clinically present with chronic cough and exertional dyspnea. ILD is classified into subtypes based on clinical characteristics, detailed history obtained from patients, and radiological, and/or histopathological features. The most common type of idiopathic interstitial pneumonia is idiopathic pulmonary fibrosis (IPF). IPF is a chronic progressive fibrosing ILD and is associated with poor prognosis. An exclusive diagnosis of IPF requires no known condition causing ILD and typical radiological and/or histopathological features of lung fibrosis. Fibrosis observed in this condition is attributable to repetitive epithelial injury with consequent abnormal wound healing in genetically susceptible and elderly individuals. Currently, pirfenidone and nintedanib are useful disease-modifying agents available to treat IPF. In this article, we review the concept, diagnosis, clinical course, and treatment of ILD.
Aged ; Cough ; Diagnosis ; Dyspnea ; Fibrosis ; Humans ; Idiopathic Interstitial Pneumonias ; Idiopathic Pulmonary Fibrosis ; Inflammation ; Lung ; Lung Diseases, Interstitial ; Prognosis ; Wound Healing

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrosing interstitial lung disease characterized by worsening lung function and dyspnea. The prognosis of IPF patients is poor, as median survival is approximately 3 years. However, recently developed IPF-specific therapies have shown improved efficacies in terms of reducing lung function decline and mortality. Therefore, the early recognition and accurate diagnosis of IPF are crucial. In 2018, new guidelines for the diagnosis of IPF were published by the Fleischner Society and by the American Thoracic Society/European Respiratory Society/Japanese Respiratory Society/Latin American Thoracic Society (ATS/ERS/JRS/ALAT). Both guidelines emphasize the need for a thorough history taking and physical examination to exclude an alternative diagnosis, such as exposure-related or connective tissue disease. The most informative initial examination is high-resolution computed tomography, the results of which can indicate the need for bronchoalveolar lavage or surgical lung biopsy, based on a multidisciplinary discussion of the findings and the patient's clinical condition. A multidisciplinary discussion of the clinico-radiologic-pathologic findings is currently the gold standard in the diagnoisis of IPF and will allow the more effective and timely treatment of these patients.
Biopsy ; Bronchoalveolar Lavage ; Connective Tissue Diseases ; Diagnosis ; Dyspnea ; Humans ; Idiopathic Pulmonary Fibrosis ; Lung ; Lung Diseases, Interstitial ; Mortality ; Physical Examination ; Prognosis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrosing interstitial pneumonia, which presents with a progressive worsening dyspnea, and thus a poor outcome. The members of the Korean Academy of Tuberculosis and Respiratory Diseases as well as the participating members of the Korea Interstitial Lung Disease Study Group drafted this clinical practice guideline for IPF management. This guideline includes a wide range of topics, including the epidemiology, pathogenesis, risk factors, clinical features, diagnosis, treatment, prognosis, and acute exacerbation of IPF in Korea. Additionally, we suggested the PICO for the use of pirfenidone and nintendanib and for lung transplantation for the treatment of patients with IPF through a systemic literature review using experts' help in conducting a meta-analysis. We recommend this guideline to physicians, other health care professionals, and government personnel in Korea, to facilitate the treatment of patients with IPF.
Delivery of Health Care ; Diagnosis ; Disease Management ; Dyspnea ; Epidemiology ; Humans ; Idiopathic Pulmonary Fibrosis ; Korea ; Lung Diseases, Interstitial ; Lung Transplantation ; Prognosis ; Risk Factors ; Tuberculosis

Idiopathic nonspecific interstitial pneumonia (NSIP) is one of the varieties of idiopathic interstitial pneumonias. Diagnosis of idiopathic NSIP can be done via multidisciplinary approach in which the clinical, radiologic, and pathologic findings were discussed together and exclude other causes. Clinical manifestations include subacute or chronic dyspnea and cough that last an average of 6 months, most of which occur in non-smoking, middle-aged women. The common findings in thoracic high-resolution computed tomography in NSIP are bilateral reticular opacities, traction bronchiectasis, reduced volume of the lobes, and ground-glass opacity in the lower lungs. These lesions can involve diffuse bilateral lungs or subpleural area. Unlike usual interstitial pneumonia, honeycombing is sparse or absent. Pathology shows diffuse interstitial inflammation and fibrosis which are temporally homogeneous, namely NSIP pattern. Idiopathic NSIP is usually treated with steroid only or combination with immunosuppressive agents such as azathioprine, cyclophosphamide, cyclosporine, and mycophenolate mofetil. Prognosis of idiopathic NSIP is better than idiopathic pulmonary fibrosis. Many studies have reported a 5-year survival rate of more than 70%.
Azathioprine ; Bronchiectasis ; Cough ; Cyclophosphamide ; Cyclosporine ; Diagnosis ; Dyspnea ; Female ; Fibrosis ; Humans ; Idiopathic Interstitial Pneumonias ; Idiopathic Pulmonary Fibrosis ; Immunosuppressive Agents ; Inflammation ; Lung ; Lung Diseases, Interstitial ; Pathology ; Prognosis ; Survival Rate ; Traction

Idiopathic interstitial pneumonia (IIP) is a histologically identifiable pulmonary disease without a known cause that usually infiltrates the lung interstitium. IIP is largely classified into idiopathic pulmonary fibrosis, idiopathic non-specific interstitial pneumonia, respiratory bronchiolitis-interstitial lung disease (ILD), cryptogenic organizing pneumonia, desquamative interstitial pneumonia, and acute interstitial pneumonia. Each of these diseases has a different prognosis and requires specific treatment, and a multidisciplinary approach that combines chest high-resolution computed tomography (HRCT), histological findings, and clinical findings is necessary for their diagnosis. Diagnosis of IIP is made based on clinical presentation, chest HRCT findings, results of pulmonary function tests, and histological findings. For histological diagnosis, video-assisted thoracoscopic biopsy and transbronchial lung biopsy are used. In order to identify ILD associated with connective tissue disease, autoimmune antibody tests may also be necessary. Many biomarkers associated with disease prognosis have been recently discovered, and future research on their clinical significance is necessary. The diagnosis of ILD is difficult because patterns of ILD are both complicated and variable. Therefore, as with other diseases, accurate history taking and meticulous physical examination are crucial.
Biomarkers ; Biopsy ; Classification ; Connective Tissue Diseases ; Cryptogenic Organizing Pneumonia ; Diagnosis ; Idiopathic Interstitial Pneumonias ; Idiopathic Pulmonary Fibrosis ; Lung ; Lung Diseases ; Lung Diseases, Interstitial ; Physical Examination ; Prognosis ; Respiratory Function Tests ; Thorax

Connective tissue diseases (CTDs) can affect all compartments of the lungs, including airways, alveoli, interstitium, vessels, and pleura. CTD-associated lung diseases (CTD-LDs) may present as diffuse lung disease or as focal lesions, and there is significant heterogeneity between the individual CTDs in their clinical and pathological manifestations. CTD-LDs may presage the clinical diagnosis a primary CTD, or it may develop in the context of an established CTD diagnosis. CTD-LDs reveal acute, chronic or mixed pattern of lung and pleural manifestations. Histopathological findings of diverse morphological changes can be present in CTD-LDs airway lesions (chronic bronchitis/bronchiolitis, follicular bronchiolitis, etc.), interstitial lung diseases (nonspecific interstitial pneumonia/fibrosis, usual interstitial pneumonia, lymphocytic interstitial pneumonia, diffuse alveolar damage, and organizing pneumonia), pleural changes (acute fibrinous or chronic fibrous pleuritis), and vascular changes (vasculitis, capillaritis, pulmonary hemorrhage, etc.). CTD patients can be exposed to various infectious diseases when taking immunosuppressive drugs. Histopathological patterns of CTD-LDs are generally nonspecific, and other diseases that can cause similar lesions in the lungs must be considered before the diagnosis of CTD-LDs. A multidisciplinary team involving pathologists, clinicians, and radiologists can adequately make a proper diagnosis of CTD-LDs.
Bronchiolitis ; Communicable Diseases ; Connective Tissue Diseases ; Connective Tissue ; Diagnosis ; Fibrin ; Hemorrhage ; Humans ; Idiopathic Pulmonary Fibrosis ; Lung Diseases ; Lung Diseases, Interstitial ; Lung ; Pleura ; Pleural Diseases ; Population Characteristics