Asthma is an inflammatory disease characterized by increased airway reactivity and by airflow obstruction that is at least partially reversible and results in recurrent episodes of wheezing, breathlessness, and cough….

Pulmonary arterial hypertension (PAH) is defined as a mean pulmonary arterial pressure of greater than 25 mm Hg at rest or 30 mm Hg with exercise, with an elevated pulmonary vascular resistance…

Etiology Silicosis and coal workers’ pneumoconiosis (CWP) are occupational lung diseases; silicosis is caused by continued exposure to excessive amounts of respirable silica, and CWP is caused by exposure to…

Definition and Etiology Emphysema is defined as a “condition of the lung characterized by abnormal, permanent enlargement of the airspaces distal to the terminal bronchiole, accompanied by destruction of their…

Metabolic and storage lung diseases are a broad group of diseases and syndromes characterized by underlying biochemical or metabolic dysfunctions. Accurate diagnosis is difficult because these diseases are often indolent,…

Etiology, Prevalence, and Epidemiology Pulmonary vasculitis is traditionally characterized by size of vessel involvement as defined by the Chapel Hill nomenclature. Within the small-vessel vasculitides, antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis…

Etiology Chronic pulmonary thromboembolism is an uncommon entity resulting from an incomplete resolution of thrombi, leading to complex restructuring processes within pulmonary arteries. Extensive clinical experience from the literature suggests…

Etiology Pulmonary embolism (PE) refers to blood clot(s) within the pulmonary arterial system, usually caused by migration of deep vein thrombosis (DVT) from the lower extremities. Rarely, emboli are from…

Etiology Hypersensitivity pneumonitis (HP), also known as extrinsic allergic alveolitis, is an immune-mediated inflammatory form of diffuse interstitial pulmonary disease caused by inhalation of various antigens that affect susceptible patients….

Sarcoidosis is a systemic inflammatory disorder of unknown etiology that affects multiple organs and is characterized by the formation of noncaseating granulomas. Intrathoracic lymph node and pulmonary parenchymal involvement occurs…