Flock Lung Armando E. Fraire Flocking is a widely used industrial process in which short segments of nylon or similar synthetic fibers are applied to backing fabric materials to produce…

Hot-Tub Lung Andras Khoor Hot-tub lung is a diffuse granulomatous interstitial lung disease that develops in immunocompetent individuals caused by inhalation of aerosolized nontuberculous mycobacteria (usually Mycobacterium avium complex), which…

Hypersensitivity Pneumonitis Roberto Barrios Keith M. Kerr Hypersensitivity pneumonitis, also known as hypersensitivity pneumonia and extrinsic allergic alveolitis, is a diffuse interstitial granulomatous pneumonia secondary to inhalation of organic antigens….

Infectious Interstitial Pneumonia Abida K. Haque Infectious interstitial pneumonia is most often the result of viral infection. Several viruses produce this pattern, in addition to causing airway inflammation and necrosis….

Respiratory Bronchiolitis-Associated Interstitial Lung Disease/Desquamative Interstitial Pneumonia Philip T. Cagle Respiratory bronchiolitis may uncommonly be associated with a generally mild and generally nonprogressive interstitial lung disease characterized by dyspnea, cough,…

Respiratory Bronchiolitis Philip T. Cagle Lesions of respiratory bronchiolitis may be observed involving occasional respiratory bronchioles in lung specimens from cigarette smokers unaccompanied by clinically significant findings. Less frequently, respiratory…

Membranous Bronchiolitis Philip T. Cagle Tobacco smoke effects on the small airways can often be measured physiologically as an obstructive change in FEV1, more specifically in FEF25%-75% or FEF75%. When…

Emphysema Timothy C. Allen Philip T. Cagle Emphysema is characterized by destruction of respiratory bronchioles, alveolar ducts, and alveoli leaving enlarged airspaces. There are several types of emphysema, but the…

Pulmonary Alveolar Proteinosis Roberto Barrios Carlos Bedrossian Pulmonary alveolar proteinosis is a rare lesion characterized by accumulation of a granular eosinophilic material in the alveoli. It can be seen as…

Acute Pneumonia Roberto Barrios Acute pneumonia is characterized by acute inflammation of the lung involving distal airspaces. Acute pneumonias can be classified in several different ways: according to epidemiology, pathogenesis,…