Smoking-related diffuse parenchymal lung disease: HRCT-pathologic correlation

Response by the lung to inhaled cigarette smoke varies widely between individuals and ranges from subclinical respiratory bronchiolitis to end-stage Langerhans' cell histiocytosis. The variety of interstitial lung diseases associated with cigarette smoking is wider than generally appreciated, and these often coexist. An understanding of the pathological basis of smoking-related lung disease helps to explain the sometimes complex patterns encountered on high-resolution computed tomography (HRCT). The recent refinement of the classification of the idiopathic interstitial pneumonias and the longitudinal study of cigarette smokers with HRCT has furthered understanding of what should be regarded as an overlapping group of entities. In this article the individual interstitial diseases ascribable to cigarette smoking are discussed in terms of their pathology and corresponding HRCT signs. Emphasis is placed on the frequent coexistence of various forms of smoking-related interstitial lung disease.