Surfactant Dysfunction

Genetic surfactant dysfunction disorders are caused by mutations in genes encoding proteins critical for the production and function of pulmonary surfactant. These rare disorders may produce familial or sporadic lung disease, with clinical presentations ranging from neonatal respiratory failure to childhood- or adult-onset interstitial lung disease. An overview of these disorders is presented in the table.. Interstitial lung diseases in children until recently were categorized by their histologic appearance in a manner similar to that used for adult forms of interstitial lung disease (ILD). In children, the lung histopathology findings associated with desquamative interstitial pneumonitis (DIP) are now known to often result from genetic mechanisms that disrupt normal surfactant production and metabolism. By contrast, DIP in adults is considered to represent a distinct type of ILD, which is strongly associated with cigarette smoking and carries a relatively favorable prognosis [1]. These genetic disorders also result in histopathologic patterns other than DIP, including findings of pulmonary alveolar proteinosis and chronic pneumonitis of infancy. An understanding of the pathogenesis of these disorders permits a mechanistic classification as genetic surfactant dysfunction disorders instead of their previous classification based upon histologic appearance.