Mac-Leod-Swyer-James-Syndrome

A rare lung condition characterized by often predominantly unilateral lung hyperlucency and air trapping. The condition is a post-infectious form of bronchiolitis obliterans and typically follows a viral respiratory infection in infancy and childhood. Adenovirus infection is considered the most usual epidemiology. In SJS, the involved lung or portion of the lung does not grow normally and is slightly smaller than the opposite lung: in particular, peripheral branches of the pulmonary vessels do not develop, and vasculature is arreseted at the stage at which the infection occurred. Patients respond well to management with bronchodilators, even though this is not primarily a bronchial abnormality.

Definition from the Mondo Disease Ontology (MONDO:0800120), read 2026-09-29. CC BY 4.0.