[Swyer-James or Macleod syndrome or unilateral translucent lung].

The syndrome, described by Swyer and James in 1953 and by Macleod in 1954 is a specific entity within a much larger group of radiological conditions brought together under the term of unilateral translucent lung. Generally acquired in childhood subsequent to viral bronchopulmonary infections, the syndrome is caused by predominantly unilateral obliteration of the distal bronchi. The lung is usually small as the infection during childhood inhibited the normal growth pattern. Two elements found in all patients are trapped air and distal bronchiol obstruction. Pulmonary vascularization is greatly reduced leading to radiological translucency. Clinical signs are usually absent. We report two cases illustrating late diagnosis in adults and focus on the novel aspects of this syndrome as well as recent pathogenic hypotheses and diagnostic approach.