Pneumonia complications: Macleod's syndrome (Swyer-James syndrome)

This picture shows a chest x-ray of a child with Macleod's syndrome (Swyer-James syndrome) which developed post-pneumonia. The left lung is smaller than the right and is hyperlucent due to reduced lung blood flow on that side. Macleod's syndrome is a chronic condition that is relatively uncommon. The cause is thought to be a viral pneumonia early in life which causes developmental arrest in the affected lung. There are reduced alveolar numbers, and reduced blood flow to that side, giving the appearance of a small, hyperlucent lung. A CT scan may show areas of abnormality on the opposite side. Bronchiectasis may be found in the more damaged lung, though it is not apparent in this x-ray. Management is symptomatic, with antibiotics and physiotherapy if there is an acute respiratory exacerbation.