CXR on day 8 of the fever (above left) shows opacities in the left upper lobe and right middle lobe. Axial CT without contrast of the chest on day 13 of the fever (above right) shows parenchymal opacities surrounded by irregular ground glass density (halo sign). CXR on day 20 of the fever (below left) shows interval cavitation of the bilateral lung lesions which on axial CT with contrast of the chest on day 34 of the fever (below right) shows central necrosis in the lesions which is detached from the wall (air crescent sign).
Pediatric Imaging 