Preschooler with cough and fever Pediatric Imaging Chest June 21, 2026March 26, 2026 CXR PA (left) shows a retrocardiac opacity which on the CXR lateral (right) is seen to be located over the lower spine resulting in a spine sign. The diagnosis was bacterial pneumonia in the posterior left lower lobe. Related Published June 21, 2026March 26, 2026